Recombinant human thrombopoietin in critically ill patients with sepsis-associated thrombocytopenia: A clinical study

Thrombocytopenia in Sepsis

Platelets, traditionally known for their role in hemostasis, have emerged as key players in immune response and inflammation. Sepsis, a life-threatening condition characterized by systemic inflammation, often presents with thrombocytopenia, which at times, can be significant. Platelets contribute to the inflammatory response by interacting with leukocytes, endothelial cells, and the innate immune system. However, excessive platelet activation and consumption can lead to thrombocytopenia and exacerbate the severity of sepsis. Understanding the multifaceted roles of platelets in sepsis is crucial for developing effective therapeutic strategies. Targeting platelet-mediated inflammatory responses and promoting platelet production may offer potential avenues for improving outcomes in septic patients with thrombocytopenia. Future research should focus on elucidating the mechanisms underlying platelet dysfunction in sepsis and exploring novel therapeutic approaches to optimize platelet function and mitigate inflammation. This review explores the intricate relationship between platelets, inflammation, and thrombosis in the context of sepsis.

Factors influencing sepsis associated thrombocytopenia (SAT): A multicenter retrospective cohort study

INTRODUCTION

Sepsis associated thrombocytopenia (SAT) is a common complication of sepsis. We designed this study to investigate factors influencing SAT.

METHODS

Patients with sepsis (2984 in Peking union medical college hospital [PUMCH] database, 13165 in eICU Collaborative Research [eICU] database, 11101 in Medical Information Mart for Intensive Care IV [MIMIC-IV] database) were enrolled. Variables included basic information, comorbidities, and organ functions. Multi-variable logistic regression models and artificial neural network model were applied to determine the factors related to SAT.

MAIN RESULTS

Age and body mass index (BMI) were inversely correlated with the incidence of SAT (p-value 0.175 and 0.049 [PUMCH], p-value 0.000 and 0.000 [eICU], p-value 0.000 and 0.000 [MIMIC-IV]). Hematologic malignancies and other malignancies were positively correlated with the incidence of SAT (p-value 0.000 and 0.000 [PUMCH], p-value 0.000 and 0.000 [eICU], p-value 0.000 and 0.020 [MIMIC-IV]) except other malignancies was inversely correlated with the incidence of SAT in PUMCH database. Norepinephrine (NE) equivalents, total bilirubin (TBIL) and creatinine were positively correlated with the incidence of SAT (p-value 0.000, 0.000 and 0.011 [PUMCH], p-value 0.028, 0.000 and 0.013 [eICU], p-value 0.028, 0.000 and 0.027 [MIMIC-IV]). PaO2 / FiO2 was inversely correlated with the incidence of SAT in PUMCH database (p-value 0.021 [PUMCH]), while it was positively correlated with the incidence of SAT (p-value 0.000 [MIMIC-IV]). PaO2 / FiO2 and SAT was not related (p-value 0.111 [eICU]). TBIL, hematologic malignancies, PaO2 / FiO2 and NE equivalents ranked in the top five significant variables in all three datasets.

CONCLUSIONS

Hematologic malignancies and other malignancies were positively correlated with the incidence of SAT. NE equivalents, TBIL and creatinine were positively correlated with the incidence of SAT. TBIL, hematologic malignancies, PaO2 / FiO2 and NE equivalents ranked in the top significant variables in factors influencing SAT.

Biliary sepsis complication with congenital hepatic fibrosis: an unexpected outcome

BACKGROUND

CHF (Congenital hepatic fibrosis) is a rare hereditary disease characterized by periportal fibrosis and ductal plate malformation. Little is known about the clinical presentations and outcome in CHF patients with an extraordinary complication with biliary sepsis. Our case described a 23-year-old female diagnosed as CHF combined with biliary sepsis. Her blood culture was positive for KP (Klebsiella pneumoniae), and with a high level of CA19-9 (> 1200.00 U/ml, ref: <37.00 U/ml). Meanwhile, her imaging examinations showed intrahepatic bile duct dilatation, portal hypertension, splenomegaly, and renal cysts. Liver pathology revealed periportal fibrosis and irregularly shaped proliferating bile ducts. Whole-exome sequencing identified two heterozygous missense variants c.3860T > G (p. V1287G) and c.9059T > C (p. L3020P) in PKHD1 gene. After biliary sepsis relieved, her liver function test was normal, and imaging examination results showed no significant difference with the results harvested during her biliary sepsis occurred.

