Endocrine Abstracts

Abstract: Familial benign hypocalciuric hypercalcemia (FHH) is a rare AD disorder exhibiting benign hypercalcemia, inappropriately normal PTH levels and relative hypocalciuria, thus reflecting partial resistance to the normal effects of extracellular calcium on parathyroid glands and kidneys. We report a 74-year-old women, with no fracture history, with bisphosphonate osteoporosis treatment (2011-present), with HLA B 27 positive ankylosing spondylitis. The clinical exam revealed chronic joint pain, inflammatory lumbar pain, low spinal mobility, dorsal kyphosis and positive sacroiliac joint maneuvers. Calcemia levels were between 10.2-11.2 mg/dl, with normal PTH level after compensating the vitamin D deficiency. Urinary calcium/creatinine ratio was 0.0016 mg/dl and 24 h urinary calcium was 0.93 mg/kg per day. Parathyroid ultrasound was normal. Densitometry showed a good response to bisphosphonates with most recent lumbar BMD=0.701 g/cm², a T-score=−2.4 S.D. and left total hip BMD=1.189 g/cm², a T-score=−0.3 S.D. Her son is also presenting with asymptomatic hypercalcemia and a positive HLA B27, without evidence of spondilytis. We are discussing the association of two genetic illnesses, with an active form of ankylosing spondilytis diagnosed at a female patient and at an older age than usual.