Predictive Modeling of Drug-Related Adverse Events with Real-World Data: A Case Study of Linezolid Hematologic Outcomes

Electronic health records (EHRs) provide meaningful knowledge of drug-related adverse events (AEs) that are not captured in standard drug development and postmarketing surveillance. Using variables obtained from EHR data in the University of California San Francisco de-identified Clinical Data Warehouse, we aimed to evaluate the potential of machine learning to predict two hematological AEs, thrombocytopenia and anemia, in a cohort of patients treated with linezolid for 3 or more days. Features for model input were extracted at linezolid initiation (index), and outcomes were characterized from index to 14 days post-treatment. Random forest classification (RFC) was used for AE prediction, and reduced feature models were evaluated using cumulative importance (cImp) for feature selection. Grade 3+ thrombocytopenia and anemia occurred in 31% of 2,171 and 56% of 2,170 evaluable patients, respectively. Of the total 53 features, as few as 7 contributed at least 50% cImp, resulting in prediction accuracies of 70% or higher and area under the receiver operating characteristic curves of 0.886 for grade 3+ thrombocytopenia and 0.759 for grade 3+ anemia. Sensitivity analyses in strictly defined patient subgroups revealed similarly high predictive performance in full and reduced feature models. A logistic regression model with the same 50% cImp features showed similar predictive performance as RFC and good concordance with RFC probability predictions after isotonic calibration, adding interpretability. Collectively, this work demonstrates potential for machine learning prediction of AE risk in real-world patients using few variables regularly available in EHRs, which may aid in clinical decision making and/or monitoring.

Pediatric Sepsis Phenotypes and Outcome: 5-Year Retrospective Cohort Study in a Single Center in India (2017-2022)

OBJECTIVES

To describe mortality associated with different clinical phenotypes of sepsis in children.

DESIGN

Retrospective study.

SETTING

PICU of a tertiary care center in India from 2017 to 2022.

PATIENTS

Six hundred twelve children (from 2 mo to 17 yr old) with a retrospectively applied diagnosis of sepsis using 2020 guidance.

METHODS

The main outcome was mortality associated with sepsis subtypes. Other analyses included assessment of risk factors, requirement for organ support, and PICU resources used by sepsis phenotype. Clinical data were recorded on a predesigned proforma.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Of the 612 children identified, there were 382 (62%) with sepsis but no multiple organ failure (NoMOF), 48 (8%) with thrombocytopenia-associated MOF (TAMOF), 140 (23%) with MOF without thrombocytopenia, and 40 (6.5%) with sequential MOF (SMOF). Mortality was higher in the SMOF (20/40 [50%]), MOF (62/140 [44%]) and TAMOF (20/48 [42%]) groups, compared with NoMOF group (82/382 [21%] [ p < 0.001]). The requirement for organ support and PICU resources was higher in all phenotypes with MOF as compared with those without MOF. On multivariable analysis elevated lactate and having MOF were associated with greater odds of mortality.

CONCLUSIONS

In this single-center experience of sepsis in India, we found that sepsis phenotypes having MOF were associated with mortality and the requirement of PICU resources. Prospective studies in different regions of the world will help identify a classification of pediatric sepsis that is more widely applicable.

Risk factors of rituximab-induced thrombocytopenia in patients with autoimmune bullous diseases

Rituximab has been the mainstay treatment for autoimmune bullous diseases (AIBDs). Among the side effects of rituximab, rituximab-induced thrombocytopenia (RIT) is a rare but critical complication. However, there have been no reports or identification of risk factors for RIT in patients with AIBD. In our retrospective study, we compared rituximab-treated AIBD in patients with and without thrombocytopenia to explore the risk factors. In addition, we compared two different rituximab protocols (rheumatoid arthritis [RA] and lymphoma) in terms of the incidence and severity of thrombocytopenia. A total of 222 patients were enrolled, and 46 patients (20.7%) developed RIT. Multivariate logistic regression analysis identified age and chronic kidney disease (CKD) as significant factors for RIT. We also found that patients treated with the lymphoma protocol demonstrated a significantly higher mean post-rituximab platelet count compared with those on the RA protocol. This was the first analysis, to our knowledge, of risk factors for RIT in patients with AIBD. Individuals aged 70 or older and those with multiple comorbidities, particularly CKD, should be closely monitored for thrombocytopenia. For patients with CKD, it may be safer to use the lymphoma protocol for rituximab administration as it results in a lesser reduction in post-rituximab platelet count.

Characteristics and outcomes of COVID-19 in Chinese immune thrombocytopenia patients: A prospective cohort study

The coronavirus disease 2019 (COVID-19) pandemic has a significant impact on the immune system. This is the first and largest study on pre-existing immune thrombocytopenia (ITP) patients infected with COVID-19 in China. We prospectively collected ITP patients infected with COVID-19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty-eight pre-existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty-seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25-2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO-RAs) (OR, 2.27; 95% CI, 1.60-3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09-3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12-5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63-7.64; p = 0.001), maintenance therapy including TPO-RAs (OR, 2.14; 95% CI, 1.17-3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17-7.91; p = 0.02). In this cohort study, we described the characteristics of pre-existing ITP patients infected with COVID-19 and identified several factors associated with poor outcomes.

Incidence rates of thrombosis with thrombocytopenia syndrome (TTS) among adults in United States commercial and Medicare claims databases, 2017-2020

BACKGROUND

Increased risk of thrombosis with thrombocytopenia syndrome (TTS) following adenovirus vector-based COVID-19 vaccinations has been identified in passive surveillance systems. TTS incidence rates (IRs) in the United States (U.S.) are needed to contextualize reports following COVID-19 vaccination.

METHODS

We estimated annual and monthly IRs of overall TTS, common site TTS, and unusual site TTS for adults aged 18-64 years in Carelon Research and MarketScan commercial claims (2017-Oct 2020), CVS Health and Optum commercial claims (2019-Oct 2020), and adults aged ≥ 65 years using CMS Medicare claims (2019-Oct 2020); IRs were stratified by age, sex, and race/ethnicity (CMS Medicare).

RESULTS

Across data sources, annual IRs for overall TTS were similar between Jan-Dec 2019 and Jan-Oct 2020. Rates were higher in Medicare (IRs: 370.72 and 365.63 per 100,000 person-years for 2019 and 2020, respectively) than commercial data sources (MarketScan IRs: 24.21 and 24.06 per 100,000 person-years; Optum IRs: 32.60 and 31.29 per 100,000 person-years; Carelon Research IRs: 24.46 and 26.16 per 100,000 person-years; CVS Health IRs: 30.31 and 30.25 per 100,000 person-years). Across years and databases, common site TTS IRs increased with age and were higher among males. Among adults aged ≥ 65 years, the common site TTS IR was highest among non-Hispanic black adults. Annual unusual site TTS IRs ranged between 2.02 and 3.04 (commercial) and 12.49 (Medicare) per 100,000 person-years for Jan-Dec 2019; IRs ranged between 1.53 and 2.67 (commercial) and 11.57 (Medicare) per 100,000 person-years for Jan-Oct 2020. Unusual site TTS IRs were higher in males and increased with age in commercial data sources; among adults aged ≥ 65 years, IRs decreased with age and were highest among non-Hispanic American Indian/Alaska native adults.

CONCLUSION

TTS IRs were generally similar across years, higher for males, and increased with age. These rates may contribute to surveillance of post-vaccination TTS.

Association of clinical factors with thrombocytopenia in patients receiving linezolid treatment: a retrospective study

INTRODUCTION

Linezolid (LZD) plays an important role in the treatment of severe infections caused by Gram-positive bacteria. Thrombocytopenia is regarded as one of the most common side effects of linezolid, which results from the destruction of platelets or myelosuppression. The study aimed to identify the risk factors associated with the development of thrombocytopenia in Vietnamese patients.

METHODOLOGY

This retrospective, descriptive cross-sectional study was performed on adult patients who received parenteral LZD therapy (1,200 mg/day) in at least 3 days between January 2020 and June 2021 at a tertiary referral hospital in Vietnam. Thrombocytopenia was defined as either a final platelet count of less than 100 G/L or a 25% decrease in platelet count from baseline. Multivariate logistic regression analysis was applied to predict risk factors associated with LZD-induced thrombocytopenia.

RESULTS

In the 208 patients included in the study, the average age was 69 and males accounted for 73.1%. LZD-induced thrombocytopenia occurred in 37% of patients. LZD-induced thrombocytopenia was significantly associated with shock (HR = 8.26, 95% CI 3.82 - 17.84, p < 0.001), baseline creatinine clearance (HR = 1.02, 95% CI [1.01 - 1.03], p = 0.002), and duration of LZD treatment of at least 14 days (HR = 4.45, 95% CI [1.83 - 11.05], p = 0.001).

CONCLUSIONS

The results showed that thrombocytopenia was fairly common in patients using linezolid. Shock, renal failure, and duration of linezolid therapy of at least 14 days were significant risk factors for the incidence of linezolid-induced thrombocytopenia.

Development and validation of a risk prediction model for linezolid-induced thrombocytopenia in elderly patients

OBJECTIVES

Linezolid is the first oxazolidinone antimicrobial agent developed for treating multi-drug-resistant gram-positive bacterial infections. The study aimed to investigate the risk factors of linezolid (LI)-induced thrombocytopenia (LI-TP) and to develop and validate a risk prediction model to identify elderly patients at high risk of developing LI-TP during linezolid therapy.

METHODS

A retrospective cohort study was performed at Zhongshan Hospital, FuDan University, China. The study involved elderly Chinese patients aged ≥65 years administered with linezolid (600 mg) twice a day between January 2015 and April 2021. We collected the patients' clinical characteristics and demographic data from electronic medical records, and compared the differences between LI-TP patients and those who had not developed thrombocytopenia (NO-TP) after linezolid treatment. The risk prediction model was developed based on the regression coefficient generated from logistic regression model.

RESULTS

A total of 343 inpatients were enrolled from January 2015 to August 2020 and were used as the training set. Among them, 67 (19.5%) developed LI-TP. Multivariate logistic regression analysis revealed that baseline platelet counts <150×109·L-1 (odds ratio (OR)=3.576; p<0.001), age ≥75 years (OR=2.258; p=0.009), estimated glomerular filtration rate (eGFR <60 mL·(min·1.73 m2)-1 (OR=2.553; p=0.002), duration of linezolid therapy ≥10 d (OR=3.218; p<0.001), intensive care unit (ICU) admittance (OR=2.682; p=0.004), concomitant piperacillin-tazobactam (OR=3.863; p=0.006) were independent risk factors for LI-TP in elderly patients. The LI-TP risk prediction model was established using a scoring method based on the regression coefficient and exhibited a good discriminative power, with an area under the curve (AUC) of 0.795 (95% confidence interval (CI) 0.740 to 0.851) and 0.849 (95% CI 0.760 to 0.939) in the training set (n=343) and validation set (n=90) respectively.

