Endo 1 Flashcards
What is Diabetes Insipidus?
Inadequate secretion or insensitivity to ADH, leading to ‘Hypotonic Polyuria’
What are the two types of Diabetes Insipidus?
Cranial/Central: Failure of the posterior pituitary to secrete ADH
Nephrogenic: Collecting ducts become insensitive to ADH
What causes Cranial/Central Diabetes Insipidus?
Pituitary Tumour
Infection (Meningitis)
Sarcoidosis
What can cause Nephrogenic DIabetes Insipidus
Hypercalcaemia
Hypokalaemia
Lithium
Inherited Genes (AVPV2)
Idiopathic
How would a patient with Diabetes Insipidus typicall present?
Polyuria (incl. nocturia)
Polydipsia
Symptoms of Hypernatraemia (Lethargy, Irritability, Confusion)
How would you investigate a potential case of Diabetes Insipidus?
U&Es, Glucose
Water Deprivation Test
How is a water deprivation test used to diagnose Diabetes Insipidus?
Water restricted for 8 hours, with plasma and urine osmolality measured every hour.
Give Desmopressin after 8 hours and measure urine osmolality.
In cranial DI - Increase of >50% post-desmopressin
In nephrogenic DI - Increase of <45% post-desmopressin
How do you manage a patient with Diabetes Insipidus?
Treat the underlying cause
Intranasal Desmopressin (Cranial)
Thiazide Diuretics/NSAIDS (Nephrogenic)
How do T1DM and T2DM differ in terms of presentations?
Both present with Polyuria + Polydipsia
T1 presents with Tiredness, weight loss, DKA,
How does a patient experiencing a DKA present?
Nausea and Vomiting
Abdominal Pain
Kussmaul Breathing
Sweet Breath
What are the risk factors for T1 and T2 DM?
T1 - HLA DR3/4, Other autoimmune conditions
T2 - Obesity, FHx, ethnicity, endocrine disease, drug use.
How is Diabetes Mellitus diagnosed?
Fasting Glucose >7 mmol/L
Random Glucose >11.1 mmol/L
How is T1DM managed?
Insulin
Education
Fluids for DKA
How is T2DM managed?
Diet and Lifestyle advice
Metformin +/- sulphonylurea +/- Insulin
What are the main causes of Hyponatraemia?
Hypovolaemic - Diarrhea, Vomiting, Diuretics
Euvolaemic - Hypothyroidism, Hypoadrenalism, SIADH
Hypervolaemia - HF, Cirrhosis, Nephrotic Syndrome
How would you investigate a euvolaemic patient with Hyponatraemia?
TFTs
Short synACTHen test
Drug Review
Breast Exam
CXR/Brain MRI (For tumour - SIADH)
How would you determine the volaemic status of a patient with hyponatraemia?
Hypo - Reduced turgor, postural hypotension, dry mucous membranes
Hyper - Oedematous, High JVP
How does Hypernatraemia present?
Lethargy, irritability, thirst, dehydration, confusion, coma, fits.
What may cause Hypernatraemia?
Rare
Vomiting
Diarrhoea
DI
Primary Aldosteronism
What is SIADH?
Syndrome of Innappropriate ADH secretion.
Not a diagnosis
Need to find an underlying cause.
What can cause SIADH?
CNS Pathology
Lung Pathology
Drugs: SSRI, TCA, Opiates, PPIs, Carbamazepine
Tumours (don’t forget breast)
What can cause Hyperprolactinaemia?
Pituitary Prolactinoma
Hypothyoridism
Drugs (Metoclopramide, antipsychotics)
Physiological causes, such as pregnancy
How does hyperprolactinaemia present?
Women - Galactorrhoea, amenorrhoea, infertility
Men - Loss of libido, infertility, galactorrhoea
Tumour Symptoms - Headache, Bitemporal Hemianopia
How would you investigate the cause of Hyperprolactinaemia?
Prolactin levels
TFTs
Pituitary MRI
How would you manage a patient with Hyperprolactinaemia?
1) DA Agonist - Bromocriptine (Amir Sam says Cabergoline - both are used)
2) Surgery
How does Hyperthyroidism present?
Heat Intolerance, Sweating
Palpitations
irritable
Weight Loss (Good appetite)
Diarrhoea
Menstrual Irregularities/Impotence
Tremor
How does Hypothyroidism present?
