Identification and Genotyping of the Etiological Agent of Tuberculous Lymphadenitis in Ethiopia

Background: In Ethiopia; little has been done to assess how Mycobacterium bovis has contributed to human tuberculosis; though the population routinely consumes unpasteurized milk and raw meat. The aim of this study was to determine the proportion of M. tuberculosis and M. bovis as etiological agents of tuberculous lymphadenitis (TBLN). Methods: Patients with lymphadenopathy (n = 171) were included in a cross-sectional study at Butajira Hospital; Southern Ethiopia. Lymph node biopsies were cultured. Patients' HIV status was identified. DNA from positive cultures was tested by PCR to identify M. bovis and M. tuberculosis. Isolates were genotyped by multiplex ligation-dependent probe amplification (MLPA) assay. Results: Among 171 patients; 156 had culture results. Of these; 107 (69) were positive for M. tuberculosis complex (MTC). Six of the 10 HIV-positive patients were culture positive. M. tuberculosis specific sequences were identified in the DNA of each of 100 samples as assessed by RD10 targeted PCR; and each of the 95 isolates exhibited the M. tuberculosis specific TbD1 deletion by MLPA analysis. No M. bovis was identified. These results indicate that all the isolates were modern M. tuberculosis strains. Furthermore; MLPA studies confirmed that 42of the isolates showed the Haarlem genotype and 12displayed sequences compatible with INH resistance. No mutations conferring resistance to ethambutol or rifampicin were detected. Conclusions: Our data showed that M. tuberculosis strains had common characteristics with strains causing pulmonary TB; which appears to be the main etiological agent of TBLN

Typhoid Fever in Ethiopia

This review focuses on the reports of salmonellosis by investigators in different parts of Ethiopia; in particular focusing on the levels of typhoid fever. Many of the reports are published in local journals that are not available online. There have been seven studies which diagnosed typhoid fever by laboratory culture and there is no coordinated epidemiological surveillance. All conducted research and reports from different health institutions in Ethiopia indicate that typhoid fever was still a common problem up to the most recent study in 2000 and that the extensive use of first-line drugs has led to the development of multiple drug resistance. In the sites covered by this review; the total number of published cases of typhoid fever dropped over time reflecting the decline in research capacity in the country. Data on the proportion of patients infected by different serovars of Salmonella suggest that the non-Typhi serovars of Salmonella are increasing. The published evidence suggests that typhoid fever is a current public health problem in Ethiopia although population based surveys; based on good microbiological diagnosis; are urgently needed. Only then can the true burden of enteric fever be estimated and the benefit of public health control measures; such as health education; safe water provision; improved food hygienic practices and eventually vaccination; be properly assessed