Platelet count and aging

The clinical value of peripheral biogenic amine metabolites in early-treated phenylketonuria

BACKGROUND

Brain monoamine depletion is a well-established biochemical consequence of phenylketonuria (PKU). Similar alterations are expected in the peripheral biogenic amines (PBA), which share the same metabolic pathway with the brain. The present cross-sectional study explored the potential prognostic value of PBA by examining their relationship with blood Phe and clinical outcomes in early-treated adult PKU patients (ETPKU).

METHOD

53 ETPKU (age 27.14 ± 8.22 years; 35 female) and 60 age-matched control subjects (age 43 ± 13 years; 43 female) were enrolled in the study. A UPLC-ESI-MS/MS-based method was developed to assess 5-hydroxytryptophan (5-HTP), serotonin (5-HT), 5-hydroxyhyndolacetic acid (5-HIAA), and 3-O-methyldopa (3-OMD) in different blood-derived matrices. Life-long Index of Dietary Control (IDC), concurrent Phe, and Tyr were other parameters included in the analysis. Clinical outcome measures included IQ, executive functions (BRIEF), and psychiatric morbidity (CBCL/ASR and DSM-5-TR).

RESULTS

5-HTP, 5-HIAA, and 3-OMD were significantly lower in PKU patients than in controls. 5-HIAA and 3-OMD were negatively correlated with concurrent Phe levels. Concerning outcome measures, IDC influenced IQ and BRIEF-Shift subscale, 5-HIAA BRIEF-Emotional Control, 3-OMD BRIEF-Initiate subscale, and Tyr BRIEF-Control subscale. In contrast, concurrent plasma Phe did not affect any outcome measures.

CONCLUSION

While confirming the negative influence of Phe on PBA in adult ETPKU, mimicking what happens in the brain, we also found an effect of PBA depletion on clinical outcome measures independent of Phe level. This suggests that PBA could serve as new candidate biomarkers for treatment monitoring in adult ETPKU patients.

Association of high mobility group box 1 (HMGB1) levels with donor's age, sex and ABO blood group in single-donor apheresis platelet concentrates

BACKGROUND AND OBJECTIVES

High mobility group box 1 (HMGB1) is a nuclear protein expressed by various cell types and recognized as a damage-associated molecular pattern (DAMP). DAMPs play a pivotal role in driving inflammatory responses. Platelet-derived HMGB1 has been associated with severe adverse reactions following platelet concentrate transfusions, underscoring its clinical relevance. This study investigated whether HMGB1 levels in single-donor apheresis platelet concentrates (SDA-PCs) are influenced by routinely documented donor characteristics, such as age, sex and ABO blood group.

MATERIALS AND METHODS

We analysed HMGB1 levels in 190 unpaired SDA-PC units. Donor characteristics, that is, age, sex and ABO blood group were obtained from routine records and examined for associations with HMGB1 levels.

RESULTS

HMGB1 levels showed no significant correlation with donor age or ABO blood group. However, levels were modestly lower in SDA-PC units derived from female donors compared to male donors.

CONCLUSION

These findings reveal donor-specific variability in HMGB1 levels, particularly regarding donor sex, and underscore the need to systematically document donor demographic and biological characteristics during blood donation. Such data could enhance our understanding of donor-related factors influencing transfusion outcomes.

Lower albumin levels are associated with 1-year mortality in older patients hospitalized for acute heart failure: THE ALBIMED-HF study

Hypoalbuminemia (i.e., albumin levels ≤ 3.5 g/dL) is a negative prognostic marker in several conditions, including acute heart failure (AHF). Hypoalbuminemia is common in patients hospitalized in Internal Medicine (IM) divisions. However, its role in predicting long-term mortality in AHF patients hospitalized in this setting is not clear. In THE ALBIMED-HF study, all patients hospitalized for AHF in the First Division of Internal Medicine at Ospedale di Circolo and Fondazione Macchi (ASST Sette Laghi, Varese, Italy) between January 1st and December 31st 2022 were retrospectively included. Clinical information was retrieved from patient electronic medical records. Four hundred and ninety-eight patients were considered for the present study (median age 85 [78-89] years). Median Charlson Comorbidity Index was 6 [5-7]. Heart failure (HF) with preserved ejection fraction was found in 40.6% of patients (N = 202/498). Median albumin levels were 3.2 [2.8-3.5] g/dL and hypoalbuminemia was recorded in 76.5% of patients (N = 381/498). At 12 months, 221 out of 498 patients (44.4%) died, and mortality was significantly higher in patients with hypoalbuminemia than in those without (N = 185/381 [48.6%] vs. N = 36/117 [30.8%], p < 0.001). Patients who died within 12 months were older, suffered more frequently from chronic kidney disease and active cancer, and exhibited higher C-reactive protein levels. At the multivariable analysis, hypoalbuminemia was independently associated with 12-month all-cause mortality (HR 2.41, 95% confidence interval 1.20-4.83). Hypoalbuminemia was independently associated with 12-month all-cause mortality in older patients with multiple comorbidities hospitalized for AHF in an IM division.

Analysis of Sirolimus Blood Concentration and Influencing Factors in Pediatric Patients: Implications for Individualized Drug Therapy

BACKGROUND AND OBJECTIVE

The purpose of this study is to investigate the status of blood concentration of sirolimus (SRL), explore the factors influencing SRL drug blood concentration, and provide guidance for the appropriate utilization of clinical medications.

METHODS

A single-center retrospective cohort study encompassed 1535 blood drug concentration observations obtained from 249 children from August 2018 to June 2023. Participants were categorized into four groups (A, B, C, and D) on the basis of their blood concentration levels at various time intervals. The analysis focused on identifying the factors that influenced blood concentration in the short- and long-term posttreatment. The primary endpoint was factors affecting the sirolimus blood concentration. The effect of physiopathological indicators on the corrected blood drug concentration (C/D value) was analyzed to avoid the effect of differences in the dose of SRL used in patients on SRL blood concentrations. The multiple linear regression model was used to examine the impact of factors influencing pharmacokinetics and pharmacodynamics on the C/D.

RESULTS

Analysis of SRL blood concentration monitoring indicated that a majority (60.43%) of patients demonstrated a trough sirolimus concentration (C0) below the level of the recommended threshold of 5 ng/mL, while approximately 17.7% of patients exceeded 15 ng/mL. The results indicated a noteworthy association between weight and body surface area (BSA) and the C/D of SRL in groups A, B, and D (P < 0.05). Additionally, aspartate transaminase (AST), alanine aminotransferase (ALT), and albumin (ALB) in group A; ALB in group B; and platelet count (PLT) in group C demonstrated a statistically significant correlation with the C/D of SRL (P < 0.05).

CONCLUSIONS

Clinicians should optimize medication plans by considering the child's weight, BSA, ALT, AST, PLT, ALB, and relevant factors. These findings may serve as a valuable resource for clinicians.

Platelet life cycle during aging: function, production and clearance

Platelets are important players in hemostasis. Alterations in platelet number and/or function lead to life-threatening conditions like thrombosis, myocardial infarction and stroke. During aging, changes at the cellular, organ and systemic level occur that affect platelet counts, platelet functionality, the expression of platelet surface receptors, clearance markers as well as their interactions with immune cells. Understanding how these changes influence platelets can help to prevent the alterations of hemostasis and thrombosis we observe in the elderly. In this review, we highlight the respective changes at important sites of the platelet life cycle: bone marrow, liver and spleen, but also show how alterations in immunity contribute. We point out the necessity for further research on age-related systemic alterations in these systems and their interplay with platelets to better understand the complex processes that cause alterations in the platelet life cycle during aging.

Platelet changes and bleeding symptoms in children, adolescents, and adults with 22q11.2 deletion syndrome

BACKGROUND

The deletion region of 22q11.2 deletion syndrome (22q11.2DS) contains a gene encoding glycoprotein Ibβ (GPIbβ), which is required to express the GPIb/IX/V complex on the platelet surface. Therefore, patients with 22q11.2DS may have congenital platelet disorders. However, information is limited on platelets and bleeding symptoms. In this study, we investigated clinical information, including bleeding symptoms, platelet counts, and GPIb expression levels in children and adolescents/adults with 22q11.2DS.

PROCEDURE

Thirty-two patients with 22q11.2DS were enrolled in a prospective cohort study between 2022 and 2023 at outpatient clinics within our institute.

RESULTS

The median platelet counts in adolescents/adults with 22q11.2DS were significantly lower than those in children (p < .0001). A gradual decrease was found along with increasing age (p = .0006). Values of median GPIb expression on platelet surfaces (66% in children and 70% in adolescents/adults) were significantly lower than those in healthy controls (p < .0001 and p = .0002). Bleeding symptoms included surgery-related bleeding (52%), purpura (31%), and epistaxis (22%); most of them were minor. The median International Society on Thrombosis and Hemostasis bleeding assessment tool score was not significantly different between children and adolescents/adults (p = .2311).

