Mazzariol A, Koncan R, Bahar G, Cornaglia G
Departimento di Patologia, Sezione di Microbiologia, Univerdità degli Studi di Verona, Strada Le Grazie 8, 37134 Verona, Italy.
J Chemother. 2007 Oct;19(5):500-7. doi: 10.1179/joc.2007.19.5.500.
687 isolates of Streptococcus pyogenes and 600 isolates of Streptococcus pneumoniae , isolated over the period 2002-2003 from specimens of different human origin obtained in 16 different Italian centres, were assayed for their susceptibilities to different macrolides and to telithromycin, and were investigated by PCR to detect their different erythromycin resistance genes. 25.5% of the S. pyogenes isolates proved resistant to erythromycin, as well as to clarithromycin and azithromycin. 6.6% of the isolates proved non-susceptible to clindamycin. 4.9% of the isolates were non-susceptible to telithromycin. 22.3% of all erythromycin-resistant isolates exhibited cMLS B resistance, 50.3% iMLS B resistance, and 27.4% Mtype resistance. All cMLS B strains had the erm(B) gene, all M strains had the mef (A) gene, and no resistance genes were found in the erythromycin-susceptible strains. Roughly one quarter of the iMLS(B) strains had erm(A) and roughly three quarters erm(B). 35.2% of the S. pneumoniae isolates proved resistant to erythromycin, and virtually all of them also proved resistant to clarithromycin and azithromycin, too. Only 6.0% of the pneumococcal isolates were resistant to penicillin and a further 11.0% were intermediate. Only 0.2% of the isolates were nonsusceptible to telithromycin. 65.9% of all erythromycin-resistant S. pneumoniae isolates had cMLS B resistance, 18.0% had iMLS B resistance, and 16.1% had M-type resistance. All the MLS B-resistant isolates had an erm(B) gene, and all the M-type isolates had a mef gene. We conclude that macrolide resistance of streptococci still persists in Italy with incidences as high as 40%, more often than not being characterised by the MLS B phenotype. The ketolide telithromycin, structurally related to macrolides and most likely to substitute for them in a number of clinical uses, is confirmed as being extremely active even against recent clinical streptococcal isolates.
2002年至2003年期间，从意大利16个不同中心采集的来自不同人类来源的标本中分离出687株化脓性链球菌和600株肺炎链球菌，检测它们对不同大环内酯类药物和泰利霉素的敏感性，并通过聚合酶链反应（PCR）检测其不同的红霉素耐药基因。25.5%的化脓性链球菌分离株对红霉素、克拉霉素和阿奇霉素耐药。6.6%的分离株对克林霉素不敏感。4.9%的分离株对泰利霉素不敏感。所有红霉素耐药分离株中，22.3%表现为cMLS B耐药，50.3%为iMLS B耐药，27.4%为M型耐药。所有cMLS B菌株都有erm(B)基因，所有M菌株都有mef(A)基因，而红霉素敏感菌株中未发现耐药基因。大约四分之一的iMLS(B)菌株有erm(A)基因，大约四分之三有erm(B)基因。35.2%的肺炎链球菌分离株对红霉素耐药，实际上所有这些分离株对克拉霉素和阿奇霉素也耐药。只有6.0%的肺炎球菌分离株对青霉素耐药，另有11.0%为中介型。只有0.2%的分离株对泰利霉素不敏感。所有红霉素耐药的肺炎链球菌分离株中，65.9%有cMLS B耐药，18.0%有iMLS B耐药，16.1%有M型耐药。所有MLS B耐药分离株都有erm(B)基因，所有M型分离株都有mef基因。我们得出结论，链球菌的大环内酯类耐药在意大利仍然存在，发生率高达40%，通常以MLS B表型为特征。酮内酯类泰利霉素与大环内酯类结构相关，很可能在许多临床应用中替代它们，即使对近期临床分离的链球菌也被证实具有极强的活性。
