Long-term follow-up of prenatally treated children at risk for congenital adrenal hyperplasia: does dexamethasone cause behavioural problems?

OBJECTIVES

To investigate the long-term effects of prenatal treatment of congenital adrenal hyperplasia (CAH) with emphasis on behavioural problems and temperament.

DESIGN

A population-based long-term follow-up study of Swedish children at risk for virilising CAH, who had received treatment prenatally with dexamethasone (DEX). The questionnaire-based follow-up was performed when the children had reached school age.

METHODS

Standardised parent-completed questionnaires were used to evaluate adaptive functioning, behavioural/emotional problems and psychopathology, social anxiety and temperament in DEX-exposed school-aged children (n=26) and matched controls (n=35). In addition, the association between parental questionnaires and children's self-ratings was investigated.

RESULTS

There were no statistically significant differences between DEX-exposed children and controls in measures of psychopathology, behavioural problems and adaptive functioning. In a questionnaire on temperamental traits, DEX-exposed children were described by their parents as being more sociable than controls (P=0.042). The correlation analysis showed only modest parent-child agreement on social anxiety, i.e. the increased social anxiety in children's self-ratings was not confirmed by their parents.

CONCLUSIONS

DEX-treated children showed good overall adjustment. The parent-child agreement with respect to social anxiety was modest, highlighting the importance of multiple information sources and assessment methods. The clinical significance of the observed difference in sociability cannot be determined within the frameworks of this study. Additional studies of larger cohorts are essential to make more decisive conclusions on the safety of the treatment. Until then, it is important that parents are thoroughly informed about the benefits and potential risks and uncertainties of this controversial treatment.

P450 oxidoreductase deficiency - a new form of congenital adrenal hyperplasia

Patients with adrenal insufficiency, genital anomalies and bony malformations resembling the Antley- Bixler syndrome (a craniosynostosis syndrome), are likely to have P450 oxidoreductase (POR) deficiency. Since our first report in 2004, about 26 recessive POR mutations have been identified in 50 patients. POR is the obligate electron donor to all microsomal (type II) P450 enzymes, including the steroidogenic enzymes CYP17A1, CYP21A2 and CYP19A1. POR deficiency may cause disordered sexual development manifested as genital undervirilization in 46,XY newborns as well as overvirilization in those who are 46,XX. This may be explained by impaired aromatization of fetal androgens which may also lead to maternal virilization and low urinary estriol levels during pregnancy. A role for the alternate 'backdoor' pathway of androgen biosynthesis, leading to dihydrotestosterone production bypassing androstenedione and testosterone, has been suggested in POR deficiency but remains unclear. POR variants may play an important role in drug metabolism, as most drugs are metabolized by hepatic microsomal P450 enzymes. However, functional assays studying the effects of specific POR mutations on steroidogenesis showed that several POR variants impaired CYP17A1, CYP21A2 and CYP19A1 activities to different degrees, indicating that each POR variant must be studied separately for each potential target P450 enzyme. Thus, the impact of POR mutations on drug metabolism by hepatic P450s requires further investigation.

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.

A Case of 3β-Hydroxysteroid Dehydrogenase Type II (HSD3B2) Deficiency Picked up by Neonatal Screening for 21-Hydroxylase Deficiency: Difficulties and Delay in Etiologic Diagnosis

BACKGROUND

3beta-Hydroxysteroid dehydrogenase type II deficiency, a rare form of congenital adrenal hyperplasia, is characterized by varying degrees of salt loss and incomplete masculinization in males and mild virilization or normal external genitalia in females. The clinical signs may be difficult to recognize, increasing the risk of a neonatal adrenal crisis. In addition, elevated 17alpha-hydroxyprogesterone and androstenedione levels due to peripheral HSD3B1 activity may lead to a delay of the correct diagnosis and even to misdiagnosis as CYP21 deficiency.

METHOD

We report a patient who was detected on neonatal screening for 21-hydroxylase deficiency, in part because of cross-reactivity in the commonly used assay.

RESULTS

The diagnostic difficulties in this case were overcome by the use of more specific antibodies.

CONCLUSION

This case emphasizes the importance of confirming the etiological diagnosis with molecular genetic analyses.