CONCLUSION

Although there was an age-related decrease in platelet count and a disease-related decrease in GPIb expression, no difference in bleeding symptoms was found between children and adolescents/adults. 22q11.2DS overall had minor bleeding symptoms in daily life, and the disease had little effect on spontaneous bleeding. However, some patients had major bleeding events; further accumulation of data on hemostasis during surgery and trauma is required.

Cross-sectional screening for inflammation in tinnitus with near-normal hearing

Tinnitus is the perception of sound without an external stimulus. Recently, inflammation has been implicated in the pathophysiology of tinnitus. In tinnitus animal models, cytokine levels are increased throughout the whole auditory pathway, and microglia and astrocytes are activated. However, only a few human studies on inflammation in tinnitus were conducted, which generally did not account for confounders such as hearing loss, anxiety and depression. The current study therefore aimed to evaluate the association between inflammation and tinnitus specifically in participants with (near-)normal hearing and without signs of anxiety or depression. In this cross-sectional study, fifty tinnitus participants and fifty healthy controls completed a tinnitus questionnaire and underwent audiometric testing. Complete blood count measures were determined in blood plasma, as well as cytokine concentrations by using the enzyme-linked immunosorbent assay (ELISA) technique. Platelet count and cytokine concentrations of IL-10 and IFN-γ were lower in participants with tinnitus compared to controls, and male sex, lower MCV, lower platelet count, and lower IL-10 and IFN-γ concentrations were significant predictors of tinnitus presence. The current study shows that inflammatory parameters are altered in tinnitus patients after exclusion of important confounders such as hearing loss, anxiety, depression, and inflammatory diseases.

Benefits of Quercetin on Glycated Hemoglobin, Blood Pressure, PiKo-6 Readings, Night-Time Sleep, Anxiety, and Quality of Life in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Trial

Background: Diabetes is a rapidly growing global morbidity issue with high prevalence, and the associated dysglycemia leads to complications. Patients with type 2 diabetes mellitus (T2DM) often experience elevated anxiety levels, affecting their quality of life and diabetes management. This study investigated quercetin, a nutraceutical and potential senolytic with antioxidant activity, to detect its possible positive effect on the bio-clinical measurements and routine health of patients with T2DM. Methods: This prospective randomized controlled trial (RCT) investigated the clinical usefulness of quercetin in patients with T2DM receiving non-insulin medications. One hundred participants were stratified by age and sex (1:1) and randomized to control (n = 50) or intervention (n = 50) groups. The control received standard care only, while the intervention received 500 mg quercetin daily for 12 weeks, followed by an 8-week washout and a final consecutive 12-week supplementation period (total: 32 weeks), as adjunct to their usual care. Comprehensive health assessments, including blood analyses, were conducted at baseline and study termination. Quality of life and anxiety were assessed using the 36-item Short Form Health Survey (SF-36) and Short Anxiety Screening Test (SAST-10). Results: Eighty-eight patients with T2DM concluded the trial. Compared with the control, glycated hemoglobin (HbA1c) levels showed a significant decrease (Δ%-change: -4.0% vs. 0.1%, p = 0.011). Quercetin also significantly improved PiKo-6 readings (FEV1: 5.6% vs. -1.5%, p = 0.002), systolic blood pressure (-5.0% vs. -0.2%, p = 0.029), night-time sleep (11.6% vs. -7.3%, p < 0.001), anxiety levels (SAST-10) (-26.2% vs. 3.3%, p < 0.001), and quality of life (SF-36) (both physical and mental components, p < 0.001). Conclusions: Based on the current open-label study, quercetin appears to be a promising supplement for T2DM, providing lifestyle and care support. Further research is warranted to shift this potential from clinical usefulness and feasibility to multidisciplinary evidence.

A Systematic Review on Autism and Hyperserotonemia: State-of-the-Art, Limitations, and Future Directions

Hyperserotonemia is one of the most studied endophenotypes in autism spectrum disorder (ASD), but there are still no unequivocal results about its causes or biological and behavioral outcomes. This systematic review summarizes the studies investigating the relationship between blood serotonin (5-HT) levels and ASD, comparing diagnostic tools, analytical methods, and clinical outcomes. A literature search on peripheral 5-HT levels and ASD was conducted. In total, 1104 publications were screened, of which 113 entered the present systematic review. Of these, 59 articles reported hyperserotonemia in subjects with ASD, and 26 presented correlations between 5-HT levels and ASD-core clinical outcomes. The 5-HT levels are increased in about half, and correlations between hyperserotonemia and clinical outcomes are detected in a quarter of the studies. The present research highlights a large amount of heterogeneity in this field, ranging from the characterization of ASD and control groups to diagnostic and clinical assessments, from blood sampling procedures to analytical methods, allowing us to delineate critical topics for future studies.

Normal Clinical Laboratory Ranges by Age and Sex, and Impact on Study Screening Outcomes in Rural Mali

The interpretation of a laboratory test result requires an appropriate reference range established in healthy subjects, and normal ranges may vary by factors such as geographic region, sex, and age. We examined hematological and clinical chemistry parameters in healthy residents at two rural vaccine trial sites: Bancoumana and Doneguebougou in Mali, West Africa. During screening of clinical studies in 2018 and 2019, peripheral blood samples from 1,192 apparently healthy individuals age 6 months to 82 years were analyzed at a laboratory accredited by the College of American Pathologists for a complete blood count, and creatinine and/or alanine aminotransferase levels. Based on manufacturers' reference range values, which are currently used in Malian clinical laboratories, abnormal values were common in this healthy population. In fact, 30.4% of adult participants had abnormal neutrophil levels and 19.8% had abnormal hemoglobin levels. Differences by sex were observed in those who were older, but not in those younger than 10 years, for several parameters, including hemoglobin, platelet, and absolute neutrophil counts in hematology, and creatinine in biochemistry. The site-specific reference intervals we report can be used in malaria vaccine clinical trials and other interventional studies, as well as in routine clinical care, to identify abnormalities in hematological and biochemical parameters among healthy Malian trial participants.

Safety of Mechanical Thrombectomy for Acute Ischemic Stroke in Patients with Thrombocytopenia

BACKGROUND AND AIM

The impact of low platelet count on outcomes in patients with Acute Ischemic Stroke (AIS) undergoing Mechanical Thrombectomy (MT) is still unclear. In this study we have further explored the effect of thrombocytopenia on the safety and efficacy of MT in patients with anterior circulation Large Vessel Occlusion (LVO) stroke.

MATERIALS AND METHODS

Patients with AIS who underwent MT at our center between June 2015 and November 2021 were examined. Based on the platelet count recorded on admission patients were divided into two groups: those with thrombocytopenia (<150 × 109/L) and those without thrombocytopenia (≥ 150 × 109/L). Symptomatic Intracranial Hemorrhage (sICH) was the primary safety outcome. The efficacy outcome was functional independence defined as a 90-day modified Rankin Scale (mRS) score of 0-2. Multivariate logistic regression models were used to determine the risk factors for post-procedure sICH and 90-day functional outcomes.

RESULTS

Among 302 patients included in the study, thrombocytopenia was detected in 111 (36.8%) cases. Univariate analysis showed age, the proportion of atrial fibrillation, the rates of sICH, 90-day poor outcomes, and mortality to be higher in patients with thrombocytopenia (all p <0.05). Multivariable analysis showed thrombocytopenia to be independently associated with a higher rate of sICH (OR 2.022, 95% CI 1.074-3.807, p =0.029) however, thrombocytopenia did not affect the 90-day functional outcomes (OR 1.045, 95%CI 0.490-2.230, p =0.909) and mortality (OR 1.389, 95% CI 0.467- 4.130 p = 0.554).

CONCLUSION

Thrombocytopenia may increase the risk of sICH but not affect the 90-day functional outcomes and mortality in patients with AIS treated with MT.

Comparison of percutaneous ablation and hepatectomy for liver metastasis: A single center retrospective study

AIM

To investigate the current treatment for liver metastasis and clarify the indications for percutaneous thermal ablation for liver metastasis.

METHODS

Ninety-two patients were enrolled and retrospectively analyzed. The patients underwent hepatectomy and/or percutaneous thermal ablation for liver metastases between January 2012 and December 2018. Twenty-six patients who underwent ablation treatment and seven patients who underwent both ablation and hepatectomy were included in the ablation treatment group (group A). We compared these patients with 59 patients who underwent hepatectomy only (group H). Subgroup analyses were performed between ablation (group AC) for colorectal liver metastasis and hepatectomy (group HC) for colorectal liver metastasis in 17 and 53 patients, respectively.

RESULTS

The percentage of liver metastases other than colorectal cancer in group A was higher than that in the group H. Maximum tumor size in group A was significantly smaller than that in group H. Similarly, the patients in group AC were significantly older and demonstrated higher total bilirubin, lower serum albumin, and lower platelet counts than those in group HC. Overall survival was poorer in the AC group than that in the HC group. However, no differences were observed at metastasis ≤2 cm in size.

