"Ultrastructural changes of platelets in COVID-19 and chronic viral hepatitis patients "

Area of Science:

• Hematology
• Virology
• Immunology

Background:

• Coagulation disorders are a significant consequence of COVID-19.
• Chronic viral hepatitis infections commonly cause coagulation factor defects, thrombocytopenia, and platelet dysfunction.
• Dual infections with SARS-CoV-2 and chronic viral hepatitis are plausible, particularly in endemic regions.

Purpose of the Study:

• To investigate platelet ultrastructural changes in COVID-19 patients.
• To quantify serum levels of Platelet Factor-4 (PF-4), ferritin, C-reactive protein (CRP), and D-dimer.
• To assess the impact of co-existing chronic viral hepatitis on these parameters.

Main Methods:

• Comparative analysis of COVID-19 patients (n=60), COVID-19 with chronic viral hepatitis patients (n=20), and healthy controls (n=20).
• Electron microscopy for evaluating platelet ultrastructural morphology.
• Serum biochemical assays for PF-4, ferritin, CRP, and D-dimer quantification.

Main Results:

• Ultrastructural platelet activation was observed in all patient groups.
• Chronic viral hepatitis patients exhibited platelet ultrastructural apoptotic changes.
• Significantly elevated PF-4 levels in moderate to severe COVID-19 (P<0.001), with a predictive cutoff of 17 ng/ml.
• PF-4 positively correlated with ferritin, CRP, and D-dimer (P<0.001), and negatively with platelet and granule counts (P<0.001).
• Patients with dual infections showed mild COVID-19 symptoms and PF-4 levels similar to mild COVID-19 cases.

Conclusions:

• Platelet activation and ultrastructural changes are critical in COVID-19 coagulopathy and chronic viral hepatitis.
• Elevated PF-4 serves as a sensitive biomarker for COVID-19 severity and correlates with key inflammatory and coagulation markers.
• Dual viral infections impose a significant burden on platelet function, highlighting the need for vigilant coagulation monitoring.