Endocrine CBL Flashcards
Presentation of T1DM
Onset usually in childhood
Usually lean
Typically acute - polyuria, polydipsia, weight loss
Ketosis prone
Presence of auto antibodies - islet cells, insulin
C peptide low or undetectable
Autoimmune polyendocrine syndrome type 2
Triad of addisons, Al thyroiditis and T1DM
Common in females
Presents in adulthood
Associated with - coeliac, pernicious anaemia, alopecia
DKA triad
Hyperglycaemia
Acidosis
Ketonuria
Clinical signs of DKA
Abdo pain
Kussmauls breathing
Smell of ketones in breath
Diabetes fasting and random glucose cut diagnostic criteria?
Fasting >7
Random >11.1
HbA1c of 48mmol/mol (6.5%) recommended cut off
How does insulin deficiency lead to DKA?
Insulin deficiency = excess mobilisation of FFAs from adipose tissue, providing substrate for ketone production from the liver.
Ketones are excreted by kidneys and buffered in blood but this system eventually fails and acidosis develops.
Hyperglycaemia also occurs as the liver produces glucose from lactate and alanine.
Osmotic diuresis causes hypovolaema
Name 3 ketones
B hydroxyl butyrate, acetoacetate, acetone
Possible causes of DKA not with new T1DM?
Non compliance with insulin
Infection
Pregnancy
MI
How should DKA be managed?
Insulin and fluids - monitor electrolytes (particularly potassium)
Name 5 elements to be considered when educating a newly diagnosed T1DM?
Never stop insulin Sick day rules Recognising signs of hypoglycaemia Smoking Driving regulations (inform DVLA) Exercise Planning a pregnancy
Typical features of T2DM
Over 30 Gradual onset 25-30% have retinopathy at presentation Overweight/obese Autoimmune markers tend to be negative
Define type 2 DM
Chronic, progressive metabolic disorder characterised by insulin resistance and impaired secretion
Mx of diabetic cardiovascular disease
Risk factor modification - smoking, dyslipidaemia, hypertension, hperglycaemia
Lower BP - ACE, calcium channel blocker or thiazide diuretic
Multidisciplinary team members in diabetes?
Optician
Podiatrist
Diabetic nurse specialist
Dietician
Risk factors for gestational diabetes mellitus?
BMI Previous birth weight (4.5kg or more) Previous GDM Family history of diabetes Minority ethnic origin
Diagnosis of GDM
Fasting plasma glucose >5.11 or
two hours after OGTT >8.5
Symptoms of thyrotoxicosis
Weight loss Increased appetite Tremor Polyuria Weakness, fatigue Insomnia Anxiety Change in heat preference - cold not hot
Most sensitive indicator of thyroid dysfunction?
Thyroid stimulating hormone (TSH) - cant be used in px with pituitary disease as they don’t produce TSH
Sick euthyroidism
Low TSH, low free T3 and sometimes low T4
Amiodarone and its effects on TFTs
1) inhibits T4-T3 conversion = mild raise in TSH
2) can induce hypothyroidism
3) Can induce hyperthyroidism - e.g. destructive thyroiditis
Px on amiodarone have High normal T4, low normal T3 and initially high TSH
Px presents with
Raised T4
Low T3
Initial high TSH
Diagnosis?
Amiodarone effects
Define hyperthyroidism and thyrotoxicosis?
Thyrotoxicosis is the syndrome resulting from excessive free thyroxine (t4) and free tri-iodothyronine (t3)
Hyperthyroidism refers to thyroid overactivity resulting in thyrotoxicosis
Causes of thyrotoxicosis
Primary -
Graves
Toxic multinodular goitre
Toxic adenoma
Secondary -
TSH secreting pituitary adenoma
Gestational thyrotoxicosis
Thyroid hormone resistance syndrome
Investigations to diagnose cause of thyrotoxicosis?
Thyroid autoantibodies -
Anti TPO antibodies
Anti TSH receptor antibodies (most reliable test for graves)
Nuclear imaging
Nuclear imaging in diagnosing thyrotoxicosis
Thryoid scintigraphy scanning is useful when antibody testing is negative, a nodule is palpable
Patterns -
Diffuse uptake with suppression of background activity (graves)
Irregular uptake - multinodal goitre
Hot nodule - toxic adenoma
Reduced uptake - thyroiditis
Tx of graves disease
Antithyroid drugs -
B blockers
Carbimazol and propylthiorucal (PTU)
Radioactive iodine
Surgery
Carbimazole and propylthiouracil (PTU) MOA
Inhibit iodide organification by thyroid peroxidase = reduces T3 and T4 levels
Carbimazole is usually used, PTU if pregnant.
2 regimens -
1) Reducing regimen started higher then reduced once px euthyroid
2) block and replace - commence carbimazole then when euthyroid add thyroxine
Features specific to graves eye disease
Exophthalmos - Lid lag and lid retraction (NOT ONLY SPECIFIC TO GRAVES) Periorbital oedema Proptosis Grittiness and redness Opthalmoplegia
Factors increasing risk of developing opthalmopathy
Smoking
Male sex
Radioactive iodine treatment
What features would elicit an urgent opthalmological referral in thyroid disease?
Blurred vision Poor vision Severe conjunctival pain Poor colour vision Recent or rapid changes in vision
Tx of graves opthalmology
Grittiness - artificial tears
Eyelid - tape eyelids at night to avoid corneal damage
Proptosis - steroids
MODY
Maturity onset diabetes of the young
Genetic mutation, autosomal dominant, disrupts insulin production
