RESUMO
Adrenal nodules have been described in patients with 21-hydroxylase deficiency (21OHD). These nodules are usually considered to be ACTH-dependent, as is the commonly seen diffuse cortical hyperplasia. We evaluated the presence and behavior of adrenal nodules in patients with 21OHD. Based upon hormonal status and treatment compliance, the patients were classified into three categories: poor, regular and good control. Out of the 26 patients, eight had the non-classic, four salt-wasting and 14 simple virilizing forms. All patients underwent initial adrenal morphological studies, either by CT or MRI. Those with nodules were reevaluated after 12 months of adequate replacement therapy. Nodules were found in four of eight untreated patients and two of three patients with poor hormonal control, but not in the 15 patients with regular or good control. Adrenal nodules in these six patients demonstrated a considerable size reduction and even disappearance after adequate replacement therapy, showing that these nodules were ACTH-dependent. Thus, six out of 26 patients with 21OHD presented adrenal nodules, which were more frequent in the untreated or poorly-controlled patients, and all regressed in size after adequate therapy.
Assuntos
Glândulas Suprarrenais/patologia , Hiperplasia Suprarrenal Congênita , Hiperplasia Suprarrenal Congênita/patologia , Glucocorticoides/administração & dosagem , Adolescente , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Hormônio Adrenocorticotrópico/farmacologia , Adulto , Criança , Pré-Escolar , Cortisona/administração & dosagem , Cortisona/análogos & derivados , Cortisona/uso terapêutico , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
We determined the frequency of large rearrangements and point mutations in 130 Brazilian patients with 21-hydroxylase deficiency and correlated genotype with phenotype. The frequency of CYP21 deletions was lower (4.4%) than in most of the previous series described, whereas the frequency of large gene conversions was similar to the frequency reported in the literature (6.6%). The most frequent point mutations were I2 splice (41.8% in salt wasting - SW), I172N (32.6% in simple virilizing - SV) and V281L (40.2% in the late onset form - LO). The frequency of the nine most common point mutations was similar to that reported for other countries. The 93 fully genotyped patients were classified into 3 mutation groups based on the degree of enzymatic activity (A<2%, B approximately 2%, C>20%). In group A, 62% of cases presented the SW form; in group B, 96% the SV form, and in group C, 88% the LO form. We diagnosed 80% of the affected alleles after screening for large rearrangements and 15 point mutations. To diagnose these remaining alleles we sequenced the CYP21 gene of one patient with the SV form and identified a heterozygous G-->A transition in codon 424. This mutation leads to a substitution of glycine by serine in a conserved region and was also found in a compound heterozygous state in 4 other patients. The mutation G424S presented a linkage disequilibrium with CYP21P and C4A gene deletions and HLA DR17, suggesting a probable founder effect. Search for the G424S mutation in other populations will reveal if it is restricted to the Brazilian patients or if it has a wider ethnic distribution.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Alelos , Southern Blotting , Brasil , Feminino , Frequência do Gene , Genes/genética , Genótipo , Humanos , Masculino , Fenótipo , Mutação Puntual , Reação em Cadeia da PolimeraseRESUMO
OBJECTIVE: The diagnosis of the nonclassical form of 21-hydroxylase (NC-21OH) deficiency, established before molecular studies, is based on basal 17OH-progesterone (17OH-P) values > 15 nmol/l or ACTH-stimulated 17OH-P values > 30 nmol/l. This disease is caused by mutations in the structural gene that can be grouped into three categories: A, B and C, according to the predicted level of enzymatic activity. So, the genotype of the nonclassical form is a combination of mutations that cause moderate impairment of enzymatic activity in one allele and mutations which cause total (A), severe (B: 3%) or moderate (C: 20-60%) impairment of enzymatic activity in the other allele. DESIGN: We analysed the influence of the different genotypes on 17OH-P levels in 58 patients with the nonclassical form of 21OH deficiency. RESULTS: After screening for 18 mutations through Southern blotting, allele-specific polymerase chain reaction (PCR) and enzyme restriction, mutations were identified in 73% of the alleles. Patients with mutations identified in both alleles were divided into groups A/C (n = 18), B/C (n = 3) and C/C (n = 15). The basal and ACTH-stimulated 17OH-P levels in patients with A/C genotype ranged from 1.2 to 153 and 72-363 nmol/l, and in C/C genotype ranged from 0.9 to 72 and 51-363 nmol/l, respectively (P < 0.05 for stimulated levels). The lowest value of ACTH-stimulated 17OH-P levels in fully genotyped patients was 51 nmol/l. Patients with the A/C genotype presented androgen excess symptoms earlier than patients with the C/C genotype. CONCLUSIONS: These data suggest an influence of genotype on phenotype and on 17OH-P levels. The high frequency of unidentified mutant alleles in nonclassical 21-hydroxylase deficiency suggests that ACTH-stimulated values of 17OH-P between 30 and 51 nmol/l have overestimated this diagnosis. Genotyping more patients with nonclassical 21-hydroxylase deficiency will help to redefine the cut-off value for ACTH-stimulated 17OH-P for correct diagnosis of this disease.
