CYP21A2 gene mutations in congenital adrenal hyperplasia: genotype-phenotype correlation in Turkish children

Hormonal control during infancy and testicular adrenal rest tumor development in males with congenital adrenal hyperplasia: a retrospective multicenter cohort study

IMPORTANCE

Testicular adrenal rest tumors (TARTs), often found in male patients with congenital adrenal hyperplasia (CAH), are benign lesions causing testicular damage and infertility. We hypothesize that chronically elevated adrenocorticotropic hormone exposure during early life may promote TART development.

OBJECTIVE

This study aimed to examine the association between commencing adequate glucocorticoid treatment early after birth and TART development.

DESIGN AND PARTICIPANTS

This retrospective multicenter (n = 22) open cohort study collected longitudinal clinical and biochemical data of the first 4 years of life using the I-CAH registry and included 188 male patients (median age 13 years; interquartile range: 10-17) with 21-hydroxylase deficiency (n = 181) or 11-hydroxylase deficiency (n = 7). All patients underwent at least 1 testicular ultrasound.

RESULTS

TART was detected in 72 (38%) of the patients. Prevalence varied between centers. When adjusted for CAH phenotype, a delayed CAH diagnosis of >1 year, compared with a diagnosis within 1 month of life, was associated with a 2.6 times higher risk of TART diagnosis. TART onset was not predicted by biochemical disease control or bone age advancement in the first 4 years of life, but increased height standard deviation scores at the end of the 4-year study period were associated with a 27% higher risk of TART diagnosis.

CONCLUSIONS AND RELEVANCE

A delayed CAH diagnosis of >1 year vs CAH diagnosis within 1 month after birth was associated with a higher risk of TART development, which may be attributed to poor disease control in early life.

Characteristics of Congenital Adrenal Hyperplasia Diagnosed in Adulthood: A Literature Review and Case Series

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders characterized by impaired cortisol synthesis. CAH, depending on its clinical form, is usually diagnosed in the neonatal period, later in childhood, in adolescence, or in young adults. Herein, we report a case series of eight individuals in whom CAH was diagnosed between the ages of 18 and 81 years.

METHODS

We report on clinical presentations, hormonal tests, adrenal/gonadal imaging, and genetic findings. The clinical data of eight people with CAH, including four women (46, XX) and four men (46, XY), were reviewed. A genetic analysis of the cytochrome P450 family 21 subfamily A member 2 (CYP21A2) gene was performed in six patients. A comprehensive literature review was also conducted.

CASE SERIES

Partial cortisol deficiency was found in all patients. The most frequent genotype was the homozygotic I173N mutation in CYP21A2. Adrenal masses were detected in seven patients, except for the youngest. Most of the patients were of short stature. Hypogonadotropic hypogonadism was detected in two males, and three females presented with primary amenorrhea. Hirsutism was noticeable in three females. All of the patients developed insulin resistance, and half of them were obese.

CONCLUSIONS

The clinical presentations of different forms of CAH overlapped. Genotype-phenotype correlations were strong but not absolute. The management of CAH should be individualized and based on clinical and laboratory findings. Furthermore, the assessment of the cortisol response to adrenocorticotrophic hormone stimulation should be mandatory in all adults with CAH. Additionally, the regular long-term screening of cardiometabolic status is required in the CAH population.

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.

Syrian females with congenital adrenal hyperplasia: a case series

BACKGROUND

One of the most common types of congenital adrenal hyperplasia is an autosomal recessive disorder with 21-hydroxylase deficiency. The classical form, defined by cortisol insufficiency, is accompanied by prenatal androgen excess causing variable masculinization degrees of external genitalia in babies with a 46, XX karyotype.

CASES PRESENTATION

These five case reports highlight the management of Syrian females aged between 0 and 32 years with congenital adrenal hyperplasia. Two of the patients have been raised as males, while two had reconstructive surgery and one had hormonal therapy. Becoming mother was achieved by two patients CONCLUSION: The integrated treatment of females with classical congenital adrenal hyperplasia CAH, which includes appropriate surgical procedures and controlled hormonal therapy, gives these females the opportunity to live as they are, and perhaps as mothers in the future.

