Actinomyces species: A Danish Survey on Human Infections and Microbiological Characteristics

Department of Bacteriology, Mycology and Parasitology, Statens Serum Institute, Copenhagen, Departments of Clinical Microbiology.
The Open Microbiology Journal 02/2009; 3(1):113-20. DOI: 10.2174/1874285800903010113
Source: PubMed


This study compared phenotypic and genotypic identification of Actinomyces strains, tested susceptibility to antibiotics and evaluated their clinical importance. Thirty-four Actinomyces strains were examined; sixteen type strains, and 18 clinical strains from different hospitals in Denmark from the period 2003-2005. Partial 16S rDNA sequencing using a stretch of 526 bases was used for genotypic identification. Susceptibility testing was done by E-test. The antibiotics examined were: benzylpenicillin, piperacillin with tazobactam, ceftriaxone, meropenem, erythromycin, clindamycin, linezolid, moxifloxacin, tetracycline and tigecycline. Clinical parameters were obtained by reviewing patient records. There was poor agreement between the phenotypic and genotypic identification. Phenotypic tests were helpful in identifying strains closely related by DNA sequences. The strains were sensitive to the examined antibiotics except for moxifloxacin to which most strains were resistant, and a few strains were resistant to meropenem and tetracycline. The clinical strains were from many different types of infections and locations. None of the patients was described as having typical actinomycetic lesions, and an apparently good outcome was obtained with different treatment regimens.

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Available from: Jens Jørgen Christensen, Jan 15, 2014
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    • "One case of cystitis was reported in a revision of Actinomyces spp. infections in Denmark that was treated with a short-course of antimicrobials (cefuroxime and meropenem for 9 days) [6]. "
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    IDCases 12/2014; 1(3). DOI:10.1016/j.idcr.2014.05.002
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    • "Possible explanations for treatment failure are drug-resistant co-pathogens and poor penetration of the drug caused by avascularity and induration of the infected area [14]. Although reported antimicrobial susceptibility tests indicate that most Actinomyces are susceptible to penicillin and amoxicillin, Actinomyces may acquire antibiotic resistance during antibiotic treatment [15,16]. "
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    • "Pulmonary actinomycosis is a rare bacterial infection that is sometimes difficult to diagnose. Currently, PCR following 16S rRNA gene sequencing is the preferred method of detecting Actinomyces in clinical material (Hansen et al., 2009). This disease generally results in non-specific respiratory symptoms and various radiological findings. "
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