General (6) Flashcards
Describe the presentation of anaphylaxis.
Sudden-onset following a trigger
Breathlessness
Facial swelling
Hypotension
What is the first step in the management of anaphylaxis?
IM adrenaline
When is IV adrenaline used?
Cardiac arrest (0.5)
What are the three drugs used in the treatment of anaphylaxis? State their relative proportions.
Adrenaline – 1 mg
Chlorpheniramine – 10mg
Hydrocortisone – 100mg
Which antibiotics are used in the treatment of community-acquired pneumonia? Explain why each of them is used.
Amoxicillin – covers the most common cause of CAP (Streptococcus pneumoniae)
Clarithromycin (oral) – a macrolide that covers atypical organisms
Which drug is used to treat hospital-acquired pneumonia and which bacteria does it cover?
Tazocin – covers Gram-negatives
Which drug is used in patients with suspected MRSA?
Vancomycin
List some atypical organisms that can cause pneumonia.
Mycoplasma pneumoniae
Chlamydia pneumoniae
Legionella pneumophilia (40% of CAP)
What would be your first investigation in a patient presenting with dyspepsia and weight loss?
OGD
If no abnormality is detected with this investigation, what would you do next?
Colonoscopy
How would you investigate microcytic anaemia?
Haematinics – iron studies (e.g. ferritin, folate and B12)
Ferritin and Folate is an acute phase protein; raised in Inflamx Infx and Malig.
What must you bear in mind when looking at serum ferritin levels?
Coeliac disease; systemic AI condition bc gluten peptides (wheat, barley, rye); affects 1%.
Which other test would you perform in a patient with GI disturbance and microcytic anaemia?
Tissue transglutamine antibodies (tTG)
Which other test must you do alongside the tTG?
Serum IgA levels (because IgA deficiency can give false-negative tTG results)
How is a diagnosis of coeliac disease confirmed?
Duodenal biopsy – shows subtotal villous atrophy with crypt hyperplasia
What is a common hospital-acquired cause of explosive bloody diarrhoea? What is the major risk factor?
Pseudomembranous colitis (C. difficile colitis) Antibiotic use is the main risk factor
What 2 differentials must you consider in an elderly patient with bloody diarrhoea?
Ischaemic colitis - affects small vessels, as opposed to mesenteric ischaemia
Pseudomembranous colitis
List a differential diagnosis of bloody diarrhoea.
Infective colitis Inflammatory (e.g. IBD) Ischaemic colitis Malignancy Diverticulitis
How would you treat a patient with AF, presenting 4 hours after the onset of symptoms?
DC cardioversion
Which drug can be used to chemically cardiovert pretty much all arrhythmias?
Amiodarone
Describe the direction of blood flow in the veins involved in caput medusa.
Below the umbilicus, the blood within the veins flows towards the legs
What are the two Trousseau’s signs?
Whats the Troisier sign?
Trousseau’s sign of latent tetany – in patients with hypocalcaemia, inflation of a blood pressure cuff around the arm leads to carpopedal spasm
Trousseau’s sign of malignancy – thrombophlebitis occurring as an early sign of gastric or pancreatic cancer
Troisier’s - enlarged L SupraV LN due to 2ndary enlargment
Portal hypertension may present with signs of decompensated liver failure. Give some examples of such signs.
Encephalopathy
Ascites
SBP
Variceal bleed
What is another name for target cells?
Codocytes
NOTE: they have an increased red cell surface membrane
What are target cells a sign of?
Hyposplenism
What is microangiopathic haemolytic anaemia?
Breakdown of red blood cells in small vessels
Describe how DIC causes haemolytic anaemia.
Clots form in narrow vessels; fibrin strands trap RBC, cannot easily pass through so end up haemolysing
It is a process of repeatedly making and breaking clots and is seen in very sick patients (e.g. sepsis)
Why are DIC patients prone to bleeding?
It leads to the consumption of all the clotting factors meaning that clotting is impaired
List the main features of DIC on a blood test.
Low platelets + low fibrinogen
High PT/APTT
High D-dimer/fibrin degradation products (fibrinolysis)
List the main features of HUS on a blood test.
Haemolysis -> low Hb + high bilirubin
Uraemia -> high urea (due to abnormal renal function)
Thrombocytopaenia
(Triggered by Haemolytic E. Coli 0157)
What is TTP?
HUS + fever + neurological manifestations
List some hereditary causes of haemolytic anaemia.
Cell Membrane Defects – hereditary spherocytosis
Enzyme Defects – G6PD deficiency, pyruvate kinase deficiency
Haemoglobinopathies – sickle cell disease, thalassemia
List some acquired causes of haemolytic anaemia.
Drugs Autoimmune haemolytic anaemia SLE Infection (e.g. malaria) MAHA
How can you differentiate small bowel from large bowel on an abdominal X-ray?
Small Bowel - < 3 cm + valvulae conniventes (Kerckring’s folds)
Large Bowel - < 6 cm + haustra
Outline the management of bowel obstruction.
