Abstract
BACKGROUND AND OBJECTIVES: The objective of this study was to describe the characteristics of patients with HIV infection and biopsy-proven acute interstitial nephritis (AIN). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Pathology reports were reviewed for patients who had HIV infection and underwent renal biopsy at Johns Hopkins Hospital from January 1, 1995, through January 1, 2008. Patients who received a diagnosis of AIN without evidence of HIV-associated nephropathy were identified, and their clinical course was reviewed up to 18 months after biopsy. RESULTS: Of 262 biopsies, 29 (11%) patients who had AIN without evidence of HIV-associated nephropathy were identified. The mean age at the time of biopsy was 47.5 years (range 28 to 71 years), 17 (59%) were men, and 23 (79%) were black. The majority (62%) of patients were on antiretroviral therapy, 59% were current or former intravenous drug users, and 62% had hepatitis C co-infection. Drugs were identified as the cause of AIN in the majority (72%) of cases. Nonsteroidal anti-inflammatory drugs were most commonly implicated, followed by sulfamethoxazole/trimethoprim. Antiretroviral therapy was identified as the cause in only three cases. None of the patients presented with the classic triad of fever, rash, and pyuria, and only seven (24%) patients presented with <1 g/d proteinuria. CONCLUSIONS: In our series, AIN was prevalent (11%) and was often drug induced. AIN should not be excluded from the differential diagnosis on the basis of absence of the classic clinical triad of fever, rash, and pyuria.