When Parasites Attack the Kidneys: A Case of Severe AKI from Ascaris lumbricoides-Induced Acute Interstitial Nephritis

Introduction: Ascaris lumbricoides infection is common in endemic areas but rarely associated with renal disease. However, helminth-induced acute interstitial nephritis (AIN) is an underrecognized cause of acute kidney injury (AKI), particularly in patients with eosinophilia and unexplained renal dysfunction. We report a case of severe AKI linked to A. lumbricoides, with favorable outcome following timely antiparasitic and corticosteroid therapy. Case Description: A 48-year-old woman with no medical history presented with intermittent low-grade fevers, generalized pruritus, and abdominal discomfort. She denied gastrointestinal symptoms or medication use. Lab results showed elevated creatinine (4.0 mg/dL), and blood urea nitrogen (85 mg/dL), eosinophilia (absolute number of eosinophils 2500/µL; 25.4%).Urinalysis revealed leukocyturia, microscopic hematuria, eosinophiluria and mild proteinuria(<1g/day). Renal ultrasound showed normal-sized kidneys with mildly increased cortical echogenicity and no obstruction or arterial stenosis. Autoimmune and infectious screens were negative. Stool analysis revealed A. lumbricoides ova, suggesting parasitic AIN. Renal biopsy was not performed due to thrombocytopenia (31,000/µL). The patient received a single 400 mg dose of albendazole and prednisone 1 mg/kg/day for two weeks, tapered over six weeks. Renal function improved progressively, with normalization of creatinine and resolution of eosinophilia and symptoms. Discussion: This case highlights parasitic AIN as a rare but reversible cause of AKI. The presence of eosinophilia, eosinophiluria, and AKI should prompt consideration of helminthic infection, especially in endemic areas. Similar reports have shown that prompt treatment with anthelmintics and corticosteroids can lead to recovery even without histological confirmation. Clinicians should include parasitic causes in the differential diagnosis of unexplained AKI. Early recognition and dual therapy can result in full renal recovery and prevent progression to chronic kidney disease.