CONCLUSIONS

These findings indicate that duration of linezolid therapy, age, eGFR, ICU admittance, baseline platelet counts, concomitant piperacillin-tazobactam were significantly associated with LI-TP in elderly patients. A risk prediction model based on these risk factors showed a good discriminative performance and may be useful for clinicians to identify patients at high risk of developing LI-TP.

Prospective evaluation of bleeding risk among thrombocytopenic patients admitted in intensive care unit

PURPOSE

Bleeding risk evaluation of thrombocytopenic patients admitted in ICU has been poorly investigated.

METHODS

A prospective observational study conducted in an 18-bed medical ICU. Consecutive patients with thrombocytopenia (<150 Giga/L) and no bleeding at admission were included.

RESULTS

Over one year, 91 patients were included, mainly men (63%), with an age of 61 [46-68] years and a SOFA score of 6 [3-8]. Twenty-three patients (25%) had an hemorrhagic event during ICU stay, mainly digestive (n = 9; 39%) and urological (n = 6; 26%). The time between ICU admission and bleeding was 8 [2-19] days. Almost half of bleeding events required vasopressor infusion and a hemostatic procedure. At admission, two variables were significantly different between the Bleeding and No-Bleeding groups: plasma urea level was significantly higher in the Bleeding group (9 [5.1; 13] vs. 13 [8.9; 31] mmol/L; p < 0.001) and the presence of skin purpura was associated with a 3-fold higher risk for bleeding during ICU stay (HR: 3.4 [1.3-8.3]; p < 0.05). In contrast, admission platelet count was not significantly different between the 2 groups (90 [32; 128] vs 62 [36; 103] G/L; p = 0.26).

CONCLUSION

Plasma urea levels and the presence of skin purpura are helpful in identifying thrombocytopenic patients at high-risk of bleeding during ICU stay.

The investigation of thrombocytopenia after transcatheter occlusion of patent ductus arteriosus

OBJECTIVE

To investigate the risk factors for thrombocytopenia after transcatheter occlusion operation of patent ductus arteriosus (PDA).

METHOD

Retrospective analyses were conducted using clinical data from 106 patients with PDA who underwent transcatheter closure operations at Henan Provincial Chest Hospital, Zhengzhou University, from January 2018 to June 2022. The study compared the changes in platelet counts before and after the operation, and investigated the risk factors for thrombocytopenia following PDA closure in different groups and layers.

RESULTS

The platelet count of patients with PDA significantly decreased after undergoing transcatheter PDA occlusion. Logistic regression analysis revealed that factors such as PDA diameter, occluder diameter, pressure difference on the two sides of the occluder, and residual shunt were associated with an increased risk of thrombocytopenia following PDA occlusion. Specifically, the size of the occluder and the pressure difference between the two sides of the occluder were found to have a negative correlation with the postoperative platelet count. Further subgroup analysis demonstrated that the incidence of total thrombocytopenia was significantly higher in the large PDA group compared to the small-medium PDA groups.

CONCLUSION

Our findings suggest that occluder diameter, the pressure difference between the two sides of the occluder, and the residual shunt are major risk factors correlated with the incidence of postoperative thrombocytopenia. However, a multicenter and long-term prospective study is required to further evaluate the prognosis of PDA patients with thrombocytopenia after transcatheter occlusion.

Thrombocytopenia and associated factors among pregnant women attending antenatal care at Hiwot Fana Comprehensive Specialized Hospital, Eastern Ethiopia: A cross-sectional study

Thrombocytopenia (TCP) is the second most common hematological change during pregnancy and is considered as a major source of maternal and neonatal morbidity and mortality. Despite its effects to morbidity and mortality, it is frequently ignored or disregarded, particularly in resource-limited nations. Thus, the purpose of this study was to determine the prevalence of thrombocytopenia and associated factors among pregnant women attending antenatal care at Hiwot Fana Comprehensive Specialized University Hospital, Eastern Ethiopia from June 20 to August 30, 2022. A hospital-based cross-sectional study was conducted among 199 pregnant women selected through a systematic sampling technique. Ethical approval was obtained from the Ethics Review Committee of Haramaya University. Data related to sociodemographic and reproductive variables were collected using structured questionnaires. Four milliliters of venous blood were collected from each study participant and a complete blood cell count was determined using UniCel DxH 800 hematology analyzer. Logistic regression analysis was done to assess the association between TCP and independent variables and P < .05 was considered statistically significant. In this study, the prevalence of TCP was 14.1% (95% CI: 9.6-19.7). Of them, 10 (35.7%), 12 (42.9%), and 4 (21.4%) had mild, moderate, and severe TCP, respectively. Having more than 3 children (adjusted odds ratio, AOR = 7.90, 95% CI: 2.60, 24.3), no antenatal care follow-up (AOR = 7.90, 95% CI: 2.40-26.2), being in the second and third trimester (AOR = 6.90, 95% CI: 1.70, 28.9 and AOR = 5.04, 95% CI: 1.12, 22.7, respectively), and history of heavy menstrual bleeding (AOR = 4.03, 95% CI: 1.25, 13.1) were significantly associated with TCP. TCP is a public health problem among pregnant women in the study area. Having more than 3 children, lack of antenatal care follow-up, being in the second and third trimesters, and having history of heavy menstrual bleeding was significantly associated with TCP. As a result, regular platelet count monitoring and appropriate intervention approaches based on identified predictors should be explored to mitigate adverse outcomes in pregnant women.

[Epidemiological characteristics of severe fever with thrombocytopenia syndrome in China, 2018-2021]

Objective: To understand the epidemiological characteristics and incidence trend of severe fever with thrombocytopenia syndrome (SFTS) in China. Methods: The incidence data of SFTS in China from 2018 to 2021 were collected from Chinese Disease Prevention and Control Information System for a statistical and descriptive epidemiological analysis by using software such as Excel 2016, Joinpoint 5.0.2, SPSS 26.0, and GraphPad Prism 8.0, especially, the SFTS cases reported monthly by key provinces were analyzed. Results: From 2018 to 2021, a total of 8 835 SFTS cases were reported in 25 provinces and the annual incidence showed an upward trend. The distribution of SFTS cases showed clustering, but the cases were mainly sporadic ones. The cases began to increase in March, mainly occurred during April to October (96.79%,8 551/8 835), and peaked during May to July. The cases were mainly distributed in middle-aged and old farmers, and slight more cases were women. The average case fatality rate was 5.38%, which varied greatly with areas. The case fatality rate tended to increase with age. Conclusion: From 2018 to 2021, the epidemiological characteristics of SFTS in China remained stable, but the number of reported cases gradually increased and the distribution showed an expanding trend, to which close attention should be paid.

Thrombocytopenia and disease outcomes in a cohort of patients with systemic lupus erythematosus. A post hoc analysis of the COMOSLE-EGYPT study

BACKGROUND

Thrombocytopenia ranges from 20% to 40% in patients with systemic lupus erythematosus (SLE). It is usually associated with severe disease manifestations and worse disease outcomes.

AIM OF THE STUDY

To identify the frequency of thrombocytopenia in a cohort of Egyptian patients with SLE and to examine the relationship of thrombocytopenia with various disease manifestations and disease outcomes.

METHODS

Data on 902 SLE patients were collected, including demographics, clinical, laboratory, immunological findings, and medications. SLE Disease Activity Index (SLEDAI) at baseline, last visit, and Systemic Lupus International Collaborating Clinics/ACR Damage Index (SLICC) were calculated. A comparison was done between patients with thrombocytopenia (group I) and patients without (group II) regarding different disease parameters. Regression analysis was done to examine if thrombocytopenia is a predictor of worse disease outcomes.

RESULTS

Thrombocytopenia was found in 33% of our cohort. Longer disease duration was observed in group I compared to group II (p value = .01). As regards clinical manifestations, significantly higher frequencies of constitutional manifestations, anemia, arterial thrombosis, pulmonary hypertension, cardiac manifestations, neurological manifestations, gastrointestinal tract (GIT), and hepatic manifestations were detected in group I compared to group II. The disease damage index was detected to be significantly higher in group I as compared to group II (p value < .001). Mortality was higher in group I (p value < .001). Although it was found that antiphospholipid antibodies (APL) were associated with thrombocytopenia and their presence resulted in higher damage (p value: .001), the presence of thrombocytopenia even in patients with negative APL antibodies was associated with higher damage and mortality. Apart from thrombocytopenia, the male gender was also found to be an independent risk factor for mortality.

CONCLUSION

Thrombocytopenia was associated with more organ damage and higher mortality in SLE patients with or without APL antibodies. SLE patients with thrombocytopenia have a 3.4 times higher risk of mortality than patients without thrombocytopenia. Apart from thrombocytopenia, the male gender was also found to be an independent risk factor for mortality.

Cardiac injury in hospitalized patients with severe fever and thrombocytopenia syndrome

Severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease with a high fatality rate. Cardiac injury in SFTS patients is a major concern. This study aimed to evaluate the prevalence of cardiac injury and its association with mortality in hospitalized patients infected with novel Bunyavirus. Cardiac injury was defined as the presence of any of the following abnormalities: (1) blood levels of cardiac biomarkers (creatine kinase-MB, troponin-I, B-type natriuretic peptide or N-terminal pro-B-type natriuretic peptide); (2) new abnormalities in electrocardiography. The 203 SFTS patients were included in the final analysis. The proportion of SFTS patients developing cardiac injury during hospitalization was 71.4% (145/203). Compared with the uninjured group, the cardiac injury group had the severity of cardiac injury was underscored by higher median hospital costs (31420 vs. 12911, p < 0.001), higher proportion of intensive care units admissions (13.1% vs. 3.4%, p = 0.041), and higher hospital mortality rate (33.8% vs. 6.9%, p < 0.001). Multivariable-adjusted Cox proportional hazards regression analysis showed that cardiac injury was associated with higher mortality during hospitalization (hazards ratio, 7.349; 95% CI: 2.352-22.960). Cardiac injury is common among hospitalized SFTS patients, and it is associated with higher risk of mortality.

