Case 212. Bartonellosis (cat scratch disease) (40 y-o F)
Biopsied axillary lymph node, swollen 2 weeks after bite by a suckling cat
Key words : Bartonella henselae, suppurative granuloma
Epithelioid granulomas are randomly distributed in the enlarged lymph node (HE, low power). Most of the patients keep a kitten, and have a history of scratch or bite by the cat. The incidence is seasonally high in autumn through winter. Regarding the systemic infection, refer to case 47.   In the center of the granuloma, small abscess is formed (suppurative granuloma). Langhans-type giant cells are not prominent (HE). Similar suppurative granulomas are seen in tularemia, yersiniasis, lymphogranuloma venereum, melioidosis, Alkaligenes infection and listeriosis.
The causative agent of this infection is Bartonella henselae. Warthin-Starry's silver shows a few short rods in the central necrosis. However, this silver method has difficulty in reproducibility and needs skill. Usually, the diagnosis is based on the clinical history and histology of the node.