Granlund Margareta, Åberg Carola Höglund, Johansson Anders, Claesson Rolf
Department of Clinical Microbiology, Umeå University, S-90187 Umeå, Sweden.
Division of Molecular Periodontology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden.
Antibiotics (Basel). 2022 Feb 27;11(3):317. doi: 10.3390/antibiotics11030317.
The Aggregatibacter actinomycetemcomitans JP2 genotype is associated with high leukotoxin production and severe (aggressive) periodontitis. The aim of this study was to compare the antimicrobial susceptibility of JP2 and non-JP2 genotype strains. Minimal inhibitory concentrations (MICs) of 11 antimicrobials were determined for 160 A. actinomycetemcomitans of serotype a, b, or c, mostly isolated in Sweden or Ghana. MIC distributions for benzylpenicillin and fusidic acid revealed a more susceptible subpopulation for 38 serotype b strains, including the 32 of the JP2 genotype, with a benzylpenicillin MIC range of 0.125−0.5 mg/L. In contrast, benzylpenicillin MIC ≤ 16 mg/L was the estimated 99.5% epidemiological cutoff (ECOFF) of all strains. Beta-lactamase production was not detected. The fusidic acid MIC distribution of 11 strains of Aggregatibacter aphrophilus agreed with that found in non-JP2 strains. Cefotaxime, meropenem, levofloxacin, and trimethoprim−sulfamethoxazole MICs were all ≤0.25 mg/L, while MIC90 values for amoxicillin, azithromycin and tetracycline were 1 mg/L. Metronidazole MICs varied between 0.5 and >256 mg/L. The discrepant findings indicate that A. actinomycetemcomitans may be divided into two separate wild types, with a suggested intrinsic reduced susceptibility for benzylpenicillin in the majority of non-JP2 genotype strains. Possible implications for the treatment of A. actinomycetemcomitans infections are discussed.
伴放线聚集杆菌JP2基因型与高白细胞毒素产生及重度（侵袭性）牙周炎相关。本研究的目的是比较JP2和非JP2基因型菌株的抗菌敏感性。对160株血清型a、b或c的伴放线聚集杆菌测定了11种抗菌药物的最低抑菌浓度（MIC），这些菌株大多分离自瑞典或加纳。苄青霉素和夫西地酸的MIC分布显示，38株血清型b菌株（包括32株JP2基因型菌株）存在更易感亚群，苄青霉素MIC范围为0.125−0.5mg/L。相比之下，所有菌株的苄青霉素MIC≤16mg/L为估计的99.5%流行病学临界值（ECOFF）。未检测到β-内酰胺酶产生。11株嗜沫聚集杆菌的夫西地酸MIC分布与非JP2菌株中的情况一致。头孢噻肟、美罗培南、左氧氟沙星和甲氧苄啶-磺胺甲恶唑的MIC均≤0.25mg/L，而阿莫西林、阿奇霉素和四环素的MIC90值为1mg/L。甲硝唑的MIC在0.5至>256mg/L之间变化。这些不一致的结果表明，伴放线聚集杆菌可能分为两种不同的野生型，大多数非JP2基因型菌株对苄青霉素的固有敏感性可能降低。文中讨论了对伴放线聚集杆菌感染治疗的可能影响。
