A 15-year-old, 6.8-kg, female Patas monkey (Erythrocebus patas patas) was evaluated for persistent weight loss, partial anorexia, and hypercalcemia (15 mg/dl; normal=9.297±0.689 mg/dl). Previous diagnostics, including complete blood count, serum chemistry panel, survey radiographs, and gastric endoscopy failed to identify an underlying cause. A computed tomography (CT) scan identified left renal calculi which were removed by shock-wave lithotripsy (Storz Modulith SLX-T lithotripsy unit, NextMed). A total of 1500 gaited shock waves were administered, gradually increasing the power at 50 shock intervals until a maximum level of “6” was attained at 300 shocks. Initial improvement in clinical signs was not sustained, and right renal densities were later identified on survey radiographs. Parathyroid hormone (PTH; 167.5–213.20 pmol/L) and ionized calcium values (1.69–1.91 mmol/L) were elevated compared to conspecifics (PTH=57.0–64.8 pmol/L; ionized calcium=1.27 mmol/L). A CT scan confirmed the presence of right renal calculi and cervical ultrasound identified a 6-mm mass in the left thyroid region. A partial left thyroidectomy was performed to remove an embedded mass, confirmed as a parathyroid adenoma on histology. The lithotripsy procedure was repeated for the right kidney, using the same technique as previously described. Serum calcium, ionized calcium, and parathyroid hormone were at expected values, and improved appetite and weight gain were observed 1 month post-surgery. The patient died 6 months later with histologic evidence of chronic interstitial nephritis, fibrosis, and tubular proteinosis with myocardial and valvular fibrosis.