CONCLUSIONS

Percutaneous thermal ablation was performed for many cancer types than hepatectomy. It is performed in elderly patients. We suggested that ablation for colorectal liver metastasis sized ≤2 cm is a suitable indication.

Monitoring platelet function in marine mammals: Intracellular Ca2+ mobilization as a biomarker of platelet activation

Platelet functionality plays a crucial role in marine mammals. Alterations in platelet function can result from stress, pathologies, or exposure to xenobiotics, among others. The early detection of platelet function abnormalities is essential in these species to prevent advanced pathology and mitigate potential risks. Our main objective was to establish a range of physiological values of platelet function in bottlenose dolphins (Tursiops truncatus), beluga whales (Delphinapterus leucas), sea lions (Otaria flavescens) and walruses (Odobenus rosmarus). Intraplatelet Ca2+ mobilization using adenosine diphosphate (ADP) as a platelet agonist was used as a platelet function biomarker, adapting the methodology previously described by us in dolphins (Felipo-Benavent et al., 2022) to the rest of the species. The assay was also adapted to a seal (Phoca vitulina). Numerical indicators of intraplatelet Ca2+ mobilization kinetics were established, and statistical analyses were performed to compare the effects of species, sex, age, aquarium and species. Significant differences were observed between species, being the platelets of the sea lions the more reactive to the agonist. This work demonstrates the usefulness of this assay in the diagnosis or monitoring of animals with hemostatic diseases, showing two clinical cases in which intraplatelet calcium mobilization values were altered in marine mammals suffering haemorrhages. This assay may also serve as a means to monitor environmental changes and their potential impact on the health of marine mammal populations.

The opposing effects of two gene defects in STX11 and SLP76 on the disease in a patient with an inborn error of immunity

BACKGROUND

Inborn errors of immunity are mostly monogenic. However, disease phenotype and outcome may be modified by the coexistence of a second gene defect.

OBJECTIVE

We sought to identify the genetic basis of the disease in a patient who experienced bleeding episodes, pancytopenia, hepatosplenomegaly, and recurrent pneumonia that resulted in death.

METHODS

Genetic analysis was done using next-generation sequencing. Protein expression and phosphorylation were determined by immunoblotting. T-cell proliferation and F-actin levels were studied by flow cytometry.

RESULTS

The patient harbored 2 homozygous deletions in STX11 (c.369_370del, c.374_376del; p.V124fs60∗) previously associated with familial hemophagocytic lymphohistiocytosis and a novel homozygous missense variant in SLP76 (c.767C>T; p.T256I) that resulted in an approximately 85% decrease in SLP76 levels and absent T-cell proliferation. The patient's heterozygous family members showed an approximately 50% decrease in SLP76 levels but normal immune function. SLP76-deficient J14 Jurkat cells did not express SLP76 and had decreased extracellular signal-regulated kinase signaling, basal F-actin levels, and polymerization following T-cell receptor stimulation. Reconstitution of J14 cells with T256I mutant SLP76 resulted in low protein expression and abnormal extracellular signal-regulated kinase phosphorylation and F-actin polymerization after T-cell receptor activation compared with normal expression and J14 function when wild-type SLP76 was introduced.

CONCLUSIONS

The hypomorphic mutation in SLP76 tones down the hyperinflammation due to STX11 deletion, resulting in a combined immunodeficiency that overshadows the hemophagocytic lymphohistiocytosis phenotype. To our knowledge, this study represents the first report of the opposing effects of 2 gene defects on the disease in a patient with an inborn error of immunity.

Time- and distance-resolved robotic imaging of fluid flow in vertical microfluidic strips: a new technique for quantitative, multiparameter measurement of global haemostasis

Measuring the complex processes of blood coagulation, haemostasis and thrombosis that are central to cardiovascular health and disease typically requires a choice between high-resolution low-throughput laboratory assays, or simpler less quantitative tests. We propose combining mass-produced microfluidic devices with open-source robotic instrumentation to enable rapid development of affordable and portable, yet high-throughput and performance haematological testing. A time- and distance-resolved fluid flow analysis by Raspberry Pi imaging integrated with controlled sample addition and illumination, enabled simultaneous tracking of capillary rise in 120 individual capillaries (∼160, 200 or 270 μm internal diameter), in 12 parallel disposable devices. We found time-resolved tracking of capillary rise in each individual microcapillary provides quantitative information about fluid properties and most importantly enables quantitation of dynamic changes in these properties following stimulation. Fluid properties were derived from flow kinetics using a pressure balance model validated with glycerol-water mixtures and blood components. Time-resolved imaging revealed fluid properties that were harder to determine from a single endpoint image or equilibrium analysis alone. Surprisingly, instantaneous superficial fluid velocity during capillary rise was found to be largely independent of capillary diameter at initial time points. We tested if blood function could be measured dynamically by stimulating blood with thrombin to trigger activation of global haemostasis. Thrombin stimulation slowed vertical fluid velocity consistent with a dynamic increase in viscosity. The dynamics were concentration-dependent, with highest doses reducing flow velocity faster (within 10 s) than lower doses (10-30 s). This open-source imaging instrumentation expands the capability of affordable microfluidic devices for haematological testing, towards high-throughput multi-parameter blood analysis needed to understand and improve cardiovascular health.

aMAP Score and Its Combination With Liver Stiffness Measurement Accurately Assess Liver Fibrosis in Chronic Hepatitis B Patients

BACKGROUND & AIMS

The changes in liver stiffness measurement (LSM) are unreliable to estimate regression of fibrosis during antiviral treatment for chronic hepatitis B (CHB) patients. The age-male-albumin-bilirubin-platelets score (aMAP), as an accurate hepatocellular carcinoma risk score, may reflect the liver fibrosis stage. Here, we aimed to evaluate the performance of aMAP for diagnosing liver fibrosis in CHB patients with or without treatment.

METHODS

A total of 2053 patients from 2 real-world cohorts and 2 multicentric randomized controlled trials in China were enrolled, among which 2053 CHB patients were included in the cross-sectional analysis, and 889 CHB patients with paired liver biopsies before and after 72 or 104 weeks of treatment were included in the longitudinal analysis.

RESULTS

In the cross-sectional analysis, the areas under the receiver operating characteristic curve of aMAP in diagnosing cirrhosis and advanced fibrosis were 0.788 and 0.757, which were comparable with or significantly higher than those of the fibrosis index based on 4 factors and the aspartate aminotransferase-platelet ratio. The stepwise approach using aMAP and LSM further improved performance in detecting cirrhosis and advanced fibrosis with the smallest uncertainty area (29.7% and 46.2%, respectively) and high accuracy (82.3% and 79.8%, respectively). In the longitudinal analysis, we established a novel model (aMAP-LSM model) by calculating aMAP and LSM results before and after treatment, which had satisfactory performance in diagnosing cirrhosis and advanced fibrosis after treatment (area under the receiver operating characteristic curve, 0.839 and 0.840, respectively), especially for those with a significant decrease in LSM after treatment (vs LSM alone, 0.828 vs 0.748; P < .001 [cirrhosis]; 0.825 vs 0.750; P < .001 [advanced fibrosis]).

CONCLUSIONS

The aMAP score is a promising noninvasive tool for diagnosing fibrosis in CHB patients. The aMAP-LSM model could accurately estimate fibrosis stage for treated CHB patients.

Psychological toxicity in classical hematology

Although considered "benign," mild blood count abnormalities, genetic factors imparting inconsequential thrombotic risk, and low-risk premalignant blood disorders can have significant psychological and financial impact on our patients. Several studies have demonstrated that patients with noncancerous conditions have increased levels of anxiety with distress similar to those with malignancy. Additionally, referral to a classical hematologist can be a daunting process for many patients due to uncertainties surrounding the reason for referral or misconstrued beliefs in a cancer diagnosis ascribed to the pairing of oncology and hematology in medical practice. If not properly triaged, incidental laboratory abnormalities can trigger extensive and costly evaluation. These challenges are compounded by a lack of consensus guidance and generalizability of modern reference ranges that do not adequately account for common influencing factors. Although often benign, incidental hematologic findings can lead to emotional suffering and careful consideration of the potential psychological and financial duress imparted to an individual must be considered. In this article, we will review the current literature describing the psychological effect of some commonly known hematologic conditions, identify benign causes for variations in hematologic laboratory values, and provide recommendations to reduce psychological toxicity as it pertains to hematologic testing.

