Rusty peritoneal dialysis fluid after intravenous administration of iron dextran

Area of Science:

• Nephrology
• Pharmacology
• Clinical Medicine

Background:

• Peritoneal dialysis (PD) is a crucial treatment for end-stage renal disease.
• Management of concurrent conditions like peritonitis requires careful drug selection.
• Iron dextran is used for iron deficiency anemia, while vancomycin and rifampicin treat bacterial peritonitis.

Observation:

• A patient undergoing PD for peritonitis presented with rusty-colored dialysate fluid post-intravenous iron dextran administration.
• The fluid discoloration was not attributable to erythrocytes or free hemoglobin.
• Iron was detected in the dialysate, decreasing as the discoloration faded over 24 hours.

Findings:

• In vitro experiments showed iron dextran alone did not discolor PD fluid.
• Rifampicin alone caused mild orange discoloration.
• A combination of iron dextran and rifampicin at clinical concentrations produced significant rusty discoloration, mimicking the patient's presentation.

Implications:

• The study suggests a drug interaction between iron dextran and rifampicin can cause peritoneal dialysate discoloration.
• This finding is crucial for clinicians managing PD patients receiving both iron supplementation and rifampicin.
• Awareness of this interaction can prevent misdiagnosis and unnecessary investigations for hematuria or hemolysis.