Endocrinology Flashcards
Goitre
What is the differential diagnosis of a neck mass?
Mnemonic SLC VN (Slick V Neck)
- Salivary: Sialadenitis, Salivary gland tumour
- Lymphadenopathy: Infectious, Malignant, Granuomatous (sarcoidosis, tuberculosis)
- Congenital: Thyroglossal cyst, Branchial anomalies
- Vascular: Carotid artery aneurysm, Carotid body tumour, Jugular vein thrombosis
- Neurogenic: Neural crest derivatives e.g. Schwannoma, Neurofibroma, Malignant peripheral nerve sheath tumours
Goitre
What is the differential diagnosis of a retrosternal mass?
- Goitre
- Thymoma
- Lymphoma
- Germ cell tumours e.g. teratomas, seminoma
Goitre
What are the causes of a goitre?
- Simple goitre (iodine deficiency)
- Physiological goitre (puberty, pregnancy)
- Grave’s disease
- Thyroiditis e.g. Hashimoto’s, De Quervain’s, Infectious, Radiation, Post-partum
- Thyroid cyst
- Thyroid cancer
- Toxic adenoma
- Single palpable nodule in multinodular goitre
Assessment of Thyroid State
What are the causes of hyperthyroidism?
- Grave’s disease
- Toxic adenoma
- Toxic multinodular goitre
- Thyroiditis
- Drugs e.g. iodine, amiodarone, lithium
- TSH secreting pituitary tumour (TSHoma)
- Trophoblastic disease & Germ cell tumours
Assessment of Thyroid State
What are the causes of hypothyroidism?
- Hashimoto’s thyroiditis
- Idiopathic atrophy
- Iatrogenic: Radioiodine treatment, Thyroidectomy
- Iodine deficiency
- Antithyroid drugs; lithium, amiodarone
- Thyroiditis (all can cause transient hypothyroidism)
- Hypothalamic or Pituitary disease
Cushing’s Syndrome
What are the causes of Cushing’s Syndrome?
>ACTH dependent Cushing's syndrome: -Cushing's disease (pituitary adenoma) -Ectopic ACTH secretion (SCLC, carcinoid tumour) >ACTH independent CUshing's syndrome: -Exogenous steroid administration -Adrenocortical adenomas/carcinomas
Acromegaly
What are the complications of acromegaly?
- Hypertension
- Impaired glucose tolerance (diabetes)
- Cardiomegaly
- Visual field defects
- Tumours e.g. colonic polyps, uterine leiomyomata
- Entrapment neuropathies e.g. carpal tunnel syndrome
- Arthritis
Addison’s Disease
What are the causes of primary adrenal failure?
- Autoimmune adrenalitis
- Tuberculosis
- Bilateral adrenalectomy
- Haemorrhagic infarction e.g. Waterhouse-Friedrichsen syndrome (meningococcal sepsis), Bacterial sepsis, Thromboembolism disease, Thrombophilia, Antiphospholipid syndrome, Anticoagulation
- Adrenal metastases
- Infections e.g. HIV (CMV adrenalitis), Disseminated fungal infection
Hypopituitarism
What are the causes of pituitary failure?
- adenoma, craniopharyngioma, cyst, metastases
- Iatrogenic e.g. Pituitary surgery or radiotherapy
- Empty sella syndrome (surgery, radiotherapy, infarction)
- Pituitary Infarction e.g. Sheehan’s syndrome following postpartum haemorrhage
- Pituitary apoplexy (sudden haemorrhage into pituitary gland)
- Infiltrative disease e.g. sarcoidosis, haemochromatosis
- Trauma, Subarachnoid haemorrhage
Addison’s Disease
What are the differential diagnoses of skin pigmentation?
- Addison’s disease
- Nelson’s syndrome
- Ectopic ACTH syndromes
- Haemochromatosis
- Jaundice
- Uraemia
- Porphyria cutanea tarda
Gynaecomastia
What are the causes of gynaecomastia?
- Cirrhosis
- Hypogonadism (primary or secondary)
- Androgen insensitivity syndromes (testicular feminization syndrome)
- Tumours (testicular, adrenocortical ectopic HCG secreting)
- Drugs (digoxin, spironolactone, cyproterone)
- Chronic renal failure
- Thyrotoxicosis
Neurofibromatosis
What are the clinical features of neurofibromatosis?
Name three causes of hypertension associated with neurofi bromatosis?
(pocketbook)
> Clinical Features:
-NF-1 (peripheral): Cafe-au-lait spots, Neurofibromata, Axillary/Inguinal freckling, LIsch nodules, Pulmonary fibrosis, Restrictive cardiomyopathy
-NF-2 (central): Acoustic neuroma (affecting CN 5-8), Meningioma, Ependymoma, Optic glioma (which also occur in 15% of NF-1).
Diagnostic Criteria:
-NF-1: 2 or more of >6 cafe-au-lait spots, >2 neurofibromata, >2 lisch nodules, axillary/inguinal freckling, first degree relative
-NF-2: bilateral VIII nerve involvement, first degree relative
————-
• Renal artery stenosis
• Phaeochromocytoma
• Coarctation of the aorta.
In hypopituitarism, in what order does hormone loss progress?