Cold Intolerance
Bradycardia
Lethargy
Weight Gain
Constipation
Menstrual Disturbance
Dry skin
What are the main causes of Hyperthyroidism?
Grave’s Disease
De Quervain (Viral) thyroiditis
Toxic Multinodular Goitre
Adenoma
What is Grave’s Disease?
Autoantibodies to TSH receptor
Associated with other Autoimmune Diseases
Triad = Exopthalmos, Pretibial Myxoedema, Thyroid Acropachy (Nail changes)
How does De Quervain’s Thyroiditis typically present?
Post-Viral
Presents with Fever, high ESR, Painful Goitre
Self-Limiting (NSAID treatment)
How does Toxic Multinodular Goitre typically present?
In the elderly, and in areas where iodine diet deficincies are more likely.
What is a Thyroid Adenoma?
Single nodule producing T3/4
What would you see on Radioisotope Uptake scans for the main common causes of Hyperthyroidism?
Grave’s - Diffuse increased uptake
De Quervain’s Thyroiditis - No Uptake
TMG - Multiple areas of increased uptake
Adenoma - Single area of increased uptake
What are the main causes of Hypothyroidism?
Autoimmune Hashimoto’s Thyroiditis (Common in the West)
Iodine Deficiency (Common Worldwide)
Iatrogenic - Post-Surgery, radioiodine, amiodarone
De Quervain’s Thyroiditis - Hypo once supplies are exhausted
Congenital
How would you manage a patient with Hypothyroidism?
Levothyroxine
What are the main types of Thyroid Cancer?
Papillary
Follicular
Medullary
Lymphoma
Anaplastic
What is Papillary Thyroid Cancer?
Most Common, affecting younger patients
Risk factor- Radiation Exposure
SBA Buzzwords - ‘Psammoma Bodies’, ‘Orphan Anne Nuclei’
What is Follicular Thyroid Cancer?
Type affecting middle aged women predominantly
SBA Buzzwords - Hurthle Cells
What is Medullary Thyroid Cancer associated with?
MEN2, FHx important
What is a Thyroid Lymphoma?
Cancer more common in females, general occurs after ore-existing Hashimoto’s thyroiditis
What is Anaplastic Thyroid Cancer?
The most aggressive Thyroid Cancer
Affects mainly Elderly Females
SBA Buzzwords - Giant Cells, Pleomorphic Hyperchromatic Nuclei
What is Acromegaly?
Hypersecretion of GH in Adults.
What most commonly causes Acromegaly?
GH secreting Adenoma in the Pituitary
How does Acromegaly typically present?
Rings and shoes become tight
Sweaty, oily skin
Weight Gain
Headaches/Vision changes
Carpal Tunnel Syndrome
HTN
Insulin Resistance
How would you investigate a possible case of Acromegaly?
Serum IGF-1 as screening
OGTT - Failure to suppress GH after being given glucose orally - this is diagnostic.
MRI brain to assess tumour
How do you manage Acromegaly?
1) Transphenoidal Hypophysectomy
2) Somatostatin Analogue (Octeotride)
What is Multiple Endocrine Neoplasia?
Autosomal dominant condition causing the formation of multiple hormone-producing tumours in mutliple organs.
What is MEN1?
The formation of Endocrine tumours in the Parathyroid Gland, Pancreas and Pituitary Gland
What can a MEN1 tumour in the Pituitary cause?
Hyperprolactinaemia
Acromegaly
Hyperadrenalism
Carcinoid Syndrome
Which tumours does MEN2 typically present with?
Thyroid (Medullary)
Adrenal (Phaeochromocytoma)
Parathyroid Hyperplasia
What is Carcinoid Syndrome?
Syndrome caused by systemic release of humoural factors from Carcinoid Tumours
Leads to increased production of secretory products, such as Serotonin, Histamine, Tachykinins and prostaglandins.
Commonly occur in the Appendix and Rectum
How does Carcinoid Syndrome typically present?
Paroxysmal Flushing
Diarrhoea
Crampy Abdo pain
Wheeze
Sweating
Palpitations
How would you investigate a possible case of Carcinoid Syndrome?
24Hr Urinary 5-HIAA Levels
Serotonin metabolite, increased in Carcinoid Syndrome
CT/MRI to localise tumours
