Helicobacter pylori in Africa:: Observations on an 'enigma within an enigma'

Background: We conducted a retrospective literature review of all the data published on Helicobacter pylori in Africa in order to test whether the prevalence of diseases associated with this organism differs from that in developed nations. Methods: Both sero-epidemiological (n = 8) as well as prospective endoscopic studies in subjects with either dyspepsia or epigastric pain (n = 23) and one retrospective study were available for analysis. Results: Sero-epidemiology confirmed both the early age of acquisition in children (50% by 10 years) as well as the high prevalence of the organism (61%) in adult asymptomatic individuals. Endoscopic studies in dyspeptic individuals revealed the presence of the organism in 72%. Duodenal ulceration was noted in 26% of 3473 cases and in these, H. pylori was present in 90%. An association of gastric meta-plasia with duodenal ulceration was identified in the one study in which it was investigated. Gastric ulceration occurred approximately four-fold less frequently (7% of 2286 cases) than duodenal ulceration and the organism was evident in 75% of the gastric ulceration cases. Findings of intestinal metaplasia (14%) and gastric cancer (3.4%) were not infrequent, but the paucity of accurate epidemiological data made it difficult to establish a correlation between the two. Conclusion: It would appear that prospective endoscopic-based studies in African subjects may question the standard dogma of a low prevalence of H. pylori-associated diseases in Africa. Further research is clearly required. (C) 1999 Blackwell Science Asia Pty Ltd.