RESUMEN
OBJECTIVES: Information on antimicrobial susceptibility of bacterial pathogens is scarce in resource-poor settings. We determined the susceptibility of bacterial enteric pathogens and faecal Escherichia coli isolates obtained from children in urban Tamale, Northern Ghana, to antibiotics widely used in the that area [ampicillin or amoxicillin, trimethoprim/sulfamethoxazole (SXT) and chloramphenicol] and to alternative drugs. METHODS: Five Shigella spp., 6 Salmonella spp. and 318 E. coli were isolated from stool specimens obtained from 367 children with or without acute diarrhoea. Isolates were differentiated using standard laboratory procedures and tested using a breakpoint microbroth dilution method for their susceptibility to 18 antimicrobials and by disc diffusion for their susceptibility to chloramphenicol. RESULTS: Although the salmonellae showed an acceptable resistance pattern, E. coli isolates and the closely related shigellae were highly resistant. About 91% and 81% of E. coli isolates from patients or controls, respectively, were resistant to ampicillin (MICs > or = 8 mg/L), 88% and 76% to trimethoprim/sulfamethoxazole (MICs > or = 80/4 mg/L) and 46% and 41% to chloramphenicol (inhibition zones < or = 12 mm). Resistance to beta-lactam antibiotics or chloramphenicol was observed more frequently among isolates obtained from infants when compared with older children (1-4 years of age). CONCLUSIONS: Enteric bacteria from children in urban Northern Ghana are highly resistant to antibiotics used in that area. Therefore, new antibiotics should be introduced for the treatment of infections caused by these bacteria. Additionally, the establishment of a surveillance of the prevalence of the main bacterial infectious agents and their antimicrobial resistance is desirable.
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Infecciones por Enterobacteriaceae/microbiología , Enterobacteriaceae/efectos de los fármacos , Adulto , Niño , Preescolar , Diarrea/microbiología , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Heces/microbiología , Ghana , Humanos , Lactante , Recién Nacido , Pruebas de Sensibilidad Microbiana , Salmonella/efectos de los fármacos , Salmonella/aislamiento & purificación , Shigella/efectos de los fármacos , Shigella/aislamiento & purificaciónRESUMEN
BACKGROUND: Acute diarrhoea is a major cause of childhood morbidity and mortality in sub-Saharan Africa. Its microbiological causes and clinico-epidemiological aspects were examined during the dry season 2005/6 in Tamale, urban northern Ghana. METHODS: Stool specimens of 243 children with acute diarrhoea and of 124 control children were collected. Patients were clinically examined, and malaria and anaemia were assessed. Rota-, astro-, noro- and adenoviruses were identified by (RT-) PCR assays. Intestinal parasites were diagnosed by microscopy, stool antigen assays and PCR, and bacteria by culturing methods. RESULTS: Watery stools, fever, weakness, and sunken eyes were the most common symptoms in patients (mean age, 10 months). Malaria occurred in 15% and anaemia in 91%; underweight (22%) and wasting (19%) were frequent. Intestinal micro-organisms were isolated from 77% of patients and 53% of controls (P < 0.0001). The most common pathogens in patients were rotavirus (55%), adenovirus (28%) and norovirus (10%); intestinal parasites (5%) and bacteria (5%) were rare. Rotavirus was the only pathogen found significantly more frequently in patients than in controls (odds ratio 7.7; 95%CI, 4.2-14.2), and was associated with young age, fever and watery stools. Patients without an identified cause of diarrhoea more frequently had symptomatic malaria (25%) than those with diagnosed intestinal pathogens (12%, P = 0.02). CONCLUSION: Rotavirus-infection is the predominant cause of acute childhood diarrhoea in urban northern Ghana. The abundance of putative enteropathogens among controls may indicate prolonged excretion or limited pathogenicity. In this population with a high burden of diarrhoeal and other diseases, sanitation, health education, and rotavirus-vaccination can be expected to have substantial impact on childhood morbidity.