Heparin-Induced Thrombocytopenia After Cardiac Surgery-A Statewide Review of Health Care Utilization

BACKGROUND

Despite its severe consequences, clinical and economic impacts of heparin-induced thrombocytopenia (HIT) after cardiac operations have not been well characterized. This study assessed statewide incidence, outcomes, and resource consumption associated with HIT after cardiac operations.

METHODS

This was a retrospective investigation of cardiac surgery patients using the Maryland Health Services Cost Review Commission's database from 2012 to 2020. Health care costs, utilization, and outcomes for those who experienced postoperative HIT were compared with propensity score-matched controls.

RESULTS

Of 33 583 cardiac surgery patients, 184 (0.55%) were diagnosed with postoperative HIT. Compared with non-HIT patients, HIT patients were significantly more likely to be in the oldest age group (>80 years; P < .001) and to have greater severity of illness at admission (P < .001). HIT was associated with a longer hospitalization (21 vs 7 days; P < .001), greater mortality (13.6% vs 2.3%; P < .001), and greater hospital charges ($123 160 vs $45 303; P < .001), even after propensity score matching. Readmission rates were not significantly different, however, and readmission hospital charges did not significantly differ between HIT and non-HIT patients.

CONCLUSIONS

In addition to worse outcomes, HIT was associated with higher costs during index admissions but not during readmissions of cardiac surgery patients. Strategies to minimize HIT could yield better outcomes and reduced costs, particularly relevant for health care systems seeking improved value-based care while reducing unnecessary hospitalizations.

Impact of heart failure and preoperative platelet count on the postoperative short-term outcome in infective endocarditis patients

BACKGROUND

Heart failure (HF) and platelet count are often considered risk factors for mortality in patients with infective endocarditis (IE); however, their effects on various complications have not been elucidated.

HYPOTHESIS

We speculated that HF and platelet count have significant impact on the short-term outcomes of IE.

METHODS

This single-center retrospective study analyzed data from 320 IE patients who underwent surgery. A multivariate Cox proportional hazards model was used to identify the risk factors for adverse outcomes. The effect of the platelet count on the prognosis of patients with HF was determined by subgroup analysis and Kaplan-Meier analysis.

RESULTS

The study population was divided into the HF group (n = 102) and the non-HF group (n = 218). The median age of the total population was 44.5 years (31-56 years), of which 227 (70.94%) patients were male. The incidence rates of 1-year all-cause mortality, cardiac outcomes, and composite outcomes were respectively almost sixfold, fourfold, and threefold higher in the HF group than in the non-HF group (all p < 0.001). In multivariate Cox regression analysis, HF was an independent risk factor for 1-year all-cause mortality, cardiac outcomes, cerebral outcomes, and composite outcomes. The Kaplan-Meier survival curves revealed that the patients with both HF and thrombocytopenia demonstrated the worst composite outcomes than the patients of the other groups (log-rank p < 0.001). In the HF group, the platelet count was significantly associated with mortality and composite outcomes.

CONCLUSIONS

HF and preoperative platelet count are significantly associated with 1-year all-cause mortality and adverse outcomes postoperatively in IE patients. Patients with HF and thrombocytopenia have the worst short-term prognosis.

Association between platelet counts and clinical outcomes in acute fatty liver of pregnancy: A retrospective cohort study

OBJECTIVES

To investigate whether platelet counts are associated with clinical outcomes in patients with acute fatty liver of pregnancy (AFLP).

METHODS

We retrospectively analyzed 140 patients with AFLP admitted to the Third Affiliated Hospital of Guangzhou Medical University between January 2010 and August 2022. In this cohort study, we used smooth curve fitting, Kaplan-Meier analysis, and multivariable logistic regression analysis to examine the independent relationship between platelet counts and 42-day postpartum mortality in AFLP.

RESULTS

There were 140 patients with AFLP, of which 15 died and 53 (37.86%) had thrombocytopenia. The overall 42-day postpartum maternal mortality was 10.7%. We observed a U-shaped relationship between the platelet counts and 42-day postpartum mortality. Two different slopes were observed below and above the inflection point at approximately 220 × 109 /L. After adjusting for some confounders, patients with thrombocytopenia (<100 × 109 /L) were found to have increased 42-day postpartum mortality compared with middle-tertile and highest-tertile patients. Patients with thrombocytopenia had a higher 42-day postpartum mortality, and higher proportions of intensive care unit admissions, postpartum hemorrhage, and multiple organ failure (P < 0.05).

CONCLUSIONS

A U-shaped association between platelet counts and 42-day postpartum mortality was observed in patients with AFLP. Thrombocytopenia is associated with poorer adverse clinical outcomes in women with AFLP.

Hematological Toxicity of PARP Inhibitors in Metastatic Prostate Cancer Patients with Mutations of BRCA or HRR Genes: A Systematic Review and Safety Meta-analysis

BACKGROUND

PARP inhibitors (PARPis) are effective treatment options for patients with metastatic castration-resistant prostate cancer (mCRPC) as single agents or in combination with androgen receptor-targeted agents (ARTA). However, a clinically relevant adverse effect of these agents is hematological toxicity, a typical class adverse event (AE), which can lead to treatment modifications and discontinuations.

OBJECTIVE

We aimed to analyze the risk of hematological AEs, including anemia, neutropenia, and thrombocytopenia secondary to PARPi treatments in mCRPC.

PATIENTS AND METHODS

This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. We systematically searched the PubMed, EMBASE, and Cochrane databases, the American Society of Clinical Oncology (ASCO), and the European Society of Medical Oncology (ESMO) meeting abstracts for clinical trials concerning the use of PARPis, both as single agents and in combination, in patients with mCRPC. The search deadline was 30 June, 2023. We analyzed the pooled incidence of all grades of and ≥ G3 anemia, neutropenia, and thrombocytopenia. We subsequently calculated risk ratios (RRs) for all grades of and ≥ G3 AEs of PARPis versus non-PARPis from randomized clinical trials (RCTs).

RESULTS

Eleven phase 2/3 trials with olaparib, niraparib, rucaparib, and talazoparib administered as single agents or combined with ARTA were selected. Anemia was the most common all grades (38.6%) and ≥ G3 AE (24.9%). In the analysis of relative risk, six RCTs were included. The administration of PARPis significantly increased the risk of developing all grades of anemia (RR = 2.44), neutropenia (RR = 3.15), and thrombocytopenia (RR = 4.66) compared with non-PARPis. Similarly, a significant increase in the risk of ≥ G3 anemia (RR = 5.73) and thrombocytopenia (RR = 5.44), and a not significant increased risk of neutropenia (RR = 3.41), were detected.

CONCLUSIONS

In mCRPC, PARPis increase the risk of hematological toxicity compared with other treatments, both as single agents or combined with ARTA (high-quality evidence). Clinicians should be aware of this risk and the correct management, especially with the expected increased PARPis use in mCRPC.

Spatiotemporal distribution and environmental influences of severe fever with thrombocytopenia syndrome in Shandong Province, China

BACKGROUND

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. The purpose of this study was to describe the spatiotemporal distribution of SFTS and to identify its environmental influencing factors and potential high-risk areas in Shandong Province, China.

METHODS

Data on the SFTS incidence from 2010 to 2021 were collected. Spatiotemporal scan statistics were used to identify the time and area of SFTS clustering. The maximum entropy (MaxEnt) model was used to analyse environmental influences and predict high-risk areas.

RESULTS

From 2010 to 2021, a total of 5705 cases of SFTS were reported in Shandong. The number of SFTS cases increased yearly, with a peak incidence from April to October each year. Spatiotemporal scan statistics showed the existence of one most likely cluster and two secondary likely clusters in Shandong. The most likely cluster was in the eastern region, from May to October 2021. The first secondary cluster was in the central region, from May to October 2021. The second secondary cluster was in the southeastern region, from May to September 2020. The MaxEnt model showed that the mean annual wind speed, NDVI, cattle density and annual cumulative precipitation were the key factors influencing the occurrence of SFTS. The predicted risk map showed that the area of high prevalence was 28,120 km2, accounting for 18.05% of the total area of the province.

CONCLUSIONS

The spatiotemporal distribution of SFTS was heterogeneous and influenced by multidimensional environmental factors. This should be considered as a basis for delineating SFTS risk areas and developing SFTS prevention and control measures.

Evaluating the prevalence of inborn errors of immunity in adults with chronic immune thrombocytopenia or Evans syndrome

Inborn errors of immunity (IEIs) are monogenic disorders that predispose patients to immune dysregulation, autoimmunity, and infection. Autoimmune cytopenias, such as immune thrombocytopenia (ITP) and Evans syndrome (a combination of ITP and autoimmune hemolytic anemia), are increasingly recognized phenotypes of IEI. Although recent findings suggest that IEIs may commonly underlie pediatric ITP and Evans syndrome, its prevalence in adult patients with these disorders remains undefined. This study sought to estimate the prevalence of underlying IEIs among adults with persistent or chronic ITP or Evans syndrome using a next-generation sequencing panel encompassing >370 genes implicated in IEIs. Forty-four subjects were enrolled from an outpatient adult hematology clinic at a tertiary referral center in the United States, with a median age of 49 years (range, 20-83). Fourteen subjects (31.8%) had secondary ITP, including 8 (18.2%) with Evans syndrome. No cases of IEI were identified despite a high representation of subjects with a personal history of autoimmunity (45.5%) and early onset of disease (median age at diagnosis of 40 years [range, 2-77]), including 20.5% who were initially diagnosed as children. Eight subjects (18.2%) were found to be carriers of pathogenic IEI variants, which, in their heterozygous state, are not disease-causing. One case of TUBB1-related congenital thrombocytopenia was identified. Although systematic screening for IEI has been proposed for pediatric patients with Evans syndrome, findings from this real-world study suggest that inclusion of genetic testing for IEI in the routine work-up of adults with ITP and Evans syndrome has a low diagnostic yield.

Assessment of clinical spectrum of thrombocytopenia and its association with different disease states reported in Dow Diagnostic Reference and Research Lab (DDRRL)

Objectives

To evaluate the relevance of thrombocytopenia to other disease states in patients reporting at a haematology laboratory.

METHODS

The cross-sectional, retrospective study was conducted at the Dow Diagnostic Research and Reference Laboratory of the Dr Ishrat ul Ebad Khan Institute of Blood Diseases, Dow University of Health Sciences, Karachi, and comprised data from the blood bank and haematology laboratory related to patients who visited during October 2021to August 2022. Data was analysed using SPSS 26.

