Paediatric Endo Flashcards
What is cryptorchidism?
Udescended testes
What percentage of undescended testes are bilateral?
30%
RF for undescended testes?
Family history, low birth weight, preterm delivery, disorders of sexual development, maternal smoking, previous inguinal hernia surgery
What are true undescended testes?
Testes that lie along the normal path of development- in the abdomen or in the inguinal canal
What are ascending testes?
Testes that were previously in the scrotum but have moved into a higher position - may be due to a persisting processes vaginalis
When are infants screened for undescended testes
Within 72 hours of birth and then at 6-8 weeks
List some complications of undescended testes
Infertility
Testicular cancer
Torsion
At what ages should infants be referred to urology for undescended testes?
Around 3 months (surgery should happen before 6 months
Differentials of undescended testes?
Retractile testes
Absent testes (intersex conditions)
What surgery is performed for undescended testes?
Orchidopexy
What is testicular torsion?
Twisting of the spermatic cord leading to testicular ischaemia and necrosis
What deformity increases the likelihood of testicular torsion
The bell clapper deformity
How does testicular torsion present?
Severe sudden onset pain
Nausea and vomiting
Testicular swelling and erythema
Testes are retracted upwards
Loss of cremasteric reflex
Absent Prehn’s sign
What is prehn’s sign
Where elevation of the testes relieves pain - present in epididymitis by not torsion
Differentials of testicular torsion
Trauma, epididymitis, testicular torsion, hydrocele
What are the two types of testicular torsion
Extravaginal and intravaginal
How is testicular torsion investigated
Surgical exploration- no imaging
Treatment of testicular torsion
Detorsion and fixation (fix both testes as bell clapper is often bilateral)
Define precocious puberty
The development of secondary sexual characteristics before 8 years in females and before 9 years in males.
What is thelarche
The first stage of breast development
What is adrenarche
The first stage of pubic hair development
Who is precocious puberty more common in ?
Girls
More common in Afro-carribbean
How can precocious puberty be classified
Gonadotrophin dependent (true) and gonadotrophin independent (pseudo)
Explain gonadotrophin dependent precocious puberty
Occurs due to premature activation of the hypothalamic-pituitary axis- leads to raised FSH and LH
List some causes of gonadotrophin dependent precocious puberty
Idiopathic
Brain neoplasms
Post traumatic brain injury
Cranial radiotherapy
Explain gonadotrophin independent precocious puberty
Occurs due to an excess of sex hormones (oestrogen and testosterone). The FSH and LH will be low.
List some causes of gonadotrophin independent precocious puberty
Ovarian causes- follicular cysts, granulosa cell tumours, leydig cell tumours
Testicular causes- leydig cell tumours
Adrenal causes (21-hydroxylase deficiency in congenital adrenal hyperplasia)
McCune- Albright syndrome
Exposure to exogenous hormones (e.g contraceptive pill, testosterone gel)
If precocious puberty presents with bilateral testicular enlargement, what is the likely cause
Gonadotrophin release from an intracranial lesion (true precocious puberty)
Presentation of precocious puberty
- tall stature in childhood (will become small due to early fusion of the epiphyseal growth plate)
- breast development
- testes >4cm
- pubic/axillary hair
- menarche
- cafe au lait spots in McCune-Albright
How is precocious puberty diagnosed
- FSH and LH levels
- GnRH stimulation test
- Oestrogen and testosterone levels
- pelvic USS - check for ovarian cysts
How is precocious puberty treated?
Treat underlying cause
If gonadotrophin dependent consider GnRH analogue (goserelin)
Consider growth hormone as treating with GnRH agonist can suppress height)
What is Kallman syndrome
A type of hypogonadotrophic hypogonadism disorder which results in a decrease in sex hormones and underdevelopment of primary and secondary sexual characteristics
Pathophysiology of kallman’s syndrome
There is failure of migration of the neurones from the olfactory placode, This includes:
- GnRH secreting neurones (leading to decreased GnRH, FSH and LH)
- olfactory neurones (leading to anosmia)
How does Kallman’s syndrome present
Delayed puberty - small penis and testes, lack of breast development, lack of pubic hair, lack of facial hair etc
Cryptorchidism
Anosmia
Patients commonly tall
Skeletal abnormalities - scoliosis, short middle finger
May also have hearing and visual disturbances
Aetiology of Kallman syndreom
Genetic condition- commonly due to an X-linked recessive trait
Is Kallman syndrome more common in boys or girls
Much more common in boys
How is Kallman syndrome diagnosed?
- hormone levels: sex hormones low, LH/FSH low, GnRH low
- Genetic testing
How is Kallman syndrome treated?
Hormone therapy- testosterone supplementation to stimulate sexual characteristics
gonadotrophin supplementation may help with sperm production
Calcium and vitamin D (at risk of osteoporosis)
What is a potential long term complication of Kallman syndrome and why?
Osteoporosis as testosterone and oestrogen are protective against bone absorption
what is congenital adrenal hyperplasia ?
