• Credits

  • Section Writer: Dr. Om J Lakhani
  • Section Editor: Dr. Om J Lakhani

• Q. Why is the timing of testosterone defect important in congenital abnormalities of primary hypogonadism?

  • Defect in 1st trimester- male external genitalia would not be adequately formed – ambiguous genitalia or female external genitalia
  • Normal Trimester in the first trimester but defective in 3rd trimester  - micropenis at birth
  • Normal Testosterone in utero, Testosterone defect before puberty- absent secondary sexual characteristic, Eunhacnoid proportions, gynecomastia
  • Testosterone defect after puberty – normal virilization, gynecomastia, testicular atrophy, reduced libido, infertility

• Q. What is the typical phallus length in prepubertal testosterone deficiency?

  • Stretched penile length <8 cm

• Q. What are the features of Prepubertal testosterone deficiency?

  • Eunuchoid proportions
  • Absent spermarche
  • Small testis
  • Small phallus - <8 cm
  • May have gynecomastia
  • Absent acne
  • Absent temporal hair recession
  • High pitched voice
  • Body composition - female
  • Female eschaton
  • Reduce muscle mass
  • Absent pigmentation and rugosity of scrotum

• Q. What are the features of eunuchoid proportions?

  • lower segment > Upper segment by 2 cm
  • Arm spam > height by 5 cm

• Q. Summarize the clinical features of male hypogonadism based on the age of onset and whether it is primary or secondary hypogonadism?

Prepubertal onset of hypogonadism

Post-pubertal onset

Pre-pubertal versus post pubertal onset hypogonadism

• Q. Give the algorithm for an approach to male hypogonadism?

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• Q. What are the indications for doing MRI in male hypogonadism?

  • Increase prolactin
  • Male <40 with testosterone <250 ng/dl
  • Male >60 years with testostetrone <150 ng/dl

• Q. In which conditions is SHBG tested?

  • Obesity – SHBG reduced
  • Aging- SHBG increased

• Q. In which cases is SHBG increased?

  • Aging
  • Estrogen
  • Hyperthyroidism
  • Anti-epileptics
  • HIV

• Q. in which cases is SHBG reduced?

  • Obesity
  • Insulin resistance
  • Androgens
  • Hypothyroidism
  • Glucocorticoids
  • Nephrotic syndrome
  • Acromegaly

• Q. What is a male escutcheon, and what is a female escutcheon?

  • Pattern of pubic hair
    • Male escutcheon – diamond shape
    • Female escutcheon – inverted triangle shape