RESULTS

Of the 1,249 patients with mean age 38.5±19.7 years (range: 0-89 years), 79(6.3%) were aged <12 years, 592(47.4%) were aged 12-40 years and 578(46.3%) were aged >40. Most of the patients were males 793 (63.5%), and 604(48.4%) had Grade 1 thrombocytopenia. Among the females, Grade 1 thrombocytopenia was found in 246(53.9%) and Grade 2 in 140(30.7%) patients compared to 358(45.1%) and 222(28%) in males, respectively (p<0.05). Association between thrombocytopenia and diagnoses was not significant (p>0.05).

CONCLUSIONS

Thrombocytopenia was found to be strongly associated with gender.

The addition of tislelizumab to gemcitabine and cisplatin chemotherapy increases thrombocytopenia in patients with urothelial carcinoma: A single-center study based on propensity score matching

PURPOSE

Whether the addition of tislelizumab to gemcitabine and cisplatin (GC) chemotherapy increases the incidence of myelosuppression has not been well established. This study identified the risk factors for the development of myelosuppression in patients with urothelial carcinoma (UC) after receiving GC chemotherapy with or without tislelizumab.

MATERIALS AND METHODS

We enrolled 192 UC patients who received GC with or without tislelizumab at the Affiliated Hospital of Xuzhou Medical University between July 2014 and November 2022. Patient baseline characteristics were included in the statistical analyses after adjusting for previously reported risk factors affecting survival using propensity score matching (1:1). Binary logistic regression analysis was used to identify the risk factors associated with posttreatment myelosuppression.

RESULTS

A total of 192 patients were enrolled, of whom 96 were treated with tislelizumab plus gemcitabine and cisplatin (T + GC) and 96 with GC alone. The incidence of leukopenia, anemia, and thrombocytopenia of any grade was 50.0%, 70.8%, and 42.7%, respectively, in the T + GC group and 41.7%, 72.9%, and 20.8%, respectively, in the GC group. In multivariate analysis, patients aged over 70 years (OR = 2.486, 95% CI: 1.067-5.792, p = 0.035) and those who received T + GC (OR = 3.119, 95% CI: 1.576-6.173, p = 0.001) were more likely to develop thrombocytopenia. Patients aged over 70 years (OR = 3.213, 95% CI: 1.254-8.237, p = 0.015) were more likely to develop anemia, and patients with renal insufficiency (OR = 2.105, 95% CI: 1.035-4.280, p = 0.040) were more likely to develop leukopenia. Eventually, 99 (51.6%) patients with UC successfully completed all the treatment cycles.

CONCLUSIONS

This study demonstrates that the addition of tislelizumab to GC chemotherapy led to a considerable increase in the occurrence of thrombocytopenia, whereas no significant changes were observed regarding anemia or leukopenia. It is crucial to fully inform patients at increased risk for myelosuppression of potential risks and closely monitor changes in their blood routines.

Thrombocytopenia and venous thromboembolic events after BNT162b2, CoronaVac, ChAdOx1 vaccines and SARS-CoV-2 infection: a self-controlled case series study

This study assessed the association between COVID-19 vaccines, SARS-CoV-2 infection and the risk of thrombocytopenia and venous thromboembolism (VTE). This self-controlled case series study used hospital records between 1st February 2021 and 28th February 2022 linked to the national immunisation registry and COVID-19 surveillance data in Malaysia. Conditional Poisson regression was used to estimate incidence rate ratios (IRR) of events in the risk period (day 1-21 post-exposure) relative to control period with the corresponding 95% confidence interval (CI) adjusted for calendar period. We found no significant increased risk of thrombocytopenia in 1-21 days following BNT162b2, CoronaVac and ChAdOx1 vaccines while the risk was increased following SARS-CoV-2 infection (IRR 15.52, 95% CI 13.38-18.00). Similarly, vaccination with BNT162b2, CoronaVac, or ChAdOx1 was not associated with an increased risk of VTE during the 1-21 days risk period. SARS-CoV-2 infection was associated with increased risk of VTE (IRR 39.84, 95% CI 27.45-32.44). Our findings showed low event rates of thrombocytopenia and VTE following booster vaccination with comparable safety profiles between those who received homologous and heterologous booster combinations. Our findings showed the risk of thrombocytopenia and VTE was not increased after COVID-19 vaccination while the risks were substantially higher after SARS-CoV-2 infection.

HELLP syndrome at <23 weeks' gestation: a systematic literature review

OBJECTIVE

We performed a systematic review to evaluate the clinical presentation and maternal and fetal outcomes in pregnancies with early-onset HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome.

DATA SOURCES

PubMed, Ovid MEDLINE, Scopus, CINAHL, Cochrane Library, and ClinicalTrials.gov were queried from inception through January 1, 2023 with the following terms: "HELLP syndrome," "HELLP," "hemolysis, elevated liver enzymes, low platelets," "hemolysis, elevated liver enzymes, low platelets syndrome," "pre-viable," "peri-viable," "previable," "periviable," "first trimester," "second trimester," "before 23 weeks," "<23 weeks," "<23 week gestation," and "before 23 weeks gestation." We also included an additional case from our institution.

STUDY ELIGIBILITY CRITERIA

Abstracts, unpublished studies, and review articles were excluded, yielding 46 studies that met our inclusion criteria.

METHODS

Two reviewers (N.S.I. and M.H.M.) performed the study selection and subsequent data extraction independently, after which the results were reviewed together. PRISMA guidelines were followed, and our study was registered at PROSPERO (CRD42021292692).

RESULTS

A total of 55 patients had 58 pregnancies complicated by early-onset HELLP syndrome, including 3 with recurrent HELLP. The most common presenting signs/symptoms were abdominal pain (35/45; 78%), hypertension (32/49; 65%), nausea/vomiting (16/45; 36%), headache (13/45; 29%), and edema (8/45; 18%). Lactate dehydrogenase ≥600 IU/L was observed in 21 of 31 (68%) cases, whereas liver enzyme abnormalities and thrombocytopenia were reported in 48 of 51 (94%) and 50 of 54 (93%) cases, respectively. Maternal complications were encountered in 25 of 56 (45%) cases. The most common complications were hepatic (13/56; 23%), central nervous system-related (11/56; 20%), and respiratory (11/56; 20%). In 36 of 57 (63%) cases, pregnancy was terminated. Of the 21 continued pregnancies, early fetal death (at <20 weeks' gestation) was reported in 10 (48%), stillbirth in 6 (28%), and neonatal demise in 2 (10%). Living neonates were reported in 3 of 21 (14%) cases, all delivered at 23 weeks. The perinatal mortality rate was 73% (8/11). One case (2%) reported maternal death. Antiphospholipid syndrome was diagnosed in 14 of 29 (48%) cases.

CONCLUSION

Early-onset HELLP syndrome presents with symptoms similar to those observed in later gestation. Maternal complications are life-threatening, with the most common complications being hepatic, central nervous system-related, and respiratory. Fetal outcomes are poor.

Herpes simplex virus infection among neonates suspected of invasive bacterial infection: a population-based cohort study

OBJECTIVE

To estimate the incidence of neonatal herpes simplex virus (HSV) infection and the number of neonates with suspected invasive bacterial infection (IBI) needed to treat (NNT) with acyclovir to ensure prompt treatment of invasive HSV infections.

DESIGN

A nationwide population-based cohort study.

SETTING

All neonatal and paediatric emergency departments in Denmark from 1 January 2010 to 31 December 2019.

PATIENTS

Neonates aged 0-28 days with HSV infection.

MAIN OUTCOME MEASURES

The main outcome measures were incidence and NNT. The NNT was calculated based on neonates with invasive HSV infection whose onset symptoms resembled IBI and the estimated number of Danish neonates who received antibiotics for suspected IBI.

RESULTS

Fifty-four neonates with HSV infection were identified, that is, an incidence of 9 per 100 000 live births. Twenty presented with symptoms resembling IBI, all within the first 14 days of life. Of 18 (78%) neonates, 14 had elevated C reactive protein, 14 of 19 (74%) had elevated alanine aminotransferase and 11 of 17 (65%) had thrombocytopaenia. The estimated NNTs with empiric acyclovir at postnatal ages 0-3, 4-7 and 8-14 days were 1139 (95% CI 523 to 3103), 168 (95% CI 101 to 726) and 117 (95% CI 48 to 198), respectively.

CONCLUSIONS

The incidence of neonatal HSV infection was higher than in previous decades; however, the estimated NNT with empiric acyclovir was high. Therefore, we propose not to treat all neonates suspected of IBI with empiric acyclovir, as current European guidelines suggest. However, HSV should be considered in neonates with signs of infection, especially after the third postnatal day and in neonates with high alanine aminotransferases and thrombocytopaenia.

Thrombocytopenia and platelet transfusions in ICU patients: an international inception cohort study (PLOT-ICU)

PURPOSE

Thrombocytopenia (platelet count < 150 × 109/L) is common in intensive care unit (ICU) patients and is likely associated with worse outcomes. In this study we present international contemporary data on thrombocytopenia in ICU patients.

METHODS

We conducted a prospective cohort study in adult ICU patients in 52 ICUs across 10 countries. We assessed frequencies of thrombocytopenia, use of platelet transfusions and clinical outcomes including mortality. We evaluated pre-selected potential risk factors for the development of thrombocytopenia during ICU stay and associations between thrombocytopenia at ICU admission and 90-day mortality using pre-specified logistic regression analyses.

RESULTS

We analysed 1166 ICU patients; the median age was 63 years and 39.5% were female. Overall, 43.2% (95% confidence interval (CI) 40.4-46.1) had thrombocytopenia; 23.4% (20-26) had thrombocytopenia at ICU admission, and 19.8% (17.6-22.2) developed thrombocytopenia during their ICU stay. Absence of acquired immune deficiency syndrome (AIDS), non-cancer-related immune deficiency, liver failure, male sex, septic shock, and bleeding at ICU admission were associated with the development of thrombocytopenia during ICU stay. Among patients with thrombocytopenia, 22.6% received platelet transfusion(s), and 64.3% of in-ICU transfusions were prophylactic. Patients with thrombocytopenia had higher occurrences of bleeding and death, fewer days alive without the use of life-support, and fewer days alive and out of hospital. Thrombocytopenia at ICU admission was associated with 90-day mortality (adjusted odds ratio 1.7; 95% CI 1.19-2.42).

CONCLUSION

Thrombocytopenia occurred in 43% of critically ill patients and was associated with worse outcomes including increased mortality. Platelet transfusions were given to 23% of patients with thrombocytopenia and most were prophylactic.

