Immune thrombocytopenia following multisystem inflammatory syndrome in children (MIS-C) - a case series

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.

Prolonged Thrombocytopenia in a Case of MIS-C in a Vaccinated Child

Multisystem inflammatory syndrome in children (MIS-C) has been extensively described in patients following severe acute respiratory syndrome coronavirus 2 infection. There are now questions about what MIS-C may look like in vaccinated children. Multisystem inflammatory syndrome in children has many clinical and laboratory features in common with other inflammatory disorders including Kawasaki disease and toxic shock syndrome. Rheumatologic conditions can present with similar musculoskeletal complaints and elevated inflammatory markers. Laboratory markers and clinical symptoms of MIS-C usually improve once therapy is begun. We describe a child with persistent thrombocytopenia as an example of variable presentation of MIS-C in vaccinated children. This case report discusses an atypical progression of MIS-C in a vaccinated child with a known prior positive COVID-19 polymerase chain reaction (PCR) test. She presented with nonspecific abdominal pain and fever and was found to have elevated inflammatory markers, lymphopenia, and thrombocytopenia. Intravenous immunoglobulin and steroid treatment failed to induce rapid recovery in her clinical condition or thrombocytopenia. Rheumatologic, hematologic, oncologic, and infectious causes were considered and worked up due to the uncertainty of her case and persistence of pancytopenia but ultimately were ruled out with extensive testing and monitoring. It was key to include a broad differential including viral-induced bone marrow suppression, idiopathic thrombocytopenic purpura, secondary hemophagocytic lymphohistiocytosis, systemic juvenile idiopathic arthritis, and malignancy. The spectrum of MIS-C and response to treatment continues to evolve, and prior vaccination in this child's case complicated the clinical picture further. Additional evaluation of MIS-C in vaccinated cases will permit characterization of the range of MIS-C presentation and response to standard therapy.

Severe Thrombocytopenic Purpura Associated with COVID-19 in a Pediatric Patient

Purpose

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to cause a diverse spectrum of clinical manifestations ranging from mild, flu-like symptoms to severe progressive pneumonia, acute respiratory distress syndrome with or without other extrapulmonary impairment. Hematological changes such as lymphopenia, neutrophilia, and anemia as the disease progresses, are frequently found in COVID-19. Thrombocytopenia may be drug-induced or can occur secondary to sepsis, disseminated intravascular coagulation or bone marrow suppression. Immune thrombocytopenic purpura (ITP) is frequently observed in children aged 2-5 years and in 60% of cases may proceed an upper respiratory tract infection. The present paper aimed to raise awareness of ITP as a possible pediatric presentation of coronavirus disease.

Patients and Methods

We present the case of previously healthy, eight-year-old female patient, who developed an immune thrombocytopenia flare, also known as immune thrombocytopenic purpura (ITP), in the context of COVID-19, with diffuse petechiae and ecchymosis on her body, face and oral mucosa, and a nadir platelet count of 0×10³/μL.

Results

Platelet count recovery was observed after seven days of combined treatment with intravenous immunoglobulin (IVIG) and corticosteroids.

Conclusion

The growing body of literature regarding the clinical and laboratory manifestations of COVID-19 infection in children, has reported thrombocytopenia in relation to unfavorable disease progression or multisystem inflammatory syndrome (MIS-C). Clinicians must be aware that ITP may appear both in mild and severe COVID-19, at any time during its course, and can be associated with a higher bleeding risk, thus its diagnostic may be critical.

SARS-CoV-2 and Autoimmune Cytopenia

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with a variety of clinical manifestations related to viral tissue damage, as well as a virally induced immune response. Hyperstimulation of the immune system can serve as a trigger for autoimmunity. Several immune-mediated manifestations have been described in the course of SARS-CoV-2 infection. Immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA) are the most common hematologic autoimmune disorders seen in the course of SARS-CoV-2 infection. Vaccine-induced thrombocytopenia is a unique autoimmune hematologic cytopenia associated with SARS-CoV-2 vaccination. This paper will review the current literature on the association of SARS-CoV-2 infection and vaccination with autoimmune cytopenias and the clinical course of autoimmune cytopenias in patients with COVID-19.

Untangling the Intricacies of Infection, Thrombosis, Vaccination, and Antiphospholipid Antibodies for COVID-19

Advanced SARS-CoV-2 infections not uncommonly associate with the occurrence of silent or manifest thrombotic events which may be found as focal or systemic disease. Given the potential complexity of COVID-19 illnesses, a multifactorial causation is likely, but several studies have focused on infection-induced coagulopathy. Procoagulant states are commonly found in association with the finding of antiphospholipid antibodies. The correlation of the latter with thrombosis and/or clinical severity remains controversial. Although measures of antiphospholipid antibodies most commonly include assessments for lupus anticoagulant, anticardiolipin, and anti-ß2-glycoprotein-I antibodies, lesser common antibodies have been detected, and there remains speculation that other yet undiscovered autoimmune thrombotic events may yet be found. The recent discovery of post-vaccination thromboses associated with platelet factor 4 antibody has created another level of concern. The pathogenesis of antiphospholipid antibodies and their role in COVID-19-related thrombosis deserves further attention. The multifactorial nature of thrombosis associated with both infection and vaccination should continue to be studied as new events unfold. Even if a cause-and-effect relationship is variable at best, such dedicated research is likely to generate other valuable insights that are applicable to medicine generally.