Cleocin
In vitro and in vivo evaluation of antibiotic diffusion from antibiotic-impregnated polymethylmethacrylate beads.

Adams K, Couch L, Cierny G, Calhoun J, Mader JT.

Marine Biotechnical Institute, Department of Internal Medicine, University of Texas Medical Branch, Galveston 77550-2772.

The elution of antibiotics from antibiotic-impregnated polymethylmethacrylate (PMMA) beads was measured in mongrel dogs. The antibiotics, used in mixture with Simplex cement, included cefazolin (Ancef; 4.5 g/40 g cement powder), ciprofloxacin (Cipro; 6 g/40 g powder), clindamycin (Cleocin; 6 g/40 g powder), ticarcillin (Ticar; 12 g/40 g powder), tobramycin (Nebcin; 9.8 g/40 g powder), and vancomycin (Vancocin; 4 g/40 g powder). After a pneumatic drill was used to dredge a trough in the tibia, five beads were implanted. During the next 28 days, seroma samples and serum samples were taken for antibiotic measurements. On Day 28, the dogs were killed, beads removed, and the seroma, serum, bone, and granulation tissue sampled. The results of the study showed that clindamycin, vancomycin, and tobramycin exhibited good elution characteristics and had consistently high levels in bone and granulation tissue.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1563160&dopt=Abstract clindamycin antibiotic Cleocin-T



Cleocin
Salvage therapy with clindamycin/primaquine for Pneumocystis carinii pneumonia.

Noskin GA, Murphy RL, Black JR, Phair JP.

Department of Medicine, Northwestern University Medical School, Chicago, Illinois 60611.

Clindamycin/primaquine is effective for treating mild-to-moderate cases of Pneumocystis carinii pneumonia (PCP) in patients with AIDS. We retrospectively reviewed our experience with this combination among patients in whom conventional therapy had failed or was not tolerated. Twenty-six patients who experienced 28 episodes of PCP received salvage therapy with clindamycin/primaquine at two university-affiliated medical centers. Clindamycin was administered intravenously, (usually 900 mg every 8 hours), after which oral therapy was instituted. Primaquine (30 mg) was given orally to all patients except three; two of these patients received 15 mg of the drug daily and another 30 mg of drug on alternate days. In 11 of the episodes, the patients received clindamycin/primaquine as initial therapy for PCP because of previous intolerance of conventional therapy. In 13 of the episodes, conventional therapy had failed or the patients were unable to tolerate the regimen, while in four episodes conventional therapy failed and the patients were unable to tolerate their therapeutic regimens. Twenty-four (86%; 95% confidence interval, 73%-99%) of 28 episodes were successfully treated with clindamycin/primaquine. The most common adverse effect was the development of an erythematous rash. Clindamycin/primaquine appears to be an attractive alternative for patients in whom standard therapy for PCP has failed or cannot be tolerated.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1571426&dopt=Abstract clindamycin antibiotic Cleocin-T



Cleocin
[The effect of clindamycin on intraphagocytic Staphylococcus aureus in leukocytes from patients with chronic osteomyelitis]

[Article in Spanish]

Burgaleta C, Velasco GL, Peletier R, Messeguer M, Pernas M.

Servicios de Hematologia y Traumatologia, Hospital Ramon y Cajal, Madrid.

BACKGROUND: Osteomyelitis are infections difficult to be completely cured, and its optimal therapy had not clearly been established. METHODS: We study the bactericidal activity of polymorphonuclear leukocytes and also of serum from 13 patients with Staphylococcus aureus chronic osteomyelitis. We also studied the activity of clindamycin against intraphagocytic S. aureus. The study was done in vitro using control S. aureus strain ATCC 25923 and also microorganisms recovered from infected bone. RESULTS: S. aureus two hours survival rates in polymorphonuclear leukocytes were 13.5 +/- 4.4 x 10(6), 10.5 +/- 4.0 x 10(6), 11.0 +/- 4.0 x 10(6), using polymorphonuclear leukocytes from controls and patients, with control and autologous sera respectively (p greater than 0.05). We have observed a bactericidal activity defect in polymorphonuclear leukocytes from one patient and in the sera of 7 other patients. The incubation with clindamycin (10 MIC) reduces the number of cfu/ml to 2.1 +/- 0.9 x 10(6), 1.1 +/- 0.7 x 10(6) y 1.9 +/- 1.1 x 10(6), and we also detected and additional inhibition of 81.7 +/- 7%, 70.7 +/- 17% and 79.0 +/- 4% respectively. CONCLUSION: The results of our study confirm that clindamycin has an intracellular action against intraphagocytic S. aureus and also showed the ability of this antimicrobial agent to cover defects in defensive mechanism of the host. Both statements give support the potential usefulness of clindamycin as therapy for bone infections due to S. aureus.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1576187&dopt=Abstract clindamycin antibiotic Cleocin-T



Cleocin
Inducible expression of ribosomal clindamycin resistance in Bacteroides vulgatus.

