Cleocin
Potentiation of phagocytosis of Bacteroides fragilis following incubation with clindamycin.

Howard RJ, Soucy DM.

We studied the effect of clindamycin on phagocytosis of Bacteroides fragilis (MIC = 0.05 mg/l). In the in-vitro test system phagocytosis of Bact. fragilis was less than 11% for the first 30 min of incubation. At 60 min, 25-50% of Bact. fragilis were phagocytosed. At 90 min, phagocytosis increased to 60% of the bacterial inoculum and did not increase thereafter. When clindamycin (0.02 mg/l) was incubated with neutrophils for 2 h prior to exposure to bacteria, there was no increase in phagocytosis. When clindamycin (0.02 mg/l) was incubated with bacteria for 2 h before exposure to neutrophils, phagocytosis increased to 23.1 +/- 5.9 (S.D.) per cent at 30 min compared to 1.1 +/- 15.1% (P less than 0.05) for bacteria not exposed to clindamycin. There was no difference in phagocytosis between the two groups at 60 and 90 min. One-fifth the MIC (0.01 mg/l) but not 0.004 mg/l also led to increased phagocytosis at 30 min but not at 60 min if previously incubated with clindamycin. Thus, clindamycin potentiates phagocytosis of Bact. fragilis. It can act directly on bacteria and promote phagocytosis, although the clinical importance of this last mode of action is not currently known.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6643342&dopt=Abstract clindamycin antibiotic Cleocin-T



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In vitro activity of U-57930E against anaerobic bacteria and its comparison with clindamycin, ampicillin, carbenicillin and tetracycline.

Qadri SM, Karim MR, Flournoy DJ.

The in vitro activity of U-57930E, a pipecolic acid amide of clindamycin, was compared with those of clindamycin, ampicillin, carbenicillin and tetracycline against 321 anaerobic clinical isolates. The MIC (micrograms/ml) of U-57930E that inhibited 95% Bacteroides fragilis, Peptococcus prevotii, B. melaninogenicus and P. asaccharolyticus was 0.0625; 0.03125 for Peptostreptococcus anaerobius, B. vulgatus, Propionibacterium and Peptococcus species. Clindamycin, on the other hand, gave MIC values of 0.5 microgram/ml for B. fragilis, P. prevotii and P. asaccharolyticus, 0.25 for Propionibacterium sp. All strains of Clostridium perfringens were inhibited by 0.5 microgram/ml of U-57930E. Both clindamycin and U-57930E showed similar MIC values for all strains of Fusobacterium nucleatum and Propionibacterium acnes tested. The MIC values for ampicillin, carbenicillin and tetracycline were within the expected range. U-57930E had a 4 approximately 8 fold lower MIC than clindamycin and is significantly active against anaerobic bacteria.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6678915&dopt=Abstract clindamycin antibiotic Cleocin-T



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Penetration of clindamycin into experimental Staphylococcus aureus infections.

Simon GL, Miller HG, Camas JM, Geelhoed GW.

Inactivation of clindamycin at the site of experimental infection with Staphylococcus aureus was studied using rabbits with plastic capsules implanted in the peritoneal cavity. The mean percentage penetration of bioactive clindamycin (concentration in capsule divided by simultaneous concentration in serum times 100) into infected and noninfected capsules was 30.4 per cent and 13.0 per cent, respectively. In contrast, the mean penetration of radiolabeled clindamycin into infected capsules was 38.4 per cent. These findings indicate that the observed loss of bioactivity in infected capsules is due to intracapsular inactivation of clindamycin and not to an alteration in capsular permeability. Biologic inactivation of clindamycin was not evident after in vitro incubation of the drug with Staphylococcus aureus. These results suggest that the observed loss of bioactivity may be due to chemical modification by enzymes in the inflammatory exudate or to binding of the antibiotic to tissue components.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6710298&dopt=Abstract clindamycin antibiotic Cleocin-T



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Genetic analysis of clindamycin resistance in Bacteroides species.

Guiney DG Jr, Hasegawa P, Stalker D, Davis CE.

The genetic basis of clindamycin and tetracycline resistance in species of Bacteroides was studied in 13 resistant clinical isolates; 10 isolates were resistant to high levels of clindamycin (greater than 160 micrograms/ml) and three were resistant to low levels of clindamycin (5-20 micrograms/ml). All of the isolates were resistant to tetracycline. None of the strains with low-level clindamycin resistance could transfer resistance to either antibiotic. Three isolates resistant to high levels of clindamycin transferred tetracycline resistance to a sensitive Bacteroides fragilis recipient, and one of these (strain 1126) also transferred high-level clindamycin resistance. None of the transfer-proficient strains of Bacteroides contained plasmid DNA. However, DNA homology was detected by hybridization between the clindamycin resistance plasmid pBF4 isolated in France and sequences in our high-level clindamycin-resistant strains from California. A common homologous 4.8 megadalton EcoR1 fragment was identified in the whole cell DNA of the transfer-proficient strain 1126 of B. fragilis and two other species of the B. fragilis group.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6833799&dopt=Abstract clindamycin antibiotic Cleocin-T



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Clindamycin in the treatment of toxoplasmic retinochoroiditis.

Lakhanpal V, Schocket SS, Nirankari VS.

We treated 26 patients with acute toxoplasmic retinochoroiditis with clindamycin between 1974 and 1982. Four patients were treated with clindamycin alone and 17 with clindamycin and prednisolone. Five patients received clindamycin and prednisolone, sulfadiazine, pyrimethamine, or cryocoagulation, or a combination of these. All patients with the acute disease had the characteristic foci and a positive titer on the Sabin-Feldman dye test of at least 1:16. Other causes of retinochoroiditis were excluded. All but two patients, who developed diarrhea after two weeks, received clindamycin for a minimum of three weeks. All patients improved after two weeks of treatment, but two patients with lesions larger than 2 disk diameters required an additional six weeks of treatment to heal completely. During follow-up periods ranging from 18 months to seven years (mean, three years) there have been only two recurrences (7.7%). Complications with clindamycin treatment were limited to gastrointestinal upsets, diarrhea, and skin rash. There were no cases of pseudomembranous colitis, the most serious reported complication of clindamycin use.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6846454&dopt=Abstract clindamycin antibiotic Cleocin-T



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Penicillin failure in the treatment of Bacteroides fragilis lung abscess. Experimental study in rabbits.

Thadepalli H, Kannangara DW, Bach VT.

Carbenicillin, chloramphenicol, doxycycline, and clindamycin were compared with penicillin for the treatment of lung abscess in an animal model produced by transtracheal inoculation of a mixture of anaerobes: Bacteroides fragilis, Peptococcus morbillorum, Eubacterium lentum and Fusobacterium nucleatum. Both chloramphenicol and doxycycline eliminated the bacteria but failed to close the abscess cavity. Carbenicillin, although it eradicated B. fragilis, failed to close the abscess cavity in 3 of 6 animals. In all animals tested, clindamycin sterilized the abscess cavities and healed the lung abscesses, while penicillin failed to eradicate the infection. Clindamycin was significantly more effective than penicillin in the elimination of anaerobic bacteria from the lung (p less than 0.05). Clindamycin also closed the abscess cavity faster than penicillin (p less than or equal to 0.02). The superior efficacy of clindamycin may have been the result of accumulation in the lung tissue in concentrations four- to eightfold higher than in the serum.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6872619&dopt=Abstract clindamycin antibiotic Cleocin-T