Heterogeneous glycopeptide intermediate Staphylococcus epidermidis isolated from prosthetic joint infections

• Published in: European journal of clinical microbiology & infectious diseases 2014-06, Vol.33 (6), p.911-917
• Main Authors: Tevell, S., Claesson, C., Hellmark, B., Söderquist, B., Nilsdotter-Augustinsson, Å.
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - pharmacology; Antibacterial agents; Antibiotic resistance; Antibiotics; Antibiotics. Antiinfectious agents. Antiparasitic agents; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Diseases of the osteoarticular system; Drug Resistance, Bacterial; Glycopeptides - pharmacology; Health sciences; Hospitals; Humans; Infections; Infectious Diseases; Infektionssjukdomar; Internal Medicine; Joint surgery; Joints - microbiology; Knee; Medical laboratories; Medical Microbiology; Medical sciences; Medicine; Microbial Sensitivity Tests; Microbiology; Mikrobiologi; Miscellaneous. Osteoarticular involvement in other diseases; Pharmacology. Drug treatments; Prostheses; Prosthesis-Related Infections - microbiology; Staphylococcal Infections - microbiology; Staphylococcus epidermidis; Staphylococcus epidermidis - drug effects; Staphylococcus epidermidis - isolation & purification; Sweden; Teicoplanin - pharmacology; Vancomycin - pharmacology
• ISSN: 0934-9723; 1435-4373; 1435-4373
• DOI: 10.1007/s10096-013-2025-3

Methicillin-resistant Staphylococcus epidermidis (MRSE) poses a major problem in prosthetic joint infections (PJIs). Vancomycin is often considered the drug of choice in the empirical treatment of staphylococcal PJIs. As recent decades have seen reports of heterogeneous glycopeptide intermediate S. aureus (hGISA), our aim was to examine the prevalence of heterogeneous glycopeptide intermediate S. epidermidis (hGISE) in PJIs. S. epidermidis isolates ( n  = 122) from 119 patients in three Swedish counties between 1993 and 2012 were included. All were isolated from perioperative tissue samples from revision surgery in clinically verified PJIs. Antimicrobial susceptibility testing against staphylococcal antibiotics was performed. The macromethod Etest (MME) and glycopeptide resistance detection (GRD) Etest were used to detect hGISE. Standard minimal inhibitory concentration (MIC) determination revealed no vancomycin-resistant isolates, while teicoplanin resistance was detected in 14 out of 122 isolates (11.5 %). hGISE was found in 95 out of 122 isolates (77.9 %), 64 out of 67 of isolates with teicoplanin MIC >2 mg/L (95.5 %) and 31 out of 55 of isolates with teicoplanin MIC ≤2 mg/L (56.4 %). Thus, the presence of hGISE cannot be ruled out by teicoplanin MIC ≤2 mg/L alone. Multidrug resistance was detected in 86 out of 95 hGISE isolates (90.5 %) and in 16 out of 27 isolates (59.3 %), where hGISE could not be detected. In conclusion, hGISE detected by MME or GRD was common in this material. However, hGISE is difficult to detect with standard laboratory diagnostic routines. Glycopeptide treatment may not be sufficient in many of these PJIs, even if standard MIC classifies the isolated S. epidermidis as susceptible.