Cat scratch disease (CSD) is a benign disease characterized by fever, self-limited regional lymphadenitis, and skin lesions due to cat scratch or bite. CSD shows a worldwide distribution and has been mostly reported in children aged less than 18 yr of age. The etiologic agent of CSD is Bartonella henselae, a gram-negative rod [1]. Little is known about the epidemiology of CSD in Korea. Since B.henselae is fastidious and cannot be grown in cultures, only 2 CSD cases have been reported using molecular genetic methods in Korea [2,3]. Here, we present the third case of CSD in a Korean pediatric patient; the disease was confirmed using PCR and DNA sequencing with pri- 34We report a case of cat scratch disease in an 8-yr-old girl who presented with fever and enlargement of both axillary lymph nodes. Both aerobic and anaerobic cultures of the lymph node aspirate were negative for microbial growth. Gram staining and Warthin-Starry silver staining did not reveal any organism. Purified DNA from the PCR-amplicon of the 16S-23S rRNA intergenic region was sequenced and showed 99.7% identity with the corresponding sequence of Bartonella henselae strain Houston-1. Our findings suggest that the internal transcribed spacer is a reliable region for PCR identification of Bartonella species. In patients with lymphadenitis, a history of contact with cats or dogs necessitates the use of diagnostic approaches that employ not only the conventional staining and culture but also molecular methods to detect B. henselae. (Korean J Lab Med 2010;30:34-7)