s. haemolyticus 1

Journal of Antimicrobial Chemotherapy (2000) 45, 401–412 JAC Correspondence Septicaemias caused by a strain of Staphylococcus haemolyticus exhibiting intermediate susceptibility to teicoplanin in multiple intensive care unit patients J Antimicrob Chemother 2000; 45: 410–411 J. H. Sloos*, L. Dijkshoorn and C. P. A. van Boven Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands *Correspondence address. Laboratory for Clinical Microbiology, Medical Center Alkmaar, PO Box 501, 1800 AM Alkmaar, The Netherlands. Tel: +31-72-5483671; Fax: +31-72-5482186; E-mail: [email protected] Sir, Figure. PFGE patterns of eight S. haemolyticus isolates re- Septicaemias caused by coagulase-negative staphylococci covered from blood cultures obtained from eight patients. Lanes (CoNS), including Staphylococcus haemolyticus, are com- 1–3: three isolates exhibiting intermediate susceptibility to teico- mon in neutropenic patients. Since these bacteria are often planin which were recovered from patients in the intensive resistant to both -lactam antibiotics and aminoglycosides, care unit during a 1 month period. Lanes 4–8: five teicoplanin- the empirical therapy of choice is a glycopeptide, either susceptible isolates that were from patients in various other vancomycin or teicoplanin. Teicoplanin is less active in vitro wards and were not temporally related. M: marker strain. against isolates of S. haemolyticus compared with other CoNS and there have been reports of treatment failures in method described previously.6 The Figure demonstrates neutropenic patients who had received the antibiotic for the PFGE patterns for the eight S. haemolyticus isolates septicaemias caused by bacteria belonging to this species.1,2 collected during 1994. The pattern of each of the five In a recent study we compared the MICs of vancomycin teicoplanin-susceptible isolates was unique, whereas those and teicoplanin for 201 clinical isolates of CoNS recovered of the three intermediately susceptible isolates were indis- at the Leiden University Medical Center in 1985 and in tinguishable, suggesting that the latter isolates belonged to 1994.3 In 1994 we identified eight isolates of S. haemo- a single clone. lyticus, three of which exhibited intermediate susceptibility to teicoplanin (MICs 9, 9 and 10 mg/L, respectively) accord- To the best of our knowledge this is the first report of ing to MIC breakpoints recommended by the National septicaemias in multiple patients caused by one S. haemo- Committee for Clinical Laboratory Standards.4 The three lyticus strain exhibiting intermediate susceptibility to isolates, all of which were susceptible to vancomycin, were teicoplanin. The spread of strains of S. haemolyticus with recovered during a 1 month period from blood cultures reduced susceptibilities to teicoplanin among immuno- obtained from three patients in the intensive care unit. compromised patients is a worrying development and the All three patients suffered septicaemia according to CDC observation reported here suggests that this glycopeptide criteria.5 The remaining five isolates were recovered from should be used with caution as empirical therapy for such patients in various other wards and were temporally un- patients with septicaemias caused by CoNS. related. References In order to determine whether the three strains exhibit- ing intermediate susceptibility to teicoplanin were clonally 1. Spanik, S., Trupl, J., Studena, M. & Krcmery, V. (1997). Break- related, DNA extracted from these bacteria was analysed through nosocomial bacteraemia due to teicoplanin-resistant by pulsed-field gel electrophoresis (PFGE) according to a 410 © 2000 The British Society for Antimicrobial Chemotherapy

Correspondence Staphylococcus haemolyticus in five patients with acute leukaemia. Performance Standards for Antimicrobial Susceptibility Testing— Journal of Hospital Infection 35, 155–9. Sixth Informational Supplement: Approved Standard M100-S6. NCCLS, Wayne, PA. 2. Cunningham, R., Gurnell, M., Bayston, R., Cockayne, A. & Shel- ton, A. (1997). Teicoplanin resistance in Staphylococcus haemolyti- 5. Garner, J. S., Jarvis, W. R., Emori, T. G., Horan, T. C. & Hughes, cus, developing during treatment. Journal of Antimicrobial J. M. (1988). CDC definitions for nosocomial infections. American Chemotherapy 39, 438–9. Journal of Infection Control 16, 128–40. 3. Sloos, J. H., van de Klundert, J. A. M., Dijkshoorn, L. & van 6. Sloos, J. H., Horrevorts, A. M., van Boven, C. P. A. & Dijkshoorn, Boven, C. P. A. (1998). Changing susceptibilities of coagulase- L. (1998). Identification of multiresistant Staphylococcus epiderm- negative staphylococci to teicoplanin in a teaching hospital. Journal idis in neonates of a secondary care hospital using pulsed field of Antimicrobial Chemotherapy 42, 787–91. gel electrophoresis and quantitative antibiogram typing. Journal of Clinical Pathology 51, 62–7. 4. National Committee for Clinical Laboratory Standards. (1995). 411