In a girl with sexual infantilism and defective smell sensation which of the following is the likely diagnosis transmitted by sex chromosome?
Ans. a (Kallman's syndrome) (Ref. H -18th/Ch. 339).Kallmann syndrome results from defective hypothalamic GnRH synthesis and is associated with anosmia or hyposmia due to olfactory bulb agenesis or hypoplasia. The syndrome also may be associated with color blindness, optic atrophy, nerve deafness, cleft palate, renal abnormalities, cryptorchidism, and neurologic abnormalities such as mirror movements. Defects in the X-linked KAL gene impair embryonic migration of GnRH neurons from the hypothalamic olfactory placode to the hypothalamus. Autosomal recessive (i.e., GPR54, K1SS1) and dominant (i.e., FGFR1) modes of transmission have been described. Males present with delayed puberty and pronounced hypogonadal features, including micropenis, probably the result of low testosterone levels during infancy. Females present with primary amenorrhea and failure of secondary sexual development.Kallmann syndrome and other causes of congenital GnRH deficiency are characterized by low LH and FSH levels and low concentrations of sex steroids (testosterone or estradiol).Long-term Rx of men with hCG or testosterone restores pubertal development and secondary sex characteristics; women can be treated with cyclic estrogen and progestin. Fertility also may be restored by the administration of gonadotropins or by using a infusion pump to deliver subcutaneous, pulsatile GnRH.Kallmann's syndromeis an X-linked disorder characterized by hypogonadotropic hypogonadism, which is associated with anosmia. It more commonly affects men than women.McCune-Albright syndromeis characterized by patchy cutaneous hyperpigmentation, polyostotic fibrous dysplasia, and several endocrine disorders including toxic multinodular goiter.Testicular feminization syndrome (complete androgen insensitivity syndrome)A genetic disorder that makes XY fetuses insensitive to androgens (male hormones)Instead, they are born looking externally like normal girls. Internally, there is a short blind-pouch vagina and no uterus, fallopian tubes or ovaries. There are testes in the abdomen or the inguinal canal.Mayer-Rokitansky-Kuster- Hauster syndromeCongenital absence of the uterus is usually associated with absent vagina. Presents with primary amenorrhoea, 46 XX karyotype and normal ovarian function and secondary sexual development. Differential diagnosis - androgen insensitivity syndrome.
Kallman's syndrome
Rokitansky-Kuster-Hauster syndrome
Androgen insensitivity syndrome
McCune-Albright syndrome
Genital Differentiation