Clinical experience with glycerol phenylbutyrate in 20 patients with urea cycle disorders at a UK paediatric centre

In urea cycle disorders (UCDs) ammonia scavenger drugs, usually sodium-based, have been the mainstay of treatment. Increasingly, glycerol phenylbutyrate (GPB, Ravicti®) is being used but scant real-world data exist regarding clinical outcomes. A retrospective study of UCD patients initiated on or switched to GPB was performed at a UK centre. Data on population characteristics, treatment aspects, laboratory measurements, and clinical outcomes were collected before and after patients started GPB with a sub-group analysis undertaken for patients with ≥12 months of data before and after starting GPB. UCDs included arginosuccinate synthetase deficiency (n = 8), arginosuccinate lyase deficiency (n = 6), ornithine carbamoyltransferase deficiency (n = 3), and carbamoyl phosphate synthetase 1 deficiency (n = 3). In the sub-group analysis (n = 11), GPB resulted in lower plasma ammonia (31 vs. 41 μmol/L, p = 0.037), glutamine (670 vs. 838 μmol/L, p = 0.002), annualised hyperammonaemic episodes (0.2 vs. 1.9, p = 0.020), hospitalisations (0.5 vs. 2.2, p = 0.010), and hyperammonaemic episodes resulting in hospitalisation (0.2 vs. 1.6, p = 0.035) reflecting changes seen in the whole group. Overall, patients exposed to sodium and propylene glycol levels above UK daily limits reduced by 78% and 83% respectively. Mean levels of branched chain amino acids, haemoglobin, and white cell count were unchanged. Two adverse drug reactions (pancytopenia, fatigue/appetite loss) resolved without GPB discontinuation. Patients/families preferred GPB for its lower volume, greater palatability and easier administration. GPB appeared to improve biochemical measures and clinical outcomes. The causes are multi-factorial and are likely to include prolonged action of GPB and its good tolerability, even at higher doses, facilitating tighter control of ammonia.

Ontogenesis of functional platelet subpopulations from preterm and term neonates to adulthood: The PLINIUS study

Erythrocytes undergo a well-defined switch from fetal to postnatal circulation, which is mainly reflected by the stage-specific expression of hemoglobin chains. Perinatal alterations in thrombopoiesis are poorly understood. We assessed the ontogenesis of platelet phenotype and function from early prematurity to adulthood. We recruited 64 subjects comprising 7 extremely preterm (27-31 weeks gestational age), 25 moderately preterm (32-36 weeks), 10 term neonates, 8 infants (<2 years), 5 children (2-13 years), and 9 adults (>13 years). Blood was withdrawn at up to 3 different time points in neonates (t1: 0-2, t2: 3-7, and t3: 8-14 days after birth). We found that the expression levels of the major surface receptors for fibrinogen, collagen, vWF, fibronectin, and laminin were reduced but correlated with decreased platelet size, indicating a normal surface density. Although CD62P and CD63 surface exposure upon stimulation with TRAP-6, ADP, or U46619 was unaltered or only slightly reduced in neonates, GPIIb/IIIa inside-out and outside-in activation was blunted but showed a continuous increase until adulthood, correlating with the expression of the GPIIb/IIIa regulating tetraspanin CD151. Platelet subpopulation analysis using automated clustering revealed that neonates presented with a CD63+/PAC-1- pattern, followed by a continuous increase in CD63+/PAC-1+ platelets until adulthood. Our findings revealed that the number of platelet-monocyte and platelet-neutrophil aggregates, but not platelet-lymphocyte aggregates, is increased in neonates and that neonatal aggregate formation depends in part on CD62P activation. Our PLatelets In Neonatal Infants Study (PLINIUS) provides several lines of evidence that the platelet phenotype and function evolve continuously from neonates to adulthood.

Young apheresis platelet donors show significant and sustained growth over the last decade in the US, 2010-2019: A favorable sign of the resiliency of the platelet supply

BACKGROUND

Platelet demand continues to rise and US hospitals frequently face shortages. The peak median age of apheresis platelet donors (APD) is believed to have increased over the last decade, raising concerns that the APD base is not being adequately replenished with young donors.

STUDY DESIGN/METHODS

American Red Cross (ARC) apheresis platelet collections were evaluated from calendar years 2010 through 2019. APD, products per procedure/split rate (PPP) and donation frequencies were stratified into age groups.

RESULTS/FINDINGS

The number of unique APD from calendar year 2010 through 2019 in the ARC donor pool increased from 87,573 to 115,372 donors, representing a 31.7% overall growth. Donors in the 16-40 year-old (y) age group increased by 78.8% overall, with the largest absolute increases seen in the 26-30 y (4852 donors, 99.9% growth), followed by the 31-35 y (3991, 94.1%) group. Donors aged 56+ increased by 50.4% overall, with the largest increase seen in the 66-70 y (5988 donors, 108.1% growth) group. Middle-aged donors, aged 41-55 y, demonstrated a decrease of 16.5%. Over the last decade, the youngest age groups (16-40 y) comprised 61.3% of first-time donors (FTD). Annual donation frequency increased with increasing age and PPP. The highest donation frequencies were seen in the oldest age groups.

CONCLUSION

Although the peak median age of APD increased over the study period, relative contribution of the 16-40 y APD base also increased. Older donors exhibited the highest donation frequencies and thus contributed the largest volume of apheresis platelet units. Platelet donor activity declined in the middle age (41-55 y) group.

Baseline platelet serotonin in a multi-site treatment study of depression in veterans administration patients: Distribution and effects of demographic variables and serotonin reuptake inhibitors

BACKGROUND

The objectives of the study were: (1) to examine the overall distribution of baseline platelet serotonin (5-hydroxytryptamine, 5-HT) values in patients seeking treatment for depression and to define subgroups based on the apparent presence or absence of drug exposure; (2) to assess the bioeffect of 5-HT reuptake inhibitors (SRIs) at the platelet 5-HT transporter; and (3) to examine the relationships of demographic variables including population (ancestry), sex, age, and season of sampling to platelet 5-HT concentration.

METHODS

Platelet 5-HT levels were measured in a cross-sectional study of 1433 Veterans Administration (VA) patients participating in a pragmatic multi-site pharmacogenomic treatment study of depression. Patients were characterized medically and demographically using VA health records and self-report.

RESULTS

A clearly bimodal distribution was observed for platelet 5-HT levels with the lower mode associated with patients exposed to SRIs at baseline. Median transporter blockade bioeffects were similar across the various selective 5-HT reuptake inhibitors (SSRIs) and 5-HT/norepinephrine reuptake inhibitors (SNRIs). In a subset of patients apparently not exposed to an SRI, significant effects of population and sex were observed with group mean platelet 5-HT levels being 25 % greater (p < 0.001) in African-American (AA) individuals compared to European-Americans (EAs). The female group mean was 14 % (p < 0.001) greater than male group mean. An effect of age was observed (r = -0.11, p < 0.001) and no effect of season or month of sampling was seen.

CONCLUSIONS

Further research is warranted to understand the bases and clinical implications of the population and sex differences. The apparent similarity in bioeffect at the 5-HT transporter across SSRIs and when comparing SSRIs and SNRIs informs discussions about initiating, dose adjustment and switching of 5-HT reuptake inhibitors.

Progressive changes in platelet counts and Fib-4 scores precede the diagnosis of advanced fibrosis in NASH patients

BACKGROUND

Cirrhosis and its complications develop in a subgroup of patients with non-alcoholic fatty liver disease (NASH). Early detection of liver fibrosis represents an important goal of clinical care.

AIM

To test the hypothesis that the development of cirrhosis in nonalcoholic fatty liver disease patients is preceded by the long-term trends of platelet counts and Fib-4 scores.

METHODS

We identified all patients in our healthcare system who had undergone fibrosis staging by liver biopsy or magnetic resonance elastography (MRE) for non-alcoholic fatty liver disease during the past decade (n = 310). Platelet counts, serum glutamic-pyruvic transaminase and serum glutamic oxalacetic transaminase values preceding the staging tests were extracted from the electronic medical record system, and Fib-4 scores were calculated. Potential predictors of advanced fibrosis were evaluated using multivariate regression analysis.

RESULTS

Significant decreases in platelet counts and increases in Fib-4 scores were observed in all fibrosis stages, particularly in patients with cirrhosis. In the liver biopsy group, the presence of cirrhosis was best predicted by the combination of the Fib-4 score at the time closest to staging (P < 0.0001), the presence of diabetes (P = 0.0001), and the correlation coefficient of the preceding time-dependent drop in platelet count (P = 0.044). In the MRE group, Fib4 score (P = 0.0025) and platelet drop (P = 0.0373) were significant predictors. In comparison, the time-dependent rise of the Fib-4 score did not contribute in a statistically significant way.

CONCLUSION

Time-dependent changes in platelet counts and Fib-4 scores contribute to the prediction of cirrhosis in NASH patients with biopsy- or MRE-staged fibrosis. Their incorporation into predictive algorithms may assist in the earlier identification of high-risk patients.

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.

Risk Factors of Thrombocytopenia After Cardiac Surgery with Cardiopulmonary Bypass

INTRODUCTION

Postoperative thrombocytopenia is common in cardiac surgery with cardiopulmonary bypass, and its risk factors are unclear.

