Endocrinology Flashcards
How do you tell the difference between an ischaemic and neuropathic foot ulcer?
Plantar location or sites of pressure makes neuropathic more likely
Cold, pulseless, hairless makes ischaemic more likely
Charcot joint is caused by neuropathy
HOw would you investigate a diabetic foot?
Swab ulcer
FBC, U&E, CRP, fasting lipids, TFT, HBA1c, urine ACR
Doppler to assess vascular supply
PLain foot XR for osteomyelitis
MRI is often needed to exclude osteomyelitis
COnsider bone biopsy if ongoing infection
How would you treat a diabetic foot?
Orthotics- pressure relieving
Appropriate treatment for PVD eg revascularisation
Broad spectrum antibiotics covering staphs, streps and anaerobes if any suggestion of infection and adjust according to microbiology
Surgical review
Optimise glycaemic control
What are the symptoms of diabetes?
Thirst, polyuria, polydipsia
Weight loss
Blurred vision
Recurrent infections
What conditions are assoc with neuropathic ulcers?
Diabetes Leprosy Tabes dorsalis Amyloidosis Alcoholic neuropathy Hereditary neuropathies (charcot-marie-tooth) Drugs Deficiencies eg B12, thiamine
How would you manage an obese patient with T2DM
MDT support- dietician, exercise advice
Drugs: metformin, orlistat, exenatide/liraglutide- incretin (GLP1) mimetics which stimulate insulin secretion, slow emptying of stomach and inhibit production of glucose by liver, also suppress appetite and aid weight loss
Surgery: gastric band or bypass
What are the causes of secondary diabetes?
Steroid use PCOS Hyperthyroidism Chronic pancreatitis Cystic fibrosis Haemochromatosis Acromegaly Phaeochromocytoma Cushings syndrome Glucagonoma
What are the symptoms of autonomic neuropathy?
Dysregulated sweating including gustatory Constipation with bacterial overgrowth Diarrhoea Postural hypotension Bladder and erectile dysfunction Cardiac dysarythmias
What different types of neuropathy are seen in diabetes?
Progressive sensory Mononeuritis eg CN Pressure palsies Amyotrophic Autonomic
What are the steps of intensification in managing diabetes?
- Metformin alone (if GI side effects then try modified release) (SGLT-2 i if metformin not tolerated)
- Metformin + DPP-4 inhibitor or
Metformin + pioglitazone (C/I in heart failure, hepatic impairment, bladder cancer) or
Metformin + sulfonylurea - Metformin + DPP-4 inhibitor + Sulphonylurea or
Metformin + pioglitazone + sulphonylurea or
Insulin therapy - Insulin therapy
Other options
GLP-1 mimetic if:
1. have a BMI of 35 kg/m2 or higher (adjust accordingly for people from black, Asian and other minority ethnic groups) and specific psychological or other medical problems associated with obesity or
2. have a BMI lower than 35 kg/m2 and
for whom insulin therapy would have significant occupational implications or
weight loss would benefit other significant obesity-related comorbidities
What is a DPP4-i and give some examples?
Block dipeptidyl peptidase 4 (DPP4) which would normally inactivate GLP-1 so increasing amount GLP-1 Promote insulin release Inhibit glucagon release Sitagliptin Vildagliptin
How would you diagnose T2DM?
random ≥11.1 mmol/L or fasting ≥7 mmol/L WITH symptoms
In asymptomatic people with an abnormal random plasma glucose, two fasting venous plasma glucose samples in the abnormal range (≥7 mmol/L)
HBA1c= 48mmol/L (6.5%)
What are the differential diagnosis of hyperthyroidism and what in the history may you need to enquire about?
Most common Graves disease (ask about autoimmune history and eye sight) and Toxic multinodular goitre
Other:
Thyroiditis -ask about neck pain and recent childbirth
Drug induced- ask about iodine/contrast, amiodarone, lithium, interferon therapy
Gestational thyrotoxicosis
How would you treat hyperthyroidism?
Correcting hyperthyroidism
- Carbimazole and propylthiouracil
- Titration: initial dose of carbimazole of 30-40mg tapered down over 4-8weeks to maintenence of 5-10mg
- Block and replace: 40mg carbimazole used initially then add 100mcg levothyroxine when free T4 is in normal range (after 4 weeks usually)
Treatment course around 18months
Warn about rash and risk of agranylocytosis
Radio-iodine- likely to result in long term hypothyroidism, may exacerbate eye disease
Surgery- may result in long term hypothyroidism, hypoparathyroidism, hoarse voice
Treat symptoms: beta blocker
How is proptosis quantified?
Hertel’s exophthalmometer, readings >20mm = proptosis
How would you manage a patient with Graves opthalmopathy?
