- Failure of pituitary/hypothalamus to produce adequate LH to stimulate testes
- Pituitary/hypothalamic dysfunction from tumor (e.g. adenoma) or hypo-perfusion (w/infarct)
- Direct pit/hypothal dysfunction from systemic diseases: infiltrative processes (e.g. sarcoid) or iron deposition (hemochromatosis)
- Meds affecting pit/hypothal axis→ chronic narcotics, LHRH agonists for prostate ca
- Other chronic diseases that impact pit/hypothal axis → HIV, Dm, copd, chf, renal failure, cirrhosis
- Decreased libido
- Fatigue and decreased strength
- Erectile dysfunction
- Findings vary w/degree of hypo testosterone: can have small testes, decreased muscle mass, decreased axillary/pubic/facial hair, breast development
- Sometimes findings related to an underlying systemic dz, e.g.: Hemochromatosis→dark skin, chronic liver dz; Sarcoid→wheezing; etc.