Tuberculosis causes

Florfenicol (2) has been approved in Japan for the treatment of pseudo-tuberculosis caused by Pasteurellapiscicida and streptococcosis m. yeUowtail fish. The recommended dose is 10 mg/kg for up to one week and the drug withdrawal time is five days after cessation of treatment. Florfenicol is active in bovine respiratory disease caused by Pasteurella species and mastitis caused by Staphylococci and Streptococci. It is also effective in neonatal cohbacillosis caused by E. coli. The drug is being developed worldwide by Schering-Plough Animal Health for the treatment of aquatic and bovine diseases. 

Tuberculosis caused by drug-resistant organisms should be considered in patients who have no response to therapy and in patients who have been treated in the past... 

TABLE 72-3. Drug Regimens for Culture-Positive Pulmonary Tuberculosis Caused by Drug-Susceptible Organisms32... 

The long-term (more than several weeks) use of levofloxacin in children and adolescents has not be approved because of concerns about effects on bone and cartilage growth. However, most experts agree that the drug should be considered for children with tuberculosis caused by organisms resistant to both INH and RIF. The optimal dose is not known. 

Tuberculosis has been a major cause of death in humans (and other animals) since the earhest recorded history and certainly before that. Tuberculosis caused the death of about two million people in 2004. It is the leading cause of death in those suffering from AIDS. 

Isoniazid (isonicotinic acid hydrazide, or INH) is the most active drug for the treatment of tuberculosis caused by susceptible strains. It is a synthetic agent with a structural similarity to that of pyridoxine. 

Rifapentine is an analogue of rifampin that is active against M. tuberculosis and M. avium. Rifapentine s mechanism of action, cross-resistance, hepatic induction of P450 enzymes, drug interactions, and toxic profile are similar to those of rifampin. It has been used in the treatment of tuberculosis caused by rifampin-susceptible strains. 

It is used in the treatment of tuberculosis caused by streptomycin resistant strains but since agents with lesser toxicity e.g. capreomycin and amikacin are available, its use is obsolete. 

It is indicated in the treatment of tuberculosis caused by rifampicin susceptible strains. 

Rifampin, usually 600 mg/d (10 mg/kg/d) orally, must be administered with isoniazid or other antituberculous drugs to patients with active tuberculosis to prevent emergence of drug-resistant mycobacteria. In some short-course therapies, 600 mg of rifampin are given twice weekly. Rifampin 600 mg daily or twice weekly for 6 months also is effective in combination with other agents in some atypical mycobacterial infections and in leprosy. Rifampin, 600 mg daily for 4 months as a single drug, is an alternative to isoniazid prophylaxis for patients with latent tuberculosis only, who are unable to take isoniazid or who have had exposure to a case of active tuberculosis caused by an isoniazid-resistant, rifampin-susceptible strain. 

The aminoglycoside antibiotics are discussed in Chapter 45. Kanamycin has been used for treatment of tuberculosis caused by streptomycin-resistant strains, but the availability of less toxic alternatives (eg, capreomycin and amikacin) has rendered it obsolete. 

Mycobacteria. Most mycobacterial species seem to be harmless saprophytic soil bacteria of the grampositive group. However, tuberculosis (caused by Mycobacterium tuberculosis) may infect one-third of the inhabitants of the earth603 and kills about three million... 

Isoniazid (INH), rifampin, pyrazinamide, ethambutol, and streptomycin are the five first-line agents for treatment of tuberculosis (Table 47-1). Isoniazid and rifampin are the two most active drugs. An isoniazid-rifampin combination administered for 9 months will cure 95-98% of cases of tuberculosis caused by susceptible strains. The addition of pyrazinamide to an isoniazid-rifampin combination for the first 2 months allows the total duration of therapy to be reduced to 6 months without loss of efficacy (Table 47-2). In practice, therapy is initiated with a four-drug regimen of isoniazid, rifampin, pyrazinamide, and either ethambutol or streptomycin until susceptibility of the clinical isolate has been determined. Neither ethambutol nor streptomycin adds substantially to the overall activity of the regimen (ie, the duration of treatment cannot be further reduced if either drug is used), but they do provide additional coverage should the isolate prove to be resistant to isoniazid, rifampin, or both. Unfortunately, such resistance occurs in up to 10% of cases in the United States. Most patients with tuberculosis can be treated entirely as outpatients, with... 

Rifapentine is an analog of rifampin. It is active against both M tuberculosis and Mavium. As with all rifamycins, it is a bacterial RNA polymerase inhibitor, and cross-resistance between rifampin and rifapentine is complete. Like rifampin, rifapentine is a potent inducer of cytochrome P450 enzymes, and it has the same drug interaction profile. Toxicity is similar to that of rifampin. Rifapentine and its microbiologically active metabolite, 25-desacetylrifapentine, have an elimination half-life of 13 hours. Rifapentine is indicated for treatment of tuberculosis caused by rifampin-susceptible strains. The dose is 600 mg once or twice weekly. Whether rifapentine is as effective as rifampin has not been established, and rifampin therefore remains the rifamycin of choice for treatment of tuberculosis. 

In addition to pituitary-adrenal suppression, prolonged therapy with corticosteroids can cause fluid and electrolyte disturbances, hypertension, hyperglycemia, and glycosuria. It also increases the susceptibility to infections including tuberculosis causes... 

Recently V-containing analogues of rhamnose have been proposed for treating diseases such as leprosy and tuberculosis caused by mycobacteria which contain rhamnose in the cell wall since rhamnose has no role in mammalian metabolism. Design and synthesis of specific inhibitors of ihamnosidase have been reported [136,137],... 

The acid-fast bacillus M. tuberculosis causes tuberculosis. After years of steady decline, the number of cases of pneumonia caused by... 

Duration of therapy for extrapulmonary tuberculosis caused by drug-resistant organisms is not known. Corticosteroid preparations vary among studies. 

M. kansasii and M. tuberculosis cause similar disease. Therapy of the former with isoniazid, rifampin, and ethambutol has been successful. Mycobacterium marinum causes skin lesions. 

Within a few days of initiation of treatment for tuberculosis, laboratory staining results of Ivy Sharer s sputum confirmed the diagnosis of pulmonary tuberculosis caused by M. tuberculosis. Therefore, the multidrug therapy, which included the antibiotic rifampin, was continued. Rifampin binds to the RNA polymerases of several bacteria. M. tuberculosis rapidly develops resistance to rifampin through mutations that result in an RNA polymerase that cannot bind the complex structure. Simultaneous treatment with a drug that works through a different mechanism decreases the selective advantage of the mutation and the rate at which resistance develops. 

Florfenicol (2) has been approved in Japan for the treatment of pseudo-tuberculosis caused by Pasteurellapiscicida and streptococcosis fish. 

D. Cycloserine Cycloserine is an antimetabolite that blocks the incorporation of D-Ala into the pentapeptide side chain of the peptidoglycan. Because of its potential neurotoxicity (tremors, seizures, psychosis), cycloserine is only used to treat tuberculosis caused by organisms resistant to first-line antituberculous drugs. 

There are two dreadful diseases produced by the species Mycobacterium, namely tuberculosis caused by the organisms Mycobacterium tuberculosis and leprosy produced hy Mycobacterium leprae. Unfortunately both these diseases have afflicted the mankind throughout the recorded history. 

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