Latent tuberculosis infection

Tuberculosis (TB) is a communicable infectious disease caused by Mycobacterium tuberculosis