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ABSTRACT: Hidradenitis suppurativa (HS) is a cicatrising and persistent disease of apocrine gland-bearing areas in adults. The severity of this condition varies from a few suppurating lesions to widespread, disabling disease. The aetiology is obscure, but suggested contributory factors include a genetic predisposition, comedones occluding the pilosebaceous apparatus, bacterial infections, and hormonal factors. Treatment consists mainly of surgery, while medical therapies serve principally as adjunct therapy.
The aim of the study was to determine the number and type of bacteria circulating in the bloodstream in patients with HS undergoing surgical treatment with a carbon dioxide laser stripping-secondary intention technique.
Twenty-one patients (20 females and 1 male, mean age 36, range 20-55 years) were included in the study. One blood sample (8.3 ml) was taken before surgery, one during the operation and the last one 10 min after surgery. Five healthy persons (all females, mean age 36, range 23-48 years) not undergoing any operation were used as the controls. The blood was cultured by a lysis-filtration technique which had been shown to be very sensitive. Since the filter catches the microorganisms and colonies are formed during culturing, the number of bacteria in the samples is easily determined.
In 6 patients, all samples were negative, which indicates that the method of surgery itself caused no spread of bacteria from the lesions. Bacterial growth in the first blood sample was found in 9 patients, from the second sample in 10 and from the third one in 6. In 1 patient, bacteria were detected in three samples. At least 12 bacterial species were identified. The dominating bacteria were coagulase-negative staphylococci of which most were subtyped as Staphylococcus warneri. Among the anaerobic microorganisms, Propionibacterium acnes and P.granulosum were the most frequently isolated bacteria. The bacterial findings in the blood samples accord well with the results from a previous study in which cultures were taken from the deep parts of the HS lesions. In the 5 controls, no microbial growth was detected.
The carbon dioxide laser stripping technique caused no additional spread of bacteria into the bloodstream. The evaluation of cultures containing microorganisms from normal skin flora is controversial. Since the bacteria encountered in this study are in close agreement with the findings in cultures from the deeper parts of HS lesions they seem to be relevant. The growth of bacteria in the first blood sample taken before surgery may indicate that some of these patients have bacteria continuously circulating in their blood.
Dermatology 02/2006; 213(4):305-12. · 2.05 Impact Factor
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ABSTRACT: Nitroimidazole resistance (nim) genes were detected in 2% of 1,502 clinical Bacteroides fragilis group strains isolated from 19 European countries, and a novel nim gene was identified. High metronidazole resistance could be induced in nim-positive strains, which emphasizes the importance of acknowledging metronidazole resistance in the clinical setting.
Antimicrobial Agents and Chemotherapy 04/2005; 49(3):1253-6. · 4.84 Impact Factor
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ABSTRACT: The beta-lactam antibiotics are the most widely used of all the groups of antimicrobials, but beta-lactam resistance is increasingly common among members of the Bacteroides fragilis group. Three major mechanisms are involved in beta-lactam resistance, and they act together in certain instances. In the present study, 2 resistant mutants (238m and 1186m) of Bacteroides thetaiotaomicron, obtained from clinical isolates (238 and 1186) by selection with increasing concentrations of cefoxitin, showed decreased susceptibilities to cefoxitin and other beta-lactam antibiotics. Alterations in both penicillin-binding proteins (PBPs) and outer-membrane proteins (OMPs) were observed in the mutants in comparison with their parent strains. The similar alteration in OMPs was also observed in clinical isolates. In conclusion, the beta-lactam-resistant mutants of B. thetaiotaomicron with deficiency in both PBPs and OMPs can be selected for by exposure to cefoxitin, and several mechanisms are involved in the beta-lactam resistance in the strains investigated.
Clinical Infectious Diseases 10/2002; 35(Suppl 1):S47-53. · 9.15 Impact Factor
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ABSTRACT: Beta-lactam antibiotics and 5-nitroimidazoles have been extensively used against anaerobic bacteria. However, antibiotic resistance is increasingly common among anaerobic Gram-negative bacilli. The classical mechanisms of resistance to beta-lactams are, (1) production of beta-lactamases; (2) alteration of penicillin-binding proteins (PBPs); and (3) changes in outer membrane permeability to beta-lactams. The 5-nitroimidazole molecule is a prodrug whose activation depends upon reduction of the nitro group in the absence of oxygen. Decreased uptake and altered reduction are believed to be responsible for metronidazole resistance. Five nim genes (A, B, C, D and E) have been identified in Bacteroides fragilis group spp. that confer resistance to 5-nitroimidazole antibiotics. Knowledge of the status and the mechanisms of resistance is critical for both the selection of antimicrobial therapy and the design of new antimicrobial agents. The purpose of this article is to review the mechanisms for and the prevalence of beta-lactam and metronidazole resistance in strains belonging to the B. fragilis group.
International Journal of Antimicrobial Agents 06/2002; 19(5):361-70. · 4.13 Impact Factor
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Clinical Infectious Diseases - CLIN INFECT DIS. 01/2002; 35.