METHODS

This retrospective study enrolled 3,175 adult patients undergoing valve surgeries with cardiopulmonary bypass from January 1, 2017 to December 30, 2018 in our institute. Postoperative thrombocytopenia was defined as the first postoperative platelet count below the 10th quantile in all the enrolled patients. Outcomes between patients with and without postoperative thrombocytopenia were compared. The primary outcome was in-hospital mortality. Risk factors of postoperative thrombocytopenia were assessed by logistic regression analysis.

RESULTS

The 10th quantile of all enrolled patients (75×109/L) was defined as the threshold for postoperative thrombocytopenia. In-hospital mortality was comparable between thrombocytopenia and non-thrombocytopenia groups (0.9% vs. 0.6%, P=0.434). Patients in the thrombocytopenia group had higher rate of postoperative blood transfusion (5.9% vs. 3.2%, P=0.014), more chest drainage volume (735 [550-1080] vs. 560 [430-730] ml, P<0.001), and higher incidence of acute kidney injury (12.3% vs. 4.2%, P<0.001). Age > 60 years (odds ratio [OR] 2.25, 95% confidence interval [CI] 1.345-3.765, P=0.002], preoperative thrombocytopenia (OR 18.671, 95% CI 13.649-25.542, P<0.001), and cardiopulmonary bypass time (OR 1.088, 95% CI 1.059-1.117, P<0.001) were positively independently associated with postoperative thrombocytopenia. Body surface area (BSA) (OR 0.247, 95% CI 0.114-0.538, P<0.001) and isolated mitral valve surgery (OR 0.475, 95% CI 0.294-0.77) were negatively independently associated with postoperative thrombocytopenia.

CONCLUSION

Positive predictors for thrombocytopenia after valve surgery included age > 60 years, small BSA, preoperative thrombocytopenia, and cardiopulmonary bypass time. BSA and isolated mitral valve surgery were negative predictors.

Higher platelet count, even within normal range, is associated with increased arterial stiffness in young and middle-aged adults

Background: Platelet counts and mean platelet volume (MPV) are related to cardiovascular disease, but a thorough investigation into the connection between increased arterial stiffness, MPV, and platelet counts is lacking. This study aimed to explore the association of platelet count and MPV with arterial stiffness in young and middle-aged adults.

Methods: A total of 2464 participants who underwent health checkups at National Cheng Kung University Hospital, Taiwan from November 2018 to December 2019 were included. We excluded participants aged <18 or >50 years; who are pregnant; on medication for dyslipidemia; with abnormal platelet count, incomplete data, and past history of hematologic disorders. We examined the association of platelet counts and MPV values with brachial-ankle pulse wave velocity (baPWV) levels and increased arterial stiffness.

Results: Platelet count was significantly higher in participants with increased arterial stiffness than in those without. The multiple linear regression model revealed that platelet counts were positively associated with baPWV levels (β = 1.88, 95% confidence interval (CI): 0.96 to 2.80). In the binary logistic regression analysis, subjects in the higher platelet counts quartiles had a higher risk of developing increased arterial stiffness (Q2 vs. Q1: odds ratio (OR): 1.54, 95% CI: 1.05 to 2.27; Q3 vs. Q1: OR: 1.57, 95% CI: 1.06 to 2.33; and Q4 vs. Q1: OR: 2.23, 95% CI: 1.50 to 3.30). In contrast, MPV levels were not associated with arterial stiffness.

Conclusions: Platelet count in midlife was positively associated with baPWV levels. Participants in higher platelet quartiles were at risk for increased arterial stiffness.

Analysis of time-dependent changes in the FIB4 index in patients with obesity receiving weight reduction therapy

Weight reduction therapy represents a fundamental strategy to prevent nonalcoholic fatty liver disease (NAFLD) in patients with obesity, which may result in liver fibrosis. Histological findings previously demonstrated that weight reduction therapy attenuated NAFLD. The FIB4 index is widely used to assess the status of NAFLD. The present study investigated whether the FIB4 index improved during weight reduction therapy. We used cohort data of the Japan Obesity and Metabolic syndrome Study and examined the correlation between body weight (BW) loss (BW loss) and changes in the FIB4 index (ΔFIB4 index) in patients who successfully reduced their BW by more than 5% from baseline BW after 3, 6, and 12 months (M) of weight reduction therapy. A negative correlation (r = −0.342, p = 0.029) was observed between BW loss and FIB4 index after 3 M, but not after 6 M, whereas a positive correlation (r = 0.298, p = 0.03) was noted after 12 M. These results revealed changes in the correlation between ΔBW loss and ΔFIB4 index during the therapy, mainly due to time-dependent changes in components of the FIB4 index formula. Thus, we concluded that the FIB4 index is useful and reliable to assess liver fibrosis until 3 M during weight reduction therapy. However, after 3 M, we should recognize that the FIB4 index may not reflect liver status. Therefore, it is important to consider this characteristic of the FIB4 index as a limitation when assessing liver fibrosis in obese patients receiving weight reduction therapy.

Long-term follow-up and liver outcomes in children with cystic fibrosis and nodular liver on ultrasound in a multi-center study

BACKGROUND

Nodular liver (NOD) in cystic fibrosis (CF) suggests advanced CF liver disease (aCFLD); little is known about progression of liver disease (LD) after detection of sonographic NOD.

METHODS

Clinical, laboratory, and ultrasound (US) data from Prediction by Ultrasound of the Risk of Hepatic Cirrhosis in CFLD Study participants with NOD at screening or follow-up were compared with normal (NL). Linear mixed effects models were used for risk factors for LD progression and Kaplan-Meier estimator for time-to-event.

RESULTS

54 children with NOD (22 screening, 32 follow-up) and 112 NL were evaluated. Baseline (BL) and trajectory of forced expiratory volume, forced vital capacity, height/BMI z-scores were similar in NOD vs NL. Platelets were lower in NOD at BL (250 vs 331×10³/microL; p < 0.001) and decreased by 8600/year vs 2500 in NL. Mean AST to Platelet Ratio Index (1.1 vs 0.4; p < 0.001), Fibrosis-4 Index (0.4 vs 0.2, p < 0.001), and spleen size z-score (SSZ) [1.5 vs 0.02; p < 0.001] were higher in NOD at BL; SSZ increased by 0.5 unit/year in NOD vs 0.1 unit/year in NL. Median liver stiffness (LSM) by transient elastography was higher in NOD (8.2 kPa, IQR 6-11.8) vs NL (5.3, 4.2-7, p < 0.0001). Over 6.3 years follow-up (1.3-10.3), 6 NOD had esophageal varices (cumulative incidence in 10 years: 20%; 95% CI: 0.0%, 40.0%), 2 had variceal bleeding, and 2 underwent liver transplantation; none had ascites or hepatic encephalopathy. No NL experienced liver-related events.

CONCLUSIONS

NOD developed clinically evident portal hypertension faster than NL without worse growth or lung disease.

Comparison of thrombocytopenia between patients with non-alcoholic fatty liver disease and those with hepatitis C virus-related chronic liver disease

AIM

Thrombocytopenia is widely recognized as a simple surrogate marker of liver fibrosis in non-alcoholic fatty liver disease (NAFLD). Thrombocytopenia of NAFLD has not been compared with that of hepatitis C virus-related chronic liver disease (CLD-C). Here, we examined whether there is any difference in the platelet counts between patients with NAFLD and CLD-C and investigated the underlying mechanisms.

METHODS

A total of 760 biopsy-confirmed NAFLD and 1171 CLD-C patients were enrolled. After stratification according to the liver fibrosis stage, platelet counts between NAFLD and CLD-C patients were compared. The platelet count, spleen size, serum albumin level, serum thrombopoietin level, and immature platelet fraction (IPF) value were also compared after covariate adjustment using propensity score (PS) matching.

RESULTS

The median platelet counts (×10⁴ /μL) of NAFLD and CLD-C patients were 20.2 and 18.7 (p = 2.4 × 10^-5 ) in F1; 20.0 and 14.5 (p = 2.1 × 10^-12 ) in F2; 16.9 and 12.3 (p = 8.1 × 10^-10 ) in F3; and 11.1 and 8.1 (p = 0.02) in F4, respectively. In the F3 group, NAFLD patients had a significantly higher platelet count and significantly smaller spleen volume than CLD-C patients. Although the serum thrombopoietin levels were comparable between NAFLD and CLD-C patients, the IPF value of NAFLD patients was significantly higher than that of CLD-C patients.

CONCLUSIONS

NAFLD patients had a significantly higher platelet count than CLD-C patients following stratification according to the liver fibrosis stage. The milder hypersplenism and higher platelet production in NAFLD than CLD-C may have contributed to this difference.

