Laboratory studies on the outbreak of Gangrenous Ergotism associated with consumption of contaminated barley in Arsi, Ethiopia

Abstract

Background: Ergotism is caused by the fungus Claviceps purpurea, which parasitizes cereal grains and is ingested by man through flour milled from contaminated cereals. An outbreak of ergotism in Ethiopia in 1978 resulted from exposure to ergot alkaloids from C. puruprea sclerotia. Objectives: The objective of this study was to investigate consumption of cereal grains grown locally as the most likely cause of the outbreak of gangrenous ergotism so that control measures could be applied. Methods: During June to August, 2001, there were reports of a large number of cases of gangrene in Arsi Zone, Ethiopia. A multi-disciplinary team assessed the outbreak of the decease. Non-structured in-depth interviews were conducted with heads of households of the affected, and each of the patients was also interviewed. Grain samples were then collected from the interviewed households and analyzed for ergot alkaloids. Acute toxicity studies were also conducted by feeding male, non-pregnant and pregnant Swiss albino mice with the collected grain samples. Results: Mycological cultures of grain samples yielded ergot alkaloids. All the grain samples contained ergot alkaloids, but with varying concentration. The highest concentration of ergotamine was observed in grain samples No. 4 (2.51 mg/100 g) and No. 6 (2.66 mg/100 g). Grain samples No. 2 and 7 had similar concentration of ergotamine, but more than four-fold higher than in grain sample No. 3. In contrast, the concentration of ergometrine in grain samples No. 4 (1.15mg/100 g) and No.6 (1.21mg/100 g) were two-fold lower than ergotamine. The highest death (55%) of mice was observed in those test groups fed on grain samples No. 4 and No. 6. Cases of abortion were noted after 3 days of feeding in all pregnant mice with the exception of those allocated to grain sample No. 3. Conclusion: We conclude on the basis of these results that the outbreak of gangrene in Arsi Zone, Ethiopia, is attributed to the ingestion of barley containing ergotized wild oats