Kyllo, Jennifer

Abstract Background Children with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency typically have height, weight, and body mass index (BMI) growth patterns that differ from the general population due to increased androgen and/or glucocorticoid exposures. With the recent surge in the development of new therapies, CAH-specific growth charts are needed to evaluate the effectiveness of these new treatments. Methods Retrospective data from patients aged 0 to 20 years with classic CAH, confirmed by hormonal testing and/or CYP21A2 genotyping, from 2 large clinical databases were analyzed. Specialized charts were developed using the lamda-mu-sigma semiparametric modeling method to generate CAH-specific percentile curves from 0 to 20 years. Nodal-point analyses were conducted to assess differences in incremental growth at 4, 8, 12, 16, and 20 years of age relative to Centers for Disease Control and Prevention (CDC) 2000 normative charts using 1-sided quantile tests and age of adiposity rebound estimated with curve derivative solutions. Results A total sample of 8692 visits from 515 patients was used. Growth (height-, weight-, BMI-for-age) channels of CAH patients were significantly different over the entire growing period and characterized by diminished pubertal spurt relative to the CDC reference. Onset of adiposity rebound based on BMI-for-age occurred earlier for CAH patients (females 3.3 years, males 3.9 years) compared to their normative counterparts (5-8 years). Conclusion Our study showed that at incremental time points throughout childhood, children with CAH collectively follow specific differences in growth trajectories as compared to unaffected children. These variations highlight the need for CAH-specific charts to assist in clinical management, appraisal of growth trajectories, and assessment of the impact of new therapies.

Abstract Context Single-tier newborn screening (NBS) for congenital adrenal hyperplasia (CAH) using 17-hydroxyprogesterone (17OHP) measured by fluoroimmunoassay (FIA) in samples collected at 24 to 48 hours produces a high false-positive rate (FPR). Second-tier steroid testing can reduce the FPR and has been widely implemented. Objective We investigated the accuracy of an alternative multitier CAH NBS protocol that incorporates molecular testing of the CYP21A2 gene and reduces the first-tier 17OHP cutoff to minimize missed cases. Methods We create a Minnesota-specific CYP21A2 pathogenic variants panel; developed a rapid, high-throughput multiplex, allele-specific-primer-extension assay; and performed a 1-year retrospective analysis of Minnesota NBS results comparing metrics between a conventional steroid-based 2-tier protocol and a molecular-based multitier NBS protocol, applied post hoc. Results CYP21A2 gene sequencing of 103 Minnesota families resulted in a Minnesota-specific panel of 21 pathogenic variants. The Centers for Disease Control and Prevention created a molecular assay with 100% accuracy and reproducibility. Two-tier steroid-based screening of 68 659 live births during 2015 resulted in 2 false negatives (FNs), 91 FPs, and 1 true positive (TP). A 3-tier protocol with a lower first-tier steroid cutoff, second-tier 21-variant CYP21A2 panel, and third-tier CYP21A2 sequencing would have resulted in 0 FNs, 52 FPs, and 3 TPs. Conclusion Incorporation of molecular testing could improve the accuracy of CAH NBS, although some distinct challenges of molecular testing may need to be considered before implementation by NBS programs.

Summary Objectives To evaluate obesity and overweight in children with congenital adrenal hyperplasia ( CAH ) and associations with glucocorticoids, fludrocortisone and disease control. Adjusting body mass index‐for‐height‐age ( BMI HA ) percentile is proposed to correct misclassification of obese/overweight status in CAH children with advanced bone age and tall‐for‐age stature. Design Longitudinal. Patients One hundred and ninety‐four children with CAH seen from 1970 to 2013: 124 salt wasting ( SW ); 70 simple virilizing ( SV ); 102 females. Measurements Body mass index (BMI) end‐points were overweight (85–94 percentile) and obese (≥95 percentile). Results Approximately 50% of the children had at least one BMI measurement ≥95 percentile and about 70% had at least one ≥85 percentile. Using BMI HA percentiles, obesity incidence decreased slightly in SW children (47–43%) and markedly in SV children (50–33%); however, overweight status was not reduced. Only 6% of SW and 1% of SV children were persistently obese (≥3 clinic visits) when BMI HA was applied, whereas overweight status persisted in 35% of SW and 33% of SV children. Most obesity or overweight when using BMI HA occurred before age 10 and there was no association with hydrocortisone (HC) or fludrocortisone dosing. Adiposity rebound for SW children occurred by 3·3 years and in SV females by age 3·8 years, over a year earlier than the adiposity rebound for healthy children. Conclusion Children with CAH are at higher risk for early onset obesity and overweight with or without using BMI HA but rates of persistent obesity were lower than previously reported. Careful HC dosing during early childhood is needed to prevent increased weight gain and an early adiposity rebound.

Summary Objectives Estimates of high blood pressure ( BP ) incidence in children with congenital adrenal hyperplasia ( CAH ) vary widely; risk factors are poorly understood. We estimated incidence of hypertension by CAH subtype and sex, and assessed its association with body mass index, hydrocortisone and fludrocortisone. Design Longitudinal. Patients Chart review of 180 paediatric CAH patients (120 salt wasting; 60 simple virilizing; 93 females) seen from 1970 to 2013. Measurements High BP was diagnosed by diastolic or systolic blood pressure measurement ≥95th percentile for age, sex and height; hypertension was diagnosed with high BP on at least three clinic visits. Results Children with classic CAH who received fludrocortisone had a significantly higher rate of hypertension (55% vs 31%) than those who did not. Hypertension incidence was higher in salt‐wasting CAH (58%) than in simple‐virilizing CAH (35%). Hypertension first occurred before age 5 years in 91% of salt‐wasting males and 50% of cases in salt‐wasting females; most simple‐virilizing cases occurred during ages 10–18 years. Rates of hypertension were higher in children who had three or more measurements with 17‐ OHP < 400 ng/dl (12·12 nmol/l), and this difference was significant in salt‐wasting males. Children on fludrocortisone who had three or more readings of 17‐ OHP < 400 ng/dl (12·12 nmol/l) had a significantly higher rate of hypertension than those who did not. Hydrocortisone dose was not associated with hypertension. Conclusion Children with CAH are at higher risk for hypertension than the general paediatric population, and incidence differs by sex and CAH subtype. Hypertension was higher in children on fludrocortisone and who were oversuppressed.