Endocrinology Flashcards
Symptoms and signs of Hyperthyroidism
Symptoms
- Nervous, anxious, increased perspiration
- Heat intolerance, hyperactivity
- Palpitations
- Diarrhoea
- Wieght loss despire increase in appetite
- oligomenorrhoea
Signs
- Tachycardia or atrial arrhythmia
- Systolic hypertension - wirth wide pulse pressure
- Warm, moist skin
- Lid lag
- Hand tremor
- Muscle weakness
Graves Disease
- Ophthalmopathy –> Exophthalmos, periorbital oedema –> lid lag, lid retration, diplopia
- Goitre
- Pretibial myxedema (hyaluronic acid in the subcutis of the shins)
Causes of hyperthyroidism
Primary hyperthyroidism
- Graves Diseae
- Hyperfunctional Multinodular Goitre
- Hyperfuctnional thyroid adenoma (most carcinomas are not functional)
- Hashitoxicosis (early phase of hashimotos)
- Iodine overload
- Drugs - lithium, thyroixine
- Paraneoplastic syndrome (germ cell tumour e.g. teratoma)
Secondary hyperthyroidism
- Pituitary adenoma –> increase production of TSH
How do you differentiation secondary and primary hyperthyroidism through investigations
- Serum free T4, T3 –> elevated in hyperthyroidism
- TSH –> suppressed in primary disease, not suppressed in TSH mediated disease (secondary)
What are the investigations for thyroid disease
Blood tests
- Free T4, T3
- TSH
- Serum thyroglobulin levels (Tg) –> low levels if exogenous thyroid hormone
- Serum thyroid antibodies
i) Thyroid receptor antibodies –> Grave’s Disease
ii) Thyroid peroxidase –> Hashimotos, Graves
iii) Thyroglobulin antibodies –> Hashimotos, Graves, T1DM, thyroid cancer
Imaging
- Thyroid U/S
- Thyroid scintigraphy (nuclear medicine scan)
- -> Normal thyroid - diffuse uptake of RAI
- -> Graves - enlarged gland with increased RAI uptake
- -> Toxic MNG - multiple nodules both hot and cold
- -> adenoma - hot nodule
Treatment of hyperthyroidism
First line of Graves and MNG:
- Carbimazole 10-45mg orally, daily 2-3 doses (inhibits thyroperoxidase)
Second line of Graves and MNG:
- Propylthiouracil 200-600mg orally, daily 2-3 doses (inhibits thyroperoxidase and periopheral deiodination of T4)
Sympatheric NS treatment e.g. tremor, tachycardia, eyelid retraction
- Propranolol 10mg orally
Other treatments:
- Thyroidectomy and replace T4
- Irradiate gland and replace T4
- Potassium iodide (prevent peripheral deiodination of T4)
Adverse effect of thyroid drugs –> agranulocytosis
Causes of hypothyroidism
Primary
- Hashimoto’s - autoimmune thyroiditis
- Iodine deficiency/ Maternal def.
- Surgery/ irradiation
Secondary
- pituitary adenoma
- pituitary apoplexy
- Sheehan’s syndrome
- head trauma
Symptoms and signs of hypothyroidism
- Weakness, lethargy
- Weight gain
- Dry skin
- cold intolerance
- Constipation
- Depression
- Ammenorrhoea
- Facial oedema
- Bradycardia
- Goitre
Two serious complications of hypothyroidism in childhood and adulthood
Childhood –> Cretinism (Impaired development of skeleton and CNS)
- Short stature, course facial features, protruding tongue and severe mental impairment
Adulthood –> Myxoedema
- Slowing of physical and mental activity
Treatment of hypothyroidism
Thyroxine (T4) 30-100ug/day
*T3 is available as IV formulation, for rapid treatment of life threatening hypothyroidism
Adverse effects - sinus tachycardia, arrhythmias, angina, restlessness, tremor
Causes of hypernatraemia
Hypovolemic
- Dehydration (poor flood intake, diarrhoea)
- Diuretics, osmotic diuretics (hyperglycaemia, uraemia)
Euvolemic
- Diabetes inspidus
Hypovolemic
- Primary hyperaldosteonism
- Cushing’s syndrome
- Iatrogenic - excess NaCl
Clinical features of sodium imbalance
Mild
- Anorexia
- N + V
- Headache
- Muscle cramps
Moderate
- Muscle weakness
- Lethargy
- Confusion
Severe
- Seizures
- Altered consiousness
Symptoms also depend on the onset of sodium imbalance
- Acute onset (<48hrs) usually symptomatic event even with mild sodium derangements
Subacute (>48hrs) usually asymptomatic unless severe derangements are present
Orthostatic hypotension, oliguria, impaired thirst
Investigations and results for hypernatraemia
- Serum sodium concentration - increased
- Serum osmolarity - increased
- Haematocrit - increased in hypovolaemia, dehydration
- Urinalysis - osmolarity > 800mOsmol/kg in extra-renal loss and < 800mOsmol/kg in renal loss
Treatment of hypernatraemia
- Treat underlying cause
- Patients with serum sodium values <>160mEq/L require intensive care
- Careful correction of sodium levels: maximum correction within 24 hours is 10mEq/L (rate of correction: 0.5-1mEq/L per hour)
- Effects of rapid correction - Rapid decrease in serum sodium à risk of cerebral oedema
Correct free water deficit
- Mild hypernatraemia à oral rehydration