Genotypic spectrum of 21-hydroxylase deficiency in an endogamous population

BACKGROUND

Congenital adrenal hyperplasia (CAH) due to autosomal recessive 21-hydroxylase deficiency (21-OHD) is caused by defects in the CYP21 (CYP21A2) gene. Several mutations have been identified in the CYP21 (CYP21A2) gene of patients with 21-OHD. We aimed at determining the frequency of these mutations among a group of Egyptian patients and studying the genotype-phenotype correlation.

METHODS

Forty-seven patients with CAH due to 21-OHD from 42 different families diagnosed by clinical and hormonal evaluation and classified accordingly into salt wasting (SW) and simple virilizing (SV) phenotypes were enrolled. Their ages ranged between 1.78 and 18.99 years. Molecular analysis of the CYP21 (CYP21A2) gene was performed for the detection of eleven common mutations: P30L, I2 splice (I2 G), Del 8 bp E3 (G110del8nt), I172N, cluster E6 (I236N, V237E, M239K), V281L, L307 frameshift (F306 + T), Q318X, R356W, P453S, R483P by polymerase chain reaction (PCR) and reverse hybridization.

RESULTS

Disease-causing mutations were identified in 47 patients, 55.31% of them were compound heterozygous. The most frequent mutations were I2 splice (25.43%), followed by cluster E6 (16.66%) and P30L (15.78%). Two point mutations (P453S, R483P) were not identified in any patient. In the SW patients, genotypes were more compatible with their phenotypes.

CONCLUSION

Molecular characterization should be considered along with clinical and biochemical diagnosis of CAH since it could confirm the diagnosis, outline the treatment strategy and morbidity, and ensure proper genetic counseling.

Congenital Adrenal Hyperplasia-Current Insights in Pathophysiology, Diagnostics, and Management

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders affecting cortisol biosynthesis. Reduced activity of an enzyme required for cortisol production leads to chronic overstimulation of the adrenal cortex and accumulation of precursors proximal to the blocked enzymatic step. The most common form of CAH is caused by steroid 21-hydroxylase deficiency due to mutations in CYP21A2. Since the last publication summarizing CAH in Endocrine Reviews in 2000, there have been numerous new developments. These include more detailed understanding of steroidogenic pathways, refinements in neonatal screening, improved diagnostic measurements utilizing chromatography and mass spectrometry coupled with steroid profiling, and improved genotyping methods. Clinical trials of alternative medications and modes of delivery have been recently completed or are under way. Genetic and cell-based treatments are being explored. A large body of data concerning long-term outcomes in patients affected by CAH, including psychosexual well-being, has been enhanced by the establishment of disease registries. This review provides the reader with current insights in CAH with special attention to these new developments.

Congenital Adrenal Hyperplasia (CAH) and Gitelman Syndrome (GS): Overlapping Symptoms in an Uncommon Association

Background

Classical salt-wasting (SW) congenital adrenal hyperplasia (CAH) and Gitelman syndrome (GS) are two genetic conditions in which dyselectrolytemia may occur. No association between the two conditions has been previously described. Case Presentation. We present the case of a boy with a neonatal diagnosis of SW-CAH who showed low potassium blood levels from the age of 15 years. This electrolytic alteration was, at first, attributed to an excessive action of mineralocorticoid drugs. Due to persistence of hypokalemia, SLC12A3 whole genome sequencing was performed, showing a heterozygous C to T base pair substitution at position 965 in gene SLC12A3. This mutation is related to Gitelman syndrome with autosomal recessive transmission.

Conclusions

SW-CAH and GS determine opposite values of potassium in the absence of specific therapy, with a natural tendency to compensate each other. The symptom overlap makes diagnosis difficult. Organic causes of hypokalemia in patients undergoing life-saving therapy should not be excluded.

