Seroprevalence of Helicobacter pylori infection in patients with lymphoma

To determine the Helicobacter pylori (HP) seroprevalence in patients with n on-Hodgkin's lymphoma (NHL) and other hematological conditions. Sera were c ollected from 444 patients with NHL, Hodgkin's disease (HD), lymphoprolifer ative disorders (LPD), myeloproliferative disorders (MPD), and other hemato logical conditions. HP seropositivity was determined by ELISA and the resul ts were compared among diagnostic groups HP seropositivity was observed in 168/444 (38%) of the total population. Higher seropositivity rates were ass ociated with increasing age (p=0.001), and country of birth outside the USA and Canada (p=0.0001). Among the diagnostic groups, patients with NHL demo nstrated the highest frequency (43%) and those with HD, the lowest frequenc y (20%; p=.026) of HP seropositivity. The differences among diagnostic grou ps remained statistically significant after controlling for country of birt h (p<0.05), but not after controlling for patient age at diagnosis. The HP seroprevalence of GI NHL was 55% compared to 40% for non-GI NHL (p=NS). The highest rate of HP seropositivity (67%) occurred in gastric MALT lymphoma patients, although this: did not reach statistical significance compared to the non MALT group (50%) due to small sample size. In conclusion, the rate of HP seropositivity in patients with MALT lymphoma in the USA appears to be lower than in Europe. Helicobacter pylori does not appear to be an impor tant factor in other types of NHL of the GI tract or elsewhere. Studies of HP prevalence should be controlled for country of birth as well as for age.