Congenital adrenal hyperplasia: focus on the molecular basis of 21-hydroxylase deficiency

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder caused by defects in one of several steroidogenic enzymes involved in the synthesis of cortisol from cholesterol in the adrenal glands. More than 90% of cases are caused by 21-hydroxylase deficiency, and the severity of the resulting clinical symptoms varies according to the level of 21-hydroxylase activity. 21-Hydroxylase deficiency is usually caused by mutations in theCYP21A2gene, which is located on the RCCX module, a chromosomal region highly prone to genetic recombination events that can result in a wide variety of complex rearrangements, such as gene duplications, gross deletions and gene conversions of variable extensions. Molecular genotyping ofCYP21A2and the RCCX module has proved useful for a more accurate diagnosis of the disease, and prenatal diagnosis. This article summarises the clinical features of 21-hydroxylase deficiency, explains current understanding of the disease at the molecular level, and highlights recent developments, particularly in diagnosis.

17-Hydroxyprogesterone deficiency as a cause of sexual infantilism and arterial hypertension: laboratory and molecular diagnosis--a case report

The differential diagnosis of hypertension associated with hypokalemia in infancy and adolescence should necessarily include deficiency of the 17alpha-hydroxylase enzyme, a rare form of congenital adrenal hyperplasia (CAH). In addition to hypertension, the classic syndrome caused by this deficiency is characterized by suppressed production of sex hormones and consequently sexual infantilism. Although rare (1% of all forms of CAH), there appears to be a higher incidence of this syndrome in some population groups. This is a case report on two sisters followed up at the Department of Obstetrics and Gynecology, School of Medicine, Universidade Estadual de Campinas (UNICAMP), who were both found to have the 46,XY genotype with homozygosis for W406R, exon 7 of the CYP17 gene (OMIM 202110). The condition was diagnosed only at puberty when hypergonadotropic hypogonadism resulted in sexual infantilism; however, arterial hypertension had been present since infancy and late diagnosis and lack of timely adequate treatment resulted in complications.

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

AIMS

Conflicting results exist regarding bone mineral density (BMD), metabolism and reproductive function of adult patients with congenital adrenal hyperplasia (CAH). We evaluated the long-term outcome and the impact of chronic glucocorticoid replacement in these patients.

METHODS

Physical characteristics, serum hormone concentrations, BMD and metabolism were studied in 45 consecutive CAH adult patients.

RESULTS

Among the 36 women, only 14 (39%) had regular menses. Among the 27 women with classical CAH, the mean number of surgical reconstructions of virilized genitalia was 2.1 +/- 0.2. Twenty of them (74%) were sexually active. Three men presented with testicular adrenal rest tumors. Twenty-five patients (55%) had decreased BMD at the femoral neck and/or at the lumbar spine. BMI was correlated with the BMD T-score at the femoral neck (p < 0.001) and at the lumbar spine (p < 0.01). Hydrocortisone dose was negatively correlated with the BMD T-score at the femoral neck (p = 0.04). Subjects with osteopenia had a significantly lower BMI and received higher hydrocortisone dose than those with normal BMD. Overweight was found in 21 patients (47%). There was a significantly positive correlation between HOMA and BMI (p < 0.001), and between HOMA and 17-OHP levels (p = 0.016).

CONCLUSIONS

Adult patients with CAH treated with long-term glucocorticoids are at risk for decreased BMD, increased BMI, and disturbed reproductive function.

The human fetal adrenal cortex and the window of sexual differentiation

Understanding normal development is fundamental to appreciating postnatal morphology, physiology and, in some instances, pathophysiology. Developmental biology tends to interrogate models in nonprimate species, for instance the mouse, where genetic manipulation gives privileged insight into the function of particular genes. Some human developmental processes, as occur in the adrenal gland, are not faithfully reproduced in these rodent models, yet have an impact on the pathophysiology and treatment of endocrine disorders, such as congenital adrenal hyperplasia. In this setting, in vitro research of normal human development complements clinical investigation of patients born with congenital disorders.

Puberty-related influences on brain development

Puberty is a time of striking changes in cognition and behavior. To indirectly assess the effects of puberty-related influences on the underlying neuroanatomy of these behavioral changes we will review and synthesize neuroimaging data from typically developing children and adolescents and from those with anomalous hormone or sex chromosome profiles. The trajectories (size by age) of brain morphometry differ between boys and girls, with girls generally reaching peak gray matter thickness 1-2 years earlier than boys. Both boys and girls with congenital adrenal hyperplasia (characterized by high levels of intrauterine testosterone), have smaller amygdala volume but the brain morphometry of girls with CAH did not otherwise significantly differ from controls. Subjects with XXY have gray matter reductions in the insula, temporal gyri, amygdala, hippocampus, and cingulate-areas consistent with the language-based learning difficulties common in this group.