Circulating platelets and malaria severity: two sides of the same coin among inhabitants of a tropical savannah region, Nigeria

Changes in circulating platelets during different grades of malaria are of major concerns, and its etiology is poorly understood. We appraised and evaluated the role of circulating platelets in the determination of the severity of malaria among a cohort of outpatients living in Ilorin, Nigeria. A hospital-based case-control study of outpatients visiting public health facilities within the locality voluntarily enrolled for this study. Blood samples from 1162 malaise patients were screened using routine microscopy for Plasmodium parasite species identification, and their respective circulating platelet levels were determined. Seven hundred and seventy-five individuals (775, 66.7%, p<0.001) were malaria-positive. Samples from 387 (33.3%) uninfected healthy individuals were used as controls. Individuals with uncomplicated malaria (UCM) and complicated malaria (CM) across age group were notable (p<0.05). Children ≤5 years had the highest number of individuals with CM (103, 45.2%) with a relative risk ratio of 4.005 (95% CI: 2.964-5.413). UCM (471, 40.5%) occurred more than CM (304, 26.2%) (p>0.05) across the groups. The geometric mean, 95% CI, median, and IQR of populations with malaria thrombocytopenia were higher (181, 110.94±2.207, 106.59-115.30, 118.00, and 39.00) than thrombocytosis (78, 624.64±13.131, 598.49-650.79, 623.00, and 208). Seemingly, health controls recorded insignificant morbidity with respect to platelet counts. High P. falciparum parasitemia is inversely correlated with platelet count, and its' morbidity is associated with the manifestation of several malaria pathogenesis. Thrombocytopenia is a silent pathophysiological attribute that can trigger other cofactors during severe malaria disease. Although further studies are pertinent in order to specifically clarify its relevance to clinical disease spectrum.

Thrombocytopenia as a Bleeding Risk Factor in Atrial Fibrillation and Coronary Artery Disease: Insights From the AFIRE Study

Background Thrombocytopenia poses a risk of bleeding in patients with chronic coronary syndrome after coronary intervention. However, whether thrombocytopenia also increases the bleeding risk in patients with atrial fibrillation and chronic coronary syndrome remains unclear. Methods and Results This study evaluated the AFIRE (Atrial Fibrillation and Ischemic Events With Rivaroxaban in Patients With Stable Coronary Artery Disease) trial. Thrombocytopenia was defined as platelet count <100 000/mm3 level at enrollment. Primary end points included incidence of major bleeding based on the International Society on Thrombosis and Hemostasis criterion and major adverse cardiovascular ischemic events (cardiac death, myocardial infarction, and stroke). A total of 2133 patients were classified into the thrombocytopenia (n=70) and nonthrombocytopenia (n=2063) groups. Major bleeding was significantly higher in the thrombocytopenia group than in the nonthrombocytopenia group (10.0% versus 4.1%, P=0.027). The thrombocytopenia group tended to have a higher risk of major adverse cardiovascular ischemic events (11.4% versus 6.2%, P=0.08). The bleeding incidence was significantly higher in patients with thrombocytopenia receiving combination therapy with rivaroxaban and a single antiplatelet drug (thrombocytopenia group, 14.3%, versus nonthrombocytopenia group, 5.0%; hazard ratio, 3.18 [95% CI, 1.27-7.97], P=0.014). Thrombocytopenia was an independent predictor of major bleeding (hazard ratio, 2.57 [95% CI, 1.19-5.56], P=0.017). Conclusions Among patients with atrial fibrillation and chronic coronary syndrome, thrombocytopenia was significantly associated with increased risk of major bleeding. Selecting drugs for patients with thrombocytopenia continuing antithrombotic therapy should be given special consideration. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02642419. https://www.umin.ac.jp/ctr/; Unique identifier: UMIN000016612.

[The epidemiology and pathogeny investigation of two clusters of severe fever with thrombocytopenia syndrome disease outbreaking in Henan Province, 2022]

To investigate two clusters of severe fever with thrombocytopenia syndrome virus (SFTSV) in Xinyang City, Henan Province, in 2022, and analyze their causes, transmission route, risk factors, and the characteristics of virus genetic variation. Case search and case investigation were carried out according to the case definition. Blood samples from cases, family members and neighbors and samples of biological vectors were collected for RT-PCR to detect SFTSV. The whole genome sequencing and bioinformatics analysis were performed on the collected positive samples. A total of two clustered outbreaks occurred, involving two initial cases and ten secondary cases, all of which were family recurrent cases. Among them, nine secondary cases had close contact with the blood of the initial case, and it was determined that close contact with blood was the main risk factor for the two clustered outbreaks. After genome sequencing analysis, we found that the SFTSV genotype in two cases was type A, which was closely related to previous endemic strains in Xinyang. The nucleotide sequence of the SFTSV in the case was highly homologous, with a total of nine amino acid mutation sites in the coding region. It was not ruled out that its mutation sites might have an impact on the outbreak of the epidemic.

Cytopenias in pediatric kidney transplant recipients: preceding factors and clinical consequences

BACKGROUND

Kidney trans plantation is associated with secondary complications, including the risk of developing posttransplant cytopenias. This study aimed to evaluate the characteristics, identify predictors, and assess the management and consequences of cytopenias in the pediatric kidney transplant population.

METHODS

This is a single-center retrospective analysis of 89 pediatric kidney transplant recipients. Possible factors preceding cytopenias were compared with the goal of recognizing predictors for posttransplant cytopenias. Posttransplant neutropenias were analyzed for the total study period and separately for the period beyond 6 months posttransplant (late neutropenias), to rule out confounding influences of induction and initial intensive therapy.

RESULTS

Sixty patients (67%) developed at least one episode of posttransplant cytopenia. All episodes of posttransplant thrombocytopenias were mild or moderate. Posttransplant infections and graft rejection were found to be significant predictors for thrombocytopenia (HR 6.06, 95% CI 1.6-22.9, and HR 5.82, 95% CI 1.27-26.6, respectively). A total of 30% of posttransplant neutropenias were severe (ANC ≤ 500). Pretransplant dialysis and posttransplant infections were significant predictors for late neutropenias (HR 11.2, 95% CI 1.45-86.4, and HR 3.32, 95% CI 1.46-7.57, respectively). Graft rejection occurred in 10% of patients with cytopenia, all following neutropenia, within 3 months from cytopenia appearance. In all such cases, mycophenolate mofetil dosing had been held or reduced prior to rejection.

CONCLUSIONS

Posttransplant infections are substantial contributors to developing posttransplant cytopenias. Preemptive transplantation appears to reduce risk of late neutropenia, the accompanying reduction in immunosuppressive therapy, and the ensuing risk of graft rejection. An alternative response to neutropenia, possibly using granulocyte colony stimulating factor, may diminish graft rejection. A higher resolution version of the Graphical abstract is available as Supplementary information.

Cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia in middle-income countries

BACKGROUND

Adenovirus-based COVID-19 vaccines are extensively used in low- and middle-income countries (LMICs). Remarkably, cases of cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) have rarely been reported from LMICs.

AIMS

We studied the frequency, manifestations, treatment, and outcomes of CVST-VITT in LMICs.

METHODS

We report data from an international registry on CVST after COVID-19 vaccination. VITT was classified according to the Pavord criteria. We compared CVST-VITT cases from LMICs to cases from high-income countries (HICs).

RESULTS

Until August 2022, 228 CVST cases were reported, of which 63 were from LMICs (all middle-income countries [MICs]: Brazil, China, India, Iran, Mexico, Pakistan, Turkey). Of these 63, 32 (51%) met the VITT criteria, compared to 103 of 165 (62%) from HICs. Only 5 of the 32 (16%) CVST-VITT cases from MICs had definite VITT, mostly because anti-platelet factor 4 antibodies were often not tested. The median age was 26 (interquartile range [IQR] 20-37) versus 47 (IQR 32-58) years, and the proportion of women was 25 of 32 (78%) versus 77 of 103 (75%) in MICs versus HICs, respectively. Patients from MICs were diagnosed later than patients from HICs (1/32 [3%] vs. 65/103 [63%] diagnosed before May 2021). Clinical manifestations, including intracranial hemorrhage, were largely similar as was intravenous immunoglobulin use. In-hospital mortality was lower in MICs (7/31 [23%, 95% confidence interval (CI) 11-40]) than in HICs (44/102 [43%, 95% CI 34-53], p = 0.039).

CONCLUSIONS

The number of CVST-VITT cases reported from LMICs was small despite the widespread use of adenoviral vaccines. Clinical manifestations and treatment of CVST-VITT cases were largely similar in MICs and HICs, while mortality was lower in patients from MICs.

Incidence and clinical outcomes of heparin-induced thrombocytopenia: 11 year experience in a tertiary care university hospital

Heparin-induced thrombocytopenia (HIT) is a rare immuno-mediated adverse reaction with high thrombotic and mortality risk. To evaluate incidence and outcomes of HIT cases diagnosed at a tertiary care hospital from 2007 to 2018. A retrospective study was conducted. Patients with suspected HIT underwent 4Ts score assessment and anti-heparin PF4 IgG antibodies ELISA screening test. If the latter was positive, platelet aggregation test (PAT) was performed. If the latter was positive, any form of heparin was stopped, alternative anticoagulants were started and then overlapped with warfarin. HIT incidence was calculated by dividing HIT cases by the mean yearly number of admitted patients over 11 years. Follow-up was 90 days. Among 2125 screening tests, 96 (4.5%) were positive with confirmatory PAT in 82/90 (3.8% for missing data in 6). Median age was 75; 39 patients were surgical and 51 medical. The median 4Ts score was 5. Unfractionated heparin was employed in 34 (37%). HIT incidence was 0.16/1000/patient/years (95% CI: 0.12-0.23) in surgical and 0.15/1000/patient/years (95%: 0.12-0.20) in medical patients. HIT with thrombosis (HIT-T) was observed in 31 patients (0.05/1000/patient/years 95% CI: 0.04-0.1), with venous thromboses in 25 (80%). HIT without thrombosis was observed in 59 patients (0.1/1000 patient/years; 95% CI: 0.08-0.13, twofold vs HIT-T). All cause mortality was 25.5% (95% CI: 17.6-35.4), major bleeding 7.7% (95% CI:3.2-15.3), and thromboembolic complications 3.3% (95% CI:1.1-9.3). HIT is a rare event with high mortality, despite the use of non heparin anticoagulants.

