Litholapaxy Safety After Amphotericin B-Induced AKI
Litholapaxy is generally safe a couple years after amphotericin B-related AKI, provided the patient has achieved adequate renal recovery with serum creatinine returned to near baseline, and appropriate perioperative nephroprotective measures are implemented. 1
Assessing Current Renal Function
The critical first step is determining the degree of kidney recovery from the prior amphotericin B injury:
- Compare current serum creatinine to pre-amphotericin baseline values to quantify recovery status 1
- If creatinine remains >1.5× baseline, the patient remains in the persistent acute kidney disease (AKD) phase and is at maximum vulnerability—litholapaxy should be deferred in this scenario 1
- Patients who experienced amphotericin B-induced AKI remain at heightened risk for recurrent kidney injury even after apparent recovery, as the vulnerable period extends well beyond the acute phase 1
Understanding the Underlying Risk
The kidney damage from amphotericin B creates lasting vulnerability:
- Amphotericin B causes direct tubular damage and renal vasoconstriction, with some permanent impairment often occurring, especially with large cumulative doses (>5g) or concurrent nephrotoxic agents 1, 2
- Each additional nephrotoxin exposure increases AKI odds by 53%, and combining multiple nephrotoxic insults more than doubles the risk 1
- The nephrotoxicity is related to both direct action on renal tubules and drug-induced renal vasoconstriction 3
Mandatory Perioperative Protective Strategies
If proceeding with litholapaxy after confirming adequate renal recovery, implement these evidence-based protections:
Medication Management
- Discontinue all non-essential nephrotoxic medications including NSAIDs, diuretics, and aminoglycosides 1
- Avoid the "triple whammy" combination of NSAIDs, diuretics, and ACE inhibitors/ARBs in the perioperative period, as this pharmacodynamic interaction dramatically increases AKI risk 1
- Prior treatment with ACE inhibitors/ARBs or carbapenems is associated with higher AKI rates 4
Volume and Hemodynamic Optimization
- Administer IV volume expansion with isotonic sodium chloride or sodium bicarbonate rather than oral fluids alone 1
- Ensure adequate volume repletion and avoid hypotension during the procedure, as hemodynamic instability compounds nephrotoxic risk 1
- Target mean arterial pressure >65 mmHg if hemodynamic support is required 1
Contrast Considerations
- Use the lowest possible contrast dose or consider contrast-free imaging alternatives when feasible 1
- Screen for pre-existing kidney impairment before any procedure requiring contrast administration 1
Absolute Contraindications to Proceeding
Do not proceed with litholapaxy if:
- Serum creatinine remains >1.5× baseline from the amphotericin-induced AKI 1
- Multiple concomitant nephrotoxins cannot be discontinued 1
- Hemodynamic instability or volume depletion cannot be corrected pre-procedure 1
Clinical Context
Two years post-AKI provides substantial time for renal recovery in most patients. The amphotericin B nephrotoxicity is usually reversible in most patients, though some degree of permanent impairment may persist 3. The key is confirming that recovery has occurred through objective creatinine comparison, rather than assuming safety based solely on time elapsed.
The evidence shows that even liposomal amphotericin B formulations, which are less nephrotoxic than conventional preparations, still cause renal injury in 19-50% of patients 2. This underscores that the initial insult was significant and warrants ongoing caution with subsequent nephrotoxic exposures.