11β-hydroxylase deficiency overview: Difference between revisions
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Patients with 11β-hydroxylase deficiency usually appear healthy. Physical examination of patients with 11β-hydroxylase deficiency is usually remarkable for [[Gynaecomastia|gynecomastia]], [[hyperpigmentation]], [[hypertension]], and [[ambiguous genitalia]]. | Patients with 11β-hydroxylase deficiency usually appear healthy. Physical examination of patients with 11β-hydroxylase deficiency is usually remarkable for [[Gynaecomastia|gynecomastia]], [[hyperpigmentation]], [[hypertension]], and [[ambiguous genitalia]]. | ||
==Laboratory Findings== | ==Laboratory Findings== | ||
Laboratory findings consistent with the diagnosis of | Laboratory findings consistent with the diagnosis of 11β-hydroxylase deficiency include elevated [[17-Hydroxyprogesterone|17-hydroxyprogesterone]], elevated [[androstenedione]], elevated urinary 17-ketosteroids, and decreased [[renin]]. | ||
==CT== | ==CT== | ||
On abdominal [[CT scan]], congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the [[adrenal glands]]. | On abdominal [[CT scan]], congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the [[adrenal glands]]. | ||
Revision as of 16:03, 3 August 2017
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11β-hydroxylase deficiency Microchapters |
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Differentiating 11β-hydroxylase deficiency from other Diseases |
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Diagnosis |
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Treatment |
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Case Studies |
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11β-hydroxylase deficiency overview On the Web |
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American Roentgen Ray Society Images of 11β-hydroxylase deficiency overview |
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Directions to Hospitals Treating Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency |
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Risk calculators and risk factors for 11β-hydroxylase deficiency overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ammu Susheela, M.D. [2]
Overview
Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency arises due to a defect in the gene encoding the enzyme steroid 11β-hydroxylase which mediates the final step of cortisol synthesis in the adrenal. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency was first described by Dr. Walter Eberlein and Dr. Alfred M. Bongiovanni, American physicians, in 1956 based on the study they conducted on accumulated steroids. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency may be classified according to clinical presentation into 2 subtypes: classic form and the non-classic form. Mutations in the CYP11B1 gene cause congenital adrenal hyperplasia due to 11β-hydroxylase deficiency. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency must be differentiated from other diseases that cause clinical features, such as adrenal crisis, conn syndrome, gastric outlet obstruction, congenital adrenal hyperplasia due to 17-hydroxylase deficiency, congenital adrenal hyperplasia due to 21-hydroxylase deficiency, hypertension, hypokalemia, hypomagnesemia, infertility, polycystic ovarian syndrome, malignant hypertension, Stein-Leventhal syndrome, and viral gastroenteritis. The prevalence of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is approximately 1 per 100,000 individuals the United States. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency affects male and female equally. The most potent risk factor in the development of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is the presence of family history of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency. Prenatal screening for congenital adrenal hyperplasia due to 11β-hydroxylase deficiency by injection a dose of 11-deoxycortisol into the amniotic fluid is recommended for patients with congenital adrenal hyperplasia due to 11β-hydroxylase deficiency. If left untreated, patients with congenital adrenal hyperplasia due to 11β-hydroxylase deficiency may progress to develop malignant hypertension. Common complications of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency include muscle weakness, metabolic alkalosis, and azoospermia. Prognosis is generally good with treatment. On abdominal CT scan, congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the adrenal glands. On abdominal MRI, congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the adrenal glands. Immunohistochemical staining of the adrenal gland may be used for the diagnosis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency and it demonstrates hyperplasia, poorly defined zonation, and intermingling of the chromaffin and cortical cells. The mainstay of therapy for congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is glucocorticoid therapy. The predominant therapy for ambiguous genitalia in congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is the surgical correction.
Historical Perspective
11β-hydroxylase deficiency was first described by Dr. Walter Eberlein and Dr. Alfred M. Bongiovanni, American physicians, in 1956 based on the study they conducted on accumulated steroids. In 1999, White was the first to discover the association between homozygous mutation in the CYP11B1 gene and development of 11β-hydroxylase deficiency.
Classification
11β-hydroxylase deficiency may be classified according to the clinical presentation into 2 subtypes: the classic form and the non-classic form of the 11β-hydroxylase deficiency.
