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Unit 1 ID+LC > Male Pathophys > Flashcards

Flashcards in Male Pathophys Deck (25)
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a clinical syndrome that results from failure of testes to produce phys. lvls of T and the nl # of spermatozoa due to disruption of 1/m lvls of the HPG axis


Sexual signs of hypogonadism

1. diminished libido
2. erectile dysfxn
3. DIff achieving orgasm
4. decreased performance

*but can present this way even if indiv doesnt have hypogonadism


CLue for exogenous androgen exposure

undetectable gonadotropins


Pathophys of testosterone deficiency: hypothalamic dysfxn

see slide


Genetic causes of GnRH deficiency

Kallman syndrome

Mut in KAL1 at pituitary
- Presents with Anosmia: can't smell


Acquired Central Hypogonadism

Low - low nl LH + FSH
Low T

1. GnRH pulse generator defect due to:
- stress
- severe illness
-abnl weight loss

2. Narcotics:
- opioids/marijuana: wipe out pulse generator

3. Glucocorticoids:
- steroid injxn: suppresses adrenal axis and T

4. Supplements:
- prohormones
- anabolic steroids: cause undetectable LH/FSH


nl T lvls for adult

240-800 ng/dl

Young men: 550 ng/dl
- more SHGB makes higher total T lvls
Older men:
240 ng/dl
- Less SHGB makes a lower total T lvls


Causes of ED

1. Vascular
2. Neurogenic
3. Hormonal
4. Iatrogenic


Obstructive sleep apnea

1. Hypoxia --> high cortisol and catacholamines -->
Insulin resistance + metabolic syndrome
2. SNoring, apnea
3. Fatigue daytime somnolence
4. ED: decreased NO in cavernosal muscle

T worsens untreated OSA
TX: CPAP, lifestyle intervention


Different causes of Pituitary hypogonadism
- Low LH + FSH
Low T

1. Prolactinoma: increases Prl

2. Tumors/Mass effects
- craniopharyngioma
- pituitary tumor
- mets

3. Infiltrative disorders: hemachromatosis (iron deposits selectively in gonadotropes)

4. Inflammatory: lymphocytic hypophysitis due to new drug IPI when treating melanoma


Loss of inhibin


*inhibin regulates FSH
- FSH + LH are usually the same at ~10-12


First sign of puberty in boy

testicular enlargement


Pathophys of T deficiency: testicular dysfxn

see slide


Hypergonadotropic hypogonadism

high FSH
high/low LH
Low T

- Different congenital causes

1. Congenital: anorchia, vanishing testes syndrome
- high GnRH is induced to try to stimulate failing gonad

2. Klinefelter's syndrome
- failing testes
- no sertoli, intact leydig
- low inhibin B lvls
- delayed puberty
- genecomastia
- risk for DVT/PE


Causes of acquired hypergonadotropic hypogonadism

high FSH
high/low LH
Low T

1. Trauma or torsion
- testes dies --> sertoli dies --> loss of inhibin --> rise in FSH
2. Mumps orchitis
3. Alcohol: direct testicular toxin
4. Diabetes
5. Radiation/chemotherapy
6. Autoimmune testicular failure: check TSH, glucose, B12, Vit D
7. *Pituitary tumor:
- High FSH:LH, low T


Gonadotrope pituitary tumor
:aka FSH/LH secreting tumor

glycoprotein tumor of the pituitary that overproduces abnl LH + FSH, while at the same time compresses the pituitary and prevent release of real LH+FSH --> T lvls end up low

Labs: high FSH/LH, low T

Hx: HA, lateral visual disturbances, ED

Exam: visual fields, sx of hypogonadism, softening of testes

Tx: surgery


What should we do in pts with low-nl T lvls?

1. diet
2. lifestyle
3. successful weight loss
- increase T lvls
- Improve OSA
- Improve cardiovascular and metabolic fitness
- Improve ED

DO NOt dz hypogonadism right away


Cardiac Risks of T therapy

Increased cardiac events
- esp in elderly men
- ACS, MI, Syncope, HTN, arrhythmia, edema, CHF

*Too low or Too high T has adverse effects


Potential risk of T therapy

1. Stim prostate growth in previously undiagnosed prostate cancer
2. risk of bladder outlet symptoms due to increase in prostate volume
3. Edema in pts with pre-existing cardiac, renal, hepatic disease
4. Gynecomastia (converted to E)
5. Erythrocytosis
6. PPT / worsening of sleep apnea
7. increased CV risk


Things that can cause hypogonadotropic hypogonadism: Low GnRH, LH, FSH, T

1. genetic - rare
- Kallman syndrome

2. Acquired:
- narcs, GC, hemochromatosis, tumor, XRT, stress, illness


Things that can cause high FSH, LH, low testosterone

1. Primary testicular failure
2. Gonadotrope pituitary tumor


DHT acts specifically on what?

External genitalia and prostate


what is the gonadal peptide that inhibits FSH in males and acts locally in the testes?

Inhibin B (alpha and betaB)
- not betaA


Hypogonadotropic hypogonadism can be due to:

1. Congenital
- GnRH neurons fails to migrate to hypothalamus (Kallman's syndrome if anosmia is also included)
- neurons migrate with olfactory neurons in utero

*intact hardware, but software program is missing

2. Acquired deficits of GnRH or LH and FSH



Most common pituitary tumor
- Makes Prl which blocks GnRH induced LH and FSH signal
- Acquired cause of Hypogonadotropic hypogonadism