Secondary Immune Thrombocytopenic Purpura Triggered by COVID-19

SARS-CoV-2 infection-induced immune thrombocytopenia: a systematic review of current reports

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by a low platelet count with increased risk of bleeding, and viral infection may trigger ITP. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-induced ITP has been increasingly reported. We systemically reviewed the previously reported cases of SARS-CoV-2 infection-induced ITP and identified a total of 105 patients from 68 studies. The median age was 61 years, and 14 patients (12%) were < 18 years old (pediatric cases). In adult cases, a total of 53% patients were classified as moderate to severe SARS-CoV-2 infection. The median platelet count at diagnosis and nadir were 6,000/µL and 4,000/µL, respectively. When comparing platelet levels between non-severe SARS-CoV-2 infection and moderate to severe SARS-CoV-2 infection, the median values of platelet levels at diagnosis were not significantly different between the groups (4,000/µL in non-severe SARS-CoV-2 infection and 9,000/µL in moderate to severe SARS-CoV-2 infection, p-value = 0.22). Median nadir platelet levels were also not significantly different between groups (4,000/µL in non-severe SARS-CoV-2 infection and 8,000/µL in moderate to severe SARS-CoV-2 infection, p-value = 0.27). More than half of the cases (53 patients) were treated with combination therapy including steroid, intravenous immunoglobulin, and eltrombopag. Major bleeding and intracranial hemorrhage occurred in ten (11%) and six (6.6%) cases, respectively. The overall mortality rate was 7%. In pediatric cases, none of the patients experienced major bleeding and lethal outcomes.

Immune Thrombocytopenia Purpura Associated With COVID-19 Infection: A Challenging Diagnosis and Management

The COVID-19 pandemic has posed unprecedented challenges in the field of medicine. Among its diverse manifestations, immune thrombocytopenia purpura (ITP) has emerged as a complication associated with COVID-19 infection. This case report presents a 90-year-old Caucasian male with a history of COVID-19 infection who developed acute hemoptysis, thrombocytopenia, and purpura. The diagnosis of ITP confirmed through exclusion criteria and clinical evaluation, occurred several weeks after the initial COVID-19 diagnosis. Differential diagnoses, including drug-induced thrombocytopenia, were carefully considered and excluded. The reported case highlights the importance of vigilance in identifying ITP as a potential complication of COVID-19 infection, even in the post-infection period. The timely initiation of appropriate treatment proved effective in managing the patient's condition. Collaboration among medical specialties facilitated comprehensive patient care, thereby reducing hospitalization periods. This case report serves as a crucial alert to physicians, underlining the need for ongoing monitoring of COVID-19 complications, especially as testing dwindles. By fostering interdisciplinary cooperation, healthcare professionals can optimize patient outcomes and effectively manage the multifaceted challenges associated with COVID-19 infection.

Potential Autoimmunity Resulting from Molecular Mimicry between SARS-CoV-2 Spike and Human Proteins

Molecular mimicry between viral antigens and host proteins can produce cross-reacting antibodies leading to autoimmunity. The coronavirus SARS-CoV-2 causes COVID-19, a disease curiously resulting in varied symptoms and outcomes, ranging from asymptomatic to fatal. Autoimmunity due to cross-reacting antibodies resulting from molecular mimicry between viral antigens and host proteins may provide an explanation. Thus, we computationally investigated molecular mimicry between SARS-CoV-2 Spike and known epitopes. We discovered molecular mimicry hotspots in Spike and highlight two examples with tentative high autoimmune potential and implications for understanding COVID-19 complications. We show that a TQLPP motif in Spike and thrombopoietin shares similar antibody binding properties. Antibodies cross-reacting with thrombopoietin may induce thrombocytopenia, a condition observed in COVID-19 patients. Another motif, ELDKY, is shared in multiple human proteins, such as PRKG1 involved in platelet activation and calcium regulation, and tropomyosin, which is linked to cardiac disease. Antibodies cross-reacting with PRKG1 and tropomyosin may cause known COVID-19 complications such as blood-clotting disorders and cardiac disease, respectively. Our findings illuminate COVID-19 pathogenesis and highlight the importance of considering autoimmune potential when developing therapeutic interventions to reduce adverse reactions.