Characteristics of In2G Variant in Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency

Substantial research has been performed during the last decades on the clinical and genetic variability of congenital adrenal hyperplasia (CAH) and its most common form, 21-hydroxylase deficiency (21OHD). CAH is one of the most prevalent autosomal recessive diseases in humans, and it can be divided into classic-further subdivided into salt wasting (SW) and simple virilizing (SV)-and non-classic (NC) forms. Pathogenic variants of CYP21A2 gene, encoding the 21-hydroxylase enzyme, have been reported with variable prevalence in different populations. NM_000500.9:c.293-13C/A>G (In2G) variant represents the most common CYP21A2 gene changes related to the classic 21OHD form. However, the phenotype of In2G carriers is variable depending on the variant homozygous/heterozygous status and combination with other CYP21A2 pathogenic variants. In addition, identical genotypes, harboring the homozygous In2G variant, can present with variable phenotypes including the SW and SV or rarely NC form of the disease. Here, we analyze and present the clinical aspects, genotype/phenotype correlations, and other characteristics related to the CYP21A2 In2G variant.

Clinical outcomes and characteristics of P30L mutations in congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Despite numerous studies in the field of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, some clinical variability of the presentation and discrepancies in the genotype/phenotype correlation are still unexplained. Some, but not all, discordant phenotypes caused by mutations with known enzyme activity have been explained by in silico structural changes in the 21-hydroxylase protein. The incidence of P30L mutation varies in different populations and is most frequently found in several Central and Southeast European countries as well as Mexico. Patients carrying P30L mutation present predominantly as non-classical CAH; however, simple virilizing forms are found in up to 50% of patients. Taking into consideration the residual 21-hydroxulase activity present with P30L mutation this is unexpected. Different mechanisms for increased androgenization in patients carrying P30L mutation have been proposed including influence of different residues, accompanying promotor allele variability or mutations, and individual androgene sensitivity. Early diagnosis of patients who would present with SV is important in order to improve outcome. Outcome studies of CAH have confirmed the uniqueness of this mutation such as difficulties in phenotype classification, different fertility, growth, and psychologic issues in comparison with other genotypes. Additional studies of P30L mutation are warranted.

Assessment of the most common CYP21A2 point mutations in a cohort of congenital adrenal hyperplasia patients from Egypt

Objectives Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is a common autosomal recessive disorder caused by defects in the CYP21A2 gene. We aimed to determine the prevalence of the most commonly reported mutations among 21-OHD Egyptian patients and correlate genotype with phenotype. Methods Molecular analysis of the CYP21A2 gene was performed for the detection of the six most common point mutations (p.P30L, p.I172N, p.V281L, p.Q318X, the splice site mutation Int2 [IVS2-13A/C>G], and the cluster of three mutations [p.I236N, p.V237E, and p.M239K] designed as CL6). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was performed on 47 unrelated Egyptian 21α-OH deficiency patients and their available parents to detect the presence of the six most common point mutations. Results Screening for the six most common point mutations in CYP21A2 gene, revealed mutations in 87.2% (82/94) of the studied alleles corresponding to 47 Egyptian patients. The most common mutation among the studied cases was IVS2-13C/A>G that was found to be presented in a frequency of 46.8% (44/94). The genotype/phenotype correlations related to null, A, and B groups were with PPV of 100, 55.5, and 83.3%, respectively. Conclusions The described method diagnosed CAH in 80.8% of the studied patients. Good correlation between genotype and phenotype in salt wasting and simple virilizing forms is determined, whereas little concordance is seen in nonclassical one. Furthermore, studying the carrier frequency of 21-OHD among the normal population is of great importance.

CYP21A2 Gene Pathogenic Variants: A Multicenter Study on Genotype-Phenotype Correlation from a Portuguese Pediatric Cohort

BACKGROUND

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD) is an autosomal recessive disorder characterized by 3 overlapping phenotypes: salt-wasting (SW), simple virilizing (SV), and non-classic (NC). We aimed at conducting a nationwide genotype description of the CAH pediatric patients and to establish their genotype-phenotype correlation.

