Data interpretation

Question 1

Causes of neutrophilia

Answer 1

Bacterial infection
Tissue damage (inflammation / infarct / malignancy)
Steroids

Question 2

Causes of neutropenia

Answer 2

Viral infection
CTX or RTX
Clozapine (antipsychotic)
Carbimazole (antithyroid)

Question 3

Causes of lymphocytosis

Answer 3

Viral infection
Lymphoma
CLL

Question 4

Causes of low platelets (2 categories)

Answer 4

Reduced production: infection (viral), drugs (penacillamine), myeloproliferative disorders
Increased destruction: heparin, hypersplenism, DIC, ITP, HUS/TTP

Question 5

Causes of high platelets (2 categories)

Answer 5

Reactive: bleeding, tissue damage (infection/inflammation/malignancy), post-splenectomy
Primary: myeloproliferative disorders

Question 6

Causes of hypernatraemia (begin with ‘d’)

Answer 6

Dehydration, drips (IV fluids), drugs (effervescent / high Na+ content), diabetes insipidus.

Question 7

Causes of hyponatraemia (3 categories)

Answer 7

Hypovolaemic: fluid loss (d/v), Addison’s disease, diuretics
Euvolaemic: SIADH, psychogenic polydipsia, hypothyroidism
Hypervolaemia: Heart failure, renal failure, hypoalbuminaemia (liver failure / nutritional failure), hypothyroidism

Question 8

Causes of SIADH

Answer 8

Small cell lung tumour
Infection (atypical pneumonia)
Abscess (cerebral)
Drugs (carbamazepine, amitriptyline, SSRIs)
Head injury (meningitis, SAH)

Question 9

Causes of hypokalaemia (pneumonic)

Answer 9

DIRE:
Drugs (loop and thiazide diuretics)
Inadequate intake or Intestinal loss (d/v)
Renal tubular acidosis
Endocrine (Cushing’s and Conn’s syndrome)

Question 10

Electrolyte abnormalities in Addison’s disease

Answer 10

Hyponatraemia and hyperkalaemia

Question 11

Electrolyte abnormalities in Cushing’s syndrome

Answer 11

Hypernatraemia and hypokalaemia

Question 12

Electrolyte abnormalities in Conn’s syndrome

Answer 12

Hypernatraemia and hypokalaemia

Question 13

Causes of hyperkalaemia (pneumonic)

Answer 13

DREAD:
Drugs (ACEi & K-sparing diuretics)
Renal failure
Endocrine (Addison's)
Artefact (very common, due to clotted sample)
DKA

Question 14

Biochemical disturbance in pre-renal AKI

Answer 14

Urea rise&raquo_space; creatinine rise

E.g. urea 19 (3-7.5 mmol/L) creatinine 110 (35-125 umol/L)

Question 15

Causes of pre-renal AKI

Answer 15

Dehydration or severe shock of any cause e.g. blood loss or sepsis
Renal artery stenosis (RAS) - often caused by drugs e.g. ACEi or NSAIDs

Question 16

Biochemical disturbance in intrinsic renal AKI

Answer 16

Urea rise &laquo_space;creatinine rise with no palpable bladder or kidneys / hydronephrosis
E.g. urea 9 (3-7.5 mmol/L) creatinine 342 (35-125 umol/L)

Question 17

Causes of intrinsic renal AKI (pneumonic)

Answer 17

INTRINSIC
Ischaemia (due to prerenal AKI, causing acute tubular necrosis)
Nephrotoxic antibiotics (gentamycin, vancomycin, tetracyclines e.g. doxycycline)
Tablets (ACEi, NSAIDs)
Radiological contrast
Injury (rhabdomyolysis)
Negatively birefringent crystals (gout)
Syndromes (glomerulonephritidies)
Inflammation (vasculitis)
Cholesterol emboli

Question 18

Biochemical disturbance in postrenal (obstructive) AKI

Answer 18

Urea rise &laquo_space;creatinine rise with palpable bladder or kidneys / hydronephrosis
E.g. urea 9 (3-7.5 mmol/L) creatinine 342 (35-125 umol/L)

Question 19

Causes of postrenal (obstructive) AKI

Answer 19

In lumen: stone or sloughed papilla
In wall: tumour (renal cell or transitional cell carcinoma), fibrosis
External pressure: BPH, prostate Ca, lymphadenopathy, aneurysm