Anaerobic infections

Cefuroxime (35) is effective against community-acquired pneumonia in which ampicillin-resistant Haemophilus influence is the probable etiologic agent. Cefoxitin (23) is used to treat mixed aerobic—anaerobic infections including pelvic infections, intra-abdorninal infections, and nosocomial aspiration pneumonia. Cefonicid (31), because of its long half-life has been used in a once-a-day regimen to treat a variety of mild to moderate infections including community-acquired pneumonias, urinary tract infections, and infections of the skin and soft tissue (132,215). 

Clindamycin has found use in the treatment of common infections caused by gram-positive cocci It is also efficacious in the treatment of anaerobic infections, including actinomycosis (38). Clindamycin has been shown to be active against strains of P/asmodiumin animals (66—68). 

Licosamides Clindamycin and lincomycin Serious staph-, pneumo-, and streptococcal infections in penicillin-allergic patients, also anaerobic infections... 

Table 5. Parenterally administered antimicrobial agents which can be used alone or combined to provide effective coverage of the mixed aerobic-anaerobic infections arising from human colonic bacteria for patients requiring preventive therapy...

While typical doses of cefazolin are ineffective for anaerobic infections, the recommended 2-g dose produces concentrations high enough to be inhibitory to these organisms. A 24-hour duration has been used in most studies, but single-dose therapy may also be effective. 

Lincosamides (lincomycin and clindamycin) are representatives of a very small group of drugs synthesized up of an amino acid bound to an amino sugar. Lincosamides bind with the 50 S ribosomal subunit of bacteria and inhibit protein synthesis. They also inhibit pep-tidyltransferase action. Lincosamides are bacteriostatic antibiotics however, when they reach a certain level in the plasma, they also exhibit bactericidal action against some bacteria. Lincosamides are highly active against anaerobic infections such as Peptococcus, Peptostreptococcus, Actinomyces, Propionibacterium, and Clostridium fringens, a few types of Peptococcus and Clostridium. 

Lincosamides are most often used for treating anaerobic infections such as intraabdom-inal and female infections. 

In terms of mechanism of action and indications for use, tinidazole is very similar to metronidazole. It is also effective against amebas, trichomonad, lambliosis, acute ulcerative gingivitis, and post-operational anaerobic infections. It is used for treating practically all protozoan infections. Synonyms of this drug are tinaport, tinimed, and tinisan. 

Anaerobic infections Treaimeni of serious infections caused by susceptible anaerobic bacteria. Effective in Bacteroides fragilis infections resistant to clindamycin, chloramphenicol, and penicillin. 

Anaerobic bacterial infections In the treatment of most serious anaerobic infections, metronidazole is usually administered IV initially. 

Clindamycin is a chlorine-substituted derivative of lincomycin. However it is more potent and is better absorbed from the gastrointestinal tract and has therefore replaced lincomycin in most situations. Clindamycin is in principle a bacteriostatic agent. Its indications are mainly limited to mixed anaerobic infections. As mentioned above it has a similar mechanism of action as erythromycin. It selectively inhibits bacterial protein synthesis by binding to the same 50s ribosomal subunits. Erythromycin and clindamycin can interfere with each other by competing for this receptor. Also cross-resistance with erythromycin frequently occurs. Resistance is rather chromosomal rather than plasmid mediated and is especially found in cocci and Clostridium difficile. 

Oral anti-staphylococcal penicillins or cotrimox-azole are effective against most skin pathogens. Five days of therapy (or 3 days after local signs are resolved) is usually sufficient. For arthritis 2 or 3 weeks of therapy are required. In chronic osteomyelitis, resection of dead tissue should be followed by at least six weeks to 3 months of antibiotics until the ESR returns to normal. Oral quinolones are useful for gram-negative osteomyelitis while clindamycin is effective in gram-positive and anaerobic infections. 

Unlabeled Uses Treatment of bacterial vaginosis, grade 111-lV decubitus ulcers with anaerobic infection, Flelicobacler pytori-associated gastritis and duodenal ulcer, inflammatory bowel disease topical treatment of acne rosacea... 

Other indications in which chloramphenicol can be used are H. influenzae meningitis, urinary tract infections, anaerobic infections caused by Bacteroidesfragilis and locally in eye and external ear infections. 