Longitudinal changes in personalized platelet count metrics are good indicators of initial 3-year outcome in colorectal cancer

BACKGROUND

Platelet count or complete blood count (CBC)-based ratios including lymphocyte-to-monocyte (LMR), neutrophil-to-lymphocyte (NLR), hemoglobin-to-platelet (HPR), red blood cell count distribution width-to-platelet (RPR), and platelet-to-lymphocyte (PLR) ratio are good predictors of colorectal cancer (CRC) survival. Their change in time is not well documented, however.

AIM

To investigate the effect of longitudinal CBC ratio changes on CRC survival and their possible associations with clinicopathological properties, comorbidities, and anamnestic data.

METHODS

A retrospective longitudinal observational study was conducted with the inclusion of 835 CRC patients, who attended at Semmelweis University, Budapest. CBC ratios and two additional newly defined personalized platelet count metrics (pPLTD and pPLTS, the platelet counts relative to the measurement at the time of CRC diagnosis and to the one 4-6 wk after tumor removal surgery, respectively) were recorded.

RESULTS

The 835 CRC patients had a total of 4608 measurements (5.52 visits/patient, in average). Longitudinal survival models revealed that the increases/decreases in LMR [hazard ratio (HR): 0.4989, P < 0.0001], NLR (HR: 1.0819, P < 0.0001), HPR (HR: 0.0533, P = 0.0038), pPLTD (HR: 4.9229, P < 0.0001), and pPLTS (HR: 4.7568, P < 0.0001) values were poor prognostic signs of disease-specific survival. The same was obtained for all-cause mortality. Most abnormal changes occurred within the first 3 years after the diagnosis of CRC. RPR and PLR had an only marginal effect on disease-specific (P = 0.0675) and all-cause mortality (Bayesian 95% credible interval: 0.90-186.05), respectively.

CONCLUSION

LMR, NLR, and HPR are good metrics to follow the prognosis of the disease. pPLTD and pPLTS perform just as well as the former, while the use of RPR and PLR with the course of the disease is not recommended. Early detection of the abnormal changes in pPLTD, pPLTS, LMR, NLR, or HPR may alert the practicing oncologist for further therapy decisions in a timely manner.

Higher platelet counts correlate to tumour progression and can be induced by intratumoural stroma in non-metastatic breast carcinomas

BACKGROUND

Platelets support tumour progression. However, their prognostic significance and relation to circulating tumour cells (CTCs) in operable breast cancer (BrCa) are still scarcely known and, thus, merit further investigation.

METHODS

Preoperative platelet counts (PCs) were compared with clinical data, CTCs, 65 serum cytokines and 770 immune-related transcripts obtained using the NanoString technology.

RESULTS

High normal PC (hPC; defined by the 75th centile cut-off) correlated with an increased number of lymph node metastases and mesenchymal CTCs in the 70 operable BrCa patients. Patients with hPC and CTC presence revealed the shortest overall survival compared to those with no CTC/any PC or even CTC/normal PC. Adverse prognostic impact of hPC was observed only in the luminal subtype, when 247 BrCa patients were analysed. hPC correlated with high content of intratumoural stroma, specifically its phenotype related to CD8+ T and resting mast cells, and an increased concentration of cytokines related to platelet activation or even production in bone marrow (i.e. APRIL, ENA78/CXCL5, HGF, IL16, IL17a, MDC/CCL22, MCP3, MMP1 and SCF).

CONCLUSIONS

Preoperative platelets evaluated alone and in combination with CTCs have prognostic potential in non-metastatic BrCa and define patients at the highest risk of disease progression, putatively benefiting from anti-platelet therapy.

Influence of Thrombocytopenia on the Outcome of Mechanical Thrombectomy in Patients with Acute Ischemic Stroke

OBJECTIVES

Mechanical thrombectomy (MT) has become leading treatment option for acute ischemic stroke (AIS) due to large vessels occlusion (LVO). Platelet counts may affect outcome in patients with AIS or transient ischemic attack. The aim of our study was to determine the influence of thrombocytopenia on the safety and efficacy of MT in patients with AIS due to anterior circulation LVO.

MATERIALS AND METHODS

This study included 127 consecutive adult patients with AIS due to anterior circulation LVO who underwent MT. The patients were divided into 2 groups based on initial platelet count: with thrombocytopenia (<150 × 10⁹/L) and without thrombocytopenia (≥150 × 10⁹/L). Primary safety outcome was symptomatic intracerebral haemorrhage (SICH), while secondary safety outcome was stroke-related mortality. Efficacy outcome was functional independence, defined as modified Rankin Scale (mRS) score 0-2. Follow- up time was 90 days.

RESULTS

Initial thrombocytopenia (<150 × 10⁹/L) was detected in 19 (15%) patients. Multivariable analysis showed that initial thrombocytopenia did not increase the risk of SICH and did not affect the short-term functional outcome (p = 0.587). However, initial thrombocytopenia increased the risk for stroke-related mortality (aOR 3.639, 95% CI 1.079-12.641, p = 0.037). The main cause of mortality in the group with thrombocytopenia was malignant cerebral infarction (44.4%).

CONCLUSIONS

Thrombocytopenia does not affect the efficacy and the risk of SICH in patients with AIS caused by anterior circulation LVO treated with MT. However, the risk of mortality is higher in patients with thrombocytopenia, mainly due to malignant cerebral infarction.

Can platelet activation result in increased plasma Aβ levels and contribute to the pathogenesis of Alzheimer's disease?

One of the central lesions in the brain of subjects with Alzheimer's disease (AD) is represented by aggregates of β-amyloid (Aβ), a peptide of 40-42 amino acids derived from the amyloid precursor protein (APP). The reasons why Aβ accumulates in the brain of individuals with sporadic forms of AD are unknown. Platelets are the primary source of circulating APP and, upon activation, can secrete significant amounts of Aβ into the blood which can be actively transported to the brain across the blood-brain barrier and promote amyloid deposition. Increased platelet activity can stimulate platelet adhesion to endothelial cells, trigger the recruitment of leukocytes into the vascular wall and cause perivascular inflammation, which can spread inflammation in the brain. Neuroinflammation is fueled by activated microglial cells and reactive astrocytes that release neurotoxic cytokines and chemokines. Platelet activation is also associated with the progression of carotid artery disease resulting in an increased risk of cerebral hypoperfusion which may also contribute to the AD neurodegenerative process. Platelet activation may thus be a pathophysiological mechanism of AD and for the strong link between AD and cerebrovascular diseases. Interfering with platelet activation may represent a promising potential adjunct therapeutic approach for AD.

Prognostic significance of pretreatment thrombocytosis in endometrial cancer: an Israeli Gynecologic Oncology Group study

OBJECTIVE

Endometrial cancer prognosis is related to stage, histology, myometrial invasion, and lymphovascular space invasion. Several studies have examined the association between pretreatment thrombocytosis and patient outcomes with contrasting results regarding prognosis. Our aim was to evaluate the association of pretreatment platelet count with outcomes in endometrial cancer patients.

METHODS

This is an Israeli Gynecologic Oncology Group multicenter retrospective cohort study of consecutive patients with endometrial cancer, who underwent surgery between January 2002 and December 2014. Patients were grouped as low risk (endometrioid G1-G2 and villoglandular) and high risk (endometrioid G3, uterine serous papillary carcinoma, clear cell carcinoma, and carcinosarcoma). Those with stage I disease were compared with stages II-IV. Disease stages were reviewed and updated to reflect International Federation of Gynecology and Obstetrics (FIGO) 2009 staging. All patients underwent pelvic washings for cytology and total abdominal or laparoscopic hysterectomy with bilateral salpingo-oophorectomy. Pelvic lymph node assessment was performed in patients with tumors of moderate-high risk histology or deep myometrial invasion. Para-aortic sampling was performed at the surgeon's discretion. Patients were categorized by pretreatment platelet count into two groups: ≤400×109/L and >400×109/L (defined as thrombocytosis). Clinical and pathological features were compared using Student t-test, χ2 or Fisher's exact test. Survival measures were plotted with the Kaplan-Meier method and compared using the log-rank test. A Cox proportional hazards model was used for multivariable comparison of associations.

RESULTS

Of the 1482 patients included, most had stage I disease (961; 74.8%) and most had endometrioid histology (927; 64.1%). A total of 1392 patients (94%) had pretreatment platelet counts ≤400×109/L and 90 (6%) had pretreatment thrombocytosis. Patients with thrombocytosis had a significantly higher rate of high-grade malignancy, advanced stage, lymphovascular space invasion, low uterine segment involvement, and lymph node metastases. They also had shorter 5 year disease-free survival (65% vs 80%, p=0.003), disease-specific survival (63% vs 83%, p<0.05) and overall survival (59% vs 77%, p<0.05). On multivariate analysis, an elevated pretreatment thrombocyte count remained a significant independent predictor for disease-specific survival and overall survival.

CONCLUSIONS

Pretreatment thrombocytosis is an independent prognostic factor for decreased disease-specific survival and overall survival among patients with endometrial cancer, and can serve as a predictor of poor outcome.

