Data interpretation

Question 1

Q3.1

Answer 1

Stop
- clozapine - agranulocytosis
- propanolol and ibuprofen - CI in asthmatics

Question 2

Causes of microcytic anaemia
1. Most common
2. TAILS

Answer 2

Most common - IDA

T – Thalassaemia
A – Anaemia of chronic disease
I – Iron deficiency anaemia
L – Lead poisoning
S – Sideroblastic anaemia

Question 3

Causes of normocytic anaemia
1. Most common
2. 3A2H

Answer 3

Most common: anaemia of chronic disease and acute blood loss

A – Acute blood loss
A – Anaemia of Chronic Disease
A – Aplastic Anaemia
H – Haemolytic Anaemia
H – Hypothyroidism

Question 4

Macrocytic anaemia
1. Most common
2. Megaloblastic
3. Normoblastic

Answer 4

1. B12 deficiency/ folate deficiency
   Excess alcohol
   Liver disease (non-alcoholic causes included)
2. B12 deficiency/ folate deficiency
3. Alcohol
   Reticulocytosis (usually from haemolytic anaemia or blood loss)
   Hypothyroidism
   Liver disease
   Drugs such as azathioprine

Question 5

Neutrophilia causes

Answer 5

MC: Bacterial infection
- tissue damage
- steroids

Question 6

Neutropenia

Answer 6

MC: Viral infection, clozapine, carbimazole

• chemo/radiotherapy

Question 7

Lymphocytosis

Answer 7

MC: Viral infection

• Lymphoma
• Chronic lymphocytic leukemia

Question 8

Neutropenic sepsis

Answer 8

Patient on anti-cancer or immunosuppressant treatment gets neutropenia <1

Question 9

Thrombocytopenia

Answer 9

M/C: Drugs e.g. penicillamine and heparin

• Reduced production: infection, drugs e.g. penicillamine, myelodysplasia, myelofibrosis, myeloma
• Reduced destruction: heparin, hypersplenism, DIC, ITP, haemolytic uremic syndrome

Question 10

Hyponatraemia
1. Hypovolaemic
2. Euvolaemic
3. Hypervolaemic

Answer 10

1. M/C: fluid loss (esp. diarrhoea and vomiting) + diuretics (any type)
   - Addison’s
2. SIADH, psychogenic polydipsia, hypothyroidism
3. M/C: HF, renal failure
   - liver failure, nutritional failure (both causing hypoalbuminaemia)
   - Thyroid failure (hypothyroidism, can be euvolaemic too)

Question 11

Causes of SIADH

Answer 11

S mall cell lung tumours
I nfection
A bscess,
D rugs (especially carbamazepine and antipsychotics)
H ead injury

Question 12

Causes of hypernatraemia (4Ds)

Answer 12

Dehydration
Drips (too much saline)
Drugs
Diabetes insipidus

Question 13

Hypokalaemia (DIRE)

Answer 13

M/C: Drugs (loop and thiazide diuretics)

Inadequate intake or intestinal loss (e.g. vomiting/diarrhoea)
Renal tubular acidosis
Endocrine (Cushing’s and Conn’s)

Question 14

Hyperkalaemia (DREAD)

Answer 14

M/C: Drugs (K+ sparing diuretics and ACE-i)

Renal failure
Endocrine (Addison’s disease)
Artefact (v common, due to clotted sample
DKA

Question 15

What can a raised urea be a sign of?

Answer 15

AKI and upper GI bleed

Question 16

Why is urea raised in upper GI bleed

Answer 16

Urea is a breakdown product
of amino acids (such as globin chains in haemoglobin) (blood broken down by gastric juice and urea absorbed)

Question 16

1. What to do if raised urea but normal creatinine in a patient who is not dehydrated (i.e. does not have prerenal failure)

Answer 16

Check Hb –> if low, possible GI bleed

Question 17

Types of AKI

Answer 17

1. Pre-renal (70%)
2. Intrinsic (10%)
3. Post-renal (i.e. obstructive, 20%)

Question 18

Pre-renal AKI (70%)
1. Biochemical disturbance
2. Causes

Answer 18

1. Urea rise&raquo_space; creatinine rise
2. • Dehydration (or if severe, shock) of any cause, e.g. sepsis, blood loss.
     - Renal artery stenosis (RAS)∗

Question 19

Intrinsic AKI (10%)
1. Biochemical disturbance
2. Causes (INTRINSIC)

Answer 19

1. Urea rise «creatinine rise, bladder or hydronephrosis not palpable
2. M/C: N + T

I schaemia (due to prerenal AKI, causing acute tubular necrosis)
N ephrotoxic antibiotics ∗∗
T ablets (ACEI, NSAIDs)
R adiological contrast
I njury (rhabdomyolysis)
N egatively birefringent crystals (gout)
S yndromes (glomerulonephridites)
I nflammation (vasculitis)
C holesterol emboli

Question 20

Post-renal AKI (20%)
1. Biochemical disturbance
2. Causes (lumen, wall, external pressure)

Answer 20

1. Urea rise «creatinine rise, bladder or hydronephrosis may be palpable
2. In lumen: stone or sloughed papilla

In wall: tumour (renal cell, transitional cell), fibrosis

External pressure: benign prostatic hyperplasia, prostate cancer, lymphadenopathy, aneurysm

Question 21

Note regarding differentiating severe pre-renal AKI with high creatinine and intrinsic/obstructive AKI

Answer 21

multiply the urea by 10; if it exceeds the creatinine (showing a relatively greater increase in urea compared to creatinine) then this suggests a pre-renal aetiology.

