(10.16) Unusual Presentation of Hypercalcemia in Granulomatous Disease

Hypercalcemia can be seen in most granulomatous disease such as sarcoidosis and tuberculosis. Mycobacterium avium-complex (MAC) is an infectious granulomatous disease which is associated with hypercalcemia especially in immunocompromised patients and rarely can occur in immunocompetent patient. We report a case of hypercalcemia with multiple lymphadenopathy with biopsy confirmed of non-necrotizing granuloma likely secondary to MAC in an immunocompetent individual.

Case(s) Description :

A 51 year-old-male with medical history of hypertension was initially referred to endocrinology clinic for evaluation of hypercalcemia. Patient noticed weight loss (56 pounds over the 2 years), night sweats, intermitted fevers, constipation and fatigue. Outpatient work up revealed corrected calcium 13.0md/dL, 1,25-dihydroxyvitamin D (calcitriol) 104pg/dL, 25-hydroxyvitamin D 16.8ng/dL, hemoglobin was 12g/dL, creatinine 2.1mg/dL, intact Parathyroid hormone (iPTH) 10pg/dL, PTH related Protein < 2pmol/L, serum protein electrophoresis showed biclonal M spike less than 0.5g/dL, urine protein electrophoresis negative. Bone marrow biopsy did not show any evidence of multiple myeloma and lymphoma. PET/MRI of the whole body showed multiple hypermetabolic lymph nodes in the neck, chest, abdomen, pelvis, groin and popliteal regions. Patient was hospitalized and received hypercalcemia treatment including prednisone 40mg daily. CT chest, abdomen and pelvis showed multiple lymphadenopathy with some calcifications largest on right inguinal lymph node. All the infectious work up was negative. CT guided core needle biopsy of right inguinal lymph node showed non-necrotizing granulomatous inflammation; negative for acid-fast bacilli (AFB). Patient clinically improved and discharged. One set of AFB sputum culture revealed Mycobacterium chimaera/intercellulare group isolated identified by mass spectrometry analysis. However, unable to perform confirmatory testing since patient lost follow up.  

Discussion :

We present a patient with hypercalcemia and multiple lymphadenopathy presumed secondary to non-necrotizing granulomatous disease. One-set of AFB cultures revealed M. chimaera/intercellulare. The rare association with MAC-associated hypercalcemia has been described extensively in HIV, lymphoma, and other immunocompromised patients, but it is a rare phenomenon in immunocompetent patients. MAC cultures are not part of the routine microbiological workup. Repeat sputum culture will confirm the diagnosis. Granulomatous diseases like MAC can cause hypercalcemia via activation of macrophages which express extrarenal 1-alpha-hydroxylase. Glucocorticoids are an effective treatment for MAC-associated hypercalcemia.