Hemogram-based decision tree for predicting the metabolic syndrome and cardiovascular diseases in the elderly

BACKGROUND

This study aimed to build a hemogram-based decision tree to evaluate the association between current probability of metabolic syndrome (MetS) and prediction of future hypertension, type 2 diabetes and cardiovascular diseases (CVD) risk.

METHODS

A total of 40 395 elder participants (≥60 years) were enrolled in a standard health examination program in Taiwan from January 1999 to December 2014. A decision tree classification of the presence or absence of MetS at baseline, using age, sex and hemogram (white blood cell, hemoglobin and platelet) as independent variables, was conducted for the randomly assigned training (70%) and validation (30%) groups. Participants without MetS at baseline (n = 25 643) were followed up to observe whether they developed MetS, hypertension, type 2 diabetes or CVD in the future.

RESULTS

Modest accuracy of the decision tree in the training and validation groups with area under the curves of 0.653 and 0.652, respectively, indicated an acceptable generalizability of results. The predicted probability of baseline MetS was obtained from decision tree analysis. Participants without MetS at baseline were categorized into three equally sized groups according to the predicted probability. Participants in the third tertile had significantly higher risks of future MetS (hazard ratio 1.40, 95% confidence interval 1.25-1.58); type 2 diabetes (1.46, 1.17-1.83); hypertension (1.14, 1.01-1.28); and CVD (1.21, 1.01-1.44), compared with those in the first tertile.

CONCLUSIONS

Execution of hemogram-based decision tree analysis can assist in early identification and prompt management of elderly patients at a high risk of future hypertension, type 2 diabetes and CVD.

Vitamin D and Platelets: A Menacing Duo in COVID-19 and Potential Relation to Bone Remodeling

Global data correlate severe vitamin D deficiency with COVID-19-associated coagulopathy, further suggesting the presence of a hypercoagulable state in severe COVID-19 patients, which could promote thrombosis in the lungs and in other organs. The feedback loop between COVID-19-associated coagulopathy and vitamin D also involves platelets (PLTs), since vitamin D deficiency stimulates PLT activation and aggregation and increases fibrinolysis and thrombosis. Vitamin D and PLTs share and play specific roles not only in coagulation and thrombosis but also during inflammation, endothelial dysfunction, and immune response. Additionally, another ‘fil rouge’ between vitamin D and PLTs is represented by their role in mineral metabolism and bone health, since vitamin D deficiency, low PLT count, and altered PLT-related parameters are linked to abnormal bone remodeling in certain pathological conditions, such as osteoporosis (OP). Hence, it is possible to speculate that severe COVID-19 patients are characterized by the presence of several predisposing factors to bone fragility and OP that may be monitored to avoid potential complications. Here, we hypothesize different pervasive actions of vitamin D and PLT association in COVID-19, also allowing for potential preliminary information on bone health status during COVID-19 infection.

Review of potentials and limitations of indirect approaches for estimating reference limits/intervals of quantitative procedures in laboratory medicine

Reference intervals (RIs) can be determined by direct and indirect procedures. Both approaches identify a reference population from which the RIs are defined. The crucial difference between direct and indirect methods is that direct methods select particular individuals after individual anamnesis and medical examination have confirmed the absence of pathological conditions. These individuals form a reference subpopulation. Indirect methods select a reference subpopulation in which the individuals are not identified. They isolate a reference population from a mixed population of patients with pathological and non-pathological conditions by statistical reasoning.

At present, the direct procedure internationally recommended is the “gold standard”. It has, however, the disadvantage of high expenses which cannot easily be afforded by most medical laboratories. Therefore, laboratories adopt RIs established by direct methods from external sources requiring a high responsibility for transference problems which are usually neglected by most laboratories. These difficulties can be overcome by indirect procedures which can easily be performed by most laboratories without causing economic problems.

The present review focuses on indirect approaches. Various procedures are presented with their benefits and limitations. Preliminary simulation studies indicate that more recently developed concepts are superior to older approaches.

C-reactive protein/albumin ratio predicts survival after curative surgery in elderly patients with colorectal cancer

Inflammation-based markers, including the C-reactive protein/albumin ratio (CAR), lymphocyte/monocyte ratio (LMR), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), Onodera's prognostic nutritional index (PNI), and Glasgow Prognostic Score (GPS), have been demonstrated to serve as prognostic indicators in various malignancies. This study aimed to evaluate their potential predictive value for colorectal cancer (CRC) in the elderly. We retrospectively evaluated 163 patients with CRC, aged 80 years and older, who had undergone curative surgery. The receiver operating characteristic curve analyses and the corresponding areas under the curve (AUCs) were used to determine and compare the discriminatory ability of the inflammation-based markers. Besides, the associations of inflammatory markers and clinical characteristics with overall survival (OS), relapse-free survival (RFS), and cancer-specific survival (CSS) were analyzed. The CAR had a significantly larger AUC than the GPS, PLR, NLR, and LMR (p = 0.006, 0.012, 0.018, and 0.002, respectively), except for the PNI (p = 0.052). The optimal cut-off value was 0.106 for the CAR and 44.894 for the PNI. Moreover, a CAR ≥ 0.106 turned out to be significantly associated with worse 5-year OS, RFS, and CSS compared with a CAR < 0.106. The multivariate analysis indicated that the CAR ≥ 0.106 was an independent prognostic factor for poor OS (HR = 3.596, p = 0.0006), RFS (HR = 2.945, p = 0.003), and CSS (HR = 4.411, p = 0.02). CAR is a useful and promising prognostic marker in elderly patients undergoing curative surgery for CRC.

EDTA-dependent pseudothrombocytopenia in patients with hepatosplenic schistosomiasis mansoni: a clinical management alert

BACKGROUND

Hepatosplenic schistosomiasis mansoni (HS) is associated with thrombocytopenia. Accurate platelet counts are required for identification and management of HS patients. EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) is an in vitro phenomenon of anticoagulant-activated platelet agglutination resulting in low platelet counts by automated methods. The prevalence of EDTA-PCTP in schistosomiasis is unknown and only one case has been described. Our aims were to determine the prevalence of EDTA-PTCP in HS and evaluate alternative methods to overcome this analytical error.

METHODS

Blood samples from 56 HS patients and 56 healthy volunteers were collected, and platelet counts were obtained using standard microscopy and automated (electric impedance) methods. Automated platelet counts and the presence of platelet clumps in blood smears were evaluated in samples collected in EDTA or sodium citrate tubes 20 and 180 min after blood collection.

RESULTS

EDTA-PTCP was more frequent in HS patients than healthy volunteers (8.92% vs 0.00%, p<0.0285). Platelet clumps and PTCP were also observed in samples collected in sodium citrate tubes, refuting its use as an alternative method.

CONCLUSIONS

Automated platelet counts in blood samples from HS patients should be performed right after blood collection in EDTA tubes and verified by manual counts in blood smears.

Indirect estimation of reference intervals using first or last results and results from patients without repeated measurements

Objectives

Indirect methods for the estimation of Reference Limits (RLs) use large data pools stored in modern laboratory information’s systems. To avoid correlation between observations repeated results from each patient should be excluded. Some data pools obtained are anonymized, and thereafter the data cannot be re-identified. The effect of the procedure of data selection on the estimations is not investigated yet.

Methods

We considered four parameters. Data sets were enclosed from two sources: a university hospital and a laboratory primarily reflecting a patient population from medical practitioners. Four algorithms were used for data selection, which generate first, last, all and non-repeated values. RLs were estimated through these data sets and compared.

Results

This study showed the broader reference range estimated by indirect methods if using the whole data set compared to first/last values or non-repeated values.

Conclusions

The use of all data without a filtering step results in a significant bias whereas the choice of first or last values has nearly no impact. The exclusion of repeated measurements results in narrower RLs. This influence confine the use of anonymous data sets where filtering is impossible for the estimation of RLs by indirect methods.

Antithrombotic strategies in elderly patients with acute coronary syndrome

Elderly patients represent a growing proportion of the acute coronary syndrome population in Western countries. However, their frequent atypical symptoms at presentation often lead to delays in management and to misdiagnosis. Furthermore, their prognosis is poorer than that of younger patients because of physiological changes in platelet function, haemostasis and fibrinolysis, but also a higher proportion of comorbidities and frailty, both of which increase the risk of recurrent thrombotic and bleeding events. This complex situation, with ischaemic and haemorrhagic risk factors often being intertwined, may lead to confusion about the required treatment strategy, sometimes resulting in inadequate management or even to therapeutic nihilism. It is therefore critical to provide a comprehensive overview of our understanding of the pathophysiological processes underlying acute coronary syndrome in elderly patients, and to summarise the results from the latest clinical trials to help decision making for these high-risk patients.

