15/12/2015 Interactive Cases in General Medicine 5 Flashcards
40M with fever, rigour, tachycardia, hypotension, chest pain, dark urine. Post-op, what is the diagnosis?
Immediate transfusion reaction, haemolysis
What are the causes of polycythaemia?
If primary: myeloproliferative
If secondary: high altitude, chronic hypoxia (COPD), EPO from iatrogenic/artificial sources or renal cell carcinoma
Low platelets, thrombocytopenia causes?
Increased use: DIC, ITP
Decreased production: infiltration
Increased pooling in the spleen: chronic liver disease
50M with rheumatoid arthritis, normal/high ferritin, normocytic anaemia. What must still be investigated?
Ferritin is an acute phase reactant which increases in chronic disease (hence normocytic), it is artificially normal and will mask a GI/UG bleed
40F, Hb 110, MCV 65 what is the diagnosis?
Beta thalassaemia heterozygosity, the MCV is disproportionately low in comparison to the Hb
Causes of a macrocytic anaemia?
“Alcoholics May Have Liver Failure”
- Alcohol (raised GGT)
- Myelodysplasia (pancytopaenia, low cell lines)
- Hypothyroidism (history, T4, TSH)
- Liver disease
- Folate/B12 deficiency (small bowel disease, gastrectomy, Schilling Test)
Presentation of polycythaemia?
Headache, blurred vision (hyper viscosity), tinnitus, pruritus after a hot bath, stroke/DVT, gangrene, choreiform movements
How is an acute painful crisis of sickle cell anaemia managed?
Analgesia, O2, IV fluids, Abx
How is a stroke from SCA managed?
Exchange blood transfusion
How is sequestration managed?
RBC pooling in lungs causes cough, fever, SOB. In spleen causes exacerbation of anaemia; treat with splenectomy and Abx
How are gallstones managed?
Cholecystectomy
What are the complications of sickle cell anaemia?
Painful crises, splenic/lung sequestration, gallstones/cholecystitis, stroke
Presenting features of multiple myeloma?
CRAB
- Hypercalcaemia (polyuria, polydipsia, constipation due to nephrogenic DI, insensitive to ADH)
- Renal failure (Ur+Cr)
- Anaemia
- Bone pain, osteoporosis (DXA)
- Infection due to immunoparesis from clonal expansion of one Ig
- Cord compression due to spinal involvement
What is the pathophysiology of MM? How is it investigated and confirmed?
Clonal proliferation of immunoglobulin paraprotein. Confirm with urine Bence-Jones proteins (light chain Ig) or serum electrophoresis showing Ig
What is the differential diagnosis for a 50M with high calcium, low PTH?
Malignancy, myeloma, sarcoidosis
- HIGH ALP = malignancy or sarcoidosis
- LOW/NORMAL ALP = myeloma. Plasma cells suppress osteoblasts, hence ALP is unchanged
What is the differential diagnosis for a 50M with high calcium, high PTH?
Primary hyperparathyroidism
FHH familial hypocalciuric hypercalcaemia
Causes of anaemia with reticulocytosis
Haemolytic crisis: haemorrhage
Causes of anaemia with low reticulocytes
Marrow problem: parvovirus B19 infection, SCA aplastic crisis, blood transfusion
How is diabetes diagnosed?
Fasting >7, random >11.1 (retinopathy increases beyond these figures)
What is impaired fasting glucose/impaired glucose tolerance?
IFG 6-7
IGT 7.8-11.1 after OGTT; 75g glucose 2h
Which antibodies may be present in T1DM?
Anti-islet cell Ab
Anti-GAD Ab
Metformin and sulphonylurea (weight loss/neutral/gain?)
Metfomin weight neutral (and reduced mortality), sulphonylurea weight gain
Diabetic drugs
Metformin - biguanide
Sulphonylureas include gliclazide, glibenclamide. Weight gain
Pioglitazone - thiazolidinediones, not for heart failure (rosiglitazone), weight gain
Insulin - weight gain
Sitagliptin - DPP4 inhibitor, weight neutral
GLP-1 agonist - exenatide, incretin mimetic lower risk of hypos, weight loss
SGLT2 inhibitors - glifozin, weight loss, inhibit resorption of glucose from the kidney
Acarbose - alpha glucosidase inhibitor
How is diabetic nephropathy screened for?
