Severe hypercalcemia unmasked by Vitamin D in a patient with sarcoidosis
A 53-year-old lady, detected to be diabetic and hypertensive for 7 years presented with h/o generalized weakness, poor appetite, and constipation of 1 month. She had lost about 1-2 kgs in the preceeding month. There was no h/o fever, night sweats, proximal or distal muscle weakness, arthralgia, or rash. She was post-menopausal and had undergone total abdominal hysterectomy for dysfunctional uterine bleeding 8 years earlier. She denied any respiratory symptoms. Her medications included insulin, glimeperide, atenolol, and multivitamin. She had received two injections of Vitamin D 60,000 International Units (IU) 1 week apart for about a month before presentation elsewhere for suspected osteomalacia. On examination, she was thin built, had a blood pressure of 130/90 m of Hg, pulse rate of 86/min, and respiratory rate of 18/min. General physical examination was non-contributory and no peripheral lymphadenopathy could be appreciated. Systemic examination of the cardiac, respiratory, and abdominal evaluations was normal. Her investigations are summarized in . A thorough work-up was done to investigate the cause of hypercalcemia.\nUltrasound examination of the neck did not reveal any thyroid or parathyroid nodule. Serum electrophoresis was normal and mammogram was negative. Computed tomography abdomen was negative and did not show any lymphadenopathy. High resolution computerized tomography chest revealed reticulonodular shadows in both lung fields, one small paratracheal lymph node and two isolated pleural nodules. With clinical suspicion of sarcoidosis with associated renal failure, a renal biopsy was done and this revealed non-caseating granulomatous interstitial nephritis with features of acute tubular injury []. Patchy chronic interstitial nephritis was also noted. She was initially treated before the biopsy diagnosis with intravenous hydration, furosemide to increase renal calcium excretion, and one dose of calcitonin. A temporary reduction in serum calcium was noted to 13.4 mg/dL. Following the diagnosis of sarcoidosis, she was then started on betamethasone followed by oral prednisone at 1 mg/kg for 1 week, tapered to 0.5 mg/kg at discharge. This led to a gradual fall in calcium levels and some improvement in renal functions. Serum creatinine at last follow-up was stable at 1.5 mg/dL.