Background: Cat scratch disease is a benign, self-limiting but rare condition that causes significant lymphadenopathy. There is less than 1 case per 100,000 cases per year, mostly in children. Even rarer are cases presenting in association with malignancies, usually non-Hodgkin lymphoma. Our review of the literature revealed only 1 case of cat scratch disease as-sociated with Hodgkin lymphoma. We describe here a case of a 43-year-old white man who presented with a clinical picture of recurrent Hodgkin lymphoma but with negative serology for Bartonella antibodies, responding to a short course of antibiotic treatment.
Methods: This 43-year-old patient initially presented with stage IA Hodgkin lymphoma in January 2011. He had a me-diastinal mass, which was resected and followed by 4 cycles of ABVD (doxorubicin, bleomycin, vincristine, dexameth-asone) chemotherapy. In July 2011, he went into complete remission after 4 cycles of chemotherapy and remained so until October 2014, when he noted increasing left-sided in-guinal adenopathy accompanied by a constant stabbing pain. He had no other symptoms. On positron emission tomogra-phy/computed tomography (PET/CT) scanning he had sev-eral hypermetabolic splenic lesions and enlarged tonsillar, retroperitoneal, pelvic, axillary, and inguinal lymph nodes. His complete blood count and chemistries were normal. His sedimentation rate was also normal. Bilateral bone marrow biopsies were negative for Hodgkin disease recurrence. Bi-opsy of one of his inguinal nodes was positive for necrotiz-ing granulomas and stained positive for CD2, CD3, and CD5 with areas of high Ki-67 proliferation. Hodgkin disease, how-ever, was not confirmed. He mentioned a family history of cat scratch disease a decade ago when his 2 young children were diagnosed with cat scratch disease and treated with oral antibiotics, resulting in complete resolution of symptoms. Se-rologic testing for Bartonella antibodies was ordered for him but came back negative. An infectious disease consult was re-quested, and he was treated empirically with a 5-day course of azithromycin.
Results: After 2 months, he was seen in the clinic and found to have no palpable inguinal adenopathy. A repeat PET/CT scan at 3 months showed resolution of all areas of lymphadenop-athy with the exception of the left inguinal node basin. At 5 months, all areas of hypermetabolic adenopathy had resolved. A repeat serology for Bartonella antibodies remained negative.
Conclusions: Cat scratch disease is extremely rare but can occur in a patient with known hematologic malignancies. In this case, it was mistaken as a recurrent case of relapsed Hodgkin disease but fortunately resolved quickly. The pre-sentation can be acute; patients can have negative serologies for Bartonellosis, yet achievement of a complete clinical and radiographic response with a short course of oral antibiotics was successful.