How to manage a patient with severe renal impairment?

Management of Severe Renal Impairment (eGFR <28 ml/min/1.73 m², Creatinine 1.8)

Patients with severe renal impairment (eGFR <30 ml/min/1.73 m²) should be treated in expert centers with close monitoring by a multidisciplinary team to optimize outcomes and prevent further deterioration of kidney function. 1

General Management Principles

• Severe renal impairment (eGFR <30 ml/min/1.73 m²) requires careful medication management as many drugs are eliminated by the kidneys and may accumulate to toxic levels 1
• Patients should be monitored closely with regular assessment of renal function, especially when starting new medications 1
• Drug dosing should be adjusted based on the degree of renal impairment to prevent adverse effects 2
• Consider consultation with nephrology for specialized management 1

Medication Management

Medications to Avoid or Use with Caution

• Metformin is contraindicated in patients with eGFR <30 ml/min/1.73 m² due to increased risk of lactic acidosis 3
• Sofosbuvir-based regimens should be used with extreme caution in patients with severe renal impairment as they are primarily eliminated by the renal route 1
• Ribavirin requires significant dose reduction (200 mg/day, 200 mg every other day, or 200 mg three times weekly after hemodialysis) and hematopoietic support in severe renal impairment 1

Medication Dose Adjustments

• For patients with hepatitis C and severe renal impairment, sofosbuvir-free regimens are preferred 1

• Recommended alternatives include:

  • Grazoprevir/elbasvir for genotype 1 and 4 patients 1
  • Glecaprevir/pibrentasvir for patients with genotypes 1-6 1
  • Ritonavir-boosted paritaprevir, ombitasvir and dasabuvir for genotype 1 patients 1

• For colchicine (used in gout prophylaxis), reduce dose to 0.3 mg daily in severe renal impairment to maintain therapeutic levels and avoid toxicity 2

Renal Replacement Therapy Considerations

• For patients approaching end-stage renal disease, evaluate candidacy for dialysis or kidney transplantation 1
• For patients already on dialysis, consider the timing of treatments for comorbid conditions (e.g., hepatitis C) in relation to potential kidney transplantation 1
• Plasma exchange may be beneficial for selected patients with rapidly progressive severe renal disease to improve renal survival 1

Special Considerations for Multiple Myeloma with Renal Impairment

• For multiple myeloma patients with acute kidney injury, rapid reduction of serum free light chains is critical for renal recovery 1
• Preferred treatment regimen includes:
  • Daratumumab combined with bortezomib, cyclophosphamide, and dexamethasone (D-VCD) 1
  • Bortezomib is preferred as it is not renally cleared or nephrotoxic 1
  • Avoid lenalidomide in the upfront setting due to requirement for dose adjustment 1
• Plasma exchange should be considered to rapidly reduce serum free light chain concentration 1

Monitoring and Follow-up

• Obtain eGFR at least annually in all patients with renal impairment, and more frequently in high-risk patients 3
• Monitor for drug toxicity, especially when using medications that require renal clearance 4
• Be aware that eGFR and serum creatinine may not accurately reflect kidney function in patients with low muscle mass, requiring additional assessment methods 4
• Implement computer-based systems for drug dosage adjustment to reduce inappropriate prescribing in renal impairment 5

Common Pitfalls to Avoid

• Relying solely on serum creatinine or eGFR without considering clinical context, especially in patients with low muscle mass 4
• Failing to adjust medication doses appropriately, which can lead to toxicity 5, 2
• Using nephrotoxic medications that may further worsen kidney function 1
• Overlooking drug-drug interactions that may compound renal toxicity 3

Remember that management of severe renal impairment requires a careful balance between treating the underlying condition effectively while avoiding further kidney damage through medication toxicity.