Molecular model of human CYP21 based on mammalian CYP2C5: structural features correlate with clinical severity of mutations causing congenital adrenal hyperplasia

Enhanced understanding of structure-function relationships of human 21-hydroxylase, CYP21, is required to better understand the molecular causes of congenital adrenal hyperplasia. To this end, a structural model of human CYP21 was calculated based on the crystal structure of rabbit CYP2C5. All but two known allelic variants of missense type, a total of 60 disease-causing mutations and six normal variants, were analyzed using this model. A structural explanation for the corresponding phenotype was found for all but two mutants for which available clinical data are also discrepant with in vitro enzyme activity. Calculations of protein stability of modeled mutants were found to correlate inversely with the corresponding clinical severity. Putative structurally important residues were identified to be involved in heme and substrate binding, redox partner interaction, and enzyme catalysis using docking calculations and analysis of structurally determined homologous cytochrome P450s (CYPs). Functional and structural consequences of seven novel mutations, V139E, C147R, R233G, T295N, L308F, R366C, and M473I, detected in Scandinavian patients with suspected congenital adrenal hyperplasia of different severity, were predicted using molecular modeling. Structural features deduced from the models are in good correlation with clinical severity of CYP21 mutants, which shows the applicability of a modeling approach in assessment of new CYP21 mutations.

Audit of care of patients with congenital adrenal hyperplasia due to 21-Hydroxylase deficiency in a referral hospital in South India

We carried out an audit of management of patients with 21-Hydroxylase deficiency CAH who presented to the Department of Endocrinology OPD from 1999 till 2004 and had a minimum follow up of 6 months. Of the 30 patients analysed 24 were girls and 6 were boys. The majority belonged to the Christian community. One third had a history of consanguinity or family history of similar illness. Sex assignment was appropriate in most. Karyotyping was done in half. Half the patients had adequate follow up and 17 OHP measurements. Only 7 out of 30 children had normal height for age. Bone age was done in 16 patients only. Most were on hydrocortisone. The average age of genital surgery was 31 months.

[Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency]

Congenital adrenal hyperplasia is a general term applied to a group of several inherited enzymatic defects of cortisol biosynthesis. The most frequent cause of this disease is by far 21-hydroxylase deficiency which is considered one of the commonest metabolic disorders. The degree to which the activity of this enzyme is diminished correlates with the severity of congenital adrenal hyperplasia and therefore the clinical presentation of 21-hydroxylase deficiency has a wide spectrum of clinical and laboratory abnomalities. The recent developments have improved prenatal diagnosis and treatment of affected females to minimise genital virilisation. Despite progress made in its recognition and treatment, diagnosis and management of 21-hydroxylase deficiency is still the subject of many debates and controversies. In this paper, aetiology, symptoms, diagnosis and treatment of 21-hydroxylase deficiency in various groups are reviewed with putting special emphasis on the results of recently published studies.

Female pseudohermaphroditism due to classical 21-hydroxylase deficiency and insulin resistance in a girl with Turner syndrome

We report five-year-old girl with female pseudohermaphroditism due to classical form of 21-hydroxylase deficiency associated with Turner's syndrome (45,X/46,XX) and insulin resistance. She had clitoromegaly since birth, but Turner's syndrome and 21-hydroxylase deficiency were diagnosed incidentally at one and five years of age, respectively. Moreover, we determined insulin resistance, which resolved following corticosteroid therapy for disease. We regard the rare combination as a coincidental occurrence. We stress that adrenal function should be assessed, at least in the presence of clitoral enlargement, in patients with Turner's syndrome, particularly if their karyotype does not contain a Y chromosome. We conclude that chronic hypersecretion of androgen precursors due to an inborn error of metabolism can induce a reduction in insulin sensitivity. Improvement in insulin resistance after treatment of hyperandrogenism has not been previously reported.

