UNCOMPLICATED CAT-SCRATCH DISEASE - FINDINGS AT CT, MR-IMAGING, AND RADIOGRAPHY

PURPOSE: To describe the epidemiologic, clinical, and imaging features of cat-scratch disease (CSD) to facilitate prompt recognition and non invasive diagnosis of this condition. MATERIALS AND METHODS: Eight oth erwise healthy patients with pet cats presented with the subacute onse t of epitrochlear, axillary, or groin masses. All underwent cross-sect ional imaging with computed tomography (CT) (n = 1) or magnetic resona nce (MR) imaging (n = 7). Five patients underwent radiography of the e lbow. RESULTS: In all patients, MR imaging and CT showed a poorly defi ned soft-tissue mass with extensive surrounding edema in an efferent l ymphatic distribution. Radiography revealed only soft-tissue edema in two patients and an ill-defined soft-tissue mass with soft-tissue edem a in three patients. Six patients underwent biopsy; the findings of al l pathologic specimens supported the diagnosis of CSD. No patients und erwent serologic evaluation. All patients were asymptomatic within 4 w eeks of beginning antibiotic therapy. CONCLUSION: CSD should be consid ered in all patients with upper extremity or head and neck adenopathy and a history of cat exposure. Although generally not required for dia gnosis, cross-sectional imaging will reveal a mass with surrounding ed ema in an area of lymphatic drainage.