endocrine/ reproductive Flashcards
How do the testes develop and migrate in males?
The testes develop in the abdomen and migrate down through the inguinal canal into the scrotum, typically reaching the scrotum before birth
What is the condition called when testes have not descended by birth?
known as undescended testes or cryptorchidism, occurring in about 5% of boys.
Give 3 RFs for undescended testes
- Low birth weight
- Small for gestational age
- Prematurity
What is the management approach for unilateral undescended testes in newborns?
- Watchful waiting: Appropriate in newborns, as most testes descend in the first 3 months
- referral should be considered from around 3 months, ideally seeing a urological surgeon before 6 months of age
- Orchidopexy: Surgical correction between 6 and 12 months of age.
What is the management for bilateral undescended testes?
should be reviewed by a senior paediatrician within 24 hours, as the child may need urgent endocrine or genetic investigations.
What is the difference between a retractile testis and an undescended testis?
A retractile testis can be easily manipulated into the scrotum without tension, whereas an undescended testis cannot be moved down into the scrotum easily
Give 3 complications of undescended testis
- infertility
- torsion
- testicular cancer
What are the two types of hypothyroidism in children
can be congenital or acquired
Why is thyroid hormone essential, and what are the risks of undiagnosed hypothyroidism in children?
- Thyroid hormone is crucial for the development and functioning of the brain and body
- Undiagnosed hypothyroidism can result in significant neurodevelopmental problems and intellectual disability.
What is congenital hypothyroidism
when a child is born with an underactive thyroid gland
What causes congenital hypothyroidism
- Dysgenesis: An underdeveloped thyroid gland.
- Dyshormonogenesis: A fully developed gland that produces insufficient hormone
- Iodine deficiency (mc cause in developing world)
- rarely, issues with the pituitary or hypothalamus.
How is congenital hypothyroidism typically detected in infants?
Most infants with congenital hypothyroidism are detected through routine neonatal biochemical screening (Guthrie test), which identifies raised TSH levels in the blood
What are the clinical features of congenital hypothyroidism?
- Faltering growth
- Feeding problems
- Prolonged jaundice
- Constipation
- Pale, cold, mottled, dry skin
- Large tongue
- Delayed development
What is acquired hypothyroidism?
when a child or adolescent develops an underactive thyroid gland after previously normal function
What is the most common cause of acquired hypothyroidism?
autoimmune thyroiditis, aka Hashimoto’s thyroiditis, which causes autoimmune inflammation of the thyroid gland
What antibodies are associated with Hashimoto’s thyroiditis?
antithyroid peroxidase (anti-TPO) antibodies and antithyroglobulin antibodies
What are some autoimmune conditions associated with acquired hypothyroidism?
type 1 diabetes
vitiligo
coeliac disease
What are the symptoms of acquired hypothyroidism?
- Fatigue and low energy
- Weight gain
- short stature/ poor growth
- Poor school performance/ concentration
- Constipation
- cold intolerance
- Dry skin and hair loss
How is hypothyroidism managed
- Levothyroxine once daily
- Doses are titrated based on thyroid function tests and symptoms.
What is Kallmann’s syndrome?
a genetic condition that causes delayed puberty due to hypogonadotropic hypogonadism
How is Kallmann’s syndrome inherited?
typically inherited as an X-linked recessive trait
What causes Kallmann’s syndrome?
results from the failure of GnRH-secreting neurons to migrate to the hypothalamus
What are the features of Kallmann’s syndrome?
- Delayed puberty
- Hypogonadism and cryptorchidism
- Anosmia (loss of sense of smell)
- Low sex hormone levels
- Inappropriately low/normal LH and FSH levels
- Typically normal or above-average height
What is the management for Kallmann’s syndrome?
- Testosterone supplementation
- Gonadotrophin supplementation may help achieve sperm production if fertility is desired later in life.
How is congenital adrenal hyperplasia inherited
autosomal recessive pattern
What causes congenital adrenal hyperplasia
- 21-hydroxylase deficiency (90%)
- 11-beta hydroxylase deficiency (5%)
- 17-hydroxylase deficiency (very rare)
Explain the pathophysiology of congenital adrenal hyperplasia
- 21-hydroxylase is responsible for converting progesterone into aldosterone and cortisol
- Hydroxylase deficiency causes underproduction of cortisol and aldosterone and compensatory overproduction of androgens
Clinical features of congenital adrenal hyperplasia caused by 21-hydroxylase deficiency
- virilisation of female genitalia (ambiguous genitalia)
- 70% have a salt-wasting crisis at 1-3 weeks of age
- precocious puberty in males
features of a salt wasting crisis in congenital adrenal hyperplasia
- dehydration
- hypotension
- electrolyte imbalances: hyponatraemia, hyperkalaemia and hypoglycaemia
- can be life-threatening if not treated promptly
Clinical features of congenital adrenal hyperplasia caused by 11-beta hydroxylase deficiency
- virilisation of female genitalia
- precocious puberty in males
- hypertension
- hypokalaemia
Clinical features of congenital adrenal hyperplasia caused by 17-hydroxylase deficiency
- non-virilising in females
- inter-sex in boys
- hypertension
Common clinical presentations of congenital adrenal hyperplasia
- precocious puberty
- infertility
- height and growth abnormalities: Children with CAH often experience accelerated growth rates initially but may have a shorter adult stature due to early epiphyseal closure
- virilisation
- salt-wasting crisis
How is congenital adrenal hyperplasia managed
- primarily involves glucocorticoid replacement (hydrocortisone) to reduce ACTH levels and minimize adrenal androgen production
- fludrocortisone for mineralocorticoid deficiency (aldosterone)
What is precocious puberty
development of secondary sexual characteristics before 8 years in females and 9 years in males
