Unsuspected malabsorption as a cause of severe acute hypocalcemia in a treated-autoimmune hypoparathyroidism (APS1)
X. Wang*a (Dr), B. Vokaerb (Pr), L. Amininejadc (Dr), B. Corvilaina (Pr), N. Driessensa (Pr)
a Hôpital Erasme, Service d'endocrinologie, Université Libre de Bruxelles, Belgium, Bruxelles, BELGIQUE ; b Hôpital Erasme, Service de médecine interne, Université Libre de Bruxelles, Belgium, Bruxelles, BELGIQUE ; c Hôpital Erasme, Service de gastroentérologie, Université Libre de Bruxelles, Belgium, Bruxelles, BELGIQUE
* xiaoxiao.wang@erasme.ulb.ac.be
Autoimmune polyendocrinopathy type 1 (APS1), or APECED syndrome, is a rare genetic disease. Auto-immune hypoparathyroidism is usually the first clinical manifestation and the most prevalent disease. Treatment will depend on the affected organ and could be challenging throughout life, especially because of development of combination of different auto-immune disorders.
A 22-year-old woman was diagnosed for hypoparathyroidism at the age of 4 after seizure caused by hypocalcemia. At 14-year-old, she developed an ovarian failure. At that time, APS1 was confirmed by molecular analysis showing a mutated AIRE gene. Serum calcium was stable over time under oral calcium (1.5 g/day) and calcitriol (0.75 µg/day). Despite persistent adherence to the treatment, she was admitted for severe acute hypocalcemia (corrected serum calcium 1.3 mmol/L). In addition to hypocalcemia related-tetany, she complained of abdominal pain and diarrhea. Biology revealed inflammatory syndrome. Repeated microbiological samples remained negative. Acute treatment was initiated with intravenous administration of calcium gluconate. Persisting hypocalcemia required increased oral doses of calcium (4 g/day) and calcitriol (2 µg/day). 1,25-dihydroxy-vitamin D raised slightly despite the doubling of calcitriol dose [from 28.5 to 50.5 pg/ml (N: 22-111)].
Therefore, malabsorption syndrome was suspected and finally confirmed by the presence of a steatorrhea with a steatocrit value of 82%.
High dose of calcium and calcitriol use is limited by the risk of hypercalcemia and by side effects as nephrolithiasis. This case illustrates the necessity to test new therapies like subcutaneous recombinant PTH that could be a good alternative for patients with hypoparathyroidism associated with malabsorption.
L’auteur n’a pas transmis de déclaration de conflit d’intérêt.