- Moderate to severe hypernatraemia à hypotonic saline or 5% dextrose
Hypovolaemia hypernatraemia
- Fluid resuscitation
- Once adequately resuscitation à correct free water deficit
Euvolemic hypernatremia
- Correct free water deficit
Hypervolemic hypernatraemia
- Loop diuretic + 5% dextrose
Causes of hyponatraemia
Investigations in hyponatraemia
Blood tests
- Serum Sodium
- Serum osmolality
- Haematocrit
- ¯ - possibly fluid overload
- - hypovolaemia, dehydration
Urine examination
- Urine sodium concentration
- >20Eq/L implies renal sodium loss
- <20Eq/L implies extra renal sodium loss
Treatment for hyponatraemia
- Treat underlying cause
- Patients with serum sodium values < 120mEq/L require intensive care
- Careful correction of sodium levels: maximum correction within 24 hours is 10mEq/L (rate of correction: 0.5-1mEq/L per hour)
- Effects of rapid correction - Rapid increase in sodium levels à risk of central pontine myelinolysis
Hypovolemic hyponatraemia
- Mild – moderate –> normal saline
- Severe symptoms –> hypertonic saline
Euvolemic hyponatraemia
- Mild – moderate –> fluid restriction
- Severe à hypertonic saline
Hypervolaemia hypnatraemia
- Mild – moderate à fluid restriction +/- loop diuretic
- Severe –> isotonic saline
Symptoms of T1DM
- polydipsia
- polyuria
- weight loss
- blurred vision
- nausea and vomiting
- abdominal pain
- lethargy
Acute complications of T1DM and T2DM
- DKA –> T1DM
- Hypoglycaemia –> over treatment
- Hyperglycaemic hyperosmotic state –> T2DM
Chronic complications of Diabetes
1) Predisposition to infection
2) Microangiopathy
- Diabetic nephropathy - decreased GFR + albuminuria
- Neuropathy - peripheral and autonomic
- Retinopathy - proliferative and non-proliferative
3) Macroangiopathy
- CVD, cerebrovascular disease
- PAD
- HTN
- Diabetic foot
Investigations for diabetes
- Fasting and random plasma glucose
- Fasting glucose - (>7mmol/L – should be between 3.5-5.5mmol/L)
- Casual - 11.0mmol/L
- Plasma or urine ketones
- HbA1c
- >6.5%
iv. Urinalysis
Treatment for T1DM
- Diet and Exercise - Low GI foods
- Monitoring - finger-prick blood test, specialist
- Insulin
First line –> Basal-bolus regiment - Bolus - Aspart 100 units/mL
- Basal - Glargine 100 units/mL
Total insulin 0.5-0.8units/kg for an adult
Side effects –> hypoglycaemia, weight gain, injection site scaring
Can also add sotaglifozin –> SGLT1/2 inhibitor
Causes of DKA
- Insufficient insulin replacement
- Under administration – insulin pump failure, forgotten injection, non-compliance
- Undiagnosed, untreated diabetes
- Increased insulin demand
- Stress –> infection, illness, surgery, trauma, MI
- Drugs etc. –> Glucocorticoid therapy, cocaine use, alcohol abuse
Symptoms and signs of DKA
Symptoms
- Nausea and vomiting
- Fatigue
- Abdominal pain
- Ketotic breath
- Laboured Breathing
- LOC
- Polydipsia and polyuria
Signs
- Dry mucus membranes
- Decreased skin turgor
- Tachycardia, tachypnoea
- Abdominal tenderness
Investigation results in DKA
- Plasma glucose - elevated
- ABG and electolytes
- pH < 7.3
- Increased pO2, K+
- decreased pCO2, bicarbonate, K+ - Capillary or serum ketones - elevated
Management of DKA
- Fluids - correct fluid loss and dehydration
- IV insulin - correction of BSL and ketone
- K+ correction and other electrolytes
Causes of Hypoglycaemia
Diabetics
- Too much insulin
- Delaying or missing a meal
- Unplanned physical activity
- Drinking alcohol
Non-diabetic
- Growth hormone deficiency and adrenal deficiency
- Endogenous excess of insulin – insulinoma
Symptoms of hypoglycaemia
- shaking, trembling
- sweating, paleness
- hunger
- light headedness, headache, dizziness
- pins and needles around mouth
- LOC
- confusion
Treatment for hypoglycaemia
Mild –> sweat snack
Severe –> glucose 15-20g IV or glucagon 0.1-1mg IM/ SC
Treatment of type 2 diabetes
- 1st line - Metformin - CrCL > 60mL/min - 500mg orally BD, increasing dose up to 2g daily
- Add on Sulfonylurea - gliclazide 40mg orally OD or BD up to 320mg
- Consider bariatric surgery
Non-Pharm
- lifestyle measures - dieat and exercise
- reduce CVD risk factors
What is hyperglycaemic hyperosmotic state?
A serious metabolic complication of diabetes characterised by severe hyperglycaemia, hyperosmolar, and volume depletion in the absence of severe ketoacidosis, occurs most commonly in older people with T2DM. the result is severe dehydration due to severe osmotic diuresis due to hyperglycaemia.
Investigations for hyperglycaemic hyperosmotic state
- Plasma glucose – elevated
- Serum ketones – not elevated
- Serum osmolality – elevated
- Urinalysis – positive for glucose, positive for leukocytes and nitrates in absence of infection, negative or only mildly positive for ketones
