Leptospirosis-Associated Acute Kidney Injury Presenting with Polyuria and Hypokalemia-Induced Flaccid Quadriparesis in a Young Farmer: A Case Report

Abstract

Leptospirosis is a globally distributed zoonotic infection that can cause acute kidney injury (AKI), electrolyte disturbances, and rare neuromuscular complications. Non-oliguric AKI accompanied by polyuria and hypokalemia represents an important but often underrecognized manifestation of leptospiral nephropathy. This case report aimed to describe the clinical presentation, diagnostic evaluation, management, and outcome of leptospirosis-associated AKI complicated by severe hypokalemia and flaccid quadriparesis. A 36-year-old male farmer was evaluated through clinical examination, serial laboratory assessments, serologic testing, urinalysis, electrocardiography, abdominal ultrasonography, urine output monitoring, and muscle strength evaluation. The patient developed marked polyuria of 7,000 mL/24 hours, severe hypokalemia with serum potassium levels decreasing to 2.3 mmol/L, azotemia, and acute flaccid quadriparesis characterized by grade 2 muscle strength and absent deep tendon reflexes. Leptospira IgM was positive, while ultrasonography findings suggested bilateral acute tubulointerstitial nephritis. The findings indicated that renal tubular dysfunction and potassium wasting were key mechanisms contributing to polyuria and neuromuscular impairment. Management included intravenous fluid therapy, controlled potassium and sodium replacement, ceftriaxone administration, and continuous electrolyte and electrocardiographic monitoring. Muscle strength gradually recovered to grade 5, serum potassium normalized to 3.6 mmol/L, urine output decreased, and renal function improved within six days. Early recognition and systematic correction of fluid and electrolyte disturbances can lead to complete recovery from this severe complication of leptospirosis.