CONCLUSION

The diagnosis of CHF complicated with biliary sepsis in the patient was made. Severely biliary sepsis due to KP infection may not inevitably aggravate congential liver abnormality in young patients. Our case provides a good reference for timely treatment of CHF patients with biliary sepsis.

Factors affecting continuous renal replacement therapy duration in critically ill patients: A retrospective study

INTRODUCTION

This study aimed to analyze the factors affecting continuous renal replacement therapy (CRRT) duration in critically ill patients and provide a reference for clinical treatment.

MATERIAL AND METHODS

We divided patients into regional citrate anti-coagulation (RCA) and low-molecular-weight-heparin (LMWH) groups according to the anti-coagulation method and collected the relevant data, to analyze the factors associated with CRRT time.

RESULTS

Compared with the LMWH group, the RCA group had a longer mean treatment time (55.36 ± 22.57 vs. 37.65 ± 27.09 h, p < 0.001), lower transmembrane pressure, and lower filter pressure, regardless of vascular access site. Multivariable linear regression analysis showed a significant correlation between anti-coagulation patterns, filter pressure at CRRT discontinuation, nurses' level of intensive care unit experience, pre-machine fibrinogen level, and CRRT time.

CONCLUSION

Anti-coagulation is the most important factor affecting CRRT duration. Filter pressure, nurses' level of intensive care unit experience, and fibrinogen level also affecting CRRT duration.

Association between minimal decrease in platelet counts and outcomes in septic patients: a retrospective observational study

OBJECTIVES

Although platelets have been linked to inflammatory development in sepsis, knowledge on their role as an indicator in sepsis treatment is scarce. Here, we investigated the association between time-dependent changes in platelet counts with mortality rates to reveal the role of platelets in sepsis therapy.

DESIGN

A retrospective cohort study.

SETTING

We screened the Medical Information Mart for Intensive Care (MIMIC-IV), a public database comprising data from critical care subjects at the Beth Israel Deaconess Medical Center (BIDMC) in Boston, Massachusetts, USA.

PARTICIPANTS

A total of 7981 patients, who were admitted to the BIDMC between 2008 and 2019, were analysed based on Sepsis-3 criteria from MIMIC-IV.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary and secondary outcomes included 30-day mortality after admission and length of intensive care unit (ICU) stay and hospitalisation, respectively.

RESULTS

Patients with ≤10% reduction in proportion of platelet counts were associated with significantly lower 30-day mortality (14.1% vs 23.5%, p<0.001, Kaplan-Meier analysis, p<0.0001). Multivariable analysis revealed that decreased platelet-count percentage ≤10% on day 4 after ICU admission was associated with lower probability of 30-day non-survival (OR=0.73, 95% CI 0.64 to 0.82, p＜0.001). Patients in the ≤10% group had significantly shorter ICU stays than those in the >10% group (6.8 vs 7.5, p＜0.001). Restricted cubic spline curves revealed that mortality rates decreased with increase in proportion of platelet counts.

CONCLUSIONS

A ≤10% decrease in platelet-count percentage among sepsis patients after treatments is independently associated with decreased 30-day mortality, suggesting that changes in proportion of platelet counts after treatments could be an indicator for assessing the therapeutic effects of sepsis.

Hirsutine, a novel megakaryopoiesis inducer, promotes thrombopoiesis via MEK/ERK/FOG1/TAL1 signaling

BACKGROUND

Thrombocytopenia (TP) remains a challenge in clinical hematology. TP may have serious consequences, such as recurrent skin and mucosal bleeding and increased risk of intracranial and internal organ hemorrhage. However, effective and safe therapeutic drugs for the long-term management of TP are still lacking.

PURPOSE

This study aimed to identify more effective active compounds for TP therapy.

