Secondary Immune Thrombocytopenic Purpura Triggered by COVID-19

Abstract

Multiple infectious causes have been implicated with the development of secondary immune thrombocytopenic purpura (ITP). Nevertheless, new pathogens, including coronavirus disease 2019 (COVID-19), are recently being described in its development. A 41-year-old Hispanic male presented to the Emergency Department with a two-day history of bleeding gums and blood-tinged sputum. A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) test was positive on admission. Initial laboratory studies showed severe thrombocytopenia of 3x10 9 /L (150-400x10 9 /L) with no abnormal platelets or schistocytes seen on peripheral blood smear, with normal prothrombin time/international normalized ratio (PT/INR), partial thromboplastin time (PTT) and fibrinogen levels. Secondary causes of thrombocytopenia were ruled out. One unit of single donor platelets was transfused and the patient was treated with intravenous dexamethasone for a total of five days and intravenous immunoglobulin (IVIG) for two days. One week after discharge the patient had a recurrence of epistaxis and hematuria requiring a second course of steroids and IVIG and the decision was made to start the patient on eltrombopag 50mg daily, which maintained his platelet counts within normal limits. COVID-19-associated ITP can be severe and life-threatening and hence warrants rapid and prompt management with steroids and IVIG. In refractory cases, thrombopoietin receptor agonists should be used.

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

“…As demonstrated in this report, ITP can manifest several weeks after the initial diagnosis of COVID-19. While initial reports primarily linked ITP to vaccination, recent literature has also reported associations between ITP and COVID-19 infection [3][4][5][6][7][8][9][10]. In the presented case, the time gap between the initial positive COVID-19 test and the diagnosis of ITP was approximately five weeks, which is compatible with another report of COVID-19-associated ITP [7][8][9][10].…”

“…More recently, ITP has been linked to COVID-19 infection, both at the time of infection and in the weeks following disease onset. There have been reports of ITP diagnosis occurring as late as five weeks and even up to 125 days after the initial COVID-19 diagnosis [3][4][5][6][7][8][9][10]. This potential association prompted the British Society for Haematology to issue guidelines concerning treatment options for ITP cases in the context of COVID-19 infection [3].…”

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

“…Thrombocytopenia in COVID-19 patients resembles immune thrombocytopenia (ITP), where hTPO and/or its receptor are mistakenly targeted by autoantibodies leading to reduced platelet count [ 55 ]. Treatments with hTPO Receptor Agonists improve thrombocytopenia in both general [ 56 ] and COVID-19 [ 57 ] patients, suggesting the mistaken targeting occurs before hTPO activates the hTPO receptor. ITP is a heterogenous disease caused by numerous mechanisms.…”

Potential autoimmunity resulting from molecular mimicry between SARS-CoV-2 Spike and human proteins

“…Thrombocytopenia in COVID-19 patients resembles immune thrombocytopenia, where hTPO and/or its receptor are mistakenly targeted by autoantibodies leading to reduced platelet count (Nazy et al, 2018). Treatments with hTPO Receptor Agonists improve thrombocytopenia in both general (Audia and Bonnotte, 2021) and COVID-19 (Watts et al, 2021) patients, suggesting the mistaken targeting occurs before hTPO activates the hTPO receptor. For ELDKY, we identified one 3D-mimic in the fusion F0 glycoprotein of respiratory syncytial virus (Table 2) and two AF- 3D-mimics from keratin type I cytoskeletal 18 and tropomyosin alpha-3 (Table 3).…”

“…Thrombocytopenia in COVID-19 patients resembles immune thrombocytopenia, where human thrombopoietin (hTPO) and/or its receptor are mistakenly targeted by autoantibodies leading to reduced platelet count (Nazy et al 2018). Treatments with TPO Receptor Agonists improve thrombocytopenia in both general (Audia and Bonnotte 2021) and COVID-19 (Watts et al 2021) patients, suggesting the mistaken targeting occurs before TPO activates the TPO receptor.…”