Showing papers by "Itzhak Brook published in 1991"
TL;DR: It is illustrated that although Propionibacterium species are rarely associated with infections, these organisms can occasionally cause serious infections.
Abstract: Eight hundred and sixteen isolates of Propionibacterium species (725 of which were Propionibacterium acnes) were isolated from 3,971 specimens submitted for the identification of anaerobic bacteria over the course of 10 years. A total of 94 Propionibacterium isolates (12%) identified in 92 patients were considered to cause infection. The rest of the isolates were determined to be contaminants or of uncertain pathogenic significance. Significant infections caused by Propionibacterium species were associated with the blood in 15 patients, central nervous system in 11, lymph glands in 10, abscesses in eight, joints in seven, wounds in seven, cysts in six, and sinuses in five. Predisposing or underlying conditions were noted in 66 patients (70%). The most common conditions were the presence of foreign bodies (29 patients), diabetes (12), previous surgery (10), trauma (seven), malignancy (seven), immunodeficiency (seven), and steroid therapy (four). Antimicrobial therapy was administered to 83 patients; for 47 patients this therapy was given in conjunction with surgical drainage or correction. Surgical drainage alone was performed in nine patients. Five patients (5%) died. These data illustrate that although Propionibacterium species are rarely associated with infections, these organisms can occasionally cause serious infections.
201 citations
TL;DR: This study highlights the polymicrobial nature and importance of anaerobic bacteria in periapical abscesses and identifies three predominant isolates: Bacteroides spp, Streptococcus spp.
Abstract: Aspirates of pus from periapical abscesses in 39 patients were studied for aerobic and anaerobic bacteria. Bacterial growth was present in 32 specimens. A total of 78 bacterial isolates (55 anaerobic and 23 aerobic and facultative) were recovered, accounting for 2.4 isolates per specimen (1.7 anaerobic and 0.7 aerobic and facultatives). Anaerobic bacteria only were present in 16 (50%) patients, aerobic and facultatives in 2 (6%), and mixed aerobic and anaerobic flora in 14 (44%). The predominant isolates were Bacteroides spp. (23 isolates, including 13 Bacteroides melaninogenicus group), Streptococcus spp. (20), anaerobic cocci (18), and Fusobacterium spp. (9). Beta-lactamase-producing organisms were recovered from 7 of the 21 (33%) specimens that were tested. This study highlights the polymicrobial nature and importance of anaerobic bacteria in periapical abscess.
164 citations
TL;DR: The polymicrobial nature and importance of anaerobic bacteria in acute suppurative parotitis is highlighted, as well as the importance of beta-Lactamase-producing organisms, which are cytotoxic to aerobic and facultative bacteria.
Abstract: Aspirates of pus from acute suppurative parotitis were studied for aerobic and anaerobic bacteria. Bacterial growth was present in 23 specimens. A total of 36 bacterial isolates (20 anaerobic and 16 aerobic and facultative) were recovered, accounting for 1.6 isolates per specimen (0.9 anaerobic and 0.7 aerobic and facultative). Anaerobic bacteria only were present in 10 (43%) patients, aerobic and facultatives in 10 (43%), and mixed aerobic and anaerobic flora in 3 (13%). Single bacterial isolates were recovered in 9 infections, 6 of which were Staphylococcus aureus and 3 were anaerobic bacteria. The predominant bacterial isolates were S. aureus (8 isolates), Bacteroides sp. (6 isolates, including 4 Bacteroides melaninogenicus group), and Peptostreptococcus sp. (5). beta-Lactamase-producing organisms were recovered from 11 (73%) of the 15 specimens tested. This study highlights the polymicrobial nature and importance of anaerobic bacteria in acute suppurative parotitis.
61 citations
33 citations
TL;DR: The polymicrobial etiology of decubitus ulcers in hospitalized children and the association of bacterial flora with the anatomical site of the ulcer are demonstrated.
32 citations
TL;DR: In vivo elimination of encapsulated organisms of the B. fragilis group was found to be more difficult than elimination of unencapsulated isolates, illustrating the complexity and difficulties encountered when in vitro activity is correlated with in vivo efficacy.
Abstract: In vitro susceptibility testing is only one step in the evaluation of the potential efficacy of antimicrobial agents against the Bacteroides fragilis group. An assessment of in vivo efficacy, with a consideration of the factors that can best be studied in an infected host, is also an integral part of this process. Abscess models in rodents have been used to correlate in vitro activity with in vivo efficacy against this group of microorganisms. For metronidazole, clindamycin, moxalactam, and cefoxitin, the correlation was strong; for chloramphenicol and carbenicillin, it was not. In vivo studies of mixed infection with the B. fragilis group and Escherichia coli showed that cefoxitin and imipenem were effective; in contrast, cefotetan was not effective against resistant strains. Only strains susceptible to ceftizoxime in the agar dilution test were also affected by this drug in vivo. The so-called inoculum effect noted with ceftizoxime may explain this finding. In vivo elimination of encapsulated organisms of the B. fragilis group was found to be more difficult than elimination of unencapsulated isolates. The beta-lactamase produced by Bacteroides species can protect the enzyme-producing organism as well as its partners in mixed infections from the effects of beta-lactam antibiotics. These data illustrate the complexity and difficulties encountered when in vitro activity is correlated with in vivo efficacy.
18 citations
2 citations