1) GH and FSH/LH
2) TSH
3) ACTH
How would you investigate a goitre / hyperthyroidism?
>TSH; Free T3, T4 >TRAb (or TSI) - TSH receptor TRAb's (TSI thyroid stimulating immunoglobulin in graves; sometimes in TMNG; sometimes a blocking TRAb in Hashimotos) >Thyroid U/S >Thyroid uptake scan
How would you investigate hypothyroidism?
> TSH (high); Free T4/T3
Anti TPO (thyroid peroxidase) and Anti thyroglobulin
-Thyroid peroxidase TPOAb (involved in Hashimotos and post-partum thyroiditis; some overlap in Graves)
-Thyroglobulin TgAb (released in both destruction Hashimoto and disordered growth of Graves)
Features of acromegaly?
- hand shape: spade
- axilla acanthosis nigricans
- facies: frontal bossing
- macroglossia
- visual field defects
- CCF, Organomegaly
- signs of hypothyroidism
What investigations for acromegaly?
IGF1 (increased)
OGTT (should suppress GH level)
MRI
How to diagnose diabetes?
Fasting BSL > 7
Or
OGTT > 11
IGT: OGTT BSL 7-11
What class of OHG is metformin? How does it work? What are the side effects?
- biguanide
- increases insulin sensitivity, decrease hepatic glucose production; bonus wt loss
- SE: lactic acidosis, B12 malabsorption
Don’t use in renal failure
eGFR
What are some sulfonylurea class OHG? How do they work? What are the side effects?
- Gliplizide, gliclazide (good for fat people)
- Increase insulin secretion from pancreatic B cells
- Hypoglycaemia, wt gain
Avoid in elderly or renal failure
- What are examples of thiazolidenidiones?
- How do they work?
- What are the side effects?
- Pioglitazone
- Activates PPAR-gamma -> increases periph gluc uptake
- Fluid retention/CCF, increase bladder CA, Rosiglitazone increases CVD events, pio might be ok
- What are some DPP4 inhibitors?
- How do they work?
- What are the side effects?
- The gliptins: sitagliptin, saxagliptin
- Inhibits DPP4, which breaks down GLP1: Slows gastric emptying, suppress glucagon
- Hypoglycaemia with sulfonylureas, N/V
- Name one GLP-1 mimetic
- How does it work?
- What are the side effects?
- Exenatide
- Slows gastric emptying, suppressed glucagon
- Hypoglycaemia when used with sulfonylureas, N/V
What does dapaglifozin do?
What are the side effects?
Inhibits glucose transport in the kidneys, leading to excretion
Side effects: UTI risk, euglycaemic ketoacidosis (withhold perioperatively or if fasting)
How would you commence insulin therapy?
0.5 units/kg/day
With 40% being long acting
Aim BSL 4 - 7
What are factors that contribute to hypoglycaemic episodes?
- altered diet
- injection errors
- renal disease
- exercise
What is the Somogyi effect and how is it treated?
Rebound hyperglycaemia after nocturnal hypoglycaemia
Mx: reduce note Insulin dose
What is the dawn phenomenon?
Morning hyperglycaemia without nocturnal hypo
Treat: increase Nocte insulin
What are the criteria for micro, macro and nephrotic range proteinuria?
Micro: 30-300mg/day
Macro: >300mg/day
Nephrotic: >3g/day
What are the investigations for diabetic nephropathy?
- Urine ACR
- 24hr urine collection for protein
- EUC
- renal ultrasound: look for small kidneys
- hba1c
How do you manage diabetic nephropathy?
- control BP (Aim 125/75
What are signs of diabetic retinopathy on fundoscopy?
- dot and blot haemorrhages
- hard and soft exudates (soft: cotton wool spots)
- neovascularisatiom
What is the usual order of progression of microvascular complications?
- retinopathy
- nephropathy
- neuropathy
What are the features of diabetic neuropathy?
- sensory neuropathy/parasthesia
- ulcers
- Charcot foot
- autonomic neuropathy: impotence, postural hypotension, delayed gastric emptying, bladder dysfunction
How do you manage diabetic neuropathy?
>Non pharm: - podiatrist, orthotics, footwear >Pharm: - BSL control - analgesia, adjuncts (pregabalin, TCA)
How would you manage autonomic neuropathy in diabetes?
- Postural hypotension: med review, stockings, fludrocortisone
- Impotence: med review, exclude other causes, sildafenil, implant
- Gastroparesis: promotility agents, such as metoclopramide
- Large bowel: (constipation or diarrhea) loperamide, codeine, aperients
- Bladder: self cath, regular toileting
What investigations for osteoporosis?
- BMD (-2.5 or -1.5 on steroids)
- Ca and Vit D
- PTH
- LFT/ALP
- TFT
- EUC
- EPG/IEPG
- testosterone in males
What are the management options for osteoporosis?
=========================
> Non pharm: prevent falls and fracture
Pharm:
- Ca and Vit D replacement
- bisphosphonates
- denosumab (use if CKD)
- raloxifene: SERM - reduces postmenopausal bone loss; decreased risk of breast Ca, higher risk of DVT - use if high risk of breast ca
- teriparatide: synthetic PTH - increases bone formation; side effect of sarcoma risk. (2nd line)
