Ureteral stones can cause flank pain and, if untreated, lead to serious renal complications. Bilateral obstruction may be overlooked, especially in vulnerable populations. We report a case of a 40-year-old foreign laborer with bilateral UPJ stone impaction, complicated by renal failure, acidosis, and anemia. This highlights the need for early detection and prompt treatment, even for small stones.

A 40-year-old male foreign laborer presented to the emergency department (ED) after experiencing bilateral flank pain for several weeks, which had become intolerable during his day off. Physical examination showed bilateral costovertebral angle tenderness. An initial ultrasound examination revealed severe hydronephrosis, and laboratory tests showed white blood cell (WBC) count 7710/ul (segmented neutrophils 77.8%), C-reactive protein (CRP) 2.64 mg/L, hemoglobin 6.8 g/dL, blood urea nitrogen (BUN) 117 mg/dL, creatinine 19.44 mg/dL, hyponatremia (sodium, Na=131 mmol/L), hypokalemia (potassium, K = 3.1 mmol/L), metabolic acidosis (pH 7.061, bicarbonate 5.5 mmol/L), and hypercalcemia (ionized calcium 1.89 mg/dL). Abdominal computed tomography confirmed bilateral hydronephrosis, grade IV, and bilateral ureteropelvic junctional stone impaction around 0.8-0.9 cm, with thin renal cortex (Figure 1-2). Urgent bilateral percutaneous nephrostomy (PCN) insertion was performed. Four days post-PCN insertion, follow-up laboratory results showed a decrease in creatinine levels to 11.96 mg/dL.

Bilateral ureteral stone impaction may cause severe renal damage, acidosis, and anemia. Even if pain is mild or stones are small, early intervention is crucial to prevent hydronephrosis and irreversible kidney injury.