Persistent cat scratch disease requiring surgical excision in a patient with MPGN.

We present the case of a 13-year-old immunosuppressed patient with unrelenting cat scratch disease despite 9 months of antibiotic therapy. The patient was being treated with mycophenolate and prednisone for membranoproliferative glomerulonephritis (type 1) diagnosed 13 months before the onset of cat scratch disease. Cat scratch disease was suspected due to epitrochlear lymphadenitis and an inoculation papule on the ipsilateral thumb, and the diagnosis was confirmed by the use of acute and convalescent titers positive for Bartonella henselae. The patient experienced prolonged lymphadenitis despite azithromycin and rifampin therapy, and she developed a draining sinus tract ∼4 months after initial inoculation while receiving antibiotics. Acute exacerbation of the primary supratrochlear node prompted incision and drainage of the area, with no improvement in the disease course. Ultimately, excision of all affected nodes and the sinus tract 9 months after the initial diagnosis was required to achieve resolution. Bartonella was detected at a high level according to a polymerase chain reaction assay in the excised nodes. Persistent treatment with oral antibiotics may have prevented disseminated infection in this immunosuppressed patient. Surgical excision of affected nodes should be considered in patients with cat scratch disease that persists beyond 16 weeks.