METHODS

CAH patients were recruited from Portuguese pediatric endocrinology centers and classified as SW, SV, or NC. Genetic analysis was performed by polymerase chain reaction (sequence specific primer, restriction fragment length polymorphism) or direct Sanger sequencing. Genotypes were categorized into 4 groups (0, A, B, and C), according to their predicted enzymatic activity. In each group, the expected phenotype was compared to the observed phenotype to assess the genotype-phenotype correlation.

RESULTS

Our cohort comprises 212 unrelated pediatric CAH patients (29% SW, 11% SV, 60% NC). The most common pathogenic variant was p.(Val282Leu; 41.3% of the 424 alleles analyzed). The p.(Val282Leu) variant, together with c.293-13A/C>G, p.(Ile173Asn), p.(Leu308Thr), p.(Gln319*), and large deletions/conversions were responsible for 86.4% of the mutated alleles. Patients' stratification by disease subtype revealed that the most frequent pathogenic variants were c.293-13A/C>G in SW (31.1%), p.(Ile173Asn) in SV (46.9%), and p.(Val282Leu) in NC (69.5%). The most common genotype was homozygosity for p.(Val282Leu; 33.0%). Moreover, we found 2 novel variants: p.(Ile161Thr) and p.(Trp202Arg), in exons 4 and 5, respectively. The global genotype-phenotype correlation was 92.4%. Group B (associated with the SV form) showed the lowest genotype-phenotype correlation (80%).

CONCLUSION

Our cohort has one of the largest NC CAH pediatric populations described. We emphasize the high frequency of the p.(Val282Leu) variant and the very high genotype-phenotype correlation observed.

21-Hydroxylase deficiency: Mutational spectrum and Genotype-Phenotype relations analyses by next-generation sequencing and multiplex ligation-dependent probe amplification

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD) is autosomal recessive disorder of cortisol biosynthesis. Genetic defects in CYP21A2 cause 21OHD. The aim of this study was to determine spectrum of mutations in CYP21A2 in a large cohort and analyze the genotype-phenotype correlation to assess predictive characteristics of genotype. We investigated a total of 113 patients with 21OHD. Next-generation sequencing and Multiplex ligation-dependent probe amplification of the CYP21A2 gene were performed in patients and their parents. The genotypes were categorized into Groups 0, A, B, and C according to the residual 21-hydroxylase activities. In this study, the group A was divided into two subgroups as A1 and A2. Three novel variants were found. The genotype-phenotype correlation of the mutation classification was 91.5%. Positive predictivity of subgroups A1 was higher than groups A and subgroups A2. Our study reports genotype-phenotype correlations in the largest 21OHD cohort in Turkey. This correlation sustained when we analyzed our data in combination with metadata from other published studies. This study confirms that CYP21A2 genotyping with next-generation sequencing and MLPA can accurately and reliably confirm the diagnosis of 21OHD. We propose a new classification by dividing group A into two new subgroups to better predict the phenotype. In light of this very high genotype-phenotype correlation, with their ever-increasing availability, declining cost, and turnaround time, we propose that molecular genetic studies can be more economical and practical alternative to the current initial diagnostic laboratory studies based on assays of intermediary steroid metabolites.

Cardiovascular health, growth and gonadal function in children and adolescents with congenital adrenal hyperplasia

After the introduction of replacement therapy with glucocorticoids and mineralocorticoids in the 1950s, congenital adrenal hyperplasia (CAH) is no longer a life-limiting condition. However, due to the successful introduction of medical steroid hormone replacement, CAH has become a chronic condition, with associated comorbidities and long-term health implications. The aim of treatment is the replacement of mineralocorticoids and glucocorticoids and the normalisation of elevated androgen concentrations. Long-term consequences of the condition and current treatment regimens include unfavourable changes in the cardiovascular risk profile, impaired growth, testicular adrenal rest tumours (TART) in male and subfertility in both male and female patients with CAH. Optimising replacement therapy in patients with CAH remains challenging. On one hand, treatment with supraphysiological doses of glucocorticoids might be required to normalise androgen concentrations and decrease size or presence of TARTs. On the other hand, treatment with supraphysiological doses of glucocorticoids is associated with an increased prevalence of unfavourable cardiovascular and metabolic risk profiles as well as impaired longitudinal growth and gonadal function. Therefore, treatment of children and adults with CAH requires an individualised approach. Careful monitoring for early signs of complications is already warranted during paediatric healthcare provision to prevent and reduce the impact of comorbidities in later life.