Reig M, Fernandez MC, Ballesta JP, Baquero F.

Servicio de Microbiologia, Hospital Ramon y Cajal, Instituto Nacional de la Salud, Madrid, Spain.

The abilities of erythromycin and clindamycin to act as inducers of clindamycin resistance in the strain Bacteroides vulgatus RYC18F6 is evaluated in vivo (efficiency of plating of inhibitory clindamycin concentrations) and in vitro [efficiency of poly(U)-directed polypeptide synthesis by ribosomes]. Uninduced cells failed to grow during the first 72 h, even at a very low clindamycin concentration (0.1 microgram/ml); after induction with erythromycin or clindamycin, cells were able to form colonies at 32 micrograms/ml after 48 h. The in vitro polymerization test with B. vulgatus RYC18F6 ribosomes (S-30 extract) showed that ribosomes from uninduced cells were fully sensitive to the inhibitory effect of clindamycin. Ribosomes obtained from erythromycin- or clindamycin-induced cells presented a reduced sensitivity to clindamycin inhibition. These results show that resistance to clindamycin in B. vulgatus RYC18F6 is an inducible phenomenon involving a ribosomal modification, probably similar to that previously described for gram-positive bacteria.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1622176&dopt=Abstract clindamycin antibiotic Cleocin-T



Cleocin
End-plate ion channel block produced by lincosamide antibiotics and their chemical analogs.

Prior C, Fiekers JF, Henderson F, Dempster J, Marshall IG, Parsons RL.

Department of Physiology and Pharmacology, University of Strathclyde, Glasgow, Scotland.

Five lincosamide compounds were studied for their effects on end-plate currents (epcs), miniature end-plate currents and acetylcholine-induced current fluctuations in the garter snake costocutaneous nerve-muscle preparation. At high concentrations, lincomycin and clindamycin reduced epc amplitude, but analysis of driving functions showed that only with clindamycin was this due solely to changes in epc quantal content. The effect of lincomycin on epc amplitude was exaggerated by rapid channel block during the rising phase of the epc. Clindamycin produced currents with a single exponential decay and single Lorentzian noise spectra. All the other compounds produced currents which decayed as the sum of two exponential components. For lincomycin and epilincomycin, noise spectra consisted of two Lorentzian components. For epiclindamycin and deoxylincomycin, although epcs and miniature end-plate currents decayed with two components, it was not possible to separate two components in the noise spectra. A kinetic analysis of ion channel blocking actions showed only small differences between the two pairs of stereoisomers studied. End-plate ion channel blocking and unblocking rate constants did not vary greatly among the compounds but the end-plate ion channel unblocking rate constant values for the two lincomycin stereoisomers were larger than those for the two clindamycin stereoisomers. Deoxylincomycin exhibited properties similar to those of the clindamycins. It was concluded that lipid solubility, not stereochemical conformation, plays the greater role in determining the ion channel blocking properties within the series, particularly that of the rate of dissociation of the compound from end-plate ion channels.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1702153&dopt=Abstract clindamycin antibiotic Cleocin-T



Cleocin
Comparison of the bactericidal activity of clindamycin and metronidazole against cefoxitin-susceptible and cefoxitin-resistant isolates of the Bacteroides fragilis group.

Stratton CW, Weeks LS, Aldridge KE.

Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee.

Time-kill kinetic methodology was used to evaluate the bactericidal activity of cefoxitin, cefotetan, clindamycin, and metronidizole against cefoxitin-susceptible and cefoxitin-resistant isolates of the Bacteroides fragilis group. Overall, metronidazole was the most bactericidal agent, with all isolates being killed with less than or equal to 4 micrograms/ml at 24 hr. Clindamycin was the next most bactericidal agent, with 20 of 26 isolates being killed with less than 16 micrograms/ml. Six isolates with clindamycin MICs greater than or equal to 64 micrograms/ml were not killed at 24 hr, with concentrations as high as 256 micrograms/ml. Cefoxitin and cefotetan were the least bactericidal agents tested. Seven isolates with MICs of greater than or equal to 64 micrograms/ml to each agent demonstrated a lack of killing at 24 hr, with concentrations of the respective agent as high as 256 micrograms/ml. At concentrations with either agent of 32 micrograms/ml, the remaining 19 isolates were killed at 24 hr. Of the six B. fragilis isolates resistant to clindamycin, four were also resistant to both cefoxitin and cefotetan. We conclude that in hospitals with cefoxitin-resistant B. fragilis group isolates, metronidazole would provide appropriate therapy.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1797454&dopt=Abstract clindamycin antibiotic Cleocin-T