Paeds Endo + Repro Flashcards
What is Cushings syndrome
excessive cortisol levels
what are two groups of corticosteroids
Glucocorticoids (e.g., cortisol)
Mineralocorticoids (e.g., aldosterone)
where is cortisol produced
adrenal glands.
what is cushings disease
pituitary adenoma secreting excessive adrenocorticotropic hormone (ACTH), stimulating excessive cortisol release from the adrenal glands.
what medication can cause cushings syndrome
exogenous corticosteroids, such as prednisolone or dexamethason
what are features of cushings
Round face (known as a “moon face”)
Central obesity
Abdominal striae (stretch marks)
Enlarged fat pad on the upper back (known as a “buffalo hump”)
Proximal limb muscle wasting (with difficulty standing from a sitting position without using their arms)
Male pattern facial hair in women (hirsutism)
Easy bruising and poor skin healing
Hyperpigmentation of the skin in patients with Cushing’s disease (due to high ACTH levels)
what are metabolic effects of cushings
Hypertension
Cardiac hypertrophy
Type 2 diabetes
Dyslipidaemia (raised cholesterol and triglycerides)
Osteoporosis
what are mental health effects of cushings
Anxiety
Depression
Insomnia
Rarely psychosis
what are causes of Cushing’s syndrome
C – Cushing’s disease (a pituitary adenoma releasing excessive ACTH)
A – Adrenal adenoma (an adrenal tumour secreting excess cortisol)
P – Paraneoplastic syndrome
E – Exogenous steroids (patients taking long-term corticosteroids)
what is Mc cause of Paraneoplastic Cushing’s syndrome
Small cell lung cancer
ectopic ACTH
how is Cushing’s syndrome diagnosed
Dexamethasone Suppression Tests
what is a normal response to Dexamethasone
suppressed cortisol due to negative feedback.
negative feedback on the hypothalamus, reducing the corticotropin-releasing hormone (CRH) output. It causes negative feedback on the pituitary, reducing the ACTH output. The lower CRH and ACTH levels result in a low cortisol
what does a lack of cortisol suppression to dexamethasone suggests
Cushing’s syndrome.
what are three types of dexamethasone suppression test:
Low-dose overnight test
Low-dose 48-hour
High-dose 48-hour test
what is Low-dose overnight test used for
a screening test to exclude Cushing’s syndrome
what is a Low-dose 48-hour test used for
used in suspected Cushing’s syndrome
what is a high-dose 48-hour test used for
used to determine the cause in patients with confirmed Cushing’s syndrome
how is low-dose overnight test given
dexamethasone (1mg) is given at night (usually 10 or 11 pm), and the cortisol is checked at 9 am the following morning.
Failure of the dexamethasone to suppress the morning cortisol could indicate Cushing’s syndrome, and further assessment is required.
how is a Low-dose 48-hour test given
dexamethasone (0.5mg) is taken every 6 hours for 8 doses, starting at 9 am on the first day. Cortisol is checked at 9 am on day 1 (before the first dose) and 9 am on day 3 (after the last dose).
Failure of the dexamethasone to suppress the day 3 cortisol could indicate Cushing’s syndrome, and further assessment is required.
how is a high-dose 48-hour test given
dexamethasone (2mg) is taken every 6 hours for 8 doses, starting at 9 am on the first day. Cortisol is checked at 9 am on day 1 (before the first dose) and 9 am on day 3 (after the last dose)
what is the higher dexamethasone dose able to suppress cortisol in
in Cushing’s syndrome caused by a pituitary adenoma (Cushing’s disease)
but not when it is caused by an adrenal adenoma or ectopic ACTH.
what test result differentiates Adrenal Adenoma and Ectopic ACTH
ACTH
Low in adrenal adenoma
High in ectopic ACTH
what other investigations can be carried out for cushings
24-hour urinary free cortisol
Full blood count may show a high white blood cell count
U&Es may show low potassium if an adrenal adenoma is also secreting aldosterone
MRI brain for a pituitary adenoma
CT chest for small cell lung cancer
CT abdomen for adrenal tumours
what sign is indicative of Cushing’s disease or ectopic ACTH cause of Cushings syndrome
skin pigmentation
sign is absent in an adrenal adenoma or exogenous steroids.
how is cushings treated
Trans-sphenoidal (through the nose) removal of pituitary adenoma
Surgical removal of adrenal tumour
Surgical removal of the tumour producing ectopic ACTH (e.g., small cell lung cancer), if possible
what is a complication of surgical removal of both adrenal glands and what is it
Nelson’s syndrome.
development of an ACTH-producing pituitary tumour due to lack of cortisol and negative feedback
what medication is sued to reduce the production of cortisol in the adrenals
Metyrapone
what are two types of Hypothyroidism in children
congenital or acquired
what can untreated hypothyroidism in children lead to
significant problems with neurodevelopment and intellectual disability.
what is Congenital hypothyroidism
child is born with an underactive thyroid gland.
what is dyshormonogenesis
fully developed gland that does not produce enough hormone
what is dysgenesis
underdeveloped thyroid gland
when is Congenital hypothyroidism screened
newborn blood spot screening test.
how does Congenital hypothyroidism present
Prolonged neonatal jaundice
Poor feeding
Constipation
Increased sleeping
Reduced activity
Slow growth and development
what is Acquired hypothyroidism
a child or adolescent develops an underactive thyroid gland when previously it was functioning normally.
what is MC cause of acquired hypothyroidism
autoimmune thyroiditis, also known as Hashimoto’s thyroiditi
what is Hashimoto’s associated with
antithyroid peroxidase (anti-TPO) antibodies and antithyroglobulin antibodies
