Renal Microabscesses: A Presentation of Cat Scratch Disease

A previously healthy 5-year-old girl was referred following a spiking fever for 8 days accompanied by abdominal pain, fatigue, and headache. Physical examination was unremarkable. Initial laboratory evaluation revealed a white blood cell count of 12 100/mm (normal ranges, 4000-10 000/mm3) and C-reactive protein of 12.06 mg/dL (normal value, < 0.8 mg/dL). Urinalysis showed 33 white cells/high-power field. Liver and renal functions were within normal limits. Empiric antibiotics were given but spiking fever persisted. Bacterial and fungal cultures of blood, urine, and bone marrow yielded no growth. Contrast-enhanced computerized tomography revealed multiple small hypodense lesions scattered throughout the cortex of both kidneys consistent with microabscesses (Figure 1). In addition, multiple enlarged lymph nodes were found at mesenteric root and para-aortic regions (Figure 2; available at www.jpeds.com). No abnormalities of the liver and spleen were seen. All studies for fever of unknown origin were negative. However, a careful history revealed she had close contact with kittens at home and that she had been scratched by a cat. Indirect immunofluorescence antibodies for Bartonella henselae were positive for Immunoglobulin G (1: 2048) and Immunoglobulin M (1: 320). Therefore, renal cat scratch disease (CSD) was diagnosed. The fever gradually subsided during 4 weeks of tetracycline and