NBM
Drip and suck (IV fluids + aspirate stomach contents using NG tube)
What is the normal range for serum sodium?
135-145 mEq/L
What must you assess first in a hyponatraemic patient?
Volume status
List some features of hypovolaemic patients
Postural hypotension
Dry mucous membranes
Tachycardia
Reduced tissue turgor
This leads to decreased urine Na as kidney’s trying to reabsorb - this is a good sign in hyponatremia
List some features of hypervolaemic patients
Peripheral oedema
Increased JVP
Fluid retention
List the main causes of hyponatraemia associated with hypovolaemia
Diarrhoea Vomiting Diuretics Loss to skin, peritoneal cavity (pancreatitis) i.e. extra-renal fluid loss
List the main causes of hyponatraemia associated with euvolaemia
Adrenal insufficiency (urinary sodium = high)
Hypothyroidism
SIADH
List the main causes of hyponatraemia associated with hypervolaemia
Heart failure
Cirrhosis
Nephrotic syndrome
Which hormone is in excess if you have too much water in your system?
ADH
What can cause high ADH?
Appropriate elevation in response to hypovolaemia
SIADH: increased water absorption, blood volume expansion, natriuretic peptide -> decreased Na+
(Treat SIADH w/ fluid restriction)
Describe the pattern of plasma sodium and urine sodium in SIADH.
Low plasma sodium (osmolality)
High urine sodium (osmolality)
Why might you perform a CXR or Brain MRI in a patient with euvolaemic hyponatraemia?
CXR – look for lung pathology that might be a source of ectopic ADH
Brian MRI – look for CNS pathology that might be a source of ectopic ADH
Describe the urine sodium levels in a patient with hypovolaemic hyponatraemia.
Low urine sodium – the kidneys are trying to retain as much water and salt as possible
What might make the interpretation of urine sodium difficult?
Use of diuretics
Which investigations might you perform in a patient with euvolaemic hyponatraemia?
TFTs
Short synacthen test
Check plasma and urine sodium
Describe the urine sodium levels in a patient with hypervolaemic hyponatraemia. Explain why this is the case.
Low urine sodium – this is because the conditions that cause hypervolaemic hyponatraemia lead to increased aldosterone secretion (which increases sodium reabsorption in the kidneys)
Almost all causes of hyponatraemia are associated with high ADH. List two rare causes.
Excessive water intake
Sodium-free irrigation solutions (e.g. used in TURP)
List some causes of SIADH.
CNS pathology (e.g. stroke, tumour, abscess)
Lung pathology (e.g. pneumonia, PE, lung cancer)
Drugs
Tumours (Ectopic ADH)
List some drugs that can cause SIADH.
SSRIs TCAs Opiates PPIs Carbamazepine
What can happen if you correct hyponatraemia too rapidly?
Cerebral oedema -> central pontine myelinolysis
What is the maximum rate at which you should correct hyponatraemia?
8 mmol/24 hrs
Outline the treatment of:
hypovolaemic hyponatraemia
IV fluids
Outline the treatment of euvolaemic hyponatraemia
What is dangerous to give?
Fluid restriction
NOTE: normal saline may be dangerous in these patients because it increases plasma sodium leading to more fluid retention
Under what conditions do you give hypertonic saline to patients with euvolaemic hyponatraemia?
If the patient is fitting or has a low GCS
What is onycholysis?
Separation of the nail from the nail bed
List 4 causes of onycholysis.
Trauma
Thyrotoxicosis
Psoriasis
Fungal infection
What are beau’s lines and what are they caused by?
Alternating dark and white lines in the nail
Occur in patients with recurrent episodes of illness of chemotherapy (due to arrest of growth, then growth, then arrest of growth etc.)
What is koilonychias and what is it caused by?
Spooning of the nail
Caused by severe iron deficiency anaemia
What is nail pitting a sign of?
Psoriasis
What is leukonychia a sign of?
Hypoalbuminaemia, liver disease
Which blood results must you be aware of to diagnose DKA?
High capillary/blood glucose
Acidosis
Capillary ketones
List the complications of diabetes mellitus:
Microvascular
- Retinopathy
- Nephropathy
- Neuropathy
Macrovascular
- Ischaemic heart disease
- Cerebrovascular disease
- Peripheralvascular disease
Metabolic
- DKA
- Hyperosmolar hyperglycaemic state (HHS)
- Hypoglycaemia
Describe the main ECG change seen in pericarditis.
Widespread saddle-shaped ST elevation
Describe the ECG change seen in left ventricular hypertrophy.
Deep S wave in V1
Tall R wave in V6
The total of the two will be > 7 large squares
If renal colic is suspected, which form of imaging should you request? What does it show?
Non-contrast CT-KUB - can show:
- Pelvi-ureteric junction obstruction
- Calculus within dilated renal pelvis
If you’re in clinic and a patient presented with symptoms of hyperparathyroidism and you want to check whether they have kidney stones, which imaging modality would you use?
Abdominal ultrasound
List some possible causes of high calcium and low PTH.
