21-hydroxylase deficiency: an exemplary model of the contribution of molecular biology in the understanding and management of the disease

A proof of concept of a machine learning algorithm to predict late-onset 21-hydroxylase deficiency in children with premature pubic hair

In children with premature pubarche (PP), late onset 21-hydroxylase deficiency (21-OHD), also known as non-classical congenital adrenal hyperplasia (NCCAH), can be routinely ruled out by an adrenocorticotropic hormone (ACTH) test. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a quantitative assay of the circulating steroidome can be obtained from a single blood sample. We hypothesized that, by applying multivariate machine learning (ML) models to basal steroid profiles and clinical parameters of 97 patients, we could distinguish children with PP from those with NCCAH, without the need for ACTH testing. Every child presenting with PP at the Trousseau Pediatric Endocrinology Unit between 2016 and 2018 had a basal and stimulated steroidome. Patients with central precocious puberty were excluded. The first set of patients (year 1, training set, n = 58), including 8 children with NCCAH verified by ACTH test and genetic analysis, was used to train the model. Subsequently, a validation set of an additional set of patients (year 2, n = 39 with 5 NCCAH) was obtained to validate our model. We designed a score based on an ML approach (orthogonal partial least squares discriminant analysis). A metabolic footprint was assigned for each patient using clinical data, bone age, and adrenal steroid levels recorded by LC-MS/MS. Supervised multivariate analysis of the training set (year 1) and validation set (year 2) was used to validate our score. Based on selected variables, the prediction score was accurate (100%) at differentiating premature pubarche from late onset 21-OHD patients. The most significant variables were 21-deoxycorticosterone, 17-hydroxyprogesterone, and 21-deoxycortisol steroids. We proposed a new test that has excellent sensitivity and specificity for the diagnosis of NCCAH, due to an ML approach.

Molecular Diagnosis of Steroid 21-Hydroxylase Deficiency: A Practical Approach

Adrenal insufficiency in paediatric patients is mostly due to congenital adrenal hyperplasia (CAH), a severe monogenic disease caused by steroid 21-hydroxylase deficiency (21-OHD, encoded by the CYP21A2 gene) in 95% of cases. CYP21A2 genotyping requires careful analyses that guaranty gene-specific PCR, accurate definition of pseudogene-gene chimeras, gene duplications and allele dropout avoidance. A small panel of well-established disease-causing alterations enables a high diagnostic yield in confirming/discarding the disorder not only in symptomatic patients but also in those asymptomatic with borderline/positive results of 17-hydroxyprogesterone. Unfortunately, the complexity of this locus makes it today reluctant to high throughput techniques of massive sequencing. The strong relationship existing between the molecular alterations and the degree of enzymatic deficiency has allowed genetic studies to demonstrate its usefulness in predicting/classifying the clinical form of the disease. Other aspects of interest regarding molecular studies include its independence of physiological variations and analytical interferences, its usefulness in the diagnosis of simple virilizing forms in males and its inherent contribution to the genetic counseling, an aspect of great importance taking into account the high carrier frequency of CAH in the general population. Genetic testing of CYP21A2 constitutes an irreplaceable tool to detect severe alleles not just in family members of classical forms but also in mild late-onset forms of the disease and couples. It is also helpful in areas such as assisted reproduction and preimplantation diagnosis. Molecular diagnosis of 21-OHD under expert knowledge definitely contributes to a better management of the disease in every step of the clinical course.

Assessment of cardiac function in children with congenital adrenal hyperplasia: a case control study in Cameroon

BACKGROUND

High level of androgens found in congenital adrenal hyperplasia (CAH) seems to have a deleterious effect on heart function. We therefore evaluate cardiac function of children with CAH in comparison with a healthy group.

METHODS

We carried out a case-control study in the single endocrinology unit of the Mother and Child Center of Chantal Biya's Foundation. Cases were matched for age and genotypic sex to 2 healthy controls. We analyzed the ejection fraction (LVEF), fractional shortening and left ventricular mass; output and cardiac index; E and A waves velocities, E/A ratio and the mitral deceleration time and diameter of the left atrium; tricuspid annular plane systolic excursion and pulmonary artery systolic pressure were also measured.

RESULTS

We included 19 patients with a median age of 6.26 ± 3.75 years and 38 controls stackable distribution. The left ventricular mass of cases was greater than that of controls. A case of reversible cardiomyopathy on hormone replacement therapy was found. For the cases, the average ejection fraction was 71.95 ± 7.88%; the average fractional shortening was 40.67 ± 7.02%. All these values ​​were higher than those of controls, although the difference was not statistically significant. Diastolic left ventricular function was more impaired among the cases. Right ventricular function was similar in both groups. These abnormalities were highly correlated to the late age at diagnosis and duration of treatment.