- stop smoking
- lubricating eye drops and raising head of bed
- essential to keep euthyroid (raised TSH or thyroid hormone are assoc with worse clinical outcomes)
- Active eye disease (indicated by soft tissue signs- scleral injection, chemosis, periorbital oedema) may require immunosuppresion (steroids)
- Diplopia or significant proptosis need opthalmological assessment- diplopia may need prisms, worsening may require IV steroids, orbital decompression/irradiation
- Any change in visual acuity or colour vision needs immediate opthalmological input and high dose iV steroids, immunosuppresion, irradiation or decompression of orbit
What do you knwo about the use of radio-iodine in patients with graves eye disease?
Radio-iodine may exacerbate thyroid eye disease and is contraindicated in patients with active or severe opthalmopathy. It can be used in patients with mild eye disease with steroid cover.
It can occasionally precipitate thyroid eye disease
Which types of thryoid disease have high uptake on thyroid uptake scans and which have low uptake?
High uptake:
- Graves disease- diffuse
- Toxic multinodular goitre- focal uptake
- Toxic adenoma (focal uptake)
Low uptake:
- thyroiditis
- iodine/amiodarone induced hyperthyroidism
- factitious: people taking thyroxine
Non-functioning nodules are more likely to be malignant
How would you manage a patient with toxic multinodular goitre?
Radioactive iodine: may cause transient enlargment of goitre before reduction
Surgery: particularly compressive symptoms
Anti-thyroid drugs are not a long term option for toxic multinodular goitre as thyrotoxicosis recurs when treatment stops.
If TSH is normal and patient is unsuitable for radioiodine or surgery then small doses of levothyroxine can be given to suppress TSH levels and reduce chance of goitre enlarging- not very effective
What are the indications for treatment in non-toxic multinodular goitre?
Compression and obstruction- trachea, oesophagus, venous outflow
Cosmetic
Marked intra-thoracic extension
Explain the difference between hot and cold nodules
Cold nodule: diminished uptake when compared to surrounding thyroid tissue (5-10% malignant)
Hot nodule: increased uptake with suppressed uptake in thyroid tissue (hot nodules are never malignant)
What is the differential diagnosis of a solitary thyroid nodule?
Thyroid cyst Thyroid adenoma Thyroid carcinoma Metastatic cancer Lymphoma Sarcoma Parathyroid cyst
What are symptoms of hypothyroidism?
Dry skin and hair loss Cold intolerance Constipation Peripheral oedema Tingling and paraesthesia in hands (carpal tunnel) Neck swelling Menstrual disturbance Snoring and early morning headache (assoc OSA) Skin pigment changes Depression
What are the signs of hypothryoidism?
Bradycardia Coarse, brittle hair Coarse facial features Periorbital oedema Jaundice Macroglossia Goitre Loss of lateral eyebrows Hyporeflexia Oedema- non pitting (myxoedema) or pitting
How should you finish your examination of thyroid>
Ask patient to stand up with their arms folded in front of them (proximal myopathy)
Then kneel on chair to examine ankle jerks
Remember to look for tremor at start of examination
What are the causes of hypothyroidism?
Hashimotos thyroiditis (most common TPO Ab)
After thyroid ablation, surgery or radioiodine
Thyroiditis: post transient hyperthyroid stage
Drugs: amiodarone, lithium, interferon, anti-thyroid drugs
Tell me about hypothyroidism and pregnancy?
Hypothyroidism particularly in the 1st 12 weeks of pregnancy has been shown to have detrimental effects on foetal neurodevelopment.
Thyroid hormone requirements rise substantially in pregnancy with dose range increments 25-50%. Should have TFTs checked every trimester and aim for TSH 0.5-2.0. After delivery can return to normal dose.
Tell me how you would initiate levothyroxine replacement therapy in an elderly patient with hypothyroidism
They can often have been hypothyroid for some time before diagnosis as symptoms can be attributed to aging. They may have co-existing IHD and is therefore prudent to start with low initial dose of 12.5-25mcg levothyroxine and titrate up cautiously but 25mcg every 2-4weeks
What is myxoedema coma?
Severe form of hypothyroidism resulting in altered mental status, hypothermia, bradycardia and hyponatraemia. Cardiomegaly, pericardial effusion and ascites may be present.
May be consequence of long term hypothyroidism or precipitated by an insult eg infection.
What are the symptoms of acromegaly/what would you ask in a history?
Sweating
SYmptoms of hyperglycaemia- polyuria/polydipsia
Hypertension
Daytime somnolence, early morning headaches (OSA)
Change in bowel habit/rectal bleeding
Trouble with peripheral vision/bumping into obejects
Weakness- proximal
Joint pains- hips and knees
What are the signs of acromegaly
Large, doughy spade like hands Sweaty (implies active disease Oedema Absence of rings Carpal tunnel syndrome BM testing marks Goitre Kyphosis (due to osteoporotic #) Proximal muscle weakness Oedematous eyelids Bi-temporal hemianopia Prominent supra-orbital ridges Marked enlargement of nose and ears Proganthism Macroglossia Widened interdenticular spaces Surgical scars- transphenoidal/transcranial Gynaecomastia Displaced apex beat (cardiomegaly) Acanthosis nigricans Skin tags