METHODS

Liquid chromatography-mass spectrometry-nuclear magnetic resonance analysis was used to confirm the medicinal species and chemical structure of Hirsutine (HS). The proliferation of HS was examined by Cell Counting Kit (CCK-8) assay on cells lines. The effect of HS on megakaryocyte differentiation was analyzed by evaluating the expression of CD41, CD42b, and DNA ploidy via flow cytometry (FCM). The morphology of megakaryocytes and intermediate cells was observed using an optical microscope. K562 cells were then stained with Giemsa and benzidine. qRT-PCR was used to examine the mRNA expression of GATA-1, GATA-2, FOG-1, TAL-1, RUNX-1, NF-E2, and KLF-1 in K562 cells. Protein levels of the transcription factors were analyzed by western blotting. An MEK inhibitor was used to verify the relationship between the MEK/ERK signaling pathway and CD41/CD42b (FCM), FOG-1, and TAL-1. The Kunming thrombocytopenia mouse model was established by X-ray irradiation (4 Gy) and used to test HS activity and related hematopoietic organ index in vivo. Finally, computer simulations of molecular docking were used to predict the binding energies between HS-MEK and HS-ERK.

RESULTS

We preliminarily identified HS by screening a plant-sourced compound library for natural compounds with megakaryocytic differentiation and maturation (MKD/MKM)-promoting activity. We found that HS not only enhanced MKD/MKM of K562 and Meg01 cells, but also suppressed the decline of peripheral platelet levels in X-ray-induced myelosuppressive mice. In addition, HS promoted MKD via activation of MEK-ERK-FOG1/TAL1 signaling, which may be the key molecular mechanism of HS action in TP treatment. Molecular docking simulations further verified that HS targets the signaling protein MEK with high-affinity.

CONCLUSION

In this study, we report for the first time that hirsutine boosts MKD/MKM through the MEK/ERK/FOG1/TAL1 signaling pathway and thus represents a promising treatment option for TP.

Correlation between thrombopoietin and inflammatory factors, platelet indices, and thrombosis in patients with sepsis: A retrospective study

BACKGROUND

Thrombopoietin (TPO) is a primary regulator of thrombopoiesis in physiological conditions. TPO, in combination with its specific cytokine receptor c-Mpl, drives platelet production by inducing the proliferation and differentiation of megakaryocytes. However, the role of TPO in sepsis is not well determined. The elevated levels of TPO are often accompanied by a decrease of platelet count (PLT) in systemic infected conditions, which is contrary to the view that TPO promotes platelet production under physiological conditions. In addition, whether TPO mediates organ damage in sepsis remains controversial.

AIM

To explore the relationships between TPO and inflammatory factors, platelet indices, and thrombotic indicators in sepsis.

METHODS

A total of 90 patients with sepsis diagnosed and treated at the emergency medicine department of The First People’s Hospital of Foshan between January 2020 and March 2021 were enrolled in this study. In addition, 110 patients without sepsis who came to the emergency medicine department were included as controls. Clinical and laboratory parameters including age, gender, TPO, blood cell count in peripheral blood, platelet indices, inflammatory factors such as high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-21, and IL-6, organ damage indicators, and thrombotic indicators were collected and analyzed by using various statistical approaches.

RESULTS

The results showed that the TPO levels were higher in the sepsis group than in controls [86.45 (30.55, 193.1) vs 12.45 (0.64, 46.09) pg/mL, P < 0.001], but PLT was lower (P < 0.001). Multivariable analysis showed that white blood cell count (WBC) [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.01-1.722; P = 0.044], TPO (OR = 1.02; 95%CI: 1.01-1.04; P = 0.009), IL-21 (OR = 1.02; 95%CI: 1.00-1.03; P = 0.019), troponin I (OR = 55.20; 95%CI: 5.69-535.90; P = 0.001), and prothrombin time (PT) (OR = 2.24; 95%CI: 1.10-4.55; P = 0.027) were independent risk factors associated with sepsis. TPO levels were positively correlated with IL-21, IL-6, hs-CRP, creatinine, D-dimer, PT, activated prothrombin time, international normalized ratio, fibrinogen, WBC count, and neutrophil count, and negatively correlated with PLT, thrombin time, red blood cell count, and hemoglobin concentration (P < 0.05). Receiver operating characteristic analysis showed that TPO had fair predictive value in distinguishing septic patients and non-septic patients (the area under the curve: 0.788; 95%CI: 0.723-0.852; P < 0.001). With an optimized cutoff value (28.51 pg/mL), TPO had the highest sensitivity (79%) and specificity (65%).