Assuntos
17-alfa-Hidroxiprogesterona/sangue , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/genética , Esteroide 21-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/diagnóstico , Hormônio Adrenocorticotrópico , Adulto , Alelos , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Mutação , Estatísticas não ParamétricasRESUMO
A previous screening of 17 mutations in 130 Brazilian patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency did not identify mutations in 20% of the alleles. To diagnose these alleles we sequenced the entire CYP21 gene of one Mulatto patient with the simple virilizing form, who had only the R356W mutation in a heterozygous state. We identified a heterozygous G-A transition in codon 424. This mutation leads to a substitution of glycine by serine in a conserved region where glycine is conserved in at least 4 species. This novel mutation eliminates 1 of the restriction sites of the BanI enzyme, which made its screening possible for the whole series. The G424S mutation was found in a compound heterozygous state in 5 families; 4 presented the simple virilizing form, and 1 presented the nonclassical form. Interestingly, 3 of 5 families have a Mulatto origin. This mutation was not identified in 118 CYP21 alleles of normal individuals, ruling out the possibility of a polymorphism, or in 80 pseudogenes, indicating a casual mutagenic event and not a microconversion event. All patients with the G424S mutation presented CYP21P and C4A gene deletions and human leukocyte antigen DR17 on the same haplotype, suggesting a linkage disequilibrium and a probable founder effect. Search for the G424S mutation in other populations will reveal whether it is restricted to the Brazilian patients or if it has a wider ethnic distribution.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Mutação de Sentido Incorreto , Esteroide 21-Hidroxilase/genética , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Reação em Cadeia da PolimeraseRESUMO
The frequency of large mutations was determined in 131 Brazilian patients with different clinical forms of 21-hydroxylase deficiency, belonging to 116 families. DNA samples were examined by Southern blotting hybridization with genomic CYP21 and C4cDNA probes after Taql and Bg/II restriction. Large gene conversions were found in 6.6% and CYP21B deletions in 4.4% of the alleles. The breakpoint in these hybrid genes occurred after exon 3 in 92% of the alleles. All rearrangements involving CYP21B gene occurred in the heterozygous form, except in a patient with simple virilizing form who presented homozygous CYP21B deletion. Our data showed that in these Brazilian patients, CYP21B deletions were less frequent than in most of the large series previously reported.
Assuntos
Hiperplasia Suprarrenal Congênita/genética , Deleção de Genes , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/enzimologia , Adulto , Alelos , Southern Blotting , Brasil , Criança , Feminino , Humanos , Masculino , Mutação , Reação em Cadeia da Polimerase/métodos , Mapeamento por RestriçãoRESUMO
The aim of our study was to determine, by allele-specific PCR, the frequency of point mutations in 130 Brazilian patients with the classical and nonclassical forms of 21-hydroxylase deficiency and to correlate genotype with phenotype. The most frequent mutations were 12 splice (41.8% in salt wasting), I172N (32.6% in simple virilizing), and V281L (40.2% in late onset form). The frequency of the 9 most common point mutations was similar to that reported for other countries, except for Del 8 nt and Cluster, which were less frequent in the classical form. Rarer mutations such as P453S, G291S, I7 splice, W405X, R483P, and R483-->frameshift were rarely found or were absent. The 93 fully genotyped patients were classified into 3 mutation groups, based on the degree of enzymatic activity (group A, <2%; group B, approximately 2%, and group C, >18%). In group A, 62% of the cases presented the salt wasting form; in group B, 96% the simple virilizing form; and in group C, 88% the late onset form. We diagnosed 80% of the affected alleles after screening for large rearrangements and 15 point mutations. The absence of previously described mutations in 20% of the affected alleles suggests the presence of new mutations in our population.
