CagA seropositivity and the severity of Helicobacter pylori infection in dyspeptic children

Aim: To assess the incidence of cagA (cytotoxin-associated protein) and to evaluate its correlation with endoscopic-histologic findings and with eradication rate in a series of children affected by Helicobacter pylori (H. pylori) gastritis. Methods: Fifty consecutive H. pylori gastritis children (27M; median age 10 y and 11 mo) were tested for IgG cagA protein (Western Blot technique). Pretreatment H. pylori infection was assessed on the grounds of endoscopic antral biopsy specimens by means of rapid urease test and histologic examination (Giemsa staining). All the children were treated with omeprazole (1 mg/kg/d), clarithromycin (15 mg/kg/d) and amoxycillin (50 mg/kg/d) for 2 wk. According to universally accepted clinical practice, outcome of treatment was assessed by C-13 urea breath test at least 6 wk after the end of therapy. Results: Thirty-five children (70%) were seropositive to cagA+ protein (median age 11 y and 1 mo). Endoscopic findings of cagA+ patients were similar to those of cagA- patients. In cagA seropositive patients the severity of histologic gastritis was higher (p < 0.05) and the granulocytic infiltration more marked (p < 0.01) than in seronegative ones. In cagA+ children, PI. pylori eradication rate was significantly lower (p < 0.02). Conclusions: cagA testing may be of useful clinical interest because its positivity can imply a more severe gastritis and a lower susceptibility to eradication treatment.