zithromax and Endocarditis--Bacterial

Azithromycin has recently replaced clindamycin oral suspension for prop hylaxis of infective endocarditis (IE) in children. It is also currently recommended by the American Heart Association as an alternative to penicillin, along with clindamycin for prophylaxis of infective endocarditis in adults. The objectives of this paper were to firstly, review the current literature on the efficacy of azithromycin as a suitable prophylactic agent in the prevention of infective endocarditis; and secondly, to review its pharmacological properties as a suitable therapeutic agent in the management of odontogenic infections.. A review of the literature.. The available evidence from animal models on infective endocarditis supports the efficacy of this drug as a prophylactic agent against oral streptococci. The pharmacological properties of this agent would make it a very promising therapeutic adjunct in the management of odontogenic infections. At present there are only a small number of studies available with valuable data on the efficacy of this relatively new drug. Further investigations comparing this compound with other commonly used adjuncts would be of great benefit.

Topics: Adolescent; Adult; Animals; Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Bacterial Infections; Child; Child, Preschool; Dental Care; Dental Care for Chronically Ill; Endocarditis, Bacterial; Humans; Middle Aged; Mouth Diseases; Tooth Diseases

When treating oral infections, clinicians have used the macrolide antibiotic erythromycin as an alternative antibiotic for patients who have documented allergic reactions to penicillins. In this article, the author reports on his assessment of the pharmacology of erythromycin and the newer macrolide antibiotics, as well as of their indications for the prevention of bacterial endocarditis and their possible use for oral-dental infections.. The author reviewed the current clinical pharmacology literature with specific emphasis on reports indicating these antibiotics' efficacy in treating oral-dental infections.. Azithromycin, clarithromycin and dirithromycin are erythromycin analogues that are currently marketed in the United States. All three have the therapeutic advantages over erythromycin of longer durations of action, enhanced acid stabilities and improved tissue distributions. A lower incidence of gastrointestinal distress and abdominal cramping is reported for all three of these newer agents than for erythromycin. Azithromycin and dirithromycin do not appear to compete for the same hepatic drug-metabolizing enzymes as erythromycin and therefore are not associated with the same drug interactions.. The newer macrolide antibiotics offer the advantage of fewer adverse gastrointestinal effects than erythromycin and dosing regimens of only once or twice a day. Yet, the extremely high price of the newer macrolides compared with that of erythromycin limits their routine use.

Topics: Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Clarithromycin; Cytochrome P-450 Enzyme System; Delayed-Action Preparations; Dental Care for Chronically Ill; Drug Costs; Endocarditis, Bacterial; Erythromycin; Focal Infection, Dental; Humans; Liver; Macrolides; Prodrugs; Tissue Distribution

Topics: Aged; Ampicillin; Animals; Aortic Valve; Azithromycin; Bartonella henselae; Cat-Scratch Disease; Cats; Drug Therapy, Combination; Endocarditis, Bacterial; Gentamicins; Heart Valve Prosthesis Implantation; Humans; Male; Mitral Valve; Mitral Valve Prolapse; Ultrasonography

Topics: Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Child; Child, Preschool; Clindamycin; Dental Care for Children; Endocarditis, Bacterial; Humans

Azithromycin and ampicillin protected 94 and 72% of animals challenged with Streptococcus oralis, respectively (P = 0.177), while azithromycin and vancomycin protected 59 and 94% of the methicillin-resistant Staphylococcus aureus (MRSA)-challenged animals, respectively (P = 0.018). Azithromycin is effective in preventing experimental streptococcal endocarditis, but against MRSA it is less effective than vancomycin.

Topics: Administration, Oral; Animals; Anti-Bacterial Agents; Aortic Valve; Azithromycin; Endocarditis, Bacterial; Female; Rabbits; Staphylococcal Infections; Streptococcal Infections

The efficacy of azithromycin or clarithromycin was compared to that of amoxicillin, clindamycin, or erythromycin for the prevention of viridans group streptococcus experimental endocarditis. Rabbits with catheter-induced aortic valve vegetations were given no antibiotics or two doses of amoxicillin at 25 mg/kg of body weight, azithromycin at 10 mg/kg, clarithromycin at 10 mg/kg, clindamycin at 40 mg/kg followed by clindamycin at 20 mg/kg, or erythromycin at 10 mg/kg. Antibiotics were administered 0.5 h before and 5.5 h after intravenous infusion of 5 x 10(5) CFU of Streptococcus milleri. Forty-eight hours after bacterial inoculation, the rabbits were killed and aortic valve vegetations were aseptically removed and cultured for bacteria. Infective endocarditis occurred in 88% of untreated animals, 1% of animals receiving amoxicillin, 9% of animals receiving erythromycin, 0% of animals receiving clindamycin, 2.5% of animals receiving clarithromycin, and 1% of animals receiving azithromycin. All five regimens were more effective (P < 0.001) than no prophylaxis. Erythromycin was less effective (P < 0.05) than amoxicillin or clindamycin. Azithromycin or clarithromycin was as effective as amoxicillin, clindamycin, or erythromycin for the prevention of viridans group streptococcus experimental endocarditis in this model.

Topics: Amoxicillin; Animals; Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Clarithromycin; Clindamycin; Endocarditis, Bacterial; Erythromycin; Rabbits; Streptococcus

Since serious sequelae may follow streptococcal infections, eradication is viewed as necessary for successful therapy. Studies were therefore conducted to compare the effectiveness of azithromycin with other macrolide antibiotics and amoxycillin to eliminate these organisms in experimental localized infections. In a Streptococcus pneumoniae lung infection induced by transtracheal challenge, the pathogen was not recovered after therapy with azithromycin (ED50 7.9 mg/kg), while clarithromycin was not effective (ED50 > 100 mg/kg). However, in a S. pneumoniae middle ear infection, azithromycin and clarithromycin were effective (ED50 2.9 and 6.3 mg/kg, respectively) in eradicating the pathogen from this closed space infection. Against a localized Streptococcus pyogenes infection (implanted inoculated disc), azithromycin effectively eradicated the pathogen, while clarithromycin, roxithromycin and erythromycin did not. Eradication of a viridans streptococcus or Streptococcus gordonii (formerly Streptococcus sanguis) from heart tissue in experimental bacterial endocarditis was also evaluated. Azithromycin given prophylactically or therapeutically was efficacious in eliminating the viridans streptococcus and S. gordonii in the bacterial endocarditis model of infection; erythromycin was only marginally effective in the same studies. All studies provided evidence of the bactericidal action of azithromycin in vivo and demonstrated the ability of the compound to eradicate streptococcal pathogens in localized infections.

Topics: Amoxicillin; Animals; Anti-Bacterial Agents; Azithromycin; Clarithromycin; Disease Models, Animal; Endocarditis, Bacterial; Erythromycin; Female; Gerbillinae; Male; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Otitis Media; Pneumococcal Infections; Pneumonia; Rats; Roxithromycin; Streptococcal Infections; Streptococcus pyogenes