Risk factors for thrombocytopenia in patients receiving linezolid therapy: a systematic review and meta-analysis

PURPOSE

The incidence of linezolid-induced thrombocytopenia (LIT) has been reported to vary widely across studies. We performed a meta-analysis to identify the risk factors for thrombocytopenia among patients who received linezolid treatment.

METHODS

The PubMed, Embase and Cochrane Library databases were searched from inception to November 2022 to identify eligible studies. Data on the potential predictors of incidence in LIT were pooled using a random effects model. Sensitivity analyses were performed to determine the robustness of the results when significant heterogeneity was observed.

RESULTS

Forty observational studies involving 6454 patients treated with linezolid were included in the analysis. LIT was estimated to occur in 37% of patients. The following important factors were associated with the incidence of LIT: advanced age, body mass index, concurrent renal impairment or liver disease, abnormal laboratory parameters (including white blood cell count, serum creatinine, baseline platelet count, albumin, creatinine clearance rate, and estimated glomerular filtration rate), treatment duration and renal replacement therapy.

CONCLUSIONS

A variety of risk factors related to the occurrence of LIT were revealed in our analysis. Early identification of these factors could help patients improve clinical outcomes.

[Translated article] Influence of augmented renal clearance in the lower incidence of linezolid-related haematological toxicity

OBJECTIVES

Linezolid is an oxazolidin commonly related to the development of haematological toxicity, being renal clearance the major factor involved in the drug clearance. The aim of this study is to evaluate the influence of increased filtration rates in the incidence of linezolid-induced haematological toxicity by comparing augmented renal clearance (ARC) patients versus normal renal function patients.

MATERIAL AND METHODS

A retrospective, observational study was conducted on hospitalized patients treated with linezolid for 5 days or more during 2014-2019 period. Patients with a filtration rate of ≥130 mL/min versus reference patients (60-90 mL/min) were compared. Haematological toxicity was defined as a decrease of 25% in platelets, of 25% in haemoglobin, and/or 50% in neutrophils from baseline. Toxicity relevance was classified according to Common Terminology Criteria for Adverse Events v5. Incidence of haematological toxicity between groups was studied by chi-square and Fisher test. Furthermore, percentage diminution of all 3 parameters was calculated and compared by Mann-Whitney test and treatment interruption and transfusion requirements were registered.

RESULTS

30 ARC patients and 38 reference patients were included. Haematological toxicity was observed in 16.66% of ARC patients vs 44.74% of reference patients (P=.014); thrombocytopenia in 13.33% vs 36.84% (P=.051), anaemia in 3.3% vs 10.52% (P=.374) and neutropenia in 10% vs 23.68% (P=.204). Median percentage of platelets decrease in ARC patients was -10.36 (-193.33-62.03) vs 2.68 (-163.16-82.71) in reference patients (P=.333), while haemoglobin decrease was 2.50 (-12.12-25.93) vs 9.09 (-17.72-30.63) (P=.047) and neutrophils decrease was 9.14 (-73.91-76.47) vs 27.33 (-86.66-90.90) (P=.093). 10.5% of normal renal function patients reported at least 1 adverse event grade 3 or superior while 2.6% of them interrupted treatment and 5.2% had transfusion requirements. No major events or interruptions were reported in ARC patients.

CONCLUSION

Our findings suggest a lower incidence and clinical relevance of haematological toxicity in augmented renal clearance patients. Thrombocytopenia was the major event in both populations. This might be related to a lower exposure to the drug due to the higher clearance and likely lower therapeutic efficiency. These results suggest a potential benefit of therapeutic drug monitoring on high risk patients.

Thrombosis with thrombocytopenia syndrome: A database review of clinical trial and post-marketing experience with Ad26.COV2.S

BACKGROUND

Thrombosis with thrombocytopenia syndrome (TTS) is a very rare disorder described after vaccination with adenoviral vector-based COVID-19 vaccines. Co-occurring thrombosis with thrombocytopenia reported after vaccination can be a proxy for identification of TTS.

METHODS

Descriptive database review of all cases of co-occurring (within 42 days) thrombosis with thrombocytopenia in participants in Ad26.COV2.S clinical trials or recipients of Ad26.COV2.S in real-world clinical practice. Cases were retrieved from Janssens' clinical trial and Global Medical Safety databases.

RESULTS

There were 34 cases of co-occurring thrombosis with thrombocytopenia in Ad26.COV2.S recipients (46 per 100,000 person-years) and 15 after placebo (75 per 100,000 person-years) in clinical trials. Among Ad26.COV2.S recipients, mean age at the time of the event was 63 years (range 25-85), 82 % were male, mean time-to-onset 112 days (range 8-339) post-last Ad26.COV2.S dose, 26 events occurred post-dose-1, and 7 within a 28-day risk window post-vaccination. Diagnostic certainty was evaluated using Brighton Collaboration, US Centers for Disease Control and Prevention, and European Medicines Agency Pharmacovigilance Risk Assessment Committee case definitions. One case met the highest level of diagnostic certainty for all 3 definitions. There were 355 spontaneous reports of co-occurring thrombosis with thrombocytopenia in the Global Medical Safety database, 47 % males, 85 % within 28-days after vaccination. Twenty-seven cases met the highest level of diagnostic certainty for all definitions, 21 female, 19 with cerebral venous sinus thrombosis, age-range 18-68 years. Time-to-onset was 7-14 days post-vaccination in 20 cases. There were 8 fatalities.

CONCLUSION

TTS induced by Ad26.COV2.S is very rare. Most co-occurring thrombosis with thrombocytopenia does not constitute TTS.

Re-evaluation of the risk of venous thromboembolism after COVID-19 vaccination using haematological criteria

An elevated risk of venous thromboembolism (VTE) following a first dose of the ChAdOx1 adenovirus-vectored vaccine was found in a national epidemiological study in England using routine discharge diagnosis codes. Separately, the syndrome of vaccine-induced immune thrombotic thrombocytopenia (VITT) was identified using haematological criteria based on presence of thrombocytopenia, significantly elevated D-dimers and development of anti-PF4 antibodies. To re-evaluate risk estimates using haematological criteria, we obtained the haematology results for hospital admitted patients aged 18-64 years in 43 National Health Service trusts in England who were included in the national epidemiological study. Diagnoses were confirmed and haematological parameters obtained from local records without knowledge of vaccination status. The haematological parameters in patients admitted for a confirmed VTE following ChAdOx1 or BNT162b2 mRNA vaccination were then compared with those in a randomly selected 40% sample of unvaccinated patients with VTE. Overall, 12 (14%) of the 84 vaccinated cases had a diagnosis compatible with VITT, 11 after a first dose of ChAdOx1 and one after a first dose of BNT162b2. Thrombocytopenia (platelet count <150 × 109/L) occurred in 17 vaccinated (20%) and 4 (4%) of 108 unvaccinated patients, with all 6 cases of severe thrombocytopenia (<50 × 109/L) occurring within 42 days of a first dose of ChAdOx1. The attributable risk estimates for a cerebral venous thrombosis (CVT) or other VTE with thrombocytopenia after a first dose of ChAdOx1 vaccine were 2.82 and 9.62 per million doses respectively. However, elevated risks were also found after a first dose of ChAdOx1 for VTE without thrombocytopenia with relative incidences for CVT and other VTE of 2.67 (1.77-3.77) and 1.93 (1.57-2.35) respectively. While we identified a distinct population with features of VITT within 42 days of receiving ChAdOx1 vaccination, confirming current diagnostic criteria, we also found evidence of an increased risk of a VTE without thrombocytopenia after ChAdOx1 vaccine.

Prevalence and outcomes of heparin-induced thrombocytopenia in hospitalized patients with venous thromboembolic disease: Insight from national inpatient sample

OBJECTIVE

The mainstay of therapy for patients with venous thromboembolic disease (VTE) is anticoagulation. In the inpatient setting, majority of these patients are treated with heparin or low molecular weight heparin. The prevalence and outcomes of heparin-induced thrombocytopenia (HIT) in hospitalized patients with venous thromboembolic disease (VTE) is unknown.

METHODS

This nationwide study identified patients with VTE from the National Inpatient Sample database between January 2009 and December 2013. Among these patients, we compared in-hospital outcomes of patients with and without HIT using a propensity score-matching algorithm. The primary outcome was in-hospital mortality. Secondary outcomes included rates of blood transfusions, intracranial hemorrhage, gastrointestinal bleed, length of hospital stay, and total hospital charges.

RESULTS

Among 791,932 hospitalized patients with VTE, 4948 patients (0.6%) were noted to have HIT (mean age, 62.9 ±16.2 years; 50.1% female). Propensity-matched comparison showed higher rates of in-hospital mortality (11.01% vs 8.97%; P < .001) and blood transfusions (27.20% vs 20.23%; P < .001) in patients with HIT compared with those without HIT. No significant differences were noted in intracranial hemorrhage rates (0.71% vs 0.51%; P > .05), gastrointestinal bleed (2.00% vs 2.22%; P > .05), length of hospital stay (median, 6.0 days; interquartile range [IQR], 3.0-11.0 vs median, 6.0 days; IQR, 3.0-10.0 days; P > .05), and total hospital charges (median, $36,325; IQR, $17,798-$80,907 vs median, $34,808; IQR, $17,654-$75,624; P > .05).

CONCLUSIONS

This nationwide observational study showed that 0.6% of hospitalized patients with VTE in the United States have HIT. The presence of HIT was associated with higher in-hospital mortality and blood transfusion rates compared with those without HIT.

Prevalence and risk factors for severe linezolid-associated thrombocytopenia in pediatric patients: An analysis of a public database

Linezolid is widely used in various clinical settings. Studies have revealed that it may cause thrombocytopenia in adults. However, the correlation between the use of linezolid and thrombocytopenia in pediatric patients is still unclear. This study aimed to identify the impact of Linezolid on the occurrence of thrombocytopenia in children. A retrospective observational study was conducted using data on patients treated with linezolid from the Pediatric Intensive Care clinical database. Univariate and multiple logistic regression analyses were performed to identify the risk factors of linezolid-related severe thrombocytopenia. A total of 134 patients were included. The prevalence of severe thrombocytopenia was 8.96% (12/134). Univariate analysis indicated that the severe thrombocytopenia group showed significantly higher proportion of concomitant carbapenem (75% vs 44.3%; P < .05) and piperacillin/tazobactam (25% vs 6.6%; P < .05) than that of the non-severe thrombocytopenia group. Multivariate analysis also revealed that the occurrence of severe thrombocytopenia was significantly associated with concurrent use of carbapenem (odd ratio = 4.058; 95% confidence interval: 1.012-16.274; P = .048) and piperacillin/tazobactam (odd ratio = 5.335; 95% confidence interval: 1.117-25.478; P = .036). 75% of patients (9/12) developed severe thrombocytopenia within the first 7 days of linezolid use. The concomitant use of carbapenem and piperacillin/tazobactam was associated with an increased probability of severe thrombocytopenia in pediatric patients undergoing linezolid treatment. Further prospective clinical studies are required, and more detailed mechanisms of blood toxicity in pediatric patients must be investigated.