Molecular Analysis of CYP21A2 Gene Mutations among Iraqi Patients with Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia is a group of autosomal recessive disorders. The most frequent one is 21-hydroxylase deficiency. Analyzing CYP21A2 gene mutations was so far not reported in Iraq. This work aims to analyze the spectrum and frequency of CYP21A2 mutations among Iraqi CAH patients. Sixty-two children were recruited from the Pediatric Endocrine Consultation Clinic, Children Welfare Teaching Hospital, Baghdad, Iraq, from September 2014 till June 2015. Their ages ranged between one day and 15 years. They presented with salt wasting, simple virilization, or pseudoprecocious puberty. Cytogenetic study was performed for cases with ambiguous genitalia. Molecular analysis of CYP21A2 gene was done using the CAH StripAssay (ViennaLab Diagnostics) for detection of 11 point mutations and >50% of large gene deletions/conversions. Mutations were found in 42 (67.7%) patients; 31 (50%) patients were homozygotes, 9 (14.5%) were heterozygotes, and 2 (3.2%) were compound heterozygotes with 3 mutations, while 20 (32.3%) patients had none of the tested mutations. The most frequently detected mutations were large gene deletions/conversions found in 12 (19.4%) patients, followed by I2Splice and Q318X in 8 (12.9%) patients each, I172N in 5 (8.1%) patients, and V281L in 4 (6.5%) patients. Del 8 bp, P453S, and R483P were each found in one (1.6%) and complex alleles were found in 2 (3.2%). Four point mutations (P30L, Cluster E6, L307 frameshift, and R356W) were not identified in any patient. In conclusion, gene deletions/conversions and 7 point mutations were recorded in varying proportions, the former being the commonest, generally similar to what was reported in regional countries.

Expanded genetic screening panel for the Ashkenazi Jewish population

PURPOSE

Carrier screening programs that identify the presence of known mutations have been effective for reducing the incidence of autosomal recessive conditions in the Ashkenazi Jewish (AJ) population and other populations. Yet, these programs have not realized their full potential. Furthermore, many known autosomal recessive and dominant conditions are not screened for and the molecular basis of other conditions for which screening might be offered is unknown.

METHODS

Through literature review and annotation of full sequenced genomes from healthy individuals, we expanded the list of mutations. Mutations were identified in a sample of 128 fully sequenced AJ genomes that were filtered through clinical databases and curated manually for clinical validity and utility using the American College of Medical Genetics and Genomics scoring (ACMG) system. Other known mutations were identified through literature review.

RESULTS

A panel of 163 mutations was identified for 76 autosomal recessive, 24 autosomal dominant, and 3 X-linked disorders.

CONCLUSION

Screening for a broader range of disorders not only could further reduce the incidence of autosomal recessive disorders but also could offer the benefits of early or presymptomatic diagnosis.Genet Med 18 5, 522-528.

Mutation detection of CYP21A2 gene in nonclassical congenital adrenal hyperplasia patients with premature pubarche

Background:

Congenital adrenal hyperplasia (CAH) due to mutations in the gene encoding 21-hydroxilase is one of common disease with an autosomal recessive form. In this study, our aim is to detect the prevalence of eight common mutations in nonclassical congenital adrenal hyperplasia (NCAH).

Materials and Methods:

A total of 30 patients with clinical and laboratory evidence of NCAH was selected. Gene-specific polymerase chain reaction (PCR) without contamination of pseudogene was carried out, and PCR product of this step was used to amplification-refractory mutation system PCR on eight common mutations in CYP21A2 gene.

