Interference with vancomycin fluorescence polarisation immunoassay in a nonuraemic patient

Commercially available immunoassays for vancomycin have been reported to overestimate serum vancomycin concentrations by varying degrees in patients with renal impairment, particularly those on peritoneal dialysis, by interference with crystalline degradation product-1 (CDP-1). To date this interference has not been reported in any other patient population. This report describes vancomycin fluorescence polarisation immunoassay (FPIA) interference in a patient with only mildly impaired renal function. At this time it is not possible to confirm that the interference was caused by CDP-1.