21-hydroxylase deficiency history and symptoms: Difference between revisions
No edit summary |
No edit summary |
||
| Line 9: | Line 9: | ||
====Virilization of female infants==== | ====Virilization of female infants==== | ||
Virilization of genetically female (XX) infants usually produces obvious [[ambiguous genitalia|genital ambiguity]]. Inside the pelvis, the [[ovary|ovaries]] are normal and since they have not been exposed to testicular [[antimullerian hormone]], the [[uterus]], [[fallopian tube]]s, upper [[vagina]], and other mullerian structures are normally formed as well. However, the high levels of testosterone in the blood can enlarge the | Virilization of genetically female (XX) infants usually produces obvious [[ambiguous genitalia|genital ambiguity]]. Inside the pelvis, the [[ovary|ovaries]] are normal and since they have not been exposed to testicular [[antimullerian hormone]], the [[uterus]], [[fallopian tube]]s, upper [[vagina]], and other mullerian structures are normally formed as well. However, the high levels of testosterone in the blood can enlarge the phallus, partially or completely close the vaginal opening, enclose the [[urethra]]l groove so that it opens at the base of the phallus, on the shaft or even at the tip like a boy. Testosterone can cause the [[labia]]l skin to become as thin and rugated as a [[scrotum]], but cannot produce palpable gonads (i.e., testes) in the folds. | ||
====Salt-wasting crises in infancy==== | ====Salt-wasting crises in infancy==== | ||
Revision as of 12:58, 4 September 2015
|
Congenital adrenal hyperplasia due to 21-hydroxylase deficiency Microchapters |
|
Differentiating Congenital adrenal hyperplasia due to 21-hydroxylase deficiency from other Diseases |
|---|
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
21-hydroxylase deficiency history and symptoms On the Web |
|
American Roentgen Ray Society Images of 21-hydroxylase deficiency history and symptoms |
|
Directions to Hospitals Treating Congenital adrenal hyperplasia due to 21-hydroxylase deficiency |
|
Risk calculators and risk factors for 21-hydroxylase deficiency history and symptoms |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]
Overview
History and Symptoms
Early-onset: Severe 21-hydroxylase deficient CAH
The two most serious neonatal consequences of 21-hydroxylase deficiency occur when there is minimal measurable hydroxylase activity from prenatal life: severe virilization of female infants and life-threatening salt-wasting crises in the first month of life for XX and XY infants alike.
Virilization of female infants
Virilization of genetically female (XX) infants usually produces obvious genital ambiguity. Inside the pelvis, the ovaries are normal and since they have not been exposed to testicular antimullerian hormone, the uterus, fallopian tubes, upper vagina, and other mullerian structures are normally formed as well. However, the high levels of testosterone in the blood can enlarge the phallus, partially or completely close the vaginal opening, enclose the urethral groove so that it opens at the base of the phallus, on the shaft or even at the tip like a boy. Testosterone can cause the labial skin to become as thin and rugated as a scrotum, but cannot produce palpable gonads (i.e., testes) in the folds.
Salt-wasting crises in infancy
The excessive amounts of adrenal testosterone produce little effect on the genitalia of male infants with severe CAH. If a male infant with CAH is not detected by newborn screening, he will appear healthy and normal and be quickly discharged home to his family.
However, the lack of aldosterone results in a high rate of sodium loss in the urine. Urinary sodium concentrations may exceed 50 mEq/L. With this rate of salt loss, the infant cannot maintain blood volume, and hyponatremic dehydration begins to develop by the end of the first week of life. Potassium and acid excretion are also impaired when mineralocorticoid activity is deficient, and hyperkalemia and metabolic acidosis gradually develop. Ability to maintain circulation is further limited by the effect of cortisol deficiency. The early symptoms are spitting and poor weight gain, but most infants with severe CAH develop vomiting, severe dehydration, and circulatory collapse (shock) by the second or third week of life.
Childhood onset (simple virilizing) CAH
Mutations that result in some residual 21-hydroxylase activity cause milder disease, traditionally termed simple virilizing CAH (SVCAH). In these children the mineralocorticoid deficiency is insignificant and salt-wasting does not occur. The androgen excess is mild enough that virilization is not apparent or goes unrecognized at birth and in early childhood. However, androgen levels are above normal and slowly rise during childhood, producing noticeable effects between 2 and 9 years of age.
Late onset (nonclassical) CAH
Other alleles result in even milder degrees of hyperandrogenism that may not even cause problems in males and may not be recognized until adolescence or later in females. Mild androgen effects in young women may include hirsutism, acne, or anovulation (which in turn can cause infertility). Testosterone levels in these woman may be mildly elevated, or simply above average.