The Cutaneous Wound Innate Immunological Microenvironment

The skin represents the first line of defense and innate immune protection against pathogens. Skin normally provides a physical barrier to prevent infection by pathogens; however, wounds, microinjuries, and minor barrier impediments can present open avenues for invasion through the skin. Accordingly, wound repair and protection from invading pathogens are essential processes in successful skin barrier regeneration. To repair and protect wounds, skin promotes the development of a specific and complex immunological microenvironment within and surrounding the disrupted tissue. This immune microenvironment includes both innate and adaptive processes, including immune cell recruitment to the wound and secretion of extracellular factors that can act directly to promote wound closure and wound antimicrobial defense. Recent work has shown that this immune microenvironment also varies according to the specific context of the wound: the microbiome, neuroimmune signaling, environmental effects, and age play roles in altering the innate immune response to wounding. This review will focus on the role of these factors in shaping the cutaneous microenvironment and how this ultimately impacts the immune response to wounding.

Defective platelet function in Niemann-Pick disease type C1

Niemann-Pick disease type C (NPC) is a neurodegenerative lysosomal storage disorder caused by mutations in either NPC1 (95% of cases) or NPC2. Reduced late endosome/lysosome calcium (Ca2+) levels and the accumulation of unesterified cholesterol and sphingolipids within the late endocytic system characterize this disease. We previously reported impaired lysosome-related organelle (LRO) function in Npc1 -/- Natural Killer cells; however, the potential contribution of impaired acid compartment Ca2+ flux and LRO function in other cell types has not been determined. Here, we investigated LRO function in NPC1 disease platelets. We found elevated numbers of circulating platelets, impaired platelet aggregation and prolonged bleeding times in a murine model of NPC1 disease. Electron microscopy revealed abnormal ultrastructure in murine platelets, consistent with that seen in a U18666A (pharmacological inhibitor of NPC1) treated megakaryocyte cell line (MEG-01) exhibiting lipid storage and acidic compartment Ca2+ flux defects. Furthermore, platelets from NPC1 patients across different ages were found to cluster at the lower end of the normal range when platelet numbers were measured and had platelet volumes that were clustered at the top of the normal range. Taken together, these findings highlight the role of acid compartment Ca2+ flux in the function of platelet LROs.

Dynamics of cytokines, immune cell counts and disease severity in patients with community-acquired pneumonia - Unravelling potential causal relationships

BACKGROUND

Community acquired pneumonia (CAP) is a severe and often rapidly deteriorating disease. To better understand its dynamics and potential causal relationships, we analyzed time series data of cytokines, blood and clinical parameters in hospitalized CAP patients.

METHODS

Time series data of 10 circulating cytokines, blood counts and clinical parameters were related to baseline characteristics of 403 CAP patients using univariate mixed models. Bivariate mixed models were applied to analyze correlations between the time series. To identify potential causal relationships, we inferred cross-lagged relationships between pairs of parameters using latent curve models with structured residuals.

RESULTS

IL-6 levels decreased faster over time in younger patients (P_adj = 0.06). IL-8, VCAM-1, and IL-6 correlated strongly with disease severity as assessed by the sequential organ failure assessment (SOFA) score (r = 0.49, 0.48, 0.46, respectively; all P_adj < 0.001). IL-6 and bilirubin correlated with respect to their mean levels and slopes over time (r = 0.36 and r = 0.46, respectively; P_adj < 0.001). A number of potential causal relationships were identified, e.g., a negative effect of ICAM-1 on MCP-1, or a positive effect of the level of creatinine on the subsequent VCAM-1 concentration (P < 0.001).

CONCLUSIONS

These results suggest that IL-6 trajectories of CAP patients are associated with age and run parallel to bilirubin levels. The time series analysis also unraveled directed, potentially causal relationships between cytokines, blood parameters and clinical outcomes. This will facilitate the development of mechanistic models of CAP, and with it, improvements in treatment or surveillance strategies for this disease.

TRIAL REGISTRATION

clinicaltrials.gov NCT02782013, May 25, 2016, retrospectively registered.

Cancer incidence following a high-normal platelet count: cohort study using electronic healthcare records from English primary care

Background

A raised platelet count (thrombocytosis) measuring >400 × 10⁹/l is associated with high cancer incidence. It is uncertain whether platelet counts at the upper end of the normal range (high-normal: 326–400 × 10⁹/l) are also associated with cancer.

Aim

To investigate cancer incidence following a normal platelet count in primary care.

Design and setting

A prospective cohort study was undertaken using data from the Clinical Practice Research Datalink and National Cancer Registration and Analysis Service, dating from 1 May 2005 to 30 April 2014.

Method

One-year cancer incidence was estimated for 295 312 patients with normal platelet counts (150–400 × 10⁹/l). Patients with platelet counts >325 × 10⁹/l were oversampled to maximise precision of estimates of cancer incidence. All patients were aged ≥40 years with no prior cancer diagnoses. The effects of age, sex, and smoking were explored. Non-melanoma skin cancers were omitted from exclusions and incidence.

Results

One-year cancer incidence increased greatly with age, male sex, and higher platelet count. Males aged ≥60 years with a high-normal count had an incidence of 4.2% (95% confidence interval [CI] = 4.0 to 4.4). The highest incidence of 6.7% (95% CI = 5.3 to 8.4) was found in males aged ≥80 years, who had platelets in the range of 376–400 × 10⁹/l; this was 3.1 percentage points higher than the incidence for patients in the same age group with lower-normal counts of 150–325 × 10⁹/l. Risks for all female subgroups were <3%. Patients with high-normal platelet counts were most at risk of lung and colorectal cancers and, in general, had advanced-stage cancer at diagnosis.

Conclusion

Platelet counts at the high-normal range in males aged ≥60 years may be indicative of an underlying malignancy, and referral for further investigation should be considered.

A 25-y longitudinal dolphin cohort supports that long-lived individuals in same environment exhibit variation in aging rates

Aging is a degradative process that varies among individuals. Due to limitations in defining and differentiating aging rates in human populations, understanding why some people appear to age slower than others has proven difficult. We analyzed 44 blood-based indices of health as candidate aging rate biomarkers collected over a 25-y period on a relevant, long-lived population of dolphins. Evidence of subsets of dolphins exhibiting slow and accelerated aging rates were detected, despite sharing the same environment, diet, and health care. Furthermore, some dolphin subsets were more likely to develop clinically relevant conditions, including anemia and immunosenescence. Our results support the notion that aging rates in long-lived mammals may be defined and provide insight into novel interventions to delay aging.

While it is believed that humans age at different rates, a lack of robust longitudinal human studies using consensus biomarkers meant to capture aging rates has hindered an understanding of the degree to which individuals vary in their rates of aging. Because bottlenose dolphins are long-lived mammals that develop comorbidities of aging similar to humans, we analyzed data from a well-controlled, 25-y longitudinal cohort of 144 US Navy dolphins housed in the same oceanic environment. Our analysis focused on 44 clinically relevant hematologic and clinical chemistry measures recorded during routine blood draws throughout the dolphins’ lifetimes. Using stepwise regression and general linear models that accommodate correlations between measures obtained on individual dolphins, we demonstrate that, in a manner similar to humans, dolphins exhibit independent and linear age-related declines in four of these measures: hemoglobin, alkaline phosphatase, platelets, and lymphocytes. Using linear regressions and analyses of covariance with post hoc Tukey–Kramer tests to compare slopes (i.e., linear age-related rates) of our four aging rate biomarkers among 34 individual dolphins aging from 10 y to up to 40 y old, we could identify slow and accelerated agers and differentiate subgroups that were more or less likely to develop anemia and lymphopenia. This study successfully documents aging rate differences over the lifetime of long-lived individuals in a controlled environment. Our study suggests that nonenvironmental factors influencing aging rate biomarkers, including declining hemoglobin and anemia, may be targeted to delay the effects of aging in a compelling model of human biology.

Platelet functions and activities as potential hematologic parameters related to Coronavirus Disease 2019 (Covid-19)

Coronavirus disease 2019 (COVID-19) is a new infectious disease that currently lacks standardized and established laboratory markers to evaluate its severity. In COVID-19 patients, the number of platelets (PLTs) and dynamic changes of PLT-related parameters are currently a concern. The present paper discusses the potential link between PLT parameters and COVID-19. Several studies have identified a link between severe COVID-19 patients and specific coagulation index, in particular, high D-dimer level, prolonged prothrombin time, and low PLT count. These alterations reflect the hypercoagulable state present in severe COVID-19 patients, which could promote microthrombosis in the lungs, as well as in other organs. Further information and more advanced hematological parameters related to PLTs are needed to better estimate this link, also considering COVID-19 patients at different disease stages and stratified in different cohorts based on preexisting co-morbidity, age, and gender. Increasing the understanding of PLT functions in COVID-19 will undoubtedly improve our knowledge on disease pathogenesis, clinical management, and therapeutic options, but could also lead to the development of more precise therapeutic strategies for COVID-19 patients.