New management strategy of pregnancies at risk of congenital adrenal hyperplasia using fetal sex determination in maternal serum: French cohort of 258 cases (2002-2011)

International audienceCONTEXT: Prenatal dexamethasone (DEX) treatment has been proposed since 1984 to prevent genital virilization in girls with congenital adrenal hyperplasia (CAH). DEX is effective in CAH females if initiated before the sixth week of gestation, but its safety in children treated in utero remains controversial regarding cognitive functions.OBJECTIVE: To avoid prenatal DEX in males and initiate DEX in due time in CAH females, we proposed in 2002 a protocol for fetal sex determination in the maternal serum (SRY test).DESIGN AND SETTING: We conducted a retrospective study of the management of 258 fetuses in the period 2002 through 2011 in pregnancies managed in referent medical centers with an institutional practice. PATIENTS: A total of 258 fetuses at risk of CAH (134 males and 124 females) were included.INTERVENTION: DEX was offered after informed consent to pregnant women. MAIN OUTCOME MEASURE: The sensitivity of an early SRY test was evaluated after data collection.RESULTS: The SRY test is sensitive from 4 weeks and 5 days of gestation. It avoided prenatal DEX in 68% of males, and this percentage increased over the years. DEX was maintained until prenatal diagnosis in non-CAH females. Virilization was prevented in 12 CAH girls treated at the latest at 6 weeks gestation and minimized in 3 girls treated between 6 and 7 weeks gestation. Maternal tolerance was correct. No fetal malformations were noted in the 154 children treated in utero.CONCLUSIONS: The SRY test is reliable to avoid prenatal DEX in males, but its application must be improved. Prenatal DEX should be maintained to prevent virilization and traumatic surgery in CAH girls after informed consent and information provided to families about the benefit to risk ratio in limiting hyperandrogenism during fetal life. Our large multicentric French cohort has helped to better assess the risks previously reported

Identification of three clinical neurofibromatosis 1 subtypes: Latent class analysis of a series of 1351 patients

International audienc

Identification of three clinical neurofibromatosis 1 subtypes: Latent class analysis of a series of 1351 patients

International audienc

The expanding spectrum of COL2A1 gene variants IN 136 patients with a skeletal dysplasia phenotype

International audienceHeterozygous COL2A1 variants cause a wide spectrum of skeletal dysplasia termed type II collagenopathies. We assessed the impact of this gene in our French series. A decision tree was applied to select 136 probands (71 Stickler cases, 21 Spondyloepiphyseal dysplasia congenita cases, 11 Kniest dysplasia cases, and 34 other dysplasia cases) before molecular diagnosis by Sanger sequencing. We identified 66 different variants among the 71 positive patients. Among those patients, 18 belonged to multiplex families and 53 were sporadic. Most variants (38/44, 86%) were located in the triple helical domain of the collagen chain and glycine substitutions were mainly observed in severe phenotypes, whereas arginine to cysteine changes were more often encountered in moderate phenotypes. This series of skeletal dysplasia is one of the largest reported so far, adding 44 novel variants (15%) to published data. We have confirmed that about half of our Stickler patients (46%) carried a COL2A1 variant, and that the molecular spectrum was different across the phenotypes. To further address the question of genotype-phenotype correlation, we plan to screen our patients for other candidate genes using a targeted next-generation sequencing approach.European Journal of Human Genetics advance online publication, 2 December 2015; doi:10.1038/ejhg.2015.25