Snake envenomation-induced acute interstitial nephritis

Background and Objectives: Acute kidney injury (AKI) is one of the major complications of snake envenomation, especially in the developing countries. The most common renal histology in snakebite-induced AKI is acute tubular injury (ATI), but acute interstitial nephritis (AIN) is rarely reported. Materials and Methods: We did a prospective observational study between January 2012 and May 2017 to analyze the demographic, clinical, and laboratory data, response to treatment, and outcome of patients with snakebite-induced AIN. Results: About twenty patients were included in the study with mean follow-up of 24 ± 6 months. Of them, 6 (30%) were males. Mean age was 50.9 ± 22.1 years. All the patients received anti-snake venom. AKI developed after a mean duration of 24.1 ± 11.2 h and 15 patients were oliguric. Cellulitis was seen in 65% of patients, anemia in 65%, leukocytosis and thrombocytopenia in 40%, and coagulopathy in 80%. Mean peak serum creatinine was 7.8 ± 3.2 mg/dL. Peripheral eosinophilia was seen in 7 (35%) patients. All the patients were managed with hemodialysis and all except one received oral steroids. Six patients (30%) progressed to chronic kidney disease (CKD) with mean follow-up creatinine of 1.49 ± 0.8 mg/dL. Conclusion: It is prudent to do renal biopsy in patients with snakebite-induced AKI when there is a suspicion of pathology other than ATI. Identification and treatment of AIN with steroid will avoid progression to CKD which has an impact on growing health burden in tropical countries.