[Two cases of suspected Bartonella henselae infection from a dog]

A 55-year-old male was admitted to our hospital because of fever and left submaxillary, right axillary, and left inguinal lymphadenopathy. A presumptive diagnosis of rickettsiosis was made and treatment with oral doxycycline was started. Lymphadenopathy was partialy resolved after antibiotics treatment. Ablation of the left inguinal node was done and histopathological examination showed non-Hodgkin's lymphoma. Lymphadenopathy was resolved by chemotherapy. The second patient, a 40-year-old male, developed a tender submandibular node. Excisional biopsy of the node was performed to eliminate lymphoma. Histopathological examination revealed granulomatous lymphadenitis with follicular hyperplasia. The patients had no history of cat contact, but owned a dog. Diagnosis of both cases was confirmed by the detection of IgG antibodies to Bartonella henselae with an enzyme immunoassay. Our findings suggest that dogs are implicated in B. henselae infection and can serve as a reservoir of the organism as well as cats. In the abscence of other bacterial and especially after exposure to dogs, B. henselae should be included as possible cause of lymphadenopathy.