Association between Area under the Curve Estimated from Carboplatin Dose and Incidence of Severe Thrombocytopenia in Patients with Non-Hodgkin's Lymphoma on DeVIC Therapy

BACKGROUND

The degrees of adverse effects with carboplatin (CBDCA) are influenced by interindividual differences in the area under the curve (AUC), whereas renal function is not considered in the CBDCA dose design for dexamethasone, etoposide, ifosfamide, and CBDCA (DeVIC) therapy. We conducted this study to evaluate the association between the AUC and incidence of severe thrombocytopenia in patients treated with DeVIC with or without rituximab (DeVIC ± R).

METHODS

We retrospectively analyzed clinical data for 36 patients with non-Hodgkin's lymphoma who received DeVIC ± R between May 2013 and January 2021 at the National Hospital Organization Hokkaido Cancer Center. The AUC of CBDCA (AUCactual) was calculated backward using a variant of the Calvert formula.

RESULTS

The median AUCactual was 4.6 (interquartile range: 4.3-5.3) min mg/mL and AUCactual was negatively correlated with the nadir platelet count (r = -0.45; P < 0.01). Multivariate analysis showed that AUCactual ≥ 4.3 versus < 4.3 was an independent factor predictive of severe thrombocytopenia (odds ratio: 19.3, and 95% confidence interval: 1.45-258; P = 0.02).

CONCLUSION

This study suggests that the CBDCA dosing design considering renal function can reduce the risk of severe thrombocytopenia in DeVIC ± R therapy.

Analysis of fatal cases of severe fever with thrombocytopenia syndrome in Jiangsu province, China, between 2011 and 2022: A retrospective study

Introduction

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by the SFTS virus (SFTSV), which has a high fatality rate. This disease has become increasingly prevalent in recent years in Jiangsu province, with a noticeable rise in its incidence. Notably, fatal cases have also been increasing. Our study aimed to analyze the epidemiological characteristics and risk factors associated with the fatal cases of SFTS in Jiangsu province from 2011 to September 2022.

Methods

A retrospective study was performed among 698 SFTS cases during 2011-2022 in Jiangsu Province, China. Cox regression analyses were used to determine the dependent and independent risk factors that affected patient survival time. ArcGIS 10.7 was used for the visualization of the geographical distribution of the deaths from SFTS.

Results

There were 698 SFTS cases reported, with an increasing incidence, over the 12-year period. Among these cases, 43 deaths were reported. Fatal cases of SFTS were reported in 12 district counties from 2011 to 2022. Notably, most of the deaths occurred in Lishui county of Nanjing City. The median age of those who died was 69 years, with age ranges from 50 to 83 years. Multivariable Cox regression analysis showed that older age (>70) and living in Lishui county were risk factors for death from SFTS in Jiangsu province. Therefore, older adults aged over 70 years and residing in Lishui county were the high-risk group for SFTS mortality.

Discussion

Over the past 12 years, we have observed a consistent rise in the incidence of SFTS, accompanied by a relatively high case fatality rate, making it a critical public health issue. Therefore, it is urgently necessary to study the impact of meteorological factors on SFTS epidemics and devise prevention and control strategies.

Epidemiological and spatiotemporal analysis of severe fever with thrombocytopenia syndrome in Eastern China, 2011-2021

BACKGROUND

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease, which is caused by severe fever with thrombocytopenia syndrome virus (SFTSV) with high fatality. Recently, the incidence of SFTS increased obviously in Jiangsu Province. However, the systematic and complete analysis of spatiotemporal patterns and clusters coupled with epidemiological characteristics of SFTS have not been reported so far.

METHODS

Data on SFTS cases were collected during 2011-2021. The changing epidemiological characteristics of SFTS were analyzed by adopting descriptive statistical methods. GeoDa 1.18 was applied for spatial autocorrelation analysis, and SaTScan 10.0 was used to identify spatio-temporal clustering of cases. The results were visualized in ArcMap.

RESULTS

The annual incidence of SFTS increased in Jiangsu Province from 2011 to 2021. Most cases (72.4%) occurred during May and August with the obvious peak months. Elderly farmers accounted for most cases, among which both males and females were susceptible. The spatial autocorrelation and spatio-temporal clustering analysis indicated that the distribution of SFTS was not random but clustered in space and time. The most likely cluster was observed in the western region of Jiangsu Province and covered one county (Xuyi county) (Relative risk = 8.18, Log likelihood ratio = 122.645, P < 0.001) located in southwestern Jiangsu Province from January 1, 2017 to December 31, 2021. The Secondary cluster also covered one county (Lishui county) (Relative risk = 7.70, Log likelihood ratio = 94.938, P < 0.001) from January 1, 2017 to December 31, 2021.

CONCLUSIONS

The annual number of SFTS cases showed an increasing tendency in Jiangsu Province from 2011 to 2021. Our study elucidated regions with SFTS clusters by means of ArcGIS in combination with spatial analysis. The results demonstrated solid evidences for the orientation of limited sanitary resources, surveillance in high-risk regions and early warning of epidemic seasons in future prevention and control of SFTS in Jiangsu Province.

Risk factors and prognostic significance of platelet count abnormalities in children with HIV infection on antiretroviral therapy

OBJECTIVES

To establish the incidence, risk factors and correlation with survival of thrombocytopenia and thrombocytosis (T/T) among children with HIV infection (CWH).

DESIGN

A retrospective nested case control study of patients 0-18 years in five Baylor International Pediatric AIDS Initiative (BIPAI) centers in sub-Sahara Africa, 2004-2014.

METHODS

Clinical and laboratory variables including complete blood counts (CBC) were extracted from the BIPAI electronic medical record system. Incident cases of T/T were identified and frequency-matched on follow-up time with controls with normal platelets. We calculated the prevalence and incidence density of T/T and used conditional logistic regression to evaluate their association with selected clinical variables. We constructed Kaplan-Meier curves and a Cox proportional hazards model to evaluate the impact of T/T on survival.

RESULTS

Two thousand, one hundred and nine children were sampled. The incidence density of thrombocytopenia was 1 per 57.9 (95% confidence interval [CI] 50.3-66.8) CWH-years. Thrombocytopenia was higher in children with WHO Stage III/IV, lower in children on zidovudine, and had no association with use of lamivudine or nevirapine, CD4 + suppression, age, and nutrition status. Thrombocytopenia was independently associated with 2.2-fold higher mortality (95% CI 1.62-3.08). The incidence density of thrombocytosis was 1 per 11.4 (95% CI 10.7-12.1) CWH-years. Thrombocytosis was associated with higher CD4 + cell count, younger age, and use of lamivudine or nevirapine, and did not impact survival.

CONCLUSIONS

Platelet count is a clinically valuable biomarker of HIV clinical progression and mortality. Laboratory studies are necessary to elucidate the mechanisms of T/T.

Prescribing Trends of Oral Anticoagulants in US Patients With Cirrhosis and Nonvalvular Atrial Fibrillation

Background Many patients with cirrhosis have concurrent nonvalvular atrial fibrillation (NVAF). Data are lacking regarding recent oral anticoagulant (OAC) usage trends among US patients with cirrhosis and NVAF. Methods and Results Using MarketScan claims data (2012-2019), we identified patients with cirrhosis and NVAF eligible for OACs (CHA2DS2-VASc score ≥2 [men] or ≥3 [women]). We calculated the yearly proportion of patients prescribed a direct OAC (DOAC), warfarin, or no OAC. We stratified by high-risk features (decompensated cirrhosis, thrombocytopenia, coagulopathy, chronic kidney disease, or end-stage renal disease). Among 32 487 patients (mean age=71.6 years, 38.5% women, 15.1% with decompensated cirrhosis, mean CHA2DS2-VASc=4.2), 44.6% used OACs within 180 days of NVAF diagnosis, including DOACs (20.2%) or warfarin (24.4%). Compared with OAC nonusers, OAC users were less likely to have decompensated cirrhosis (18.6% versus 10.7%), thrombocytopenia (19.5% versus 12.5%), or chronic kidney disease/end-stage renal disease (15.5% versus 14.0%). Between 2012 and 2019, warfarin use decreased by 21.0% (32.0% to 11.0%), whereas DOAC use increased by 30.6% (7.4% to 38.0%), and among all DOACs between 2012 and 2019, apixaban was the most commonly prescribed (46.1%). Warfarin use decreased and DOAC use increased in all subgroups, including in compensated and decompensated cirrhosis, thrombocytopenia, coagulopathy, chronic kidney disease/end-stage renal disease, and across CHA2DS2-VASc categories. Among OAC users (2012-2019), DOAC use increased by 58.9% (18.7% to 77.6%). Among DOAC users, the greatest proportional increase was with apixaban (61.2%; P<0.001). Conclusions Among US patients with cirrhosis and NVAF, DOAC use has increased substantially and surpassed warfarin, including in decompensated cirrhosis. Nevertheless, >55% of patients remain untreated, underscoring the need for clearer treatment guidance.

Thrombocytopenia and neonatal outcomes among extremely premature infants exposed to maternal hypertension

BACKGROUND

Hypertensive disorders of pregnancy (HDP) are associated with neonatal hematological disturbances, such as thrombocytopenia. The association of HDP to platelet counts in the context of extreme prematurity, to trends of platelet counts during neonatal hospitalization, and to frequency of platelet transfusions remain to be explored.

PROCEDURE

Retrospective study of infants born at less than 29 weeks born between 2015 and 2019. Platelet counts were collected on initial complete blood count, at 2 weeks, 32 weeks post-menstrual age (PMA), 36 weeks PMA, and closest to discharge. We examined the association between HDP and platelet counts at each time point, frequency of platelet transfusions and intraventricular hemorrhage (IVH) grade 3 or more.

