Endocrine Diseases Flashcards
Diabetic foot disease is a complication of diabetes caused by damage to what
Nerves and blood vessels
Diabetic man has: active ulceration, spreading infection, critical ischaemia, gangrene or unexplained hot, red swollen foot with or without the presence of pain. Previously had signs of peripheral vascular disease. What is this?
Diabetic foot disease
Why might a diabetic man have a fracture or dislocation in the foot with no preceding history of significant trauma?
He has active foot disease
Pathology/ cause of type 1 diabetes?
Autoimmune destruction of pancreatic beta cells, so no insulin made
Why do type 1 diabetics need injections Vs oral route of insulin?
Peptide hormones like insulin, cannot be taken orally
What happens when type 1 diabetics don’t get their insulin?
Excessively wasted
Develop ketoacidosis
Coma
Death
Liver involvement in diabetes?
It thinks you’re starving, so it goes into gluconeogenesis mode
When is ketoacidosis?
When plasma pH falls below 7.1
(That becomes life threatening, death within hours).
Normal is usually 7.4
Why might tissues become insensitive to insulin in type II diabetes?
Abnormal response of insulin receptors, or reduction in their number
Why is type 2 diabetes associated with obesity?
Chronic exposure to high levels of nutrients
What is the diagnostic criterion for diabetes?
Hyperglycaemia
What test diagnoses diabetes?
Glucose tolerance test
What results of glucose tolerance test indicates diabetes?
Patient ingests glucose load after fasting BG is measured. BG will normally return to fasting levels within an hour, but if elevation after two hours, = diabetes.
What unit to measure plasma glucose concentration? (In the UK).
Millimolar
Long term complications or hyperglycaemia?
Retinopathy
Neuropathy
Cardiovascular disease
Also nephropathy
Why potential blindness in diabetes?
Retinopathy- destruction of retina
Why are foot ulcers a problem with diabetics?
Shoes rubbing, they don’t feel it, develop ulcers, ulcers become infected, and the bacteria LOVES the high blood glucose. So wounds difficult to treat therefore amputations
Why would type 2 ever take exogenous insulin? Bc they’re still producing insulin, after all, sometimes even more!
Beta cells in the pancreas sometimes burn out cuz they’ve been churning out insulin for so long, bc of high BG
What are the stages of hypoglycaemia?
Inhibition of insulin secretion
Glucagon, epinephrine and GH secreted
Cortisol secreted
Cognitive days function
Lethargy
Coma
Convulsions
Permanent brain damage and death
Coma at what BG level, and death when?
Coma at like 1.7mM
Death at like 0.6mM
Other hormone secreted like 3.7
Growth during the foetal period is largely controlled by what
Nutritional intake, thyroid hormones, and insulin.
When does growth hormone become significant?
Around 10 months of age
Why is there a spike of growth hormone during puberty?
Androgens and oestrogens
How do androgens and oestrogens terminate growth during puberty?
Causing epiphyses of the long bones to fuse
During puberty, before androgens and oestrogens terminate growth by causing epiphyses of long bones, which hormones promote bone elongation and increased height, weight and body mass?
Growth hormone
IGF-I
Which hormone is a great influence on growth at the start, but steadily less so with increasing age?
Thyroid hormones
Pathology of congenital hypothyroidism?
Babies born normal size but unable to produce own th
Signs of congenital hypothyroidism
If left untreated, retarded growth, retain infantile facial features
What affect does TH have on growth hormone?
Permissive
Loss of permissive effect severely impacts on GH action.
Signs/ appearance of hypothyroid children Vs children deficient in GH?
HT children retain infantile proportions, whereas children deficient in GH are proportionally normal, just small (like a leprechaun)
How long before someone might starts to notice the affects of acromegaly?
Like 5-10 years, maybe need to cut off ring etc
Why might the rest of pituitary function be compromised in acromegaly?
Compression of pituitary gland due to growth of cells.
Eg thyroid hormone function lost
Pathology of Cushing’s syndrome
Excess corticosteroids
Biggest cause of Cushing’s syndrome (not equal to disease)
Taking excess steroids eg for asthma or IBD
What is the pathology behind Cushing’s DISEASE?