CONCLUSION

This study shows an altered cardiac function in CAH compared to healthy control and highlights importance of an early diagnosis of cases, a tight control of androgens levels and a regular monitoring of cardiac function.

[Recommendations for the diagnosis and treatment of classic forms of 21-hydroxylase-deficient congenital adrenal hyperplasia]

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is an autosomal recessive disorder caused by mutations in the CYP21A2 gene. Cortisol and aldosterone synthesis are impaired in the classic forms (adrenal insufficiency and salt-wasting crisis). Females affected are virilised at birth, and are at risk for genital ambiguity. In this article we give recommendations for an early as possible diagnosis and an appropriate and individualised treatment. A patient and family genetic study is essential for the diagnosis of the patient, and allows genetic counselling, as well as a prenatal diagnosis and treatment for future pregnancy.

Ten-year evaluation of a Neonatal Screening Program for congenital adrenal hyperplasia

OBJECTIVE

Evaluate the Neonatal Screening Program (NSP) for congenital adrenal hyperplasia (CAH) of the Department of Health of the State of Santa Catarina (Secretaria de Estado da Saúde de Santa Catarina, SES/SC), and provide information to improve the program.

SUBJECTS AND METHODS

Descriptive, retrospective study of 748,395 children screened between January 2001 and December 2010. We analyzed the coverage of the NSP-SES/SC prevalence of CAH, child's age when the first sample for 17-hydroxyprogesterone (17OHP) measurement was collected, levels of 17OHP, mean age at treatment onset and main clinical manifestations.

RESULTS

The NSP-SES/SC covered 89% of the live newborns in the State. It diagnosed 50 cases of CAH, yielding an incidence of 1:14,967. Mean age at collection of the first sample was 7.3 days and mean level of 17OHP was 152.9 ng/mL. The most frequent manifestations were virilized genitalia with nonpalpable gonads, clitoromegaly and genital hyperpigmentation. In three girls, the genre established at birth was incorrect. The salt-wasting form was present in 74% of the cases. There was no occurrence of shock or death. Mean age at treatment onset in the salt-wasting form was 17.4 days compared with 54.9 days in those without the salt-wasting form of the disease. All children were treated with hydrocortisone, and those with salt-wasting CAH were also treated with fludrocortisone.

CONCLUSIONS

The incidence of CAH was 1 case to 14,967 live newborns. Collection of the first sample occurred outside the recommended time, resulting in delays in treatment onset.

Late prenatal dexamethasone and phenotype variations in 46,XX CAH: concerns about current protocols and benefits for surgical procedures

OBJECTIVE

To describe the action of prenatal dexamethasone (PreDex) on the anatomy of female congenital adrenal hyperplasia (CAH) genitalia when started at later stages of gestation.

MATERIALS AND METHODS

Our group follows a large cohort of French CAH patients who underwent PreDex therapy, of whom 258 were recently reported. Four 46,XX patients with a delayed PreDex treatment presented with a virilized genitalia and required surgical reconstruction. This is a retrospective report on genital phenotyping at the time of surgery of these four patients who began PreDex therapy at 8, 12, 20, and 28 weeks of gestation.

RESULTS

Although this series is limited in number, the anatomical description of the length of the genital tubercle, the height of the urethra-vaginal confluence, and the degree of fusion of the genital folds seems to be dependent upon the starting date of PreDex. Most PreDex treatments prescribed up to now have covered the full duration of gestation.

CONCLUSIONS

Our findings suggest that PreDex therapy could be limited to the period of the partitioning window. It is hoped that further prospective multicentric clinical studies will obtain ethical approval in order to elucidate the place and protocols of PreDex therapy in the management of CAH.

[Steroid 21-hydroxylase deficiencies and female infertility: pathophysiology and management]

Steroid 21-hydroxylase deficiency is the most common adrenal genetic disease and is also named congenital adrenal hyperplasia. Depending on the severity of CYP21A2 gene mutations, there are severe or "classical" forms and moderate or "nonclassical" forms of 21-hydroxylase deficiency. The enzyme deficiency causes a disruption of adrenal steroidogenesis, which induces hyperandrogenism and elevated plasma levels of progesterone and 17-hydroxyprogesterone, the two substrates of 21-hydroxylase. These endocrine abnormalities will disrupt gonadal axis, endometrial growth and maturation and finally secretion of cervical mucus. All these phenomena contribute to a female hypofertility. Infertility is more severe in classical forms. When to become pregnant, treatment with hydrocortisone or dexamethasone can limit the production of adrenal androgens and progesterone and improves spontaneous pregnancy rates while minimizing the risk of miscarriage, which is usually relatively high in this disease. When planning pregnancy in patients with a 21-hydroxylase deficiency, genotyping the partner is required to screen for heterozygozity (1/50) and to assess the risk of transmission of a classical form in the progeny.

