Aim: The aim of this study was to determine the incidence of
macrolide-lincosamide-streptogramin B (MLSB) resistance in
staphylococcal isolates from various clinical samples.
Methods: In this study, we included a total of 100 staphylococcal
isolates, 35 Staphylococcus aureus and 65 coagulase-negative
staphylococci (CNS), from specimens obtained from patients
followed up in our hospital between 2009 and 2010. Methicillin
resistance of these isolates was determined using cefoxitin disc
diffusion method. MLSB resistance was investigated by D-test
method using erythromycin and clindamycin disks.
Results: Of 35 S. aureus isolates, 14 were methicillin-resistant
(MRSA) and 21 were methicillin-sensitive (MSSA). Of 65 CNS
isolates, 41 were methicillin-resistant (MRCNS) and 24 were
methicillin-sensitive (MSCNS). In 79 strains, there was at least
one MLSB resistance phenotype. The most frequent resistance
phenotypes were inducible (35%) and constitutive (30%) among
all isolates, while the constitutive one was more common in S.
aureus strains (62%).
Conclusion: Since the resistant community- and hospitalacquired
staphylococcal infections have become a therapeutic
problem, it is very important to detect MLSB resistance routinely
in microbiology laboratories. D-test is a cheap and reliable
diagnostic method which can be performed in every laboratory.
In order to prevent treatment failure, D-test should be routinely
used and the results should be reported to the clinician before
starting a therapy with MLSB group of antibiotics. (The Me di cal
Bul le tin of Ha se ki 2011; 49: 102-4