C40-06 Atypical Presentation of Pulmonary Sarcoidosis as Severe Symptomatic Hypercalcemia

Abstract Sarcoidosis is a multisystem granulomatous disease that commonly affects the lungs and intrathoracic lymph nodes. Most patients are asymptomatic or present with respiratory symptoms. Though it is associated with hypercalcemia, rarely does sarcoidosis present with severe symptomatic hypercalcemia. A 63-year-old female with a history of asthma and atopic dermatitis presented to the hospital with three weeks of fatigue, poor appetite, nausea, constipation, and an unintentional 10-pound weight loss. Initial labs were notable for hypercalcemia of 14.5 mg/dL, and low 25-OH Vitamin D and parathyroid hormone levels of 21 ng/ml and 10 pg/ml respectively. She had an acute kidney injury, with blood urea nitrogen and creatinine of 23mg/dL and 1.86mg/dL respectively, increased from baseline creatinine of 1.19 mg/dL. 1-25 OH Vitamin D was elevated at 95 pg/ml. CT Thorax showed scattered bilateral pulmonary nodules measuring 5 to 7 millimeters concerning for metastases, mediastinal and hilar lymphadenopathy, and bilateral pleural effusions. She was initiated on intravenous fluids, calcitonin, and zoledronate which improved her symptoms, serum calcium, and renal function. She underwent endobronchial ultrasound with endobronchial biopsy of stations 7 and 4R. Histology showed non-caseating granulomas consistent with sarcoidosis. Though corticosteroids were deferred by pulmonology due to normal spirometry and minimal respiratory symptoms, they were initiated by endocrinology for sarcoidosis-related hypercalcemia. Pulmonary sarcoidosis classically manifests as hilar and mediastinal lymphadenopathy on imaging. Hypercalcemia is often associated with sarcoidosis, a granulomatous disease, because macrophages express high levels of 1-alpha hydroxylase which increases serum calcitriol and calcium absorption. However, hypercalcemia is actually quite rare in sarcoidosis, seen in approximately 3 - 12% of cases. Of this subset, most are asymptomatic, and the hypercalcemia is an incidental laboratory finding; rarely is it severe or symptomatic hypercalcemia as in this case. Additionally, the imaging findings for this patient are inconsistent with classical pulmonary sarcoidosis. If there is parenchymal involvement in sarcoidosis, typically it presents as innumerable micronodules (less than 5 millimeters) that follow a perilymphatic distribution and concentrate in the fissures or bronchovascular bundles. In this case, the patient had much larger nodules that were randomly distributed, along with pleural effusions. Given the severe hypercalcemia and larger pulmonary nodules, malignancy was higher on the differential, and it was noteworthy when the final pathology was instead consistent with sarcoidosis. This case highlights an atypical presentation of pulmonary sarcoidosis, both from initial symptom and laboratory presentation with severe hypercalcemia, as well as imaging findings not typically seen in sarcoidosis. This abstract is funded by: None