Linezolid as a potential alternative to glycopeptide in treating Enterococcus faecium suspected cyst infection in a hemodialysis patient with autosomal-dominant polycystic kidney disease: A case report

Autosomal-dominant polycystic kidney disease is a clinically significant disorder associated with progressive renal impairment. In these patients, cyst infection is an important but variably occurring complication, and optimal antibiotic selection remains challenging owing to the limited available evidence and restricted antibiotic penetration into cysts. An 81-year-old Japanese man with autosomal-dominant polycystic kidney disease undergoing maintenance hemodialysis presented with fever and a suspected cyst infection. Blood cultures showed the fluoroquinolone-resistant Enterococcus faecium . Vancomycin was contraindicated due to allergy, and teicoplanin was ineffective. Oral linezolid was initiated, resulting in clinical improvement. However, treatment was discontinued after 15 days of therapy (on hospital day 27) because of grade 1 thrombocytopenia. This case contributes to the limited clinical evidence in this field and highlights the potential role of linezolid in the management of Enterococcus faecium suspected cyst infections in autosomal-dominant polycystic kidney disease when glycopeptides are ineffective or contraindicated.