Ethnic and Racial Difference In H.Pylori Infection In Patients With ITP Treated At A MAJOR Tertiary Medical Center In LOS Angeles

Infection with Helicobacter pylori has been implicated as an etiologic agent for the development of immune thrombocytopenia (ITP). In a systematic review of the medical literature Stasi and colleagues reported wide regional variation in the prevalence of H. pylori infection in ITP patients with significant differences in improvement in platelet count with infection eradication. The largest report on H.pylori infection in ITP patients diagnosed in the United States found a lower prevalence of infection (21.6%) than the reported seroprevalence (32.5%) for the general United States population.¹ Only 1 of 15 treated patients responded eradication of their infection.¹ Based upon this report the American Society of Hematology ITP guidelines do not recommend routine H. pylori testing during the evaluation of newly diagnosed patients. Los Angeles County-University of Southern California Medical Center is the largest healthcare provider in the metropolitan Los Angeles region. It services a large and ethically diverse patient population. Screening for H.pylori infection in newly diagnosed and previously diagnosed ITP patients was begun as a routine part of the diagnostic algorithm in 2008. We initiated a retrospective review of H.pylori infection in patients screened during this period.

At the time of this report the medical records of 80 ITP patients (M/F: 22/58) have been reviewed. 68 (F/M: 52/16) patients, 51 with 1^o ITP and 17 with 2^ry ITP, were screened for H.pylori. The median age of the screened patients was 50 yrs (23 to 85 yrs). Patients were screened with either the H. pylori stool antigen (46 pts; 65%) or H. pylori Breath test (10 pts; 16%). 12 patients (19%) were only screened for H.pylori antibodies. Of the screened patients, 29/68 (42.6%) tested positive for H. pylori. However, there were significant ethnic and racial differences in the prevalence of infection (Table ). 27 of the 29 positive patients were treated for their infection. H. Pylori eradication was documented in 20 of 22 (91%). An additional patient was successfully treated with a second course of antibiotics. Response to therapy could not be assessed in 14 of the 27 treated patients due to treatment with concomitant ITP medications. Of the 13 patients who could be evaluated for response using IWG criteria, there were 4 (30.8%) complete responses, 1 (7.7%) partial response and no response in 8 (61.5%). All complete responders were treated within 2 months of initial presentation. At the time of this report only 3 of the 29 patients remain on ITP treatment.

There are significant ethnic and racial differences in the prevalence of H. pylori infection in ITP patients diagnosed in the greater Los Angeles metropolitan region. Despite earlier reports from New York and Miami, early identification and treatment of H. pylori infected may result in remissions up to a third of patients.

1. Michel M et al. Blood 2004; 103: 890-896.

No relevant conflicts of interest to declare.