Results:

Two heterozygote patients for I2G mutation and six heterozygote patients for Q318X mutation is reported in our study. These mutations associated with the classic form of CAH, and heterozygotes presented with NC symptom, including premature pubarche and hirsutism.

Conclusion:

There are some data about the association of the mutation with the clinical form of CAH including classic (salt-wasting and simple virilizing) and NC form. I2G and Q318X mutations were reported in classic form in homozygote state, but the heterozygote form associated with NC form. CAH diagnosis with NC symptom and with measurement of 17-hydroxyprogestrone as NCAH is not a trusted assessment and require to molecular analysis for accurate diagnosis.

[Genotypes and phenotypes in Uygur children with 21-hydroxylase deficiency in Xinjiang, China]

OBJECTIVE

To investigate gene mutations and the relationship between genotypes and clinical phenotypes in Uygur children with 21-hydroxylase deficiency (21-OHD) in Xinjiang, China.

METHODS

A total of 20 Uygur children with 21-OHD who visited the hospital between October 2013 and October 2014 were enrolled. Full-length direct sequencing and multiplex ligation-dependent probe amplification (MLPA) were used to detect the mutations of CYP21A2 gene, which encoded 21-hydroxylase. According to the type of mutation, the patients with 21-OHD were divided into different groups to analyze the consistency between predicted clinical phenotypes and actual clinical phenotypes.

RESULTS

A total of 9 mutation types were found in the 20 patients, and 8 of them were identified as pathogenic mutations, i.e., Del, conv, I2g, I172N, Cluster E6, 8-bp del, V281L, and R356W. The other mutation is the new mutation occurring in intron 5 (c.648+37A>G), which had not been reported, and its pathological significance remains unknown. Most clinical phenotypes predicted by mutation types had a higher coincidence rate with actual clinical phenotypes (above 67%), and the clinical phenotypes predicted by P30L and V281L had a lower coincidence rate with actual clinical phenotypes (below 33%).

CONCLUSIONS

The genotype of 21-OHD has a good correlation with phenotype, and the clinical phenotype can be predicted by detecting the patient′s genotype. The new mutation (c.648+37A>G) may be related to the pathogenesis of 21-OHD.

High-Dose Hook Effect in 17-Hydroxyprogesterone Assay in a Patient with 21-Hydroxylase Deficiency

Congenital adrenal hyperplasia (CAH) describes a group of disorders characterized by enzyme defects in adrenal steroidogenesis. 21-hydroxylase deficiency (21-OHD) is the most commonly encountered form. The analysis of steroids in pediatric cases requires high-sensitivity assays. A 14-year-old Syrian girl was referred for evaluation of short stature, amenorrhea, and hirsutism. On physical examination, breast development was Tanner stage 1. She had a phallic clitoris with a single urogenital orifice. Laboratory findings revealed primary adrenal deficiency with high androgen levels and low levels of 17-hydroxyprogesterone (17-OHP), (<0.05 ng/mL) and estrogen. This unexpected result led to suspicion of a high-dose hook effect. The measurement was repeated after 1/10 dilution of serum, and a high level of 17-OHP (115.4 ng/mL) was detected with the same test-enzyme-linked immunosorbent assay (ELISA). Simple virilizing form of CAH (21-OHD) was suspected and confirmed with genetic analysis. After initiation of glucocorticoid therapy, breast development was noted along with a decrease in testosterone level and an increase in estrogen level. To our knowledge, this is the first case report of hook effect for 17-OHP immunoassay in a patient with 21-OHD. High-dose hook effect should be suspected in patients with CAH when the test results are incompatible with one another. Additionally, this case demonstrates that a high testosterone level can block aromatase activity and consequently also estrogen production and breast development.

Molecular genetic study of congenital adrenal hyperplasia in Serbia: novel p.Leu129Pro and p.Ser165Pro CYP21A2 gene mutations

PURPOSE

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disease characterized by impaired adrenal steroidogenesis and most often caused by CYP21A2 gene mutations. For the first time, we reported complete spectrum and frequency of CYP21A2 gene mutations in 61 unrelated patients with classical and non-classical CAH from Serbia.

