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Fibrocystic breast changes
Paget disease of the breast
Intrauterine growth restriction
Pelvic inflammatory disease
Gestational trophoblastic disease
Germ cell ovarian tumor
Polycystic ovary syndrome
Premature ovarian failure
Sex cord-gonadal stromal tumor
Surface epithelial-stromal tumor
Congenital cytomegalovirus (NORD)
Congenital rubella syndrome
Neonatal herpes simplex
Preeclampsia & eclampsia
Female sexual interest and arousal disorder
Genito-pelvic pain and penetration disorder
Fetal alcohol syndrome
Fetal hydantoin syndrome
Androgen insensitivity syndrome
Hypospadias and epispadias
Benign prostatic hyperplasia
Male hypoactive sexual desire disorder
Amenorrhea: Pathology review
Benign breast conditions: Pathology review
Breast cancer: Pathology review
Cervical cancer: Pathology review
Complications during pregnancy: Pathology review
Congenital TORCH infections: Pathology review
Disorders of sex chromosomes: Pathology review
Disorders of sexual development and sex hormones: Pathology review
HIV and AIDS: Pathology review
Ovarian cysts and tumors: Pathology review
Penile conditions: Pathology review
Prostate disorders and cancer: Pathology review
Sexually transmitted infections: Vaginitis and cervicitis: Pathology review
Sexually transmitted infections: Warts and ulcers: Pathology review
Testicular and scrotal conditions: Pathology review
Testicular tumors: Pathology review
Uterine disorders: Pathology review
Vaginal and vulvar disorders: Pathology review
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Living with Klinefelter Syndrome
Testicular Disorders & Cancer
Klinefelter syndrome p. 657
chromosome association p. 62
gynecomastia p. 669
testicular tumors p. 672
Klinefelter syndrome, named after Dr. Harry Klinefelter who first identified it, is a chromosomal problem where a person with an XY genotype - biologically a male - inherits at least one extra X-chromosome, and sometimes a few extra ones.
Having an extra X chromosome makes the testicular cells generate less testosterone, which is the hormone responsible for primary sex characteristics like development of the sex organs as well as secondary sex characteristics like height and body shape.
It’s worth mentioning up front, that we’re using the term male here, rather than boy or man, to talk about the biological category of a person’s sex rather than a person’s gender identity.
Now, in puberty, in both males and females, the hypothalamus starts to release more gonadotropin releasing hormone, which gets the pituitary gland to release luteinizing hormone and follicle-stimulating hormone.
In males, these hormones affect the Leydig cells and the Sertoli cells.
The Leydig cells are in the interstitium of the testes, and in response to luteinizing hormone they convert cholesterol into testosterone.
The testosterone along with follicle-stimulating hormone, then stimulate Sertoli cells in the seminiferous tubules of the testes to make more sperm.
To main balance or homeostasis, testosterone reduces gonadotropin releasing hormone and luteinizing hormone, and Sertoli cells release the hormone inhibin which inhibits release of follicle-stimulating hormone.
In Klinefelter syndrome, this hormone balance is altered.
The extra X-chromosome interrupts the normal function of the Sertoli and Leydig cells.
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