12268 Hypercalcemia Alert: Exploring The Link To Isolated Bone Marrow Sarcoidosis

Abstract Disclosure: M. Renzu: None. C.M. Hubers: None. V. mehta: None. A. Qazi: None. D.K. Yerasuri: None. Introduction: Sarcoidosis, a complex disorder marked by granuloma formation in diverse organs, often affects the lungs, but can involve various systems as well. Rare cases of bone marrow involvement may mimic conditions like multiple myeloma, emphasizing the need to consider sarcoidosis in patients with bone marrow abnormalities, especially those without typical myeloma features. Case Presentation: A 79-year-old white male with a medical history of hypertension, hyperlipidemia, deep venous thrombosis, prostate cancer in remission, chronic knee pain, and basal cell carcinoma presented for pre-operative evaluation, as he was scheduled for an elective orthopedic procedure. On routine lab work, he was found to have acute hypercalcemia and normocytic anemia. This finding raised suspicion for an underlying systemic pathology. He reported that he did not take any calcium or vitamin D supplements at home. Subsequent endocrine assessment, including evaluation of parathyroid hormone and vitamin D levels, revealed a non-PTH-mediated hypercalcemia. The persistence of hypercalcemia prompted further investigations, including assessments for multiple myeloma by oncology. The workup was negative for multiple myeloma but significant for granulomas on bone marrow biopsy, a finding consistent with sarcoidosis. Additionally, angiotensin converting enzyme levels were elevated at the time of diagnosis. Interventions led to the resolution of hypercalcemia following steroid therapy of prednisone 20 mg daily and close follow up with endocrinology. As part of his follow up, ACE levels are being regularly monitored, with the patient going for lab work every other month. Discussion: Bone marrow biopsies rarely reveal granulomas and sarcoidosis accounts for only a very small percentage of these findings. The standard workup for sarcoidosis typically does not include bone marrow biopsies. By integrating biopsies into the standard diagnostic protocol researchers may gain insights into the etiology and mechanisms driving this manifestation of sarcoidosis, ultimately improving diagnostic accuracy and patient care. Distinguishing sarcoidosis from multiple myeloma also poses diagnostic challenges, necessitating thorough evaluation in patients with bone marrow abnormalities. Despite its rarity, clinical suspicion for sarcoidosis should be considered in patients with underlying hematologic disorders or malignancies. Additionally, sarcoidosis exhibits geographical variation, being less common in Japanese men and more prevalent in African American women. This highlights the importance of considering demographic factors when evaluating patients for sarcoidosis and its extrapulmonary manifestations. Long-term outcomes in isolated bone marrow sarcoidosis remain unclear, warranting surveillance for progression to multiple myeloma or other lymphoproliferative disorders. Presentation: 6/2/2024