CONCLUSION

TPO levels are independently associated with sepsis. High TPO levels and low PLT suggest that TPO might be an acute-phase response protein in patients with infection.

Association between platelets and in-hospital mortality in critically ill patients with tumours: a retrospective cohort study

OBJECTIVES

Platelet count is an independent predictor of mortality in patients with cancer. It remains unknown whether the platelet count is related to in-hospital mortality in severely ill patients with tumours.

DESIGN

A retrospective study based on a dataset from a multicentre cohort.

SETTING

This was a secondary analysis of data from one Electronic Intensive Care Unit Collaborative Research Database survey cycle (2014-2015).

PARTICIPANTS

The data pertaining to severely ill patients with tumours were collected from 208 hospitals located across the USA. This study initially a total of 200 859 participants. After the population was limited to patients with combined tumours and platelet deficiencies, the remaining 2628 people were included in the final data analysis.

PRIMARY AND SECONDARY OUTCOME MEASURES

The main measure was the platelet count, and the main outcome was in-hospital mortality.

RESULTS

After adjustment for the covariates, the platelet count had a curvilinear relationship with in-hospital mortality (p<0.001). The first inflection point was 18.4 (per 10 change). On the left side of the first inflection point (platelet count ≤184 'x10ˆ9/L), an increase of 10 in the platelet count was negatively associated with in-hospital mortality (OR 0.92, 95% CI 0.89 to 0.95, p<0.001). The second inflection point was 44.5 (per 10 change). Additional increases of 10 in the platelet count thereafter were positively associated with hospital mortality (OR 1.13, 95% CI 1.00 to 1.28, p=0.0454). The baseline platelet count was in the range of 184 'x10ˆ9/L-445 'x10ˆ9/L(p=0.0525), and the hospital mortality was lower than the baseline platelet count in other ranges.

CONCLUSIONS

The relationship between platelet count and in-hospital mortality in critically ill patients with tumours was curvilinear. The lowest in-hospital mortality was associated with platelet count between 184 'x10ˆ9/Land 445 'x10ˆ9/L. This indicates that both high and low platelet count should receive attention in clinical practice.

Atorvastatin improves bone marrow endothelial progenitor cell function from patients with immune-related hemocytopenia

Background

Immune-related hemocytopenia (IRH) is a type of autoimmune disease that targets bone marrow hematopoietic cells. This study investigated the influence of atorvastatin on the functional aspects of bone marrow endothelial progenitor cells (BM EPCs) in IRH patients.

Methods

BM EPCs were isolated from 15 patients with IRH and 20 normal controls. The isolated BM EPCs were characterized by flow cytometry. Cell counting kit-8, flow cytometry, and Transwell migration assays were used to determine the proliferation, apoptosis, and migration of BM EPCs, respectively. Protein levels were determined by western blot assay.

Results

The BM EPCs isolated from IRH patients showed reduced proliferation, increased apoptosis, and attenuated migratory ability compared to those from normal controls. Western blot analysis showed that the protein level of p-p38 was significantly increased, while that of Phosphorylated protein kinase B (p-AKT) was significantly decreased in the BM EPCs from IRH patients, compared to BM EPCs from healthy subjects. Cell proliferation and migration were significantly enhanced by atorvastatin, recombinant human thrombopoietin, and SB20358 compared to the untreated BM EPCs from IRH patients. Atorvastatin, Recombinant human thrombopoietin (TPO), and SB20358 treatment significantly suppressed the protein levels of p-p38 protein, but increased those of p-AKT in BM EPCS from IRH patients.

Conclusions

In summary, atorvastatin increases the number and function of BM EPCs in IRH patients by regulating the p38 and AKT signaling pathways.