RESULTS

Total 296 infants were included, 43 exposed to HDP. Infants exposed had lower platelet counts at each time point, as well as a higher prevalence of platelet less than 150 × 10⁹ /L on one of the time points (32% vs. 65%, p < .001). Infants exposed to maternal hypertension were more frequently exposed to platelet transfusions (63% vs. 18%, p < .001). Mixed effect model demonstrated an association between HDP and a lower trend in platelet counts at each time point (β = -94 × 10³ /μl, p < .001). Although initial platelet count was associated with severe IVH, it was not associated to exposure to HDP.

CONCLUSION

Premature infants exposed to HDP have a higher prevalence of thrombocytopenia, increased frequency of platelet transfusion, and an altered trend in platelet counts during neonatal hospitalization.

Background rate estimations for thrombosis with thrombocytopaenia: challenges in evaluating rare safety signals following vaccination in real time during a pandemic

OBJECTIVES

During COVID-19 vaccination programmes, new safety signals have emerged for vaccines, including extremely rare cases of thrombosis with thrombocytopaenia syndrome (TTS). Background event rates before and during the pandemic are essential for contextualisation of such infrequent events. In the literature, most studies do not report an overall TTS event rate. Rather, background rates are mainly reported for subtypes of thrombotic/thromboembolic diagnoses included in the TTS clinical definition mostly by anatomical location, with reported rates for TTS subtypes varying widely. The objective of this study was to report prepandemic TTS background event rates in the general population.

METHODS

Prepandemic background TTS rates were generated via secondary data analysis using a cohort design in the IBM Truven MarketScan (now Merative MarketScan) US health insurance claims database, from 1 January 2019 to 31 December 2019. Two algorithms were applied: thrombocytopaenia occurring±7 days (algorithm 1) or occurring 1 day prior to ≤14 days after the thrombotic/thromboembolic event (algorithm 2).

RESULTS

The study population derived from the MarketScan database analysis included approximately 9.8 million adults (aged ≥18 years; mean age 45 years, 52% females). Using this study population, prepandemic background TTS incidence was estimated as 9.8-11.1 per 100 000 person-years. Event rates were higher in males and increased with age. Similar patterns were observed with both algorithms.

CONCLUSIONS

This study presents an estimate of aggregate prepandemic background TTS event rates including by type of thrombosis/thromboembolism and age group. The background event rates are dependent on the precision of capturing underlying TTS events in variable data sources, and the ability of electronic health records or insurance claims databases to reflect the TTS clinical definition. Differences between reported event rates demonstrate that estimating background event rates for rare, unprecedented safety events is methodologically challenging.

A standard dose of linezolid puts patients with hepatic impairment at risk of overexposure

PURPOSE

The purpose of this retrospective observational study conducted in patients with hepatic impairment was to assess the variability of linezolid trough concentrations, to determine the risk factors for linezolid overexposure, and to investigate the effect of linezolid overexposure on linezolid-induced thrombocytopenia.

METHODS

All enrolled patients received a standard dose (600 mg every 12 h) of linezolid and underwent therapeutic drug monitoring. The Child-Pugh-Turcotte score was used to divide patients into three groups: mild, moderate, and severe hepatic impairment. The risk factors for linezolid overexposure (C_min > 8 mg/L) and linezolid-induced thrombocytopenia were examined using logistic regression. And the Kaplan-Meier curve was used to describe the association between linezolid overexposure and linezolid-induced thrombocytopenia.

RESULTS

Seventy-seven patients were included, 37 (48.1%) of whom experienced linezolid overexposure. Patients with severe hepatic impairment had a substantially higher median C_min of linezolid than those with mild (20.7 mg/L vs 5.51 mg/L, P < 0.001) or moderate (20.7 mg/L vs 6.70 mg/L, P = 0.001) hepatic impairment. Severe hepatic impairment was significantly associated with linezolid overexposure (OR 7.037, 95%CI 1.426-34.727, P = 0.017). After linezolid treatment, linezolid-induced thrombocytopenia occurred in 32 (41.6%) patients, and C_min > 8 mg/L was a significant predictor of linezolid-induced thrombocytopenia (OR 3.024, 95%CI 1.083-8.541, P = 0.035).

CONCLUSION

Patients with hepatic impairment who received standard doses of linezolid are at greater risk of linezolid overexposure, which may lead to a higher incidence of linezolid-induced thrombocytopenia.

The risk factors for coagulation disorder of chimeric antigen receptor-T cell therapy in patients with hematological tumors: A systematic review and meta-analysis

BACKGROUND

Currently, the frequency of coagulation dysfunction associated with chimeric antigen receptor-T cell (Car-T) therapy cannot yet be determined.

OBJECTIVE

We performed a systematic review and meta-analysis to examine the prevalence of abnormal laboratory tests related to coagulation disorders in patients receiving Car-T therapy and provide a reference for future risk assessment mechanisms.

METHODS

We searched PubMed, Embase, and Web of Science for relevant studies and evaluated their quality using the methodology index of non-random research (MINORS). 2672 quotations were retrieved via systematic searches. After screening of titles, abstracts and full-text, 45 trials involving 2541 patients were ultimately included. 41 studies reported the incidence of thrombocytopenia, 8 studies reported the rate of low fibrin, 4 trials reported the rate of APTT or PT abnormalities and only 3 trials reported the incidence of venous thromboembolism (VTE). We performed a quantitative meta-analysis to explore the incidence of thrombocytopenia following Car-T treatment. The incidence of hypofibrinogenemia, VTE, and abnormal APTT or PT was only qualitatively assessed, as fewer reports were included in this study.

RESULTS

The overall incidence of thrombocytopenia associated with Car-T therapy was 45.8% (95%[CI], 0.384-0.533). The highest rates of thrombocytopenia occurred in patients with multiple myeloma (60.1%, 95%[CI], 0.507-0.688) and aged between 18 to 60 (50%, 95%[CI], 0.367-0.633). There was greater prevalence of thrombocytopenia in BCMA-Car-T therapy of 58.7% (95%[CI], 0.482-0.685). Thrombocytopenia occurred most frequently in Car-T patients treated with a dosage of 1 × 105-1 × 106 cell/kg, at a rate of 66.2% (95%[CI], 0.561-0.749).

CONCLUSION

Overall, 45.8 percent of patients receiving Car-T treatment suffered from thrombocytopenia. Multiple myeloma patients, ages between 18-60, a dose of 1 × 105-1 × 106 cell/kg and BCMA-Car-T therapy are all considered high-risk factors.

Efficacy and safety of endostar combined with cisplatin in treatment of non-small cell lung cancer with malignant pleural effusion: A meta-analysis

BACKGROUND

Although there are new treatments for non-small cell lung cancer with malignant pleural effusion, these therapies are prone to recurrent pleural effusion and poor in efficacy. And recombinant human endostatin is a new type of anti-tumor angiogenesis drug independently developed in my country. It has the effect of inhibiting tumor angiogenesis, inhibiting tumor proliferation and differentiation, and effectively inhibiting the formation and recurrence of malignant pleural effusion. Therefore, this study is aim to systematically review the efficacy and safety of intrapleural injection of endostar combined with cisplatin in the treatment of non-small cell lung cancer (NSCLC) with malignant pleural effusion.

METHODS

Databases including Cochrane Library, PubMed, CBM, Embase, CNKI, and WanFang Data were searched to collect randomized controlled trials about endostar combined with cisplatin for NSCLC with malignant pleural effusion from inception to April 2022. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias in included studies. Finally, the meta-analysis was made by using RevMan 5.4.1 software.

RESULTS

A total of 11 randomized controlled trials involving 814 patients were finally included. The results of the meta-analysis showed that: The overall response rate and the improvement rate of quality of life in the endostar combined with cisplatin group were higher than that of the cisplatin alone group (relative risk = 1.58, 95% confidence interval = 1.42-1.76, P < .00001; relative risk = 1.63, 95% confidence interval = 1.38-1.93, P < .00001, respectively). Meanwhile, there were no significant differences between the 2 groups in the incidence of gastrointestinal reaction, the incidence of leucopenia, the incidence of thrombocytopenia, and the incidence of hypodynamia (all P values > .05).

CONCLUSION

Compared with cisplatin, intrapleural injection of endostar combined with cisplatin could improve the overall response rate and the quality of life of NSCLC patients with malignant pleural effusion. Due to the limited quality and quantity of included studies, more high-quality studies are needed to verify the above conclusion.

Clinical and Laboratory Profile of Dengue in Kashmir Valley

BACKGROUND

As majority of cases of dengue are associated with thrombocytopenia, it is indispensable to study clinical presentation, biochemical parameters and outcome of dengue fever in a population known with low platelet count.

METHODOLOGY

A prospective observational study was conducted from September 2016 to August 2017that included forty NS-1 antigen (IgM) Dengue positive patients. Clinical features, laboratory parameters and outcome of dengue patients were noted.

RESULTS

All the patients had travel history outside the valley into the neighbouring state. Most patients (70%) had duration of stay between 21-30 days in dengue prevalent areas before catching the illness. Duration of symptoms was between 4-9 days in majority of patients (92.5%). Most patients (85%) presented in months of September to November. The three most common symptoms were fever (100%), chills (92.5%) and headache (80%). The most common laboratory features were thrombocytopenia (97.5%), leukopenia (87.5%), transaminitis (87.5%) and raised LDH (32.5%). One patient developed Dengue Hemorrhagic Fever (DHF). All patients recovered completely.

CONCLUSION

DF in Kashmir is seen exclusively in travellers to other states especially in the monsoon season.DF in Kashmiri patients has a favourable outcome despite low baseline platelet count. DHF is uncommon in Kashmiri population.

Clinical features and epidemiology of severe fever with thrombocytopenia syndrome in dogs in the Republic of Korea: an observational study (2019-2020)

Severe fever with thrombocytopenia syndrome (SFTS) is a zoonotic disease with a high mortality rate for humans and cats. The clinical course and prognosis of SFTS in dogs remains unclear. In the present study, we investigated the clinical and epidemiological characteristics of SFTS virus (SFTSV) infection in dogs. All evaluated dogs exhibited an acute course and symptoms including fever (57.1%), anorexia (57.1%), depression (42.9%), and vomiting (35.7%). Thrombocytopenia was present in 45.5% of dogs, while jaundice was not observed. C-reactive protein, alanine transaminase, and alkaline phosphatase were elevated in some cases. Viral clearance occurred within 6 to 26 days. Phylogenetic analysis revealed that the SFTSV sequences were consistent with viruses circulating in the Republic of Korea. As dogs often live in close contact with humans, awareness of the clinical and epidemiological features of SFTS in dogs is crucial. Further large-scale studies are necessary to investigate SFTSV infection in dogs.