Malignancy Sarcoidosis Multiple myeloma TB, lymphoma (?PTHrp is driving the Ca)
Which diseases can cause hypercalcaemia and back pain?
Bone metastases Multiple myeloma (normal ALP)
What are the two main sources of ALP?
Bone
Liver
Which type of liver disease causes a rise in ALP?
Obstructive liver disease (also causes a rise in GGT)
List three bone diseases that are associated with a rise in ALP.
Fractures
Malignancy
Paget’s disease
Which bone cells produce ALP?
Osteoblasts
Which condition that causes bone pain is associated with normal ALP?
Multiple myeloma
What defines multiple myeloma and what are the 4 main features?
Differentiated plasma cells, infiltration of BM, presence of monoclonal Ig or Ig fragment in serum +/or urine
M-protein i nserum >30g/L or BM clonal plasma cells >10%
1 or more of following: Calcium (high) Renal impairment Anaemia Bone pain
Which type of benign breast lump is common in young women?
Fibroadenoma – smooth and mobile
Which cause of breast lump is exclusive to lactating women?
Galactocoele
Retention cyst conaining milk located in mammary gland
Also common in preg, post partum
What do most patients with fat necrosis causing a breast lump have a history of?
Trauma to the breast
List some causes of cavitating lung lesions.
Infection – TB, Staphylococcus aureus, Klebsiella (e.g. alcoholics)
Inflammation – rheumatoid arthritis, granulomatosis with polyangiitis (Wegener’s granulomatosis)
Infarction – PE (bland and septic)
Malignancy (SqCC - bronchogenic)
What three things must you consider in patients with peripheral oedema?
Does the patient have heart failure?
Is the patient losing albumin in their bowels?
Is the patient losing albumin in their urine?
Which test can be performed to check for loss of protein in the urine?
Urinalysis
Then 24hr urinary protein
What is nephrotic syndrome caused by?
An increase in the permeability of the glomerular basement membrane to protein
What triad defines nephrotic syndrome?
Proteinuria > 3.5 g/day
Hypoalbuminaemia
Oedema
What are people with nephrotic syndrome susceptible to and why?
Increased risk of thromboembolic disease (due to loss of natural anticoagulants in the urine along with protein)
Patients may present with renal vein thrombosis
What is hereditary haemorrhagic telangiectasia and what might these patients present with?
Autosomal dominant condition in which abnormal blood vessels form in the skin, mucous membranes, lungs, liver and brain, AV malformations
The abnormal vessels are prone to bleeding
SYMPTOMS: recurrent nose and GI bleeds, haemoptysis
What is Peutz-Jegher’s syndrome?
Autosomal dominant condition characterised by the development of benign hamartomatous polyps in the GI tract and hyperpigmented macules on the lips and oral mucosa
If a short synacthen test fails to cause a significant rise in cortisol, what is the diagnosis?
Adrenal insufficiency
What are the two main pathological reasons for a patient might have a high prolactin?
Prolactinoma
Compression of the pituitary stalk (e.g. by a pituitary tumour) leading to a disruption of the flow of dopamine (which exerts an inhibitory effect over prolactin release) – disconnection hyperprolactinaemia
What diagnostic test is done for acromegaly?
Oral glucose tolerance test (OGTT)
Failure of suppression of GH by the administration of glucose suggests acromegaly
NOTE: another test involves the measurement of IGF-1, which will be high in acromegaly
What is the diagnosis in a patient with high FSH/LH but low oestrogen?
Premature ovarian insufficiency (radiotherapy, chemotherapy, AI)
Why does primary hypothyroidism lead to a mild hyperprolactinaemia?
Hypothyroidism leads to an increased production of TRH by the hypothalamus
TRH has a stimulatory effect on prolactin release by the anterior pituitary
What is the most common cause of hyperprolactinaemia?
Pregnancy
Symptoms of pyelonephritis
Fevers, Rigors, Pain when tapping renal angle, increased CRP
How does TB, sarcoidosis and lymphoma change calcium studies?
The granulomas (macrophages) an hydroxylate vitamin D --> activation Increased Ca; decreased PTH
How to diagnose MM?
Serum/urine electrophoresis
- Paraprotein spike IgG >35g/L or IgA >20g/L and light chain urinary excretion >1g/day
Skeletal survey - osteopenia, osteolytic lesions, pathological fracture.
BM aspirate and biopsy - plasma cell infiltration >10% to DDx from MGUS and solitary plasmacytoma
Rarer causes of cavitaing lesions
Trauma (pneumoceles in infancy) - intrapulmonary airfilled cystic spaces.
Youth - CPAM, pulmonary sequestration, bronchogenic cyst
What does systemic sclerosis give you?
Microstomia
Tight Skin
How do you treat HHS
Fluids, K+, insulin
How do you treat hypoglycaemia?
Confused but cooperative: buccal dextrose gel
V confused: IV 10%/20% glucose or IM glucagon
Why is the ALP in MM normal?
Plasma cells produce paraprotein monoclonal Ig and suppress osteoblasts, which usually produces ALP
