High-yield points in endocrinology p1

UK MRCP
#1

HIGH-YIELD POINTS IN ENDOCRINOLOGY P1

  • Patients on long-term steroids should have their doses doubled during intercurrent illness.
  • Acromegaly: increased sweating is caused by sweat gland hypertrophy.
  • Subclinical hyperthyroidism: supraventricular arrhythmias and osteoporosis
  • Hashimoto’s thyroiditis = hypothyroidism + goitre + anti-TPO
  • Insulinoma is diagnosed with supervised prolonged fasting.
  • Glitazones/thiazolidinediones are agonists of PPAR-gamma receptors, reducing peripheral insulin resistance.
  • Radioiodine treatment may lead to the development / worsening of thyroid eye disease in up to 15% of patients with Grave’s disease.
  • Diabetes mellitus - HbA1c of 6.5% or greater is now diagnostic (WHO 2011)
  • Infertility in PCOS - clomifene is superior to metformin
  • The diagnostic test for acromegaly is an oral glucose tolerance with growth hormone measurements.
  • The primary mode of action of orilistat is to inhibit pancreatic lipases, which in turn will decrease the absorption of lipids from the intestine.
  • Hypercholesterolaemia rather than hypertriglyceridaemia: nephrotic syndrome, cholestasis, hypothyroidism.
  • Cushing’s disease (pituitary tumour) is the most common, non-iatrogenic, cause of Cushing’s syndrome.
  • The first-line treatment in remnant hyperlipidaemia (dysbetalipoproteinaemia) is fibrates.
  • In the presence of an ACE inhibitor prescribed for hypertension, significant hypokalaemia is very likely to be related to Conn’s syndrome.
  • Hashimoto’s thyroiditis is associated with thyroid lymphoma.
  • Diabetes diagnosis: fasting > 7.0, random > 11.1 - if asymptomatic need two readings
  • Flushing, diarrhoea, bronchospasm, tricuspid stenosis, pellagra → carcinoid with liver mets - diagnosis: urinary 5-HIAA
  • Hypo-, not hypertension, is seen in carcinoid syndrome secondary to serotonin release.
  • Patients with impaired glucose tolerance (IGT) are more likely to develop diabetes than patients with impaired fasting glycaemia.
  • Rapid weight gain, episodic (typically early in the morning) sweating, double vision: Insulinoma
  • An isolated hypertriglyceridaemia in the presence of significant cardiovascular risk factors, in a patient not currently on a statin, should be managed with a statin.
  • Isolated hypertriglyceridaemia in the absence of significant cardiovascular risk factors should be managed with a fibrate.
  • Insulin and GLP-1 fixed-dose combinations are associated with increased risk of hypoglycaemia. Rates of confirmed hypoglycaemia (<3.1 mmol/l), run at between 1.8 and 3.5 per patient year of exposure.
  • Cushing’s syndrome - hypokalaemic metabolic alkalosis
  • Insulin stress tests are used to differentiate Cushing’s from pseudo-Cushing’s.
  • Whilst anti-thyroid peroxidase (anti-TPO) antibodies are seen in 90% of Hashimoto’s disease, they are also seen in 75% of patients with Graves’ disease.
  • In primary atrophic hypothyroidism, a TSH value between 0.5 to 2.5 mU/l is now considered preferable.
  • MODY is autosomal dominant diabetes mellitus which often presents for the first time in young slim individuals without symptoms of polyuria and polydipsia. Insidious onset with recurrent balanitis is usual. It’s important to recognise the diagnosis because many patients with MODY (including those with the HNF-1 alpha form of the disease) can be managed with sulphonylureas for many years before needing to start insulin therapy.
  • Primary hypoparathyroidism is usually the first endocrine manifestation of type 1 autoimmune polyendocrinopathy syndrome (APS). The contrast to multiple endocrine neoplasia (MEN), where hyperparathyroidism is a common finding, should be noted.
  • Polycystic ovarian syndrome - ovarian cysts (not LH:FSH ratio) are the most consistent feature
  • Obesity - NICE cutoffs for bariatric surgery referral
     with risk factors (T2DM, BP etc): > 35 kg/m^2
     no risk factors: > 40 kg/m^2
  • Gitelman’s syndrome: normotension with hypokalaemia
  • Pretibial myxoedema is not seen in other causes of thyrotoxicosis and points towards a diagnosis of Graves’ disease.
  • EuDKA is an important to recognise side effect of SGLT2 inhibitors and should be thought of in any patient with an unexplained raised anion gap acidosis and normal blood sugar level who is on one of these drugs.