Disorders of gonads Flashcards
What is the typically presentation of male hypogonadism?
Usually symptoms of androgen deficiency:
Poor libido Erectile dysfunction Loss of secondary sexual hair Small soft testes Gynaecomastia
Name 3 congenital causes of primary gonadal disease in males
Anorchia (absence of both testes)
Leydig cell agenesis
Cryptorchidism (testicular maldescent)
Chromosome abnormalities e.g. Klinefelter syndrome
Enzyme defects: 5 alpha-reductase deficiency
(5a-reductase converts testosterone into the more potent dihydrotestosterone)
Name 3 acquired causes of primary gonadal disease in males
Testicular torsion Orchidectomy Local testicular disease Chemotherapy/radiation toxicity Orchitis e.g. mumps CKD Cirrhosis/alcohol Sickle cell disease
Explain how CKD causes hypogonadism
Renal failure is associated with decreased luteinizing hormone (LH) production, and decreased prolactin (PRL) clearance.
Hyperprolactinaemia inhibits GnRH release from the hypothalamus.
Uraemia inhibits LH receptors.
Name 2 causes of secondary gonadal failure in males
Hypopituitarism e.g. tumours, iatrogenic Normosmic idiopathic hypogonadotropic hypogonadism Kallmann syndrome Severe systemic illness Severe underweight
(Hyperprolactinaemia)
What investigations should be measured in
male hypogonadism?
Basal testosterone, LH, FSH
Semen analysis, chromosomal analysis, bone-age estimation
Pituitary MRI, prolactin, pituitary function test
Describe the management of male hypogonadism
Underlying cause is rarely reversible. Testosterone replacement therapy to control symptoms and prevent long-term osteoporosis.
Gonadotrophin deficiency: LH and FSH replacement, or pulsatile GnRH if fertility required.
How is cryptorchidism (undescended testes) managed?
Surgical exploration and early orchidopexy in early childhood.
HCG trial may induce descent.
After puberty: Orchidectomy advised
What is Klinefelter syndrome?
A common congenital abnormality (1:1000 males) featuring an extra X chromosome (47,XXY)
How does Klinefelter syndrome present?
Patients usually present in adolescence with poor sexual development, small or undescended testes, gynaecomastia, or infertility.
Long leg length, tall stature due to lack of epiphyseal fusion in puberty.
Signs of androgen deficiency including small, pea-sized but firm testes and gynaecomastia.
Occasional behavioural problems and learning difficulties.
What is the treatment for Klinefelter syndrome?
Androgen replacement therapy unless testosterone levels are normal.
No treatment possible for infertility and abnormal seminiferous tubules.
What is Kallmann syndrome?
Isolated GnRH deficiency characterised by delayed/absent puberty and impaired sense of smell.
Define erectile dysfunction and briefly describe its aetiology
Erectile dysfunction is the inability to achieve or maintain erection. May be associated with lack of libido, both are common symptoms of male hypogonadism.
ED may be psychological, neurogenic (most common with DM), vascular (PVD), endocrine, or related to drugs.
What is the treatment of erectile dysfunction?
Stop any offending drugs
Sildenafil* aka Viagra (Phosphodiesterase inhibitor)
Also consider injections and implants
Psychosexual counselling if psychological cause
Define gynaecomastia and state 3 causes
Development of breast tissue in males
Can be physiological Hyperthyroidism Hyperprolactinaemia Renal and liver disease Hypogonadism Oestrogen-producing tumours (testis, adrenal) HCG-producing tumours (testis, lung) Drugs: Spironolactone*, oestrogen, digoxin
