Treatment of actinomycetoma due to Nocardia spp. with amoxicillin-clavulanate.

BACKGROUND: Actinomycetoma is a chronic occupational condition that occurs frequently in tropical regions. In Mexico 85% of cases are caused by Nocardia brasiliensis. There are two treatments of choice for these cases: a regimen of dapsone plus trimethoprim-sulfamethoxazole (co-trimoxazole) and, recently, amikacin, either alone or combined. However, not all cases respond properly to these therapies. OBJECTIVES: To report a retrospective, 11-year study of cases of actinomycetomas caused by Nocardia spp., treated with amoxicillin-clavulanate (co-amoxiclav). METHODS: All cases were identified clinically and microbiologically and had previously failed standard therapies. Oral co-amoxiclav 875/125 mg was administered every 12 h. Clinical, microbiological and laboratory follow up was performed every 2 months during the treatment period. RESULTS: Twenty-one cases of actinomycetoma were included, 19 caused by N. brasiliensis and one each by N. asteroides and N. otitidiscaviarum. Clinical and microbiological cure occurred in 15 of 21 cases (71%); two cases improved (10%) and four failed (19%). Mean treatment period was 9.6 months, during which neither side-effects nor laboratory test alterations were reported. CONCLUSIONS: Treatment with co-amoxiclav represents an alternative or rescue treatment for cases that have previously failed standard therapies.