Accuracy of Endocrine Tests for Detecting Hypogonadotropic Hypogonadism in Girls.

OBJECTIVE: To assess the accuracy of inhibin B and the gonadotropin releasing hormone agonist test for the diagnosis of hypogonadotropic hypogonadism (HH). STUDY DESIGN: We performed a retrospective analysis of data collected 2009-2014 using a strict clinical protocol. All prepubertal nonunderweight girls, aged 13-17.5 years with Tanner breast stage B1/B2 and low estradiol levels, were tested and re-examined at 6-month intervals (n = 21). Constitutional delay of growth and puberty was defined by spontaneous menarche; HH was identified by association with specific causes of HH or no spontaneous progress of puberty during follow-up. Inhibin B was measured using enzyme-linked immunosorbent assay, and follicle-stimulating hormone and luteinizing hormone (basal and stimulated by triptorelin) were measured using a chemiluminescence immunoassay. RESULTS: The cohort comprised 12 girls with constitutional delay of growth and puberty and 9 girls with HH. The causes of HH included hypopituitarism (n = 3), Prader-Willi syndrome, chromosomal aberration, intellectual disability syndrome with ataxia, and idiopathic causes (n = 2). Each measurement, basal inhibin B <20 pg/mL or stimulated follicle-stimulating hormone (4 hours) <11 IU/L, demonstrated a sensitivity and a specificity of 100% for the detection of HH. Stimulated luteinizing hormone (4 hours) <9 IU/L showed 100% sensitivity but only 83% specificity. CONCLUSIONS: Inhibin B seems to be the ideal measurement for detecting HH in girls. The gonadotropin releasing hormone agonist test is an alternative diagnostic modality, although this approach is more invasive and laborious.

Health and quality of life in adults with Noonan syndrome.

OBJECTIVE: To obtain information on health and quality of life in adults with Noonan syndrome. STUDY DESIGN: From a cohort of 144 children with the diagnosis of Noonan syndrome whose height data had been published 23 years ago, 103 pediatric files providing adequate data were identified. Participants were sent questionnaires and asked to provide saliva for DNA analysis and to return for physical examination. RESULTS: Ten of 103 individuals had died, 3 of them suddenly (standardized mortality ratio, 3.00; 95% CI, 1.44-5.52). Eighty-one individuals could be contacted by mail, with a positive response from 45. Genotyping in 36 of 45 participants revealed characteristic mutations in 61%. Median age at follow-up was 42.8 years. Mean adult heights were 169.2 cm (men) and 154.4 cm (women). In comparison with the general population, participants had lower educational status and lived more frequently without any partner. According to the response to the Short Form-36 questionnaire, quality of life was not impaired. CONCLUSIONS: Individuals with Noonan syndrome have higher mortality, lower education, and rarely partnership. Quality of life according to self-reported Short Form-36 was good. Men grew taller than previously reported from this cohort.