The Male Genito-urinary System

Question 1

Androgens

Answer 1

Produced in the adrenal cortex from zona reticularis

• Testosterone
• Dihydrotestosterone
  
  • formed from testosterone
  • produced by 5-a-reductase

Question 2

Maturation of sperm

Answer 2

*Hypothalamus

(GnRH)

*Pituary*

(LH) (FSH)

^{^^}Leydig Seroteli^{^}

Testosterone Spermatogenesis

Mature sperm

Question 3

Where does the prodcution of sperm take place?

And what is the process of sperm maturation?

Answer 3

Sperm is produced in th eseminiferous tubules in the testes.

Spermatogonium (x1)

Prmry spermocyte (x1)

2ndry spermocyte (x2)

Spermatids (x4)

Spermatozoa (x4)

Question 4

Impaired Spermatogenesis: Infertility

Answer 4

Male infertility is when < 20mil sperm/mL semen

(Normal: 50-150/mL)

Causes:

• ↑testicular temp
• undescended testes
• testicular infection (e.g adult onset mumps)
• ↓LH→↓testosterone for spermatogenesis
• genetic disorders
• abnormal #chromosoms→↓testosterone

Question 5

Impaired spermatogenesis

Define non-motile sperm & non-viable sperm

Answer 5

Non-motile sperm:

• not able to propel within female reprod tract

Non-viable sperm:

• immature/malformed sperm
• unable to fertilize ovum

Question 6

Erection

Answer 6

Vasodilatino fills spongy tissue with blood

(corpus cavernosum surrounds the cental arteries)

Question 7

What is Erectile Dysfunction?

Answer 7

Erectile dysfunction is the impairment of ejaculation and/or erection

Question 8

What are some causes of erectile dysfunction?

Answer 8

• Physiological and/or emotional/physchological problems
• >40yo men: 50% physiological
  
  • vascular/endocrine/neuro disorders
  • chronic disease
  • penile diseases and trauma
  • iartrogenic (externally admin) eg drugs, surgery
• younger men:
  
  • psychological causes

Question 9

What are some drugs that cause penile dysfunction?

Answer 9

• Antihypersensitives
• Antidepressants
• Antihistamines
• Tranquillisers
• Barbituarates
• Diuretics
• Narcotics
• Alcohol
• Marijuana

These inhibit desire & erections

Can cause sperm abonormalities

Question 10

What are some penile disorders?

Answer 10

Inflammations

• Balanitis
• Balanoposthitis
• Peyronie’s disease (fibrous plaque forms on the corpus cavernosum - spongy tissue- causes penis to bend upwards when erect)

Penile cancer

Priapism

Question 11

What are some testicular disorders?

Answer 11

Variocele

Hydrocele

Haematocele

Spermatocele

Question 12

What is testiculat torison?

Answer 12

When the spermatic chord is twisted (arteries & veins)

• torison twists
• reduce/stoped circulation to testis
• scrotal swelling & pain
• most common in neonates & young adolescents

Question 13

What is epididiymitis?

Answer 13

Testicular disorder: Inflammation of the epididymis

• STI - urethritis
• Non-STI - UTI or prostatitis

Question 14

What is orchitis?

Answer 14

Testicular disoorder: Accute inflammation of testes

• usually from mumps

Question 15

What is cryptorchidism?

Answer 15

Testicular disorder: Undescended testes

Question 16

What is cancer of the testis?

Answer 16

Testicular disorder: Painless enlargment of the testis (usually RHS)

• most curable type of cancer
• 1% of cancers
• most common cancer in men 15-35

Question 17

What is cancer?

Answer 17

Germline and somatic mutations

Inherited cancer:

• Germ-line
• Somatic mutations

Sporadic cancer:

• Double-somatic
• Single somatic

Question 18

Describe the process of cancer formation

Answer 18

Multi-step process

Tumorogenic progression:

• normal⁺
• hyperplasia⁺
• dysplasia⁺
• invasive^*
• metastatic^*

*Malignant

^<em>+</em>Benign

Question 19

The prostate surrounds the urethra

(at base of penis, not at tip)

What happens in prostate cancer?

Answer 19

• Prostate enlargment → compressed urethra
• Causes alterations in urination
  
  • weak stream
  • urgency
  • dysuria
  • discharge

Question 20

What different types of prostatis are there?

Answer 20

• Asymptomatic inflammatory
• Acute bacterial
• Chronic bacterial
• Chronic prostatis/pelvic pain syndrome
  
  • inflammatory
  • noninflammatory

Question 21

What is BPH and how would you diagnose it?

(Benign Prostatic Hyperplasia)

Answer 21

• Nodules compress urethra to a narrow slit
• Urine from bladder cannot enter urethra

Diagnosis:

• Physical examination
  
  • ultrasound probe
  • finger

Question 22

What is prostate cancer?

Answer 22

• Common cancer amongst men
• generally older men
• associated w/Western culture

Diagnosis:

• history
• digital rectal examination
• transrectalultrasound
• prostate specific antigen (PSA)

Treatment:

• Surgical removal of prostate
• chemotherapy
• radiotherapy
• hormonal therapy
• testosterone inhibitors
  
  • extremley important for metastatic disease

Question 23

Which type of prostatitis is most common?

(a) Assymptomatic inflammatory

(b) Acute bacterial

(c) Chronic bacterial

(d) Pelvic pain syndrome

Answer 23

(Chronic) **Pelvic Pain Syndrome **(CPPS)

Question 24

True or False:

Male reproductive hormones are regulated by the HPA axis? (Hypothalamic-Pituary-Adrenal axis)

Answer 24

False.

The regulation of reproductive hormones is accomplished by the HPG axis (hypothalamic-pituitary-gonadal). Gonads are sex organs.

Question 25

Which testicular disorder would be the most likely to result from trauma to the scrotum?

(a) Varicocele

(b) Hematocele

(c) Spermatocele

(d) Testicular torsion

Answer 25

(b) Hematocele

Hematocele is characterized by the accumulation of blood in the tunica vaginalis, and may be caused by scrotal trauma.

Varicoceles are varicosities in veins supporting the testes.

Spermatoceles are cysts at the end of the epididymis.

Testicular torsion is caused by the twisting of the spermatic cord.