Isabelle Benoit, Delphine Drui, Lucy Chaillous, Benoît Dupas, Jean-François Mosnier, Bernard Charbonnel and Bertrand Cariou
Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive ACTH-resistance syndrome characterized by glucocorticoid deficiency in the absence of mineralocorticoid deficiency. Here, we report the case of a young woman with a corticotroph pituitary adenoma as the initial presentation of FGD.
A 15-year-old girl was referred to our institution for a 16 mm pituitary adenoma associated with glucocorticoid deficiency. Clinical and biological features were evocative of FGD. DNA sequencing did not identify mutations in either the melanocortin 2 receptor (MC2R) or the MC2R accessory protein genes, indicating type 3 FGD. Despite adequate glucocorticoid replacement, plasma ACTH levels remained increased and pituitary magnetic resonance imaging (MRI) showed a progression of the tumour size resulting in optic chiasm compression with intra-tumoural haemorrhaging. When the patient was 26 years old, it was decided that she would undergo transsphenoidal surgery. The histomorphological analysis identified a well-individualized pituitary adenoma immunoreactive for ACTH. The proband's sister also exhibited type 3 FGD associated with pituitary hyperplasia upon MRI.
This case highlights the relationship between FGD and hyperplasia of ACTH-producing cells, potentially leading to histologically proven pituitary corticotroph adenomas. This observation raises the question of the pituitary MRI's significance in the follow-up of FGD.
Helton Estrela Ramos, Melina Morandini, Aurore Carré, Elodie Tron, Corinne Floch, Laurent Mandelbrot, Nathalie Neri, Benoit De Sarcus, Albane Simon, Jean Paul Bonnefont, Jeanne Amiel, Isabelle Desguerre, Vassili Valayannopoulos, Mireille Castanet and Michel Polak
Monocarboxylate transporter 8 (MCT8 or SLC16A2) mutations cause X-linked Allan–Herndon–Dudley syndrome. Heterozygous females are usually asymptomatic, but pregnancy may modify thyroid function and MCT8 is expressed in the placenta, suggesting that maternal and fetal abnormalities might develop even in the absence of MCT8 fetal mutation. Genetic counseling is so far based on X-linked transmission, and prenatal diagnosis is rarely performed.
To describe thyroid function and the prenatal diagnosis in pregnant mothers harboring heterozygous MCT8 mutations and management of the persistent maternal hypothyroxinemia.
Two women heterozygous for MCT8 mutations (c.1690G>A and c.1393-1G>C) were monitored throughout pregnancy.
Prenatal diagnosis included sex determination, direct MCT8 sequencing, and familial linkage analysis. Ultrasonography and hormonal assays for maternal thyroid function evaluation were performed serially during pregnancy. Neonatal thyroid hormonal status was assessed.
None of the three fetuses (two males and one female) carried MCT8 mutations. One of the two heterozygous mothers revealed gestational hypothyroxinemia, prompting early levothyroxine (l-T4) therapy until delivery. The second heterozygous mother showed normal thyroid function but was preventively traited by l-T4 and all of the three neonates had normal thyroid hormone levels and thyroid gland at birth, suggesting advantages of prenatal care and/or compensatory mechanisms.
Heterozygous MCT8 women should be monitored for requirement of l-T4 therapy to prevent fetal and neonatal hypothyroidism and to avoid risk of potential cognitive delay due to gestational hypothyroxinemia. Moreover, when the disease-causing mutation is known and/or the first child is affected, prenatal diagnosis for male fetuses should be assessed early for MCT8 mutations by direct sequencing.
Sophie Moniez, Catherine Pienkowski, Benoit Lepage, Safouane Hamdi, Myriam Daudin, Isabelle Oliver, Béatrice Jouret, Audrey Cartault, Gwenaelle Diene, Alain Verloes, Hélène Cavé, Jean-Pierre Salles, Maithé Tauber, Armelle Yart and Thomas Edouard
Abnormalities in the hypothalamo–pituitary–gonadal axis have long been reported in Noonan syndrome (NS) males with only few data available in prepubertal children.
The aim of this study was to describe the gonadal function of NS males from childhood to adulthood.
It is a retrospective chart review.
Patients and methods
A total of 37 males with a genetically confirmed diagnosis of NS were included. Clinical and genetic features, as well as serum hormone levels (LH, FSH, testosterone, anti-Müllerian hormone (AMH), and inhibin B) were analysed.
Of the 37 patients, 16 (43%) children had entered puberty at a median age of 13.5 years (range: 11.4–15.0 years); age at pubertal onset was negatively correlated with BMI SDS (r = −0.541; P = 0.022). In pubertal boys, testosterone levels were normal suggesting a normal Leydig cell function. In contrast, NS patients had significant lower levels of AMH (mean SDS: −0.6 ± 1.1; P = 0.003) and inhibin B (mean SDS: −1.1 ± 1.2; P < 0.001) compared with the general population, suggesting a Sertoli cell dysfunction. Lower AMH and inhibin B levels were found in NS-PTPN11 patients, whereas these markers did not differ from healthy children in SOS1 patients. No difference was found between cryptorchid and non-cryptorchid patients for AMH and inhibin B levels (P = 0.43 and 0.62 respectively). Four NS-PTPN11 patients had a severe primary hypogonadism with azoospermia/cryptozoospermia.
NS males display Sertoli cell-specific primary testicular insufficiency, whereas Leydig cell function seems to be unaffected.