Question 22

Nephrotoxic antibiotics

Answer 22

Gentamicin, vancomycin and tetracyclines

Question 23

How is AKI usually triggered in renal artery stenosis

Answer 23

ACE-i or NSAIDs

Question 24

Liver function: markers of hepatocyte injury or cholestasis

Answer 24

- bilirubin - alanine aminotransferase (ALT) and the less commonly measured aspartate aminotransferase (AST) - alkaline phosphatase (alk phos or ALP).

Question 25

Liver function: synthesis markers

Answer 25

- albumin - vitamin K-dependent clotting factors (II, VII, IX and X) measured via prothrombin time (PT)/international normalized ratio (INR).

Question 26

What would a raised bilirubin on its own indicate?

Answer 26

A raised bilirubin on its own indicates prehepatic jaundice (Same as single raised urea indicates pre-renal injury) bilirubin is a breakdown product of haemoglobin, think haemolysis

Question 27

Common causes of a raised Alk Phos (ALKPHOS)

Answer 27

Any fracture Liver damage (posthepatic) K (for kancer) Paget’s disease of bone and Pregnancy Hyperparathyroidism, Osteomalacia, and Surgery.

Question 28

Deranged LFTs: pre-hepatic 1. Biochem 2. Causes

Answer 28

1. Single raised bilirubin 2. M/C: Haemolysis - Gilbert's and Crigler-Najjar syndromes

Question 29

Deranged LFTs: intra-hepatic 1. Biochem 2. Causes

Answer 29

1. Raised bilirubin AND raised AST/ALT 2. M/C: hepatitis, cirrhosis, malignancy - Fatty liver - Metabolic (Wilson's disease/haemochromatosis) - HF (causing hepatic congestion)

Question 30

Deranged LFTs: post-hepatic (obstructive) 1. Biochem 2. Causes (in lumen, in wall, ext pressure)

Answer 30

1. Raised bilirubin AND raised ALP 2.M/C: Gallstones, drugs causing cholestasis, gastric/pancreatic cancer In lumen: gallstones, drugs causing cholestasis In wall: tumour (cholangiocarcinoma), PBC, sclerosing cholangitis Ext pressure: pancreatic or gastric cancer, lymph node

Question 31

Common causes of hepatitis and cirrhosis

Answer 31

(1) alcohol (2) viruses (Hepatitis A–E, CMV, and EBV) (3) drugs (paracetamol overdose, statins, rifampicin) (4) autoimmune (primary biliary cirrhosis, primary sclerosing cholangitis, and autoimmune hepatitis).

Question 32

Drugs causing cholestasis

Answer 32

Flucloxacillin CO-AMOXICLAV nitrofurantoin steroids sulphonylureas

Question 33

TFTs: Low T4, high TSH 1. Type of hypothyroidism 2. Cause

Answer 33

1. Primary hypothyroidism (low T4 causes high TSH) 2. Hashimoto's thyroiditis, drug-induced hypothyroidism

Question 34

TFTs: Low T4, low TSH 1. Type of hypothyroidism 2. Cause

Answer 34

1. Secondary hypothyroidism (low TSH from pituitary causes low T4) 2. Pituitary tumour or damage

Question 35

TFTs: High T4, low TSH 1. Type of hypothyroidism 2. Cause

Answer 35

1. Primary hyperthyroidism (high T4 causes low TSH) 2. Grave's disease, toxic nodular goitre, drug-induced

Question 36

TFTs: high T4, high TSH 1. Type of hypothyroidism 2. Cause

Answer 36

1. Secondary hyperparathyroidism (high TSH from pituitary causes high T4) 2. Pituitary tumour

Question 37

How to interpret and change levothyroxine dose following TFT results (TSH range mIU/L)

Answer 37

<0.5 Decrease dose 0.5–5 Nil action – same dose >5 Increase dose

Question 38

Digoxin toxicity

Answer 38

Confusion, nausea, visual halos, and arrhythmias

Question 39

Lithium toxicity

Answer 39

Early: tremor Intermediate: tiredness Late: arrhythmias, seizures, coma, renal failure, and diabetes insipidus

Question 40

Phenytoin toxicity

Answer 40

Gum hypertrophy, ataxia, nystagmus, peripheral neuropathy, and teratogenicity

Question 41

Gentamicin/vancomycin toxicity

Answer 41

Ototoxicity and nephrotoxicity

Question 42

Paracetamol metabolism and overdose

Answer 42

Metabolised by glutathione In excess, glutathione is depleted and NAPQI builds up (toxic) --> acute liver damage

Question 43

Which are the vitamin K-dependent clotting factors

Answer 43

II, VII, IX, and X

Question 44

Warfarinised patients: what to do in major bleed

Answer 44

- stop warfarin * give 5–10 mg IV phytomenadione (vitamin K) - give prothrombin complex (e.g. Beriplex®) https://bnf.nice.org.uk/treatment-summaries/oral-anticoagulants/#vitamin-k-antagonists

Question 45

Drugs that cause hyponatraemia

Answer 45

Carbamazepine, diuretics, SSRIs (esp citalopram), Antipsychotics (esp