ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2019) 63 P869 | DOI: 10.1530/endoabs.63.P869

An unusual case of classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency diagnosed in the adulthood

Cristina Lorenzo González, María Teresa Herrera Arranz, María Pilar Olvera Márquez, Yolanda Zambrano Huerta, Javier García Fernández, Elena Márquez Mesa & Jose Enrique Palacio Abizanda

Hospital Universitario Nuestra Señora de La Candelaria, Santa Cruz de Tenerife, Spain.

Introduction: Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (classic 21-OHD CAH) is the most common form of congenital adrenal hyperplasia, characterized by simple virilizing or salt wasting forms. The saline loss picture develops after birth and it can evolve in a short time to a severe picture of hypotonic dehydration and hypovolemic shock with lethal consequences if not diagnosed and treated. Herein we present an unusual case of classic 21-OHD CAH with salt wasting diagnosed in the adulthood.

Case report: A 46-year-old man with no relevant personal history was admited in Internal Medicine department referring astenia, nausea and vomiting and with important dehydratation and hypotension. Laboratory tests revealed a severe hyponatremia (104 mmol/L) and hyperkalaemia (6.2 mmol/L) with elevation of plasma ACTH (662 pg/ml) and low cortisol levels (0.43 mcg/dl). Abdomen CT-scan was normal except for hyperplastic adrenal glands with a pseudonodular imagen of 1.7 cm on the right one. After starting treatment with corticosteroids and mineralocorticoids, it improved both clinically and analytically so he was discharged with Addison disease diagnosis. Few weeks later he was reviewed in Endocrinology consults and we completed the study finding negative anti-adrenal antibodies and elevated levels of 17 OH progesterone (>8 mcg/l) that were confirmed with a second test. In this point, we asked for a genetic study which revealed the presence of 2 severe mutations: mutation 655G of intron 2 (related to salt wasted forms) and mutation Ile172Asn of exon 4 strongly related to simple virilizing forms. In addition, by questioning the patient, he revealed that he had twin brothers who died short time after birth, but he did not know the reason. According to this, the diagnosis changed to classic 21-OHD CAH with one severe mutation for salt wasting form and one severe mutacion for virilizing form, that is the reason why probably our patient could survive until adulthood without any treatment.

Conclusions: Classic 21-OHD CAH englobe a heterogeneous group of clinical pictures, which can manifest in the neonatal period, in childhood, in adolescence or in adulthood and where the synthesis of glucocorticoids, mineralocorticoids and androgens can be affected globally or partially.