Introduction
Immune thrombocytopenia (ITP) is an autoimmune disease defined by a
platelet count less than 100 × 109/L due to
immune-mediated destruction of platelets with inadequate platelet
production.1 ITP can occur as a primary in the absence
of obvious underlying causes or as a secondary due to an underlying
disease or a medication exposure. The majority of ITP patients are
asymptomatic or present with mucocutaneous bleeding at the time of
diagnosis. However, life-threatening bleeding can be the initial
presentation, but still rare.2 Diagnosis of ITP is
usually made clinically by excluding other causes of thrombocytopenia.
Chronic ITP is characterized by persistent thrombocytopenia for 12
months or more.1
Several viral agents have been previously implicated as pathogenic
triggers for secondary ITP.3 Since the identification
of the novel coronavirus at the end of 2019, and thrombocytopenia was
considered as a risk factor associated with poor COVID-19
outcomes.4 Several case reports and case series of ITP
secondary to COVID-19 have been published5, 6,
however, only two small-sized reports in the literature have reviewed
the consequences of COVID-19 in patients previously diagnosed with
chronic ITP.4, 7 For that reason, we designed a
retrospective cohort study to investigate the clinical impacts of
COVID-19 infection on the admitted patients to the hospital who
previously diagnosed with chronic ITP.