METHODS

Direct DNA sequencing of whole CYP21A2 gene and polymerase chain reaction with sequence-specific primers for detection of CYP21A1P/CYP21A2 chimeras were combined.

RESULTS

We identified 18 different pathogenic alleles-two of them novel. Mutation detection rate was highest in patients with salt-wasting form of CAH (94.7%). The most prevalent mutation was intron 2 splice site mutation, c.290-13A/C>G (18.5%). Other mutation frequencies were: CYP21A1P/CYP21A2 chimeras (13%), p.P30L (13%), p.R356W (11.1%), p.G110fs (7.4%), p.Q318X (4.6%), p.V281L (4.6%), p.I172N (2.8%), p.L307fs (2.8%), p.P453S (1.9%), etc. Mainly, frequencies were similar to those in Slavic populations and bordering countries. However, we found 6.5% of alleles with multiple mutations, frequently including p.P453S. Effects of novel mutations, c.386T>C (p.Leu129Pro) and c.493T>C (p.Ser165Pro), were characterized in silico as deleterious. The effect of well-known mutations on Serbian patients' phenotype was as expected.

CONCLUSIONS

The first comprehensive molecular genetic study of Serbian CAH patients revealed two novel CYP21A2 mutations. This study will enable genetic counseling in our population and contribute to better understanding of molecular landscape of CAH in Europe.

Concurrence of Meningomyelocele and Salt-Wasting Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency

Congenital adrenal hyperplasia (CAH) is a group of inherited defects of cortisol biosynthesis. A case of classical CAH due to 21-hydroxylase deficiency (21-OHD) with early onset of salt waste and concurrence of meningomyelocele (MMC) was presented here. The management of salt-wasting crisis which is complicated by a postrenal dysfunction due to neurogenic bladder was described. Possible reasons of growth retardation in the one-year follow-up period were discussed. A significant regression of the phallus with proper medical treatment was also mentioned.

Prevalence of nonclassic congenital adrenal hyperplasia in Turkish children presenting with premature pubarche, hirsutism, or oligomenorrhoea

Background. Nonclassic congenital adrenal hyperplasia (NCAH), caused by mutations in the gene encoding 21-hydroxylase, is a common autosomal recessive disorder. In the present work, our aim was to determine the prevalence of NCAH presenting as premature pubarche (PP), hirsutism, or polycystic ovarian syndrome (PCOS) and to evaluate the molecular spectrum of CYP21A2 mutations in NCAH patients. Methods. A total of 126 patients (122 females, 4 males) with PP, hirsutism, or PCOS were included in the present study. All patients underwent an ACTH stimulation test. NCAH was considered to be present when the stimulated 17-hydroxyprogesterone plasma level was >10 ng/mL. Results. Seventy-one of the 126 patients (56%) presented with PP, 29 (23%) with PCOS, and 26 (21%) with hirsutism. Six patients (4,7%) were diagnosed with NCAH based on mutational analysis. Four different mutations (Q318X, P30L, V281L, and P453S) were found in six NCAH patients. One patient with NCAH was a compound heterozygote for this mutation, and five were heterozygous. Conclusion. NCAH should be considered as a differential diagnosis in patients presenting with PP, hirsutism, and PCOS, especially in countries in which consanguineous marriages are prevalent.

Diagnosis of diseases of steroid hormone production, metabolism and action

Biochemical tests have been the basis for investigations of disorders affecting steroid hormones. In recent years it has been possible however to study the genes that determine functional enzymes, cofactors, receptors, transcription factors and signaling systems that are involved in the process. Analyses of mutations are available as a diagnostic service for only a few of these genes although research laboratories may be able to provide a service. Both biochemical and genetic research have brought to light new disorders. Some genes for transcription factors involved in the development of the endocrine organs have also been identified and patients with defects in these processes have been found. This paper will review general aspects of adrenal disorders with emphasis on clinical and laboratory findings. As with all endocrine investigations there are few single measurements that provide a definitive answer to a diagnosis. Timing of samples in relation to age, gender and time of day needs to be considered.