ACR albumin-creatinine ratio. Want to detect microscopic albuminuria before urine dipstick and prevent progression of renal disease
How is DKA/HHS treated?
IV fluids, potassium, insulin
What is sliding scale insulin?
A variable rate IV insulin infusion, if glucose X, give dose Y. in T1DM, never give 0. Given as actrapid + saline, if patient is unwell, sepsis, surgery, not eating
Graves signs and symptoms
Tremor, tachycardia, palpitations, weight loss good appetite, irregular periods, proptosis, pretibial myxoedema, cheimosis, smooth goitre,
Investigations for Graves
TFT high T3/4, low TSH, TSH-R AutoAb high
Tc-99m uptake scan high diffuse uptake, as TSH-like Ab is present
Thyroid cancer presentation
Lump in the neck, family history, radiotherapy/radiation exposure, rapid enlargement and compression, lymphadenopathy
Types of thyroid cancer
Follicular, papillary, medullary, anaplastic
Investigations thyroid cancer
USS malignant features, Tc-99m scan cold nodules, no uptake. FNAC, MDT
Treatment thyroid cancer
Surgery, thyroxine replacement, radio iodine ablation
Bitemporal hemianopia, expressing milk, low sex drive, no periods
Prolactinoma: galactorrhea, amenorrhoea, low libido. Men present later with bitemporal hemianopia. Give cabergoline to shrink the tumour and lower PRL. Transphenoidal surgery is possible
Cushing syndrome symptoms
Thin skin/easy bruising, proximal myopathy, purple striae. HTN, DM, osteoporosis at a young age
Tired, depressed, hairy, weight gain central obesity
Causes of amenorrhoea/oligomenorrhoea?
Pregnancy - b-HCG
Hypothalamus - low BMI, excess exercise
Pituitary - prolactinoma high PRL, low FSH/LH suppressed
Thyroid - high or low
Ovarian failure - high FSH, low oestrogen
PCOS - hirsute, high androgens
How does hypokalaemia present?
Arrhythmia, weakness, polyuria (similar to hyperCa, nephrogenic DI develops)
What are the causes of hypokalaemia?
Vomiting, diuretics, primary hyperaldosteronism (bilateral hyperplasia or Conn’s) this is investigated with aldosterone:renin ratio, renin is low due to negative feedback
A young man on 3 antihypertensives (and still uncontrolled) presents with HTN, low K, high aldosterone. What is the diagnosis and how is he investigated?
Aldosterone:renin ratio is high due to Conn’s syndrome, primary hyperaldosteronism: Na retention, K excretion. 1 sided tumour remove, give spironolactone if bilateral
How do you assess for euvolaemic causes of hyponatraemia?
SIADH, hypothyroid, hypo adrenal: urine/plasma osmolality, TFT, short synACTHen test
What is the urine sodium in hyper/hypovolaemic hyponatraemia?
LOW in both due to low renal perfusion, renin increase, aldosterone increase, more water and salt resorption
How is osmolality calculated?
2(Na+K)+U+glucose
Causes of high urine osmolality?
Dehydration, HHS, T2DM
Causes of low urine osmolality?
Diabetes insipidus –> dilute urine
1 Low Ca, high PTH, low phosphate
Vitamin D deficiency, secondary hyperparathyroidism due to low Ca
2 High Ca, low phosphate, high PTH
Primary hyperparathyroidism (phosphate trashing hormone)
3 Low Ca, high phosphate, low PTH
Primary hypoparathyroidism
4 High Ca, low PTH, normal phosphate
Malignancy, myeloma, sarcoidosis (check ALP, if high, then malignancy. Serum ACE for sarcoid)
5 High phosphate, low Ca, high PTH
Renal failure, secondary hyperparathyroidism. High phosphate due to renal failure, low Ca due to kidney failure inability to hydroxylate vitamin D
Pearly lesion on skin
BCC
Oligoarthritis, sacroilitis, DIP arthritis, nail changes
Psoriatic arthritis
Why is there tingling of fingers in hyperventilation?
Respiratory alkalosis causes albumin to bind Ca, transient low Ca causes tingling sensation. Chvostek and Trousseau sign
Renal artery stenosis Ix
Small kidney = stenosis, asymmetrical. Investigate with MR angiography, if bilateral, do NOT give ACEi causes renal failure. Cause of pre-renal AKI