Pathophysiology
11β-Hydroxylase deficiency is a type of congenital adrenal hyperplasia resulting from a defect in CYP11B1 on chromosome 8. CYP11B1 gene encodes an enzyme called 11β-hydroxylase in the path of steroid biosynthesis. This enzyme is located in the zona fasciculate, and converts 11-deoxycortisol to cortisol and 11-deoxycorticosterone. Lack of 11β-hydroxylase enzyme in different amounts results in accumulation of 11-deoxycortisol, and decrease amounts of cortisol and 11-deoxycorticosterone. There is an elevation of adrenocorticotropic hormone results in overproduction of 11-deoxycorticosterone (DOC) by mid-childhood. 11-deoxycorticosterone is a weak mineralocorticoid, but because of high amounts in this disease can cause mineralocorticoid excess effects such as salt retention, volume expansion, and hypertension. Non-classic forms mostly doesn't have verifiable mutations and mild 11β-hydroxylase deficiency is currently considered a very rare cause of hirsutism and infertility.
Causes
Mutations in the CYP11B1 gene cause 11β-hydroxylase deficiency, classic type. The responsible mutation in non-classic type is unknown.
Differentiating Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency from other Diseases
11β-hydroxylase deficiency must be differentiated from diseases that cause ambiguous genitalia such as 21-hydroxylase deficiency, 17 alpha-hydroxylase deficiency, 3 beta-hydroxysteroid dehydrogenase deficiency and Gestational hyperandrogenism.
Epidemiology and Demographics
The prevalence of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is approximately 1 per 100,000 individuals the United States. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency affects male and female equally. Congenital adrenal hyperplasia due to 11β-hydroxylase deficiency usually affects individuals of the Jewish race.
Risk Factors
The most potent risk factor in the development of 11β-hydroxylase deficiency is the presence of family history of 11β-hydroxylase deficiency..
Screening
There is insufficient evidence to recommend routine screening for 11β-hydroxylase deficiency.
Natural history, Complications and Prognosis
If left untreated, patients with 11β-hydroxylase deficiency may progress to develop malignant hypertension. Common complications of 11β-hydroxylase deficiency include muscle weakness, metabolic alkalosis, menstrual irregularities in women, acne, hirsutism, and infertility. Prognosis is generally good with treatment.
History and Symptoms
Symptoms of 11β-hydroxylase deficiency include female patients with ambiguous genitalia, clitoromegaly, labial fusion, hirsutism, menstrual irregularities, aggressive behavior; male patients present with increased penile size in newborns, acne. Children who are not diagnosed at birth, may present with premature adrenarche, adult body odor, axillary and pubic hair development, faster growth and bone age in premature adrenarche.
Physical Examination
Patients with 11β-hydroxylase deficiency usually appear healthy. Physical examination of patients with 11β-hydroxylase deficiency is usually remarkable for gynecomastia, hyperpigmentation, hypertension, and ambiguous genitalia.
Laboratory Findings
Laboratory findings consistent with the diagnosis of 11β-hydroxylase deficiency include elevated 17-hydroxyprogesterone, elevated androstenedione, elevated urinary 17-ketosteroids, and decreased renin.
CT
On abdominal CT scan, congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the adrenal glands.
MRI
On abdominal MRI, congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is characterized by bilateral symmetric enlargement of the adrenal glands.
Ultrasound
Ultrasound may be helpful in the diagnosis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency. Findings on ultrasound suggestive of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency include testicular masses, adnexal structures, and gonadal abnormalities.
Other Imaging Findings
Immunohistochemical staining of the adrenal gland may be used for the diagnosis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency and it demonstrates hyperplasia, poorly defined zonation, and intermingling of the chromaffin and cortical cells.
Other Diagnostic Studies
Immunohistochemical staining of the adrenal gland may be used for the diagnosis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency and it demonstrates hyperplasia, poorly defined zonation, and intermingling of the chromaffin and cortical cells.
Medical Therapy
The mainstay of therapy for congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is glucocorticoid therapy.
Surgery
The predominant therapy for ambiguous genitalia in congenital adrenal hyperplasia due to 11β-hydroxylase deficiency is the surgical correction.
Prevention
Prenatal diagnosis of 11-beta-hydroxylase deficiency is conducted to prevent the complication of the disease in future life and treated with prenatal dexamethasone treatment.