QW59 January 2026

Question

Clinical Case Scenario

A 70 kg 56- yr old female with acute myeloid leukaemia on induction chemotherapy with VCR- daunorubicin regimen is neutropenic day 11 following chemotherapy and admitted to ICU with confusion, facial swelling and diplopia. CECT brain reveals rhino cerebral mucormycosis and he is commenced on liposomal Amphotericin B ( LAMB) at 5mg/kg intravenous. He develops ST segment depression and T wave inversions in ECG. The following changes are noted on blood and urine parameters day 7 of therapy:

Urine output: 7500 ml/ day
Serum creatinine e: 88-242 µmol/L
Serum potassium: 4.3->3.6->2.8mmol /L
Serum magnesium :0.45 mmol /L
Serum bicarbonate 18 mol/L
Urinalysis: bland; nil casts
Renal ultrasound: normal

Which of the following statements are false regarding the mechanism of nephrotoxicity:

A) The hydrophobic part of LAMB binds with sterol and induces pore formation in renal tubules allowing extravasation of electrolytes into the ECF space of tubular cells and hence urinary loss by diffusion down a concentration gradient

B) LAMB causes resistance to arginine vasopressin and hence concentrating ability of the collecting ducts is lost precipitating nephrogenic diabetes insipidus

C) LAMB induced hypokalaemia is partially mediated through upregulation of aldosterone receptors in the distal tubules and collecting ducts causing inability to reabsorb sodium and facilitating renal potassium loss

D) LAMB mediated AKI is partly due to the reduction in glomerular filtration GFR associated with renal vasoconstriction