Staphylococcus epidermidis

A multidrug-resistant S. epidermidis clone (ST5R, cfr on plasmid pMB151a, also resistant to methicillin, levofloxacin, trimethoprim-sulfamethoxazole, and gentamicin) caused 31 of 39 (79%) linezolid-resistant bloodstream infections in leukemia patients at a major cancer center; prior linezolid use in the preceding 90 days was significantly more common in patients with linezolid-resistant vs linezolid-susceptible ST5 infections (79% vs 19%; P<0.001), and cumulative linezolid exposure was significantly higher (median 12 vs 0 days; P<0.001), indicating that both nosocomial clonal transmission and antibiotic selection pressure drove invasive multidrug-resistant S. epidermidis emergence.

PMID: 29546356

D000073602 Antimicrobial Stewardship D024901 Drug Resistance, Multiple, Bacterial D000069349 Linezolid D013203 Staphylococcal Infections D013212 Staphylococcus epidermidis H01401 Methicillin-resistant Staphylococcus epidermidis (MRSE) infection

Prolonged linezolid use was associated with progressive domination of the gastrointestinal microbiome by cfr-containing S. epidermidis in leukemia patients undergoing induction chemotherapy: 10 of 98 patients developed staphylococcal GI emergence (≥30% consecutive 16S rRNA reads mapping to Staphylococcus from a ≤10% baseline), all 10 had received linezolid before staphylococcal proliferation (P<0.001 Mann-Whitney for linezolid duration in emergence vs non-emergence patients), and marked increases in cfr abundance in stool were confirmed by RT-qPCR during or following linezolid therapy in 5 of 6 confirmed S. epidermidis cases.

PMID: 29546356

D024901 Drug Resistance, Multiple, Bacterial D005243 Feces D000069349 Linezolid D064307 Microbiota D013212 Staphylococcus epidermidis H01401 Methicillin-resistant Staphylococcus epidermidis (MRSE) infection

Staphylococcus epidermidis caused a catheter-related bloodstream infection during conditioning chemotherapy in a 20-year-old immunocompromised patient undergoing allogeneic HSCT for B-cell ALL, treated empirically with meropenem, vancomycin, and liposomal amphotericin B.

PMID: 40544256