Recent advances in the diagnosis and management of congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Congenital adrenal hyperplasias (CAH) are inherited defects of cortisol biosynthesis. More than 90% of CAH are caused by 21-hydroxylase deficiency (21-OHD), found in 1:10 000 to 1:15 000 live births. Females with 'classical' 21-OHD, being exposed to excess androgens prenatally, are born with virilized external genitalia. Potentially lethal adrenal insufficiency is characteristic of two-thirds to three-quarters of patients with the classical salt wasting (SW) form of 21-OHD. Non-SW 21-OHD may be diagnosed on genital ambiguity in affected females, and/or later on the occurrence of androgen excess in both sexes. Non-classical 21-OHD, detected in > or =1:100 of certain populations, may present as precocious pubarche in children or polycystic ovarian syndrome in young women. 21-OHD is caused by mutations in the CYP21 gene encoding the steroid 21-hydroxylase enzyme. More than 90% of these mutations result from intergenic recombination between CYP21 and the closely linked CYP21P pseudogene. The degree to which each mutation compromises enzymatic activity is strongly correlated with the clinical severity of the disorder. This close association between genotype and phenotype makes it possible to predict clinical outcome in affected subjects. The risk of SW and prenatal virilization can be estimated, and overtreatment can be avoided in mildly affected cases. Glucocorticoid and mineralocorticoid replacement therapies are the mainstays of treatment, but additional therapies are being developed. A first trimester prenatal diagnosis should be proposed in families in whom molecular studies have been performed previously. The state of heterozygotism can be predicted by hormonal testing and confirmed by molecular studies. Prenatal diagnosis by direct mutation detection in previously genotyped families permits prenatal treatment of affected females in order to avoid or minimize genital virilization. Neonatal screening by hormonal methods identifies affected children before SW crises develop, reducing mortality in this disorder.

[Case report: congenital adrenal hyperplasia and ambiguous genitalia due to 3 beta-hydroxysteroid dehydrogenase deficiency]

3 beta-hydroxysteroid dehydrogenase deficiency is a disorder of steroid biosynthesis resulting in decreased production of all 3 groups of adrenal steroids. The symptomatology includes congenital adrenal hyperplasia disorders and ambiguous genitalia in 46, XY males. 3beta-HSD deficiency is a rare autosomal recessive genetic disorder. Much heterogeneity exists in the clinical presentation of this disorder.

Recent developments and new applications of tandem mass spectrometry in newborn screening

PURPOSE OF REVIEW

To summarize recent developments in the field of newborn screening related to the use of tandem mass spectrometry as an analytic platform.

RECENT FINDINGS

Novel inborn errors of metabolism with informative amino acid and/or acylcarnitine profiles have been characterized, increasing the complexity of the differential diagnosis of abnormal results. In addition, methods have been developed for the analysis in dried blood spots of steroids and lysosomal enzymes. Previously unrecognized genotype/phenotype correlations have been found among cohorts of patients whose conditions were diagnosed by screening rather than clinically. Several government entities and professional organizations have issued position statements on newborn screening, and worldwide outcome studies continue to underscore the clinical and financial benefits of expanded newborn screening.

SUMMARY

Although it is done inconsistently, newborn screening in the United States is undergoing a rapid expansion driven by the introduction of tandem mass spectrometry in at least 34 state programs. This technology is also used to detect disease markers beyond acylcarnitines and amino acids, as both primary and second-tier tests. In addition to analytic improvements, there is a trend toward the development of joint programs not limited to contiguous geographic areas, often based upon public-private partnerships. This review will summarize several new developments in the field that have occurred since early 2003 and will mention others likely to occur in the near future.

Aldosterone synthase deficiency and related disorders

Aldosterone's main actions are to regulate intravascular volume and serum electrolytes by controlling sodium absorbtion and potassium excretion in the distal nephron. Inherited defects in aldosterone biosynthesis thus cause hypovolemia, hyponatremia and hyperkalemia. Defective aldosterone biosynthesis may be caused by congenital adrenal hyperplasia due to 21-hydroxylase (CYP21) deficiency, in which case cortisol biosynthesis is also affected, or as an isolated defect termed aldosterone synthase (corticosterone methyloxidase, CYP11B2) deficiency. Many mutations have been documented in each of these genes; in general enzymatic activity must be reduced to <1% of normal for aldosterone biosynthesis to be impaired. An additional form of familial hyperreninemic hypoaldosteronism has been described that is not due to mutations in CYP11B2, but its etiology remains to be elucidated.