Helicobacter pylori infection and risk of salmonella infection

Helicobacter pylori (H pylori) infection is the most frequent infection worldwide and it has been postulated that it predisposes to multiple enteric pathogens and diarrheal diseases. Salmonella infection is common in tropical and under developed communities and is associated with wide range of diseases from gastroenteritis to typhoid fever. This study aimed at detecting the impact of H pylori infection on the incidence of salmonella infections. The study participants were sampled from cohorts of patients in four university hospitals in different Egyptian Governorates. Their age ranged from 20 to 59 years and followed up for a rising Widal test. Case patients (n = 109) were subjects who visited the outpatient clinic because of diarrhea and typhoid like illness. They were either positive for H pylori stool antigen (n = 53) or negative to it (n = 56). All patients were subjected to thorough history taking, clinical examination, routine laboratory investigations, abdominal ultrasonography, H pylori stool antigen detection, and serial Widal test assay. The proportion of salmonella-infected subjects was lower among case patients with H pylori infection (22.6%) than among those negative for H pylori (33.9%) albeit not statistically significant (adjusted odds ratio [OR], 0.57; 95% confidence interval [CI], 0.24–1.33; P = .21). The association persisted nonsignificant after adjusting for sociodemographic variables (adjusted OR, 0.5; 95% CI, 0.18–1.39; P = .18). In a multivariate analysis that adjusted for sex, dietary habits, socioeconomic status, and educational level subjects who eat outdoors were associated with a significantly greater risk of salmonella typhi infection. Our findings suggest that there is no association between H pylori infection and salmonella infection in patients presented with typhoid fever or typhoid like illness.