It is used in the treatment of severe anaerobic infections caused by bacteroides and other anaerobes. It is also used in combination with aminoglycoside in the treatment of abdomen and GIT wounds, infections of female genital tract, pelvic abscesses, aspiration pneumonia and septic abortion. It is also used for prophylaxis of endocarditis. It is also used along with primaquine in Pneumocystis carinii pneumonia in AIDS patients and with pyrimethamine for toxoplasmosis. 

It is indicated in giardiasis, amoebic liver abscess, intestinal amoebiasis, trichomoniasis, ulcerative gingivitis, treatment and prophylaxis of anaerobic infections. 

The indications for penidllin-3-lactamase inhibitor combinations are empirical therapy for infections caused by a wide range of potential pathogens in both immunocompromised and immunocompetent patients and treatment of mixed aerobic and anaerobic infections, such as intra-abdominal infections. Doses are the same as those used for the single agents except that the recommended dosage of piperacillin in the piperacillin-tazobactam combination is 3 g every 6 hours. Adjustments for renal insufficiency are made based on the penicillin component. 

Clindamycin is indicated for the treatment of skin and soft-tissue infections caused by streptococci and staphylococci. It is often active against community-acquired strains of methicillin-resistant S aureus, an increasingly common cause of skin and soft tissue infections. Clindamycin is also indicated for treatment of anaerobic infection caused by bacteroides and other anaerobes that often participate in mixed infections. Clindamycin, sometimes in combination with an aminoglycoside or cephalosporin, is used to treat penetrating wounds of the abdomen and the gut infections originating in the female genital tract, eg, septic abortion and pelvic abscesses and aspiration pneumonia. Clindamycin is now recommended rather than erythromycin for prophylaxis of endocarditis in patients with valvular heart disease who are undergoing certain dental procedures. Clindamycin plus primaquine is an effective alternative to trimethoprim-sulfamethoxazole for moderate to moderately severe Pneumocystis jiroveci pneumonia in AIDS patients. It is also used in combination with pyrimethamine for AIDS-related toxoplasmosis of the brain. 

Clindamycin Prevents bacterial protein synthesis by binding to the 50S ribosomal subunit Bacteriostatic activity against susceptible bacteria Skin and soft tissue infections anaerobic infections Oral, IV hepatic clearance (half-life 2.5 h) dosed every 6-8 hours Toxicity Gastrointestinal upset, difficile colitis... 

A structurally similar agent, tinidazole, is a once-daily drug approved for treatment of trichomonas infection, giardiasis, and amebiasis. It also is active against anaerobic bacteria, but is not FDA-approved for treatment of anaerobic infections. 

Lincomycin has found use in the treatment of diseases of the ear, throat, nose, respiratory tissue, skin and soft tissue, bone, joint, dental, and septicemic infections caused by staphylococci, pneumonococci, and streptococci (other than enterococci). It has also been used in the treatment of diphtheria and a variety of anaerobic infections, including actinomycosis. 

Clindamycin is indicated for treatment of severe anaerobic infection caused by bacteroides and other anaerobes that often participate in mixed infections. Clindamycin, sometimes in combination with an aminoglycoside or cephalosporin, is used to treat penetrating wounds of the abdomen and the gut infections originating in the female genital tract, eg, septic abortion and pelvic abscesses or... 

A malodorous wound is consistent with an anaerobic infection requiring suitable anaerobe cover such as metronidazole or clindamycin. 

Tubo-ovarian abscess is usually associated with anaerobic infection. 

Chloramphenicol is used far the treatment of typhoid fever, bacterial meningitis, and certain anaerobic infections such as in the treatment of cystic fibrosis in children. 

Dose. Established anaerobic infection is treated with metronidazole by mouth 400 mg 8-hourly by rectum 1 g 8-hourly for 3 days followed by 1 g 12-hourly or by i.v. infusion 500 mg 8-hourly. A topical gel preparation is useful for reducing the odour associated with anaerobic infection of fungating tumours. 

Hydrocolloids are suitable for desloughing and for light to medium exuding wounds—but are contraindicated if an anaerobic infection is present. They have been used successfully in the treatment of chronic leg ulcers, pressure ulcers, minor burns, granulating wounds, and wounds exhibiting slough or necrotic tissue or wounds with moderate exudate, as well as skin barriers in the management of stoma. 

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