Immune Thrombocytopenia Induced by Helicobacter pylori Infection: A Case Report and Literature Review

Abstract

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by the production of autoantibodies against the platelet surface antigens. ITP is a diagnosis of exclusion and is further categorized into primary and secondary ITP. The etiology of primary ITP is idiopathic, and secondary ITP is caused by infections and autoimmune disorders. Among infectious etiology of ITP, human immunodeficiency virus, herpes virus, and hepatitis B and C virus are common. Helicobacter pylori (H. pylori) is a rare cause of ITP, and the relationship between ITP and H. pylori is highlighted in the literature. We report a case of ITP in an adult female who presented with hematemesis and petechial rash in the lower limbs. Her initial laboratory results demonstrated thrombocytopenia, and the results of her gastric biopsy and stool antigen were positive for H. pylori. She was diagnosed with ITP induced by H. pylori because additional causes of ITP were not identified. Her clinical improvement and platelet recovery after initiating H. pylori eradication therapy were consistent with H. pylori-induced ITP.

Impact of Helicobacter pylori Infection upon the Evolution and Outcome of Pediatric Immune Thrombocytopenic Purpura: A Comprehensive Review

“…In similar fashion, around 20% of children cases can be attributed to secondary causes, according to a Spanish study [16]. H. pylori has been regarded as one of the potential causes of secondary ITP, but it is yet unclear whether treatment of this particular infection might be sufficient to improve platelet numbers [17,18]. There are several hypotheses that link H. pylori to ITP.…”

Immune Thrombocytopenic Purpura Associated With Systemic Lupus Erythematosus, Helicobacter pylori, and Hepatitis B

“…The pathogenesis of ITP-HP is theorized to involve molecular mimicry, where HP produces antibodies that cross-react with platelets [ 4 ]. Geographic variation in the virulence genes of Helicobacter pylori (HP), specifically the vacuolating cytotoxin gene A (VacA) and cytotoxin-associated gene A (cagA) has been observed [ 11 ]. This variation is associated with the incidence of immune thrombocytopenia associated with H. pylori infection (ITP-HP) [ 10 , 11 ].…”

“…Geographic variation in the virulence genes of Helicobacter pylori (HP), specifically the vacuolating cytotoxin gene A (VacA) and cytotoxin-associated gene A (cagA) has been observed [ 11 ]. This variation is associated with the incidence of immune thrombocytopenia associated with H. pylori infection (ITP-HP) [ 10 , 11 ]. The prevalence of HP infection among ITP patients is similar to that of the general population when considering age and location [ 1 , 6 ].…”

“…The prevalence of HP infection among ITP patients is similar to that of the general population when considering age and location [ 1 , 6 ]. However, only a tiny fraction of infected individuals develop ITP-HP [ 11 ]. Platelet response to documented bacterial eradication varies across studies, ranging from 0% to 7% in the US series and up to 100% in the Japanese series [ 10 - 12 ].…”

“…Successful bacterial eradication has been shown to provide benefits compared to unsuccessful or no eradication [ 12 , 13 ]. Failure to correct thrombocytopenia in some cases is associated with the emergence of antigen-independent autoreactive clones of T and B cells [ 11 , 13 ]. HP infection may also affect the balance of activating and inhibiting FcγRs (Fc gamma receptors), and platelet levels often increase within a few weeks of antibiotic treatment, potentially due to the restoration of this balance [ 11 - 13 ].…”