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ABSTRACT: Objective: To investigate the imipenem and metronidazole resistance profiles of Bacteroides fragilis group strains in fecal samples and to detect the resistance genes (ccrA and nim) coding for imipenem and metronidazole resistance in B. fragilis group strains.Methods: In total, 925 fecal samples, 729 from consecutive diarrhea patients and 196 from healthy controls, were collected at Huddinge University Hospital in 1997. A modified disk diffusion method was employed to screen for imipenem-resistant and metronidazole-resistant B. fragilis group strains. In strains considered resistant by the modified disk diffusion method, the minimum inhibitory concentrations (MICs) were further determined by the agar dilution method. PCR assays were used to detect the carbapenem-hydrolyzing metallo-β-lactamase gene (ccrA) and the 5-nitroimidazole resistance genes (nim) in pure cultures (purePCR), directly from fecal samples through direct broth enrichment (dirPCR) and by immunomagnetic separation (imsPCR).Results: Two imipenem-resistant B. fragilis strains, one of which was simultaneously resistant to metronidazole, and two B. fragilis group strains with MICs near the breakpoint for metronidazole resistance, were isolated from the fecal samples of diarrhea patients. The ccrA gene was identified in all the imipenem-resistant B. fragilis strains by purePCR, dirPCR and imsPCR. The nim genes were also detectable by these PCR assays.Conclusions: The incidences of imipenem-resistant and metronidazole-resistant B. fragilis group strains were low in the investigated diarrhea patients. Simultaneous resistance to imipenem and metronidazole is of great concern in clinical medicine, and the proposed PCR assays may be useful in epidemiologic studies of distribution of resistance genes in the fecal microflora.
Clinical Microbiology and Infection 11/1999; 5(12):753 - 758. · 4.54 Impact Factor
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ABSTRACT: OBJECTIVE: Several small, 15-residue peptides that contain portions of the amino acid sequences of both cecropin A and melittin have previously been shown to have broad-spectrum antibacterial activities against aerobic microorganisms, with no undesirable hemolytic properties. It would also be useful to know what effect these hybrid peptides have on anaerobic bacteria. METHODS: The minimum inhibitory concentrations of one hybrid, CA(1--7)M(2--9)NH2, were compared with those of seven other antimicrobial agents against 111 clinical anaerobic strains; Bacteroides fragilis, 24 strains; other Bacteroides fragilis group, 14 strains; other Bacteroides species, 13 strains; Fusobacterium nucleatum, six strains; Clostridium difficile, 22 strains; Clostridium perfringens, 10 strains, Propionibacterium spp., nine strains; and anaerobic cocci, 13 strains. RESULTS: Ninety per cent of strains belonging to the B. fragilis group, fusobacteria, propionibacteria and peptostreptococci were inhibited by 4 mg/L CA(1--7)M(2--9)NH2, and the antimicrobial activity was approximately in the same range as that of chloramphenicol. CONCLUSION: This investigation showed that the antimicrobial spectrum of this cecropin---melittin hybrid also includes anaerobic organisms.
Clinical Microbiology and Infection 05/1998; 4(4):181-185. · 4.54 Impact Factor
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ABSTRACT: Bacteroides fragilis is one of the organisms known to produce carbapenem-hydrolysing metallo-β-lactamase, which can confer resistance to a wide variety of β-lactams. The purpose of this study was to identify carbapenem-hydrolysing metallo-β-lactamase-producing B. fragilis strains by means of PCR assay, nucleotide sequencing and enzyme inhibition studies. Ten β-lactam-resistant B. fragilis isolates were investigated. Four imipenem-resistant strains among the 10 isolates gave positive reactions in the PCR assay. The nucleotide sequences of the PCR products from two imipenem-resistant strains shared >98% similarity with the metallo-β-lactamase gene from B. fragilis TAL 3636, which was used as a control. The amino acid sequence homology between the two imipenem-resistant strains and B. fragilis TAL 3636 was 99.2%. These strains produced high amounts of Zn2+-dependent β-lactamases which were inactivated by EDTA.
Anaerobe 5:431-434. · 2.41 Impact Factor
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ABSTRACT: In order to investigate the role of efflux pumps in fluoroquinolone resistance, 35 Bacteroides fragilis group isolates with various resistance patterns against ciprofloxacin, levofloxacin, moxifloxacin and clinafloxacin were studied. The gyrA genotypes were known in all isolates studied. The accumulation of ciprofloxacin with and without carbonyl cyanide m -chlorophenylhydrazone (CCCP) was investigated using a silicon oil based fluorometric assay. Seventeen of 25 multiquinolone-resistant strains had significantly increased ciprofloxacin accumulation in the presence of CCCP compared to the corresponding susceptible type strains. Ten of the resistant isolates with increased efflux had no target mutations at positions 82 or 86 of their GyrA subunits. Strains with highly enhanced efflux were consequently shown to have a significant decrease of quinolone MIC values in the presence of efflux pump inhibitor. The results of the present study propose that high levels of resistance to older as well as newer fluoroquinolones, could be explained by increased activity of efflux pumps in B. fragilis group strains.
Anaerobe 8(5):277-282. · 2.41 Impact Factor