Pituitary tumour
Difference in pathology of gigantism vs acromegaly?
Hyper-secretion of GH in both. But in gigantism, due to a pituitary tumour BEFORE Epiphyseal plates of long bones close. = excessive growth.
Vs after
Classic sign of acromegaly to do with feet?
Adult feet getting bigger
How to treat gigantism and agromegaly? (2)
Surgery to remove tumour
Somatostatin analogues
Why somatostatin analogues to treat acromegaly?
Somatostatin aka GHIH is a hormone that inhibits GH
Is there height/ longitudinal growth in acromegaly?
No
Unusually small stature is to do with hormones. What are the 5 reasons?
Deficiency of GHRH
Deficiency of GH
Genetic mutations of GH receptor (can’t respond to growth signal)
Precocious puberty- sec hormones cause long bones to fuse early
Hypothyroid dwarfism (loss of permissive effect of TH on GH)
Why does injury and disease stunt growth?
Because if protein catabolism (glucocorticoid effects)
Pathology of Graves’ disease
It’s hyperthyroidism, where the individual produces antibodies that mimic the action of TSH
Levels of TSH and T4 in graves?
High T4
low TSH (bc of negative feedback)
Why is there muscle weakness/ weight loss in hyperthyroidism?
There’s increased protein catabolism
Both Hashimoto’s disease and graves is autoimmune. Difference?
Hashimoto = autoimmune attack of the thyroid gland
Graves = autoimmune, replication of TSH hormone
Does iodine deficiency cause hyperthyroidism or hypothyroidism?
Hypothyroidism
Both hypo and hyper thyroid Ian is accompanied by significant enlargement of the thyroid gland. What causes this?
“Goitre”
Caused by an increase in trophies action of TSH on thyroid follicular cells, or over-activity as a result of autoimmune disease like graves therefore hypertrophy
What’s the most common cause of congenital adrenal hyperplasia, resulting in deficiency of aldosterone and cortisol?
Defects in the 21-hydroxylase enzyme that is required to synthesise both aldosterone and cortisol
What does deficiency in aldosterone and cortisol result in?
Associated disruption of sale and glucose balance
Why are babies born with deficiency in 21 hydroxylase (leading to deficiency in aldosterone and cortisol) lead to being born with malformed genitalia?
Because all the cholesterol in the adrenal cortex ends up getting channeled into the production of the sex hormones.
So exposed to much higher concentrations of sex hormones than others is.
How quickly do babies become ill after birth when they have a deficit in 21-hydroxylase ?
Like very very ill within days
Hypersecretion of cortisol is what disorder?
Cushing’s
Cushing’s disease Vs Cushing’s syndrome?
Both = hypersecretion of cortisol
Disease = tumour in adrenal cortex -directly more cortisol
Syndrome = tumour in pituitary gland - hyper secreting ACTH
If Cushing’s disease is a rise in cortisol, which has catabolic action, why is there a distribution of fat ie moon face and on the neck?
There are wasting of extremities, but for unknown reasons, fat is redistributed to face and trunk. So far on the trunk, but still thin arms and lega
Hyposecretion of cortisol is associated with what disease?
Addison’s disease
Pathology of Addison’s disease?
Autoimmune destruction of adrenal cortex
How to treat addisonian crises/ adrenal crises?
What is addisonian crises/ adrenal crises?
low cortisol
Affect of alcohol, caffeine and lack of sleep on the hypothalamo-pituitary-adrenal axis?
Disinhibits. Removes negative feedback , causing an increase in cortisol release.
Why does stress lead to further infection
Because stress leads to more cortisol being released, which suppresses the immune system.
Why are you cold with hypothyroidism?
Often beta blockers are used in the management of hyperthyroidism. When is this contraindicated?
Asthma
What drug for weight management?
Orlistat
What does orlistat do?
Help with weight management, by inhibiting pancreatic and gastric lipases, so inhibits fat absorption
Usually prescription for orlistat?
Usual prescription does 120mg 3 times daily
If you eat something fatty, and take orlistat?
Very fatty diarrhoea
