Molecular analysis and genotype-phenotype correlations in patients with classical congenital adrenal hyperplasia due to 21-hydroxylase deficiency from southern Poland - experience of a clinical center

Genetic and clinical characteristics including occurrence of testicular adrenal rest tumors in Slovak and Slovenian patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

OBJECTIVE

To analyze the mutational spectrum, clinical characteristics, genotype-phenotype correlations, testicular adrenal rests tumor prevalence, and role of neonatal screening in congenital adrenal hyperplasia (CAH) patients from Slovakia and Slovenia.

DESIGN AND METHODS

Data were obtained from 104 patients with CAH registered in Slovak and Slovenian databases. Low-resolution genotyping was performed to detect the most common point mutations. To detect deletions, conversions, point mutations, or other sequence changes in the CYP21A2 gene, high-resolution genotyping was performed. Genotypes were classified according to residual 21-hydroxylase activity (null, A, B, C).

RESULTS

64% of the individuals had the salt-wasting form (SW-CAH), 15% the simple virilizing form (SV-CAH), and 21% the non-classic (NC-CAH). CYP21A2 gene deletion/conversion and c.293-13A/C>G pathogenic variant accounted together for 55.5% of the affected alleles. In SV-CAH p.Ile172Asn was the most common pathogenic variant (28.13%), while in NC-CAH p.Val282Leu (33.33%), CYP21A2 gene deletion/conversion (21.43%), c.293-13A/C>G (14.29%), Pro30Leu (11.90%). The frequency of alleles with multiple pathogenic variants was higher in Slovenian patients (15.83% of all alleles). Severe genotypes (0 and A) correlated well with the expected phenotype (SW in 94.74% and 97.3%), while less severe genotypes (B and C) correlated weaklier (SV in 50% and NC in 70.8%). The median age of SW-CAH patients at the time of diagnosis was 6 days in Slovakia vs. 28.5 days in Slovenia (p=0.01). Most of the Slovak patients in the cohort were detected by NBS. (24 out of 29). TARTs were identified in 7 out of 24 male patients, of whom all (100%) had SW-CAH and all had poor hormonal control. The median age at the diagnosis of TARTs was 13 years.

CONCLUSION

The study confirmed the importance of neonatal screening, especially in the speed of diagnosis of severe forms of CAH. The prediction of the 21-OH deficiency phenotype was reasonably good in the case of severe pathogenic variants, but less reliable in the case of milder pathogenic variants, which is consistent compared to data from other populations. Screening for TARTs should be realized in all male patients with CAH, since there is possible remission when identified early.

Cardiometabolic Health in Adolescents and Young Adults with Congenital Adrenal Hyperplasia

Background and objectives: Data on long-term cardiometabolic consequences in patients with congenital adrenal hyperplasia (CAH) are controversial. The aim of our study was to evaluate body mass index (BMI), body composition, blood pressure (BP) and insulin sensitivity in adolescents and young adults with CAH in comparison with healthy controls. Methods: Thirty-two patients with classical CAH (13 males; mean of age 26.0 ± 7.1, years (14.0−37.3) were compared to 32 healthy sex and age-matched controls (13 males; mean of age 28.7 ± 4.6 years (14.1−37.2), p = 0.13). Body composition was evaluated in all subjects with DXA (Hologic Inc., Bedford, MA, USA). Elevated BP was defined as BP > 95th percentile in adolescents, and >140/90 mmHg in adults. Comparisons between the two groups were adjusted for age, gender, pubertal stage and height. An oral glucose tolerance test was performed, and fasting insulin levels were evaluated. Insulin sensitivity was determined using a homeostasis model assessment of insulin resistance index (HOMA-IR). Results: The median BMI was significantly higher in subjects with CAH (1.63 (0.3−2.4) SDS and 0.41 (−0.63−1.19) SDS, respectively, p < 0.001). Visceral adipose tissue (VAT) in grams was significantly higher in CAH females versus control females (467 (231−561) vs. 226 (164−295), p = 0.002). Elevated BP was identified in 34% of CAH patients (nine SW and two SV) and 12.5% (n = 4) of controls (p = 0.038). Impaired fasting glycemia was detected in one SW CAH patient and impaired glucose tolerance in three SV CAH patients; normal glucose tolerance was found in all controls. A strong positive correlation was found between median cumulative hydrocortisone (HC) dose equivalents and LDL-cholesterol and a negative association with lean body mass (r = −0.79, p = 0.036) in females with CAH. BMI, VAT, BP and HOMA-IR were not related to median cumulative HC dose equivalents. Conclusions: CAH patients had higher BMI, VAT and frequency of elevated BP compared to controls. Doses of glucocorticoids were related directly to LDL-cholesterol and inversely to lean body mass in CAH females, but not associated with body composition, insulin sensitivity and BP in the whole cohort of CAH patients.