Chapter 181. Pathology Associated With The Adrenal Gland - Review of Medical Embryology Book

IN ANENCEPHALICS, the anterior pituitary is often only slightly affected. However, since the hypothalamus is missing, the neurohypophysis contains no neurosecretion, and without this, ACTH is not secreted (this is the case even in the presence of an intact anterior pituitary lobe)

It should be noted that anencephaly has little effect before month 5 of fetal life since development of the adrenal up to this point appears to be autonomous
After month 5, development of the fetal cortex cannot occur without ACTH, thus, in the anencephalic, there is an involution of the adrenal cortex leading to agenesis or hypoplasia

THIS CONDITION PRODUCES late fetal masculinization of the female genital tract
THE MOST COMMON CAUSE of this condition is the adrenogenital syndrome, resulting from congenital virilizing adrenal hyperplasia

There is no ovarian abnormality
Excessive adrenal production of androgens causes masculinization of the external genitalia varying from clitoral enlargement to almost male genitalia
Clitoral hypertrophy is common, as are partial fusion of the labia majora and a persistent urogenital sinus
Rarely, fusion of the labioscrotal and urogenital folds is so complete that the urethra passes through the penis and the infants are raised as males
Prompt recognition and treatment of the associated adrenal inbalance are essential

Transmission of autosomal recessive, and the genotype of the affected person is actually female (XX)

THIS CONDITION INTHE MALE causes hypermasculinization with precocious virilization

Ectopic adrenal glands: the adrenal tissue is found beneath the kidney capsule
Accessory cortical tissue: this accessory tissue is most often associated with the definitive adrenal gland itself, but it may be found retroperitoneally on the posterior abdominal wall or in the pelvis. Medullary tissue is not usually present
Agenesis of the adrenal: unilateral agenesis of the gland is almost always associated with agenesis of the kidney on the same side

BOUND UP WITH the failure of the entire nephrogenic ridge to form, early in week 4

Congenital adrenal hypoplasia usually manifests itself shortly after birth with many of the symptoms of Addison's disease
Fusion of the suprarenal glands: seen when kidneys are also fused across the midline
V Cushing's syndrome: fully developed Cushing's syndrome has not been observed as yet, but hirsuitism and pubic hair at birth have been described with clitoral enlargement

CUSHING'S SYNDROME has been described at about 17 months of age along with adrenogenital syndromes
SOME CASES have been described with symptoms appearing within weeks after birth, suggesting a prenatal disturbance
IT IS CAUSED BY ADRENAL HYPERPLASIA or tumor which produces excessive amounts of hormones from the cortex. Clinical features vary, depending on the type of adrenal hormones being produced in excess