Endocrine Abstracts

Context: Vitamin D deficiency following malabsorptive bariatric surgery can lead to osteomalacia. We report a patient with severe vitamin D deficiency following malabsorptive bariatric surgery successfully treated with calcifediol but not cholecalciferol.

Case description: A 40-year-old woman, submitted to biliopancreatic diversion 20 years before and chronically treated with 50 000 IU cholecalciferol weekly, was admitted to our Endocrine Unit because of severe low-back pain, muscle weakness, generalized muscular hypotrophy, associated with hypocalcemia and elevated PTH levels. Initial evaluation revealed low albumin-corrected serum calcium (7.4 mg/dl), high serum PTH (240 pg/ml), bone-specific alkaline phosphatase (125 μg/l) and 1,25-dihydroxyvitamin D (112 pg/ml) concentrations, and undetectable serum 25-hydroxyvitamin D (<7 ng/ml). Bone mineral density (BMD) was markedly low. Normocalcemia was initially restored with i.v. albumin and calcium gluconate. Treatment with calcitriol (0.5 μg three times daily) and oral calcium carbonate (1000 mg daily) was simultaneously started and cholecalciferol was replaced with calcifediol (125 μg (5000 UI) daily)). During follow-up the calcifediol dose was progressively tapered to 25 μg (1000 UI) daily and the calcitriol dose progressively reduced and finally withdrawn. Serum biochemistry normalized, BMD significantly increased and the patient’s clinical conditions progressively improved, with a substantial recovery of autonomy.

Conclusions: Our data suggest that calcifediol migth be more efficacious than cholecalciferol for prevention and treatment of vitamin D deficiency in patients treated by malabsorptive bariatric surgery.