Long-term outcome of patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

INTRODUCTION

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder affecting adrenal steroid synthesis. In this study, the authors aim to evaluate the impact of CAH due to 21-hydroxylase deficiency on final height (FH), bone health, cardiometabolic risk, fertility, neurocognition and quality of life in a hospital-based sample from Tunisia.

METHODS

Twenty-six patients (11 males and 15 females; mean age: 27.4 ± 8.2 years) were recruited.

RESULTS

Mean FH was 159.5 ± 9.7 cm. Twenty-one patients (80.7%) had a FH below the target height. Ten patients (38.4%) exhibited bone demineralization. Eight patients (30.7%) had obesity. Lipid profile alterations and carbohydrate metabolism disorders were detected in 10 (38.4%) and 5 (19.2%) patients, respectively. Seven patients (27%) had insulin resistance. Ambulatory blood pressure monitoring showed abnormalities in 6 patients (23%). Increased carotid intima-media thickness was found in 14 patients (53.8%). Inhibin B level was decreased in 4 male patients. Semen analysis showed abnormalities in 4 of 10 patients. Testicular tumors were detected in 6 of 11 patients. Anti-Müllerian hormone level was reduced in 4 female patients. Six patients showed poly-cystic ovary syndrome. Brain magnetic resonance imaging showed abnormalities in 11 patients (42.3%). Quality of life was reduced in 14 of 22 patients (63.6%). Many of the suboptimal outcomes appeared to be related to poor adherence to medication schedules, some to overtreatment.

CONCLUSION

CAH patients have a number of issues due to the disease or its treatment. Regular follow-up, early lifestyle interventions, bone health assessment, testicular ultrasound and psychological management are needed.

Metabolic profile and cardiovascular risk factors in adult patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

BACKGROUND

In congenital adrenal hyperplasia (CAH), long-term glucocorticoid treatment coupled with increased androgens may lead to undesirable metabolic effects. The aim of our report was to determine the prevalence of metabolic abnormalities and cardiovascular risk factors in a population of adult patients with CAH due to 21 hydroxylase deficiency.

MATERIALS AND METHODS

Twenty-six patients (11 males and 15 females, mean age ± SD=27.4±8.2 years) were recruited. Anthropometry, body composition, metabolic parameters and cardiovascular risk factors were studied.

RESULTS

Obesity (overweight included) was noted in 16 patients (61.5%), with android distribution in all cases. Bioelectrical impedance showed increased body fat mass in 12 patients (46.1%). Lipid profile alterations and carbohydrate metabolism disorders were detected in seven (26.9%) and five (19.2%) patients respectively. Moderate hepatic cytolysis, associated with hepatic steatosis, was found in one patient. Seven patients (27%) had insulin resistance. Ambulatory blood pressure monitoring showed abnormalities in six patients (23%). Increased carotid intima media thickness was found in 14 patients (53.8%).

CONCLUSION

Adult CAH patients tend to have altered metabolic parameters and a higher prevalence of cardiovascular risk factors. Lifelong follow-up, lifestyle modifications, and attempts to adjust and reduce the glucocorticoid doses seem important.

Hormonal treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency

During childhood, the main aims of the medical treatment of congenital adrenal hyperplasia (CAH) secondary to 21-hydroxylase deficiency, are to prevent salt loss and virilization and to achieve normal stature and normal puberty. As such, there is a narrow therapeutic window through which the intended results can be achieved. In adulthood, the clinical management has received little attention, but recent studies have shown the relevance of long-term follow-up of these patients. Indeed, long-term evaluation of adult CAH patients enables the identification of multiple clinical, hormonal and metabolic abnormalities as bone mineral density alteration, overweight and disturbed reproductive functions. In women with classic CAH, low fertility rate is reported, and is probably the consequence of multiple factors, including neuroendocrine and hormonal factors, feminizing surgery, and psychological factors. Men with CAH may present hypogonadism either through the effect of adrenal rests or from suppression of gonadotropins resulting in infertility. These patients should therefore be carefully followed-up, from childhood through to adulthood, to avoid these complications and to ensure treatment compliance and tight control of the adrenal androgens, by multidisciplinary teams who have knowledge of CAH.