Endocrine Abstracts

Introduction: The association of multiple myeloma (MM) with primary hyperparathyroidism (pHPT) is very infrequent. In addition pHPT may be overlooked or later diagnosed, because on the one hand certain clinical and laboratory characteristics of MM, such as hypercalcaemia, asthenia, osteoporosis and impaired renal function overlap with the elements of pHPT, on the other hand modern pHPT include non-classical (e.g. normocalcemic or mild clinical) forms. We present the case of a 75-years-old female (P.E.) known with operated recurrent kidney stones (1976, 1997, 2001), multiple fractures (both forearms 2001, clavicle 2004), and hypertension, chronic ischemic heart disease, heart failure NYHA III. In 2006 MM was diagnosed and specific haematological treatment (among others corticosteroids) was applied. In 2008 osteoporosis was discovered and clodronate (800 mg/day) therapy was started. Intermittent hypercalcaemia associated with lumbar pain, asthenia and dizziness were considered related to the hematological disease. In August 2011 arose the suspicion of primary hyperparathyroidism: iPTH: 540.4 pg/ml (normal:15–68.3), se-phosphate (se-P): 0.72 mmol/l (n:0.87–1.45), se-Ca: 2.28 mmol/l (n:2.15–2.57), Tc-99 m sestamibi scintigraphy suggested diffuse hyperplasia of both superior parathyroid glands. DXA osteodensitometry showed persistent osteoporosis (−2.49SD lumbar and −3.2SD femoral neck T-score). In October 2011 high total se-Ca-level was measured (12.45 mg/dl, n:9–11) with iPTH:283 pg/ml (n:8.7–79.6), creatinine-clearance: 66.1 ml/min, 25-OH-vitaminD:11 ng/ml (n>30), associated with aggravated asthenia. We increased the dose of clodronate to 1.200 g/day, and 40 mg po furosemide was given three times weekly. Within 2 weeks total se-Ca decreased to 11.18 mg/dl, albumine corrected se-Ca:10.74 mg/dl, but iPTH:407.6 pg/ml, so furosemide was reduced to 1 tablet/week. Low-dose calcitriol (0.50 μg/day) was carrefully introduced, taking into account vitamin D deficiency, osteoporosis and reduced kidney function in an aging person. Medical therapy was recommended instead of surgery: cinacalcet in association with bisphosphonate and calcitriol, with monthly control of calcaemia.

Conclusion: A very rare association between two infrequent diseases but with certain clinical/laboratory similarities, as well as the outcome under medical treatment is presented.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.