Syndrome of Rochalimaea henselae adenitis suggesting cat scratch disease.

To describe a clinical syndrome of cat scratch disease caused by Rochalimaea henselae, including methods for isolation of the organism from tissue and for identification. Case series. U.S. Air Force referral hospital infectious diseases clinic. Two previously healthy patients. Two immunocompetent patients who had handled cats developed unilateral upper-extremity adenitis associated with a distal papular lesion and fever. The adenitis and distal lesions persisted and progressively worsened. Cultures of the involved lymph nodes from both patients grew R. henselae, a recently described organism associated with bacillary angiomatosis and peliosis hepatis in human immunodeficiency virus-infected patients and with bacteremia in immunocompromised and immunocompetent hosts. The organism was characterized as oxidase negative and X-factor dependent and had a characteristic pattern in analysis of whole-cell fatty acids differing from Afipia felis, a bacterium that has been associated with cat scratch disease. The identity of the isolate was confirmed by analysis of whole-cell fatty acids using gas chromatography and by amplification of the citrate synthetase gene sequence and analysis of the polymerase chain reaction-amplified product. The organisms were broadly susceptible to a variety of antimicrobials by broth microdilution; however in-vitro resistance to first-generation cephalosporins correlated with clinical failure of therapy. Rochalimaea henselae can be a cause of cat scratch disease in immunocompetent patients.