P0573CLINICAL PRESENTATION AND OUTCOMES OF ACUTE INTERSTITIAL NEPHRITIS: A TEN YEARS' EXPERIENCE FROM A TERTIARY CARE HOSPITAL IN KARACHI, PAKISTAN

Abstract

Abstract Background and Aims Acute interstitial nephritis (AIN) is a potentially reversible, but relatively under-diagnosed cause of acute kidney injury. The effectiveness of steroids for treatment of AIN is debated. Data is scarce regarding the clinical presentation, use of steroids and its impacts on outcomes in AIN in our part of the world. The objective of our study was to study the clinical features, causes and outcomes of AIN and to evaluate the role of steroids in the management. Method We performed a retrospective study of 48 patients with biopsy proven AIN. Exposure was defined as the use of steroids. The main outcomes were recovery of renal function (Early (≤3 weeks) or Late (>3 weeks)) and hemodialysis dependence at 12 weeks Results 48 (4.9%) AIN cases were found among 978 renal biopsies performed from 2007-2018. Mean age was 47.6 ± 12.1 years. 56.3% were males. The offending agent was identified in 45.8% cases with NSAIDs (45.4%) being the most common, followed by antibiotics (22.7%), diuretics (9%), and PPI (4.5%). 75% presented with eGFR <15 ml/min/1.73m2 (n=36) out of which 58.3 % (n=21) needed hemodialysis. Mean proteinuria was 2.28 ± 0.99 g/day. 81.3% (n=39) patients received steroids out of which 39.6% were started on steroids after an initial period of observation after stopping the offending agent. Mean dose of prednisone was 0.8 ± 0.2 mg/kg per day. Mean time to steroid commencement was 14 ± 17.39 days. Early use of steroids (≤11 days after presentation) was significantly associated with earlier recovery (p= 0.009) as compared to late steroids (>11 days). A non-significant trend towards complete recovery (within 25% of baseline Creatinine) was noted in early steroid group (52.9%, n=17) vs “no steroid” (33.3%, n=9) or “late steroids” (10.5%, n=19) groups (p=0.208). 47.4% remained dialysis dependent on follow up with no difference made by steroid use (p=0.971). Conclusion Our data showed the benefit of earlier use of steroids in achieving rapid and complete renal recovery. Late steroid use was not associated with any further recovery of renal function at an additional risk of exposing patients to undue adverse effects. This is the first report from Pakistan documenting the tendency of nephrologists towards use of steroids for AIN.