Paeds - Endocrine, Oncology, Neonatal Flashcards
what is congenital hypothyroidism?
child is born with an underactive thyroid gland. This occurs in around 1 in 3000 newborns.
what two ways does congenital hypothyroidsm occur
dysgenesis - thyroid gland is underdeveloped
dyshormonogenesis - fully developed gland that does not produce enough hormone
how is congenital hypothyroidism picked up
newborn blood spot screening test
what is the presentation of congenital hypothyroidsm (6)
-poor feeding
-constipation
-increased sleeping
-reduced activity
-slow growth and development
-prolonged neonatal jaundice
what is hashimotos thyroiditis
an acquired autoimmune hypothyroidism leading to inflammation of the thyroid gland
what antibodies is hashimotos thyroiditis associated with (2)
-antithyroid peroxidase (anti-TPO)
-antithyroglobulin antibodies
Sx of hashimotos thyroditis
-Fatigue and low energy
-Poor growth
-Weight gain
-Poor school performance
-Constipation
-Dry skin and hair loss
Ix of hypothyroidism (3)
thyroid function blood tests (TSH, T3 and T4), thyroid ultrasound
thyroid antibodies
Mx of hypothyroidism
Levothyroxine once daily
risk factors for undescended testes (5)
Family history of undescended testes
Low birth weight
Small for gestational age
Prematurity
Maternal smoking during pregnancy
What is cryptorchidism
A congenital condition where the testis fail to reach the bottom of the scrotum by 3 months of age
Complications of cryptorchidism
-risk of infertility
-increased risk of testicular seminoma (cancer)
-testicular torsion
Tx of cryptorchidism (3)
Orchidopexy at 6- 18 months of age - mobilisation of testis into dartos pouch ( bottom of scrotum)
Intra-abdominal testis - evaluated laparoscopically and mobilised.
Past 2 years
Orchidectomy as decreased risk of malignancy
What is retractile testicles
Before puberty the testes move out the scrotum into the inguinal canal due to cremasteric reflex
Sometimes do not come back down and need orchidopexy
what is hypogonadotropic Hypogonadism
deficiency in LH and FSH (gonadotrophins)
leading to a deficiency in oestrogen and testosterone
what is the root cause of hypogonadotrophic hypogonadism
abnormal functioning of pituitary gland
give 5 causes of hypogonadotropic Hypogonadism
-damage to hypothalamus or pituitary
-tumours - astrocytomas, craniopharygiomas, prolactinomas
-GH deficiency
-Hypothyroidism
-Hyperprolactinameia (high prolactin)
-CF - delay puberty
-IBD - delay puberty
-kallmans syndrome
-excessive exercise or dieting -delays menstruation in girls
-bulimia
what is kallmans syndrome
-genetic condition resultig in the failure to start puberty and an impairment in smell
what is kallmans syndrome associated with
anosmia - absent smell
investigations for delay in puberty
categories
1. initial (3)
2. hormonal blood tests (4)
3.genetic tests (2)
4 imaging (3)
initial
-FBC + ferritin for anaemia
-U+E - for CKD
-Anti TTG/ anti EMA - coeliac
hormonal blood tests
-early morning LH + FSH - low in hypogonadotropic Hypogonadism
-TFTs
-GH tests - insulin like growth factor
-serum prolactin
Genetic testing
-kleinfelters
-turners
(can both cause delayed puberty
Imaging
-xray of the wrist to assess bone age
-pelvic ultrasound - assess ovaries
-MRI of the brain - pituitary pathology + assess olfactory bulbs (kallmans syndrome)
what is HYPERgonadotropic hypogonadism
- gonads dont respond to stimulation from the gonadotrophins (LH and FSH)
- There is no negative feedback from the sex hormones (testosterone and oestrogen),
-so anterior pituitary produces increasing amounts of LH and FSH to try harder to stimulate the gonads
what are the potential causes of hypergonadtropic hypogoandism
is due to abnormal functioning gonads
genetic:
-kleinfelters
-turners syndrome
-congenital abscence of the ovaries or testes
-previous damage to the gonads e.g testicular torsion
Management for a delay in puberty
-treat the underlying condition e.g GH deficiency
-replacement of sex hormones to induce puberty
what inheritance pattern is kallmanns syndrome
x linked recessive
features of kallmanns sydnrome
-delayed puberty
-hypogonadism
-cryptorchidism
-anosmia
-sex hormone levels low
-low FSH and LH
-patients above average height
-cleft lip
-visual/ hearing defects
Mx of kallmanns syndrome
-testosterone supplementation
-Gonadatrophin (LH/FSH) supplementation
typical epidemiology of kallmanns syndrome
lack of smell in a boy with delayed puberty
what is androgen insensitivity syndrome
condition where cells are unable to respond to androgen hormones due to a lack of androgen receptors
what inheritance pattern is androgen insensitivity syndrome
X linked recessive
Sx of androgen insensitivity syndrome
-lack of pubic hair + facial hair
-taller in height - female
-infertility
-primary amenorrhoea - abscence of menstruation
-undescended testes
-breast developement
Why do males with androgen insensitivity syndrome develop external female characteristics
-the males produce testosterone but there is no response to it
