Mycoplasma pneumonia, treatment

Although erythromycin is a well-established antibiotic, there are relatively few primary indications for its use. These indications include the treatment of Mycoplasma pneumoniae infections, eradication of Corynebacterium diphtheriae from pharyngeal carriers, the early preparox-ysmal stage of pertussis, chlamydial infections, and more recently, the treatment of Legionnaires disease, Campylobacter enteritis, and chlamydial conjunctivitis, and the prevention of secondary pneumonia in neonates. 

A combination of trimethoprim-sulfamethoxazole is effective treatment for a wide variety of infections including P jiroveci pneumonia, shigellosis, systemic salmonella infections, urinary tract infections, prostatitis, and some nontuberculous mycobacterial infections. It is active against most Staphylococcus aureus strains, both methicillin-susceptible and methicillin-resistant, and against respiratory tract pathogens such as the pneumococcus, Haemophilus sp, Moraxella catarrhalis, and Klebsiella pneumoniae (but not Mycoplasma pneumoniae). However, the increasing prevalence of strains of E coli (up to 30% or more) and pneumococci that are resistant to trimethoprim-sulfamethoxazole must be considered before using this combination for empirical therapy of upper urinary tract infections or pneumonia. 

So-called atypical bacteria such as Chlamydia pneumoniae and Mycoplasma pneumoniae are the next most important group of community-acquired pneumonia pathogens, accounting for around one case in every eight in hospitalised patients. Atypical bacteria are not sensitive to beta-lactam antibiotics such as penicillins and cephalosporins and the treatment of choice is a macrolide such as erythromycin. 

Although the clinical usefulness of tetracyclines is limited for most of the common microbial pathogens, they remain drugs of choice (or very effective alternative therapy) for a wide variety of infections caused by less common pathogens. These include brucellosis rickettsial infections such as Rocky Mountain spotted fever, typhus, and Q fever Mycoplasma pneumonia cholera plague Ureaplasma urethritis Chlamydia infections and Lyme disease. Oral doxycycline, 100 mg orally twice a day for 7 days, is a recommended treatment for chlamydial sexually transmitted disease. 

Clarithromycin is indicated for the treatment of mild to moderate upper and lower respiratory tract infections as well as skin infections caused by susceptible strains of Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, H. influenzae, Legionella pneumophila, and Mycoplasma pneumoniae. The usual dosage is 250 to 500 mg twice a day for 7 to 14 days. 

Atypical cases of pneumonia may be caused by Mycoplasma pneumoniae which may be epidemic, or more rarely Chlamydia pneumoniae or psittaci (psittacosis/ornithosis) Legionella pneumophilia or Coxiella burnetii (Q fever) and a tetracycline or erythromycin/ clarithromycin should be given by mouth. Treatment of ornithosis should continue for 10 days after the fever has settled and in mycoplasma pneumonia and Q fever a total of 3 weeks treatment may be needed to prevent relapse. 

A 38-year-old woman took norfloxacin (300 mg/day) and tiaramide hydrochloride (300 mg tds) for an infection with Mycoplasma pneumoniae. One day after the start of treatment, her symptoms of cough and fever worsened and she developed lumbago and hematuria. The diagnosis was confirmed by percutaneous renal biopsy. She slowly improved without specific treatment. Lymphocyte stimulation tests were negative, but rechallenge with norfloxacin was followed by bilateral lumbago. 

The macrolide antibiotics include erythromycin, clarithromycin, azithromycin, tylosin, tilmicosin and tiamulin. Clindamycin and lincomycin are related lincosamides. Susceptible bacteria include staphylococci, streptococci, Campylobacter jejunii, Clostridium spp., R. equi, Mycoplasma pneumoniae and Chlamydia spp. Drugs in this group are only effective against a few Gram-negative bacteria in cattle, namely some strains of Pasteurella and Haemophilus spp. Macrolides and lincosamides are associated with causing colitis in horses, so their use is usually restricted to p.o. erythromycin for the treatment of R. equi infections in foals. Subantimicrobial doses of erythromycin are administered i.v. to horses for gastrointestinal prokinetic action. 

Primary uses Tetracyclines are drugs of first choice in the treatment of infections caused by Mycoplasma pneumoniae (in adults), chlamydia, rickettsia, and vibrios. 

C. Clinical Uses Erythromycin is effective in the treatment of infections caused by Mycoplasma pneumoniae, corynebacterium. Chlamydia trachomatis, Legionella pneumophila, Ureaplasma urealyticum, and Bordetella pertussis. The drug is also active against gram-positive cocci, including pneumococci and beta-lactamase-producing staphylococci (but not MRSA strains). 

In chronic brucellosis, Brucella abortus infects macrophages, thus eluding the immune response [253]. When immunostimulatory drugs such as couma-rin were administered, the symptoms of chronic brucellosis disappeared. These results have encouraged the use of coumarin in other chronic infections such as mononucleosis (Epstein-Barr virus), mycoplasmosis (Mycoplasma pneumoniae), toxoplasmosis (Toxoplasma gondii), and Q fever (Coxiella burnetii). Also, another antiplasmodial coumarin derivate called 5,7-dimethoxy-8-(3 -hydroxy-3 methyl-l -butene)-coumarin has been isolated from the roots of the plant Toddalia asiatica. This finding supports the traditional use of this plant for the treatment of malaria [254]. 

It is indicated in the treatment of lower respiratory tract infection e.g. bronchitis and pneumonia, upper respiratory tract infections e.g. pharyngitis and sinusitis, infections due to chlamydia, legionella and mycoplasma, skin and soft tissue infections and eradication of H. pylori with acid suppressants. 

Levofloxacin, gatifloxacin, gemifloxacin, and moxifloxacin, so-called respiratory fluoroquinolones, with their enhanced gram-positive activity and activity against atypical pneumonia agents (eg, chlamydia, mycoplasma, and legionella), are effective and used increasingly for treatment of upper and lower respiratory tract infections. 

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