Nocardia caviae: a report of 13 new isolations with clinical correlation

Thirteen isolates of Nocardia caviae from 12 different clinical sources were received and identified over a 5(1/2)-year period by the Mycology Division of the Center for Disease Control. The results of morphological, biochemical, and physiological studies on these isolates were compared with those obtained with four reference cultures of N. caviae received from the Institute of Microbiology, Rutgers University. Comparison showed that N. caviae isolates form a homogeneous group that is usually easily distinguished from N. asteroides, N. brasiliensis, and other pathogenic aerobic actinomycetes. The clinical sources included nine human and two animal infections and one human isolate apparently not associated with disease. Previous reports of N. caviae infections in man have been limited to rare cases of actinomycotic mycetoma. Among the human infections reported in this series are one case of mycetoma, one case of "mycotic" keratitis, one case of skin abscess, two cases of osteomyelitis, and four cases of serious pulmonary infection caused by N. caviae.