A complicated case of Serratia marcescens catheter-related bloodstream infection misdiagnosed as hypersensitivity reactions to bicarbonate dialysate containing acetate.

Recurrent fever during/post-dialysis can occur due to infectious or non-infectious causes. We present the case of a 79-year-old patient who had persistent post-dialysis fever after long-term tunneled central venous catheterization with acetate-containing bicarbonate dialysate. Drug-induced lymphocyte stimulation test (DLST) was positive for acetate dialysate, and he was suspected of having acetate dialysate-induced hypersensitivity reaction. However, switching to acetate-free dialysate did not attenuate the fever. Since Serratia marcescens had been isolated twice from the blood, catheter-related bloodstream infection (CRBSI) was suspected. The culture of the catheter tip confirmed CRBSI caused by S. marcescens. Elevation of β-d-glucan levels and appearance of pulmonary nodular shadow on chest computed tomography images indicated complicated fungal infections. Administration of antibiotics and antifungals led to resolution of the pulmonary nodular shadow with attenuation of fever and C-reactive protein levels. DLST for acetate dialysate was negative, and its reuse did not aggravate the symptoms; hence, the first result was considered false-positive. An indwelling catheter is a risk factor for S. marcescens-related CRBSI, which leads to post-dialysis fever. Hypersensitivity reactions to dialysates must be diagnosed considering the clinical course and DLST results.