-there is also conversion of additional androgens to oestrogen
-this leads to a female phenotype externally
Presentation of someone with androgen insensitivity syndrome
-inguinal hernias containing testes in infancy
-primary amennorrhoea at puberty
Mx of androgen insensitivity syndrome
Bilateral orchidectomy - to avoid testicular cancer
Oestrogen therapy
Vaginal dilators and vagina surgery to create adequate vaginal length
Counselling - understand how to live with condition socially and sexually - normally raised as female
How to diagnose androgen insensitivity syndrome (2)
-buccal smear/ chromosome analysis to reveal 46 XY chromosome
-post puberty testosterone levels will be higher than normal
What is congenital adrenal hyperplasia
Congenital deficiency of 21 hydroxylase enzyme causing underproduction: Cortisol + Aldosterone
Overproduction of androgens
Inheritance pattern of Congenital adrenal hyperplasia
Autosomal recessive
Give three examples of steroid hormones
Androgens - e.g Testosterone
Glucocorticoids- e.g Cortisol
Mineralcorticoids - e.g Aldosterone
Pathophysiology of congenital adrenal hyperplasia
-21 hydroxylase normally converts progesterone into aldosterone and cortisol
-progesterone is also used to create testosterone
-the defect in the 21 hydroxylase means extra progesterone circulates with less conversion to
Aldosterone and cortisol
-gets converted to testosterone
Levels in Congenital adrenal hyperplasia in
Aldosterone
Cortisol
testosterone
Aldosterone - low
Cortisol - low
testosterone -high
How to diagnosis Congenital adrenal hyperplasia
-ACTH simulation testing measures adrenal gland response to ACTH
-newborn screen - not offered in UK
Presentation in MILD cases of congenital adrenal hyperplasia
Female patients - virilization (more manly)
Tall for age
Deep voice
Early puberty
Hyperpigmentation
Facial hair
Absent periods
Male patients
Tall for age
Deep voice
Early puberty
Hyperpigmentation
Large penis
Small testicles
Presentation of severe cases of Congenital adrenal hyperplasia
-ambiguous genitalia in females
-enlarged clitroris (due to high testosterone)
-skin pigmentation -due to ACTH
-salt wasting crisis which can lead to: - too little aldosterone
Poor feeding
Arrhythmias
Dehydration
Vomiting
In CAH what is salt wasting crisis and what three conditions does this cause
LIFE THREATENING
-adrenal glands make too little aldosterone, causing the body to be unable to retain enough sodium
-leads to hyponatraemia, hypoglycaemia + hypokalemia
Why skin hyperpigmention in CAH
-anterior pituitary gland responds to the low levels of cortisol by producing increasing amounts of ACTH
-A byproduct of the production of ACTH is melanocyte simulating hormone.
-This hormone stimulates the production of melanin (pigment) within skin cells.
Mx of CAH (3)
See paediatric endocrinologist
-Cortisol replacement - hydrocortisone,
-Aldosterone replacement - fludrocortisone
-Female patients with ambiguous genitals may require corrective surgery
What are gliomas
Tumours of the brain and spinal cord
What are the three types of glial cells
astrocytes
oligodendrocytes
ependymal cells
Types of gliomas - which one is most malignant
Astrocytoma (the most common and aggressive form is glioblastoma)
Oligodendroglioma
Ependymoma
Tx of gliomas
Radiation and chemotherapy
-correct hormone imbalances if necessary
What condition may increase risk of hypothalamic tumours
Neurofibromatosis
Sx of hypothalamic tumours
-euphoric sensations
-failure to thrive
-headache - fluid can collect in brain
-hyperactive
-loss of appetite
-vision loss
-seizures
What is precocious puberty
onset of secondary sexual characteristics in children at an age that is two standard deviations younger than the mean age of pubertal onset
What are the two types of precocious puberty
central + Peripheral
What is central precocious puberty
-early maturation of hypothalamic+pituitary gonadal axis
-early release of LH+FSH
-increases sex hormones
Causes of central precocious puberty
-largely idiopathic
-infection/cyst
-radiation damage to brain (reduced -ve feedback)
-GnrH secreting tumour
What is peripheral precocious puberty
Overproduction of sex hormones by gonads (GnRH independent)
Causes of peripheral precocious puberty (5)
-cyst/tumour
-genetic condtions - mccune Albright syndrome
-thyroid/ adrenal dysfunction
-exogenous hormones e.g creams
How to diagnose precocious puberty
-Tanner scale
-GnRH levels - see if dependent (central) or independent (peripheral)
-ultrasound/MRI - to look for abnormalities
Tx of precocious puberty
GnRH analogues - reduce LH/FSH production
Surgery to remove cyst/ tumour
What is testicular torsion
Twisting of the spermatic cord with rotation of the testicle which can lead to ischemia and necrosis
Presentation of testicular torsion
-Sudden onset severe scrotal pain,
-Abdominal pain - in boys always rule out TT
-nausea + vomiting.
-Tender testis.
-Overlying scrotal skin may be reddened and oedematous.