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A total of 300 gastric biopsy samples and 50 Helicobacter pylori isolates were collected from Ethiopian adult dyspeptic patients. The vacA and cagA genes were detected in 90 and 79% of biopsy specimens, respectively, and in 100 and 87% of clinical isolates, respectively. Both genes were detected in 84% of the gastric biopsy samples and in 87% of the clinical isolates. Among vacA genotypes, the s1/m1 genotype was the most common in gastric biopsy samples (48%). The vacA and cagA positive H. pylori strains were detected to a higher degree in patients with chronic active gastritis (71%) than patients with other histopathological findings (29%) (P < 0.05).

Presently, there is no published information on the antimicrobial susceptibility pattern of H. pylori strains in Ethiopia to guide the choice of drug for therapy. Therefore, it is becoming clinically relevant to test the in vitro susceptibility of H. pylori clinical isolates prior to treating patients. Susceptibility testing was performed on 50 clinical H. pylori isolates obtained from adult dyspeptic patients referred to the gastrointestinal (GI) Clinic of Tikur Anbassa University Hospital. Five antibiotics were evaluated, by using the Episolmeter test (E-test). The antibiogram of 50 H. pylori clinical isolates showed that all strains were sensitive to clarithromycin, erythromycin and tetracycline, while 38/50 (76%) and 3/50 (6%) of the strains were resistant to metronidazole and amoxicillin, respectively. Infection by metronidazole or amoxicillin resistant H. pylori is an important factor leading to treatment failure. Testing of all H. pylori clinical isolates to metronidazole and amoxicillin is recommended. If it is not possible to perform susceptibility tests on each clinical isolate, a program to survey the prevalence of resistance should be implemented in a given area or population. When treatment of H. pylori infection is indicated in dyspeptic patients, the potential availability, simplicity of use, safety and low cost of the antimicrobial agents have to be taken into account.

In developing countries such as Ethiopia, where chronic gastritis and peptic-ulcer disease are the most common endoscopic findings, it is important to study the association between Helicobacter pylori infection and gastroduodenal diseases. Both invasive and non-invasive diagnostic methods were therefore used to investigate 300, consecutive, adult patients with dyspepsia, from the gastrointestinal clinic of Tikur Anbassa University Hospital, Addis Ababa. The apparent overall prevalence of H. pylori infection varied according to the detection method employed. Culture revealed H. pylori in only 69% of the patients but this pathogen appeared more common when rapid urease tests (71%), PCR-denaturating gradient gel electrophoresis (91%), histopathology (81%), silver staining (75%) or stool-antigen tests (81%) were employed. Antibodies to H. pylori were detected, both by enzyme immuno-assay (EIA) and immunoblotting, in approximately 80% of the patients, whether the antigens used were of a reference strain or from a local isolate of H. pylori. When some of the EIA-positive and EIA-negative sera were cross-absorbed with antigens of Campylobacter jejuni and re-tested by EIA, the H. pylori-positive sera remained positive and the negative sera remained negative. Dyspeptic patients in Ethiopia, like most of those previously observed elsewhere in Africa, are often infected with H. pylori. It is important that the management of these patients should not be hampered by the misinterpretation of the African epidemiology of this pathogen.