A group of autosomal recessive disorders that impair steroid biosynthesis
Pathophysiology of congenital adrenal hyperplasia
- There is a deficiency in an enzyme which is needed to produce cortisol (most commonly 21-hydroxylase)
- This leads to a deficiency in cortisol
- This causes the anterior pituitary to produce a compensatory overproduction of adrenocorticotropic hormone (ACTH)
- The increased ACTH leads to an increase in production of adrenal androgens that can lead to virilization of female infants and affect genital development
Presentation of congenital adrenal hyperplasia
Virilization of female external genitalia-female infants will present with ambiguous genitalia due to excessive androgen exposure in utero.
Male infants often appear normal at birth
Salt wasting crisis
Precocious puberty
Infertility
Height and growth abnormalities (accelerated in childhood but short adult height)
What is salt-wasting crisis and why does it occur in congenital adrenal hyperplasia
Occurs in around 70% of those with 21-hydroxylase deficiency
These patients are also unable to make aldosterone (As well as cortisol) meaning there is salt loss
How does salt wasting crisis present?
Dehydration, hypotension and electrolyte imbalances
What hormone deficiencies can cause congenital adrenal hyperplasia?
21- hydroxylase (90%)
11- beta hydroxylase
17- hydroxylase
What does 21-hydroxylase deficiency lead to
Impaired conversion of 17-hydroxyprogesterone to 11-deoxycortisol
How is congenital adrenal hyperplasia diagnosed
Many countries screen for CAH in newborns (not in the UK) - test 17-hydroxyprogestone levels
ACTH stimulation testing - 17-hydroxyprogesterone is measured, ACTH is administered and the level of 17-OHP is measured again. An abnormal rise in 17-OHP indicates congenital adrenal hyperplasia
How is congenital adrenal hyperplasia treated
Glucocorticoid replacement - hydrocortisone
If aldosterone deficiency- mineralocorticoid replacement (fludrocortisone)
May need surgery -feminising genitoplasty
What is androgen insensitivity syndrome
An x linked recessive condition where there is a mutation in the androgen receptor gene causing a defective androgen receptor on the external genitalia (means there cannot be a response to testosterone)
Describe the phenotype of a patient with androgen insensitivity syndrome
A genetic male with a female phenotype -will have female external genitalia
Why don’t patients with androgen insenstivity syndrome develop internal female genitalia
the testes produce anti-mullerian hormone which prevents development of internal female genitalia
What is the inheritance of androgen insensitivity syndrome
x linked recessive
treatment of androgen insensitivity syndrome
oestrogen therapy
bilateral orchidectomy
vaginal dilators/ surgery
what two types of hypothyroidism can children experience
congenital - from birth
acquired
pathophysiology of congenital hypothyroidism
can be due to an underdeveloped thyroid gland (dysgenesis) or a fully developed gland that doesnt produce enough hormono (dyshormonogenesis)
most common cause of acquired hypothyroidism in children
autoimmine thyroid (hashimotos) - anti-TPO and anti thyroglobulin
How does congential hypothyroidism present?
prolonged neonatal jaundice
poor feeding
contsipation
increased sleeping
reduced activity
slow growth and development
When older- delayed mental and physical milestones, short stature, puffy face, hypotonia
What defines delayed puberty
the absence of any pubertal development by 13 in girls and 14 in boys
- in girls this is the absence of any breast budding
- in boys this is a testicular volume less than 4ml
what is the order of pubertal development in girls
breast budding
pubic hair
menstrual periods
what is the order of pubertal development in boys
enlargement of the testes
enlargement of the penis
gradual darkening of the scrotum
development of pubic hair
deepening of the voice
What are the three broad types of pubertal delay
functional delay
hypergonadotrophic hypogonadism
hypogondadotrophic hypogonadsim
What can cause functional delay in puberty
constitutional delay
excessive exercise or stress
chronic illness
malnutrtion
explain what hypogonadotrophic hypogonadism is
a cause of delayed puberty where there is a decrease in gonadotrophin (LH and FSH) - leads to a decrease in oestrogen and testosterone
give some examples of hypogonadotrophic hypogonadism
damage to the pituitary gland or hypothalamus (radiotherapy, surgery)
growth hormone deficiency
hypothyroidism
hyperprolactinaemia
Kallman syndrome
explain what hypergonadotrophic hypogonadism is
a condition where the gonads to not respond to LH and FSH leading to reduced oestrogen and testosterone, and a subsequent increase in LH and FSH due to lack of negative feedback
causes of hypergonadotrophic hypogonadism
previous damage to the gonads (mumps, cancer, torsion)
congenital absence of testes or ovaries
Kleinfelter’s syndrome
Turners syndrome
causes of delayed puberty with short stature
Turner’s, Prader-Willi, Noonan’s
causes of delayed puberty with normal stature
PCOS, androgen insensitivity, Kallman’s, Klinefelter’s
what investigations may be done for delayed puberty
tanner staging
wrist x-ray to obtain bone age
LH and FSH levels
growth hormone
prolactin
genetic testing
oestrogen and testosterone level
What may be involved in the treatment of delayed puberty?
hormone replacement therapy- oestrogen or testosterone
How does congenital hypothyroidism present?
prolonged neonatal jaundice
poor feeding
constipation
increased sleeping
reduced activity
slow growth and development
when older- delayed mental and physical milestones, short statue, puffy face, hypotonia
pathophysiology of congenital hypothyroidism
either underdeveloped gland (dysgenesis) or fully developed gland that doesnt produce enough hormone (dyshormonogenesis)
