[Cat scratch disease showing clinical picture resembling tuberculous lymphadenitis: a case report]

On February 18th, 1997, a 61-year-old woman visited our hospital because of a left inguinal mass. On physical examination, the mass was soft without inflammatory sign. About one month later, the node was excised. Pathological examination revealed granulomas with caseous necrosis and Langhans giant cells, suggesting tuberculosis, although acid fast stain was negative. Thereafter, re-history taking in detail disclosed that a kitten had often scratched her. We reexamined the pathology and checked her for serum antibodies to Bartonella henselae, the etiological microbe of cat scratch disease (CSD), using enzyme immunoassay. Histopathological reexamination of the excised mass revealed suppurative granulomas in addition to caseous ones. The level of IgG (negative: < 12 units) to B. henselae was 78 units on March 25th, 138 units on April 19th, and 18 units on July 18th, while the level of IgM (negative: < 12 units) was negative at each determination. These serological results strongly suggested current infection of B. henselae. The diagnosis of CSD could be established based on the history and the laboratory findings. When one encounters a case of granulomatous lymphadenitis, CSD should be considered for the differential diagnosis, and in this regard, anamnesis about contact with cats should be asked.