[Variation of Helicobacter pylori prevalence and its relation with the level of chlorine in the water at the "Atarjea" plant, Lima, Perú. Period 1985-2002].
OBJECTIVE
Relate the variation in the prevalence of Helicobacter pylori in patients from medium and high socio-economic levels, suffering from chronic active gastritis (CAG) and peptic ulcer, from 1985 to 2002, in Lima, Peru with the content levels of chlorine in the water at the "Atarjea" Water Treatment Plant.


METHODS
A total of 1,815 patients showing upper gastrointestinal tract symptoms were examined by esophago-gastro-duodenoscopy, excluding those patients who during the past four weeks had been treated with antibiotics, H2 receptor blockers and proton pump inhibitors. The variation of the H. pylori infection prevalence was compared to the content levels of chlorine in the water at the "Atarjea" plant.


RESULTS
A total of 1,290 patients with CAG were identified; 178 with duodenal ulcer; 55 with gastric ulcer and 292 with histologically normal gastric mucose (HNGM). The prevalence of H. pylori in patients with CAG dropped from 83.3% to 58.7% (p<0.001). In patients with duodenal ulcer, it decreased from 89.5% to 71.9% (p=0.004) and in those with gastric ulcer, from 84.8% to 77.3% (p=0.36). In patients with HNGM prevalence remained the same (from 2.7% to 0.0%) (p=0.15). The chlorine content levels at the water of "Atarjea" plant remained relatively stable from 1991 to 2000. No correlation was found with the prevalence of Helicobacter pylori (p>0.05).


CONCLUSIONS
Between 1985 and 2002, prevalence of Helicobacter pylori with chronic active gastritis (CAG) and/or peptic ulcer in patients from the medium and upper socio-economic strata, diminished. No correlation was found between the chlorine content levels in the water treated at the "Atarjea" plant and the decrease of this prevalence.
Ramírez R
Alberto
A
Universidad Peruana Cayetano Heredia, Peru.
Chinga A
Erick
E
Mendoza R
Daniel
D
D000293:Adolescent; D000328:Adult; D000368:Aged; D002713:Chlorine / Q000032:analysis; D005260:Female; D005756:Gastritis / Q000453:epidemiology* / Q000382:microbiology; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000453:epidemiology* / Q000382:microbiology; D010568:Peru / Q000453:epidemiology; D015995:Prevalence; D012959:Socioeconomic Factors; D014867:Water / Q000737:chemistry
D014867:Water; D002713:Chlorine