Case ReportsKidney Actinomycosis, A Rare Diagnosis That Can Mimic Renal Cell Carcinoma A Case Report and Review of the LiteratureManasanch, Elisabet Esteve MD*; Grivas, Petros D. MD, PhD†; Walter, Otto MD‡; Davaro, Raul MD§Author Information From the *Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD; †Division of Hematology and Oncology, Department of Internal Medicine, School of Medicine, University of Michigan, Ann Arbor, MI; ‡Department of Pathology, and §Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Massachusetts, Worcester, MA. Correspondence to: Elisabet Esteve Manasanch, MD, National Institutes of Health, 9000 Rockville Pike, Bldg 10, 12N226, Bethesda, MD 20892. E-mail: [email protected]. The authors have no funding or conflicts of interest to disclose. Infectious Diseases in Clinical Practice: September 2012 - Volume 20 - Issue 5 - p 362-364 doi: 10.1097/IPC.0b013e31824f8c34 Buy Metrics Abstract Actinomycosis of the kidney is a rare bacterial infection, which poses a diagnostic challenge. Because the diagnosis can mimic a renal tumor, excision is often the diagnostic and therapeutic option. We describe the first case of renal actinomycosis in a woman with previously diagnosed renal cell carcinoma of the contralateral kidney. In contrast to most cases, sparing of her only functioning kidney was the priority that prompted a conservative diagnostic approach and treatment, as equally effective as surgery. © 2012 Lippincott Williams & Wilkins, Inc.