Erythromycin bacterial infections

Various other antibacterials -micin or -mycin+ Streptomycin, gentamicin, erythromycin Bacterial infections (33)... 

Q12 Antibiotics are needed by patients with chronic bronchitis as soon as signs of a bacterial infection are present. Chandra has become very breathless at rest, is producing green sputum and has a raised temperature these are all signs that substantial infection is present. Amoxicillin or erythromycin are usually considered suitable first-line antibiotics for these patients. If the infection is thought to be caused by a viral agent, antibiotics would not be used. 

D. Treatment of bacterial infections Antibiotics that selectively affect bacterial function and have minimal side effects in humans are usually selected to treat bacterial infections. Rifampicin, which inhibits the initiation of prokaryotic RNA synthesis, is used to treat tuberculosis. Streptomycin, tetracycline, chloramphenicol, and erythromycin inhibit protein synthesis on prokaiyotic ribosomes and are used for many infections. Chloramphenicol affects mitochondrial ribosomes and must be used with caution. 

Bacterial infection of the skin and subcutaneous tissue can lead to rapidly spreading inflammation known as cellulitis, which requires systemic antibacterial treatment. Treatment is usually with benzylpenicillin and flucloxacillin or erythromycin. 

Outbreaks of bacterial infections in pork processing factories have shown that cuts on the skin made with bone were the most common port of entry of infection (Barnham and Kerby 1981). Streptococcus pyogenes and Staphylococcus aureus were the causative organisms. Nail-biting was suspected as one important cause of transmission of Staphylococcus aureus. Erythromycin-resistant Streptococcus pyogenes affected 46 of 194 workers in an outbreak that lasted 7 months (Sims and Riordan 1996). 

Clarithromycin is better absorbed and irritates the gastrointestinal tract less than erythromycin. It is presumed that its activity exceeds that of erythromycin by 2-4 times with respect to a number of streptococci and staphylococci, and to a few other microorganisms. It is used for treating bacterial bronchitis, pneumonia, skin and sexual infections. It is believed that clarithromycin is the most active macrolide for treating atypical mycobacteria. Synonyms of this drug are biaxin and others. 

Er hromycin Sulfisoxazole (Eryzole, Pediazole) [Anti-infective, Macrolide/Sulfonamide] Uses Upper lower resp tract bacterial Infxns H. influenzae otitis media in children Infxns in PCN-allergic pts Action Macrolide antibiotic w/ sulfonamide Dose Adults. Based on erythromycin content 400 mg erythromycin/1200 mg sulfisoxazole PO q6h Feds > 2 mo. 40-50 mg/kg/d erythromycin 150 mg/kg/d sulfisoxazole PO -s- q6h max 2 g/d erythromycin or 6 g/d sulfisoxazole x 10 d in renal impair Caution [C (D if near term), +] w/ PO anticoagulants, hypoglycemics, phenytoin, cyclosporine Contra Infants <2 mo Disp Susp SE GI upset Additional Interactions T Effects of sulfonamides W/ ASA, diuretics, NSAIDs, probenecid EMS See Erythromycin OD See Erythromycin... 

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. 

A combination of neomycin and nonabsorbable erythromycin base given orally prior to colorectal surgery can markedly reduce the incidence of postoperative wound infection. Orally administered neomycin is sometimes used to suppress the facultative flora of the gut in patients with hepatic encephalopathy. It is unclear how this improves coma, but one theory is that it reduces systemic absorption of the bacterial metabo-htes that allegedly cause hepatic encephalopathy. Although more than 95% of an oral dose of neomycin is excreted unchanged in the stool of normal subjects, the bioavaUabUity of neomycin may be much higher in patients with an abnormal gastrointestinal mucosa. 

Several antibiotics have been used to treat intestinal protozoal infections. Erythromycin and tetracycline do not have a direct effect on the protozoa they act by altering intestinal bacterial flora and preventing secondary infection. Tetracycline also reduces the normal gastrointestinal bacterial flora on which the amebas depend for growth. 

Erythromycin Prevents bacterial protein synthesis by binding to the 50S ribosomal subunit Bacteriostatic activity against susceptible bacteria Community-acquired pneumonia t pertussis corynebacterial, and chlamydial infections Oral, IV hepatic clearance (half-life 1.5 h) dosed every 6 h cytochrome P450 inhibitor Toxicity Gastrointestinal upset, hepatotoxicity, QTC prolongation... 

Campylobacter species are most commonly responsible for outbreaks of bacterial gastroenteritis in developed countries. The majority of die gastrointestinal Campylobacter infections do not require antibiotic treatment and are selflimiting. Where treatment is required, erythromycin is usually recommended. However, fluoroquinolones are often also used pending laboratory results, because they can cover additional bacterial pathogens and are better tolerated than erythromycin. 

Chloramphenicol. Chloramphenicol (Chloromycetin) is a synthetically produced agent that exerts antibacterial effects similar to those of erythromycin that is, it binds to the 50S subunit of bacterial ribosomes and inhibits peptide bond formation. Chloramphenicol is a broad-spectrum antibiotic that is active against many gram-negative and gram-positive bacteria. This drug is administered systemically to treat serious infections such as typhoid fever, Haemophilus infections such as osteomyelitis, rickettsial infections such as Rocky Mountain spotted fever, and certain forms of meningitis. Chloramphenicol may also be administered topically to treat various skin, eye, and ear infections. 

Cethromycin (ABT-773) 39 (Advanced Life Sciences) had an NDA filed in October 2008 for the treatment of CAP.67 Advanced Life Sciences is also evaluating cethromycin 39 against other respiratory tract infections and in pre-clinical studies as a prophylactic treatment of anthrax post-exposure. Cethromycin 3968 70 is a semi-synthetic ketolide derivative of erythromycin 4071 originally synthesised by Abbott Laboratories,72 which like erythromycin 40, inhibits bacterial protein synthesis through binding to the peptidyl-transferase site of the bacterial 50S ribosomal subunit. Important macrolide antibiotics in clinical use today include erythromycin 40 itself, clarithromycin, azithromycin and, most recently, telithromycin (launched in 2001). 

Antimicrobials are over prescribed for exacerbations of asthma. Respiratory tract infections do cause increased airflow obstruction and hyperresponsiveness, but viral rather than bacterial pathogens are the commonest culprits. Antimicrobials should be prescribed only if there is high suspicion of a bacterial respiratory tract infection, e.g. purulent sputum. Note that macrolide antibiotics, such as erythromycin and clarithromycin, interfere with theophylline metabolism. 

Bacterial peliosis hepatis has been determined in cases of HIV infection and cat-scratch fever, where it is caused by Rochahmaea quintana bacteria (Bartonella henselae), (s. p. 482) It presents as a proliferation of blood-filled cystic sinusoidal cavities, which are surrounded by fibromyxoid stroma (M.J. Dolan et at, 1993). Sometimes it is possible to identify the causative organism using PCR or staining with a silver dye (War-thin-Starry). Treatment can then follow with antibiotic agents, such as erythromycin, doxycyclin or clarithromycin. 

To prevent the rapid development of bacterial resistance. Erythromycin and rifampin are used in combination in the treatment of foals with Rhodococcus (R.) equi infections. Each drug has a completely different mechanism of antimicrobial action their combination reduces the chance of chromosomal mutations conferring bacterial resistance. 

Erythromycin is indicated for the treatment of infections caused by erythromycin susceptible bacteria. The drug binds to the 50 S ribosomal subunit inhibiting bacterial RNA-dependent protein synthesis. Susceptible bacteria include most Gram-positive bacteria and the atypical pathogens. 

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