Assuntos
Hiperplasia Suprarrenal Congênita , Hiperplasia Suprarrenal Congênita/genética , Alelos , Brasil , Estudos de Coortes , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Fenótipo , Mutação Puntual/genética , Esteroide 21-Hidroxilase/genéticaRESUMO
PURPOSE: We reviewed clinical and laboratory findings in 6 male and 32 female patients with functional adrenocortical neoplasms, and compared pediatric and adult data. MATERIALS AND METHODS: Hormonal measurements were performed by radioimmunoassay, histological analysis was based on Weiss criteria and staging was done according to previously established guidelines. RESULTS: Children had a higher incidence of virilization (72%), whereas in adults the predominant feature was Cushing's syndrome (60%). A high testosterone level was the most common finding in adults and children with virilization followed by high dehydroepiandrosterone sulfate, androstenedione and dehydroepiandrosterone levels. High 11-deoxycortisol levels were frequently associated with tumor recurrence. Cortisol suppression after dexamethasone was altered in 93% of patients with virilization and no clinical features, suggesting autonomous cortisol secretion. CONCLUSIONS: No statistically significant relation was noted between tumor weight and prognosis but there was a negative correlation between patient age and prognosis since children had a more favorable followup than adults. Mixed features in both groups resulted in the worst prognosis. A Weiss criteria grade IV or greater correlated well with a poor prognosis in adults but not children, while staging was more reliable in children.
Assuntos
Neoplasias do Córtex Suprarrenal , Adolescente , Neoplasias do Córtex Suprarrenal/sangue , Neoplasias do Córtex Suprarrenal/complicações , Neoplasias do Córtex Suprarrenal/patologia , Adulto , Criança , Pré-Escolar , Síndrome de Cushing/sangue , Síndrome de Cushing/etiologia , Feminino , Seguimentos , Hormônios Esteroides Gonadais/sangue , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Virilismo/sangue , Virilismo/etiologiaRESUMO
Zinc plays a very important role in animal and human metabolism. Nowadays, it is one of the most extensively studied trace element, since its sphere of action has been demonstrated to be very broad. From the biochemical standpoint, it controls more than 300 different enzymes, many of them involved with intermediary metabolism, DNA and RNA synthesis, gene expression, and immunocompetence. It also plays a significant role in hormonal homeostasis, since it can interact with almost all hormones. Zn2+ is closely related to the thyroid and steroid hormones, insulin, parathormone, and pituitary hormones, particularly prolactin (PRL). Zn2+ can inhibit PRL secretion within a range of physiologically and pharmacologically relevant concentrations. This property has raised the possibility of clinical applications of zinc. In this article, we review the literature on the subject in an attempt to provide a comprehensible general view.
Assuntos
Hipófise/metabolismo , Prolactina/biossíntese , Zinco/farmacologia , Animais , Cálcio/metabolismo , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Calmodulina/metabolismo , Enzimas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Técnicas In Vitro , Hipófise/efeitos dos fármacos , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/patologia , Prolactina/metabolismo , Prolactinoma/tratamento farmacológico , Prolactinoma/patologia , Zinco/fisiologia , Dedos de Zinco/fisiologiaRESUMO
The response of plasma prolactin (PRL) to oral administration of increasing doses of zinc (25.0, 37.5 and 50.0 mg) was studied in 17 normal adult men and women. Blood samples were collected at 10 and 30-min intervals over a period of 120 min after two basal times (-30 and 0 min). PRL concentrations significantly fell below basal levels in all subjects in response to the increase in plasma zinc levels, as compared to the controls. These results suggest that acute hyperzincemia can inhibit basal PRL secretion in normal individuals.
Assuntos
Prolactina/metabolismo , Zinco/farmacologia , Adulto , Feminino , Humanos , Masculino , Radioimunoensaio , Zinco/sangueRESUMO
The authors studied 8 patients (4 males and 4 females) with Cushing's syndrome due to ectopic ACTH secretion. Chronological age ranged from 15 to 45 years and duration of the disease ranged from 3 to 48 months. All patients presented typical signs of Cushing's syndrome, blood hypertension, and four of them had hyperpigmentation of the skin. Five patients had fasting hyperglycemia and all patients but one had serum hypokalemia (serum K = 2.2 to 3.9mEq/l). The circadian rhythm of cortisol was absent in all patients and basal cortisol levels were elevated in all patients but one. Basal ACTH levels evaluated in 7 patients were elevated in 6 (29 to 1050 pg/ml-MRC). One patient presented normal depression of urinary 17-OH after two days of dexamethasone and normal increase of urinary 17-OH and serum 11-dexycortisol after methyrapone. Four patients had carcinoid tumor (3 thymic and 1 bronchial), two had pancreatic islets cell tumors, one had bilateral pheochromocytoma and medular carcinoma of the thyroid, and one had oat cell carcinoma of the lung and medular carcinoma of the thyroid. Thoracic X-rays identified the ectopic ACTH secretion tumor in four cases, all confirmed by CT scan. Abdominal CT showed a difuse enlargement of the adrenals in seven cases and bilateral nodules in one case (pheochromocytomas). Six patients died within 3 years of the diagnosis. The authors concluded that clinical and hormonal findings could mislead the findings of ACTH ectopic secretion and Cushing's disease, and suggest that thoracic X-rays and CT scans of the skull, thorax, and abdome should be done in all cases of Cushing's syndrome.