Is Intravenous Immunoglobulin (IVIG) dialyzable in a patient with impaired renal function on chronic dialysis?

Is IVIG Dialyzable?

No, IVIG (Intravenous Immunoglobulin) is not dialyzable due to its large molecular size (approximately 150 kDa), which prevents removal by conventional hemodialysis or peritoneal dialysis membranes.

Molecular Properties and Dialysis Considerations

• IVIG consists of large immunoglobulin G molecules that are too large to pass through standard dialysis membranes, which typically have molecular weight cutoffs well below the size of intact antibodies 1
• The pharmacokinetic properties of IVIG remain unchanged in dialysis patients, as the molecule cannot be cleared through dialysis circuits 1

Critical Implications for Dialysis Patients

Patients on chronic dialysis can safely receive IVIG without concern for drug removal during dialysis sessions, and dialysis timing does not need to be adjusted around IVIG administration 2

Key Management Points:

• No dialysis schedule modification is required when administering IVIG to patients with end-stage renal disease on maintenance dialysis 2
• IVIG dosing does not require adjustment based on dialysis status, as the drug is not removed by dialysis 1
• The standard dosing protocols for IVIG (typically 0.4-2 g/kg depending on indication) apply equally to dialysis-dependent patients 2

Renal Safety Considerations in Dialysis Patients

While IVIG is not dialyzable, important safety considerations exist for patients with impaired renal function:

Risk Profile in Renal Impairment:

• Acute renal failure risk is primarily relevant in patients with residual renal function, not those already on dialysis 1, 3
• Sucrose-containing IVIG formulations historically carried higher nephrotoxicity risk (approximately 88% of ARF cases), though this is less relevant in anuric dialysis patients 4, 5
• The incidence of IVIG-associated renal impairment in patients with residual function ranges from 1.7-6.7% 6

Monitoring Recommendations:

• For dialysis patients with any residual urine output, monitor for volume overload, as IVIG administration adds significant fluid volume 1
• Screen for IgA deficiency before first infusion to prevent anaphylaxis risk 2
• Monitor for thrombotic complications, particularly in patients with cardiovascular comorbidities, as IVIG carries a black box warning for thrombosis and acute renal failure (though the latter applies to those with functioning kidneys) 2

Practical Clinical Algorithm

For patients on chronic hemodialysis or peritoneal dialysis:

1. Administer IVIG at standard doses without adjustment for dialysis status 1
2. Schedule IVIG infusion at any time relative to dialysis sessions—timing is clinically irrelevant 2
3. Monitor for volume overload if residual urine output exists 1
4. Watch for infusion-related reactions (headache, fever) but not for drug removal during subsequent dialysis 2

For patients with CKD not yet on dialysis (GFR <30 mL/min):

1. Consider using non-sucrose-stabilized IVIG formulations to minimize nephrotoxicity risk 4
2. Ensure adequate hydration and avoid concurrent nephrotoxic medications 1, 3
3. Monitor serum creatinine closely within 2-5 days post-infusion, as 85% of IVIG-related renal impairment occurs in this window 3

Common Pitfalls to Avoid

• Do not delay or withhold IVIG in dialysis patients due to concerns about drug removal—the medication is not dialyzable and will remain therapeutic 2, 1
• Do not schedule "extra" dialysis sessions to remove IVIG—this is ineffective and unnecessary 2
• Do not reduce IVIG doses in anuric dialysis patients based solely on dialysis status, as pharmacokinetics are unaffected by dialysis 1
• In patients with residual renal function approaching dialysis (GFR 5-15 mL/min), exercise caution with high-dose IVIG (>1 g/kg) and consider nephrology consultation before administration 1, 3