Mycetoma due to Nocardia caviae.

Mycetoma is the most frequent deep mycosis in Mexico and is caused by Nocardia brasiliensis in 86% of the cases. Two cases of mycetoma due to Nocardia caviae, the first in Mexico, are reported. The strains were identified by their biochemical properties according to the criteria of Gordon and Mihm (1962). Few cases of mycetoma caused by this actinomycete have been reported in the world. One of our cases was unusual: occurring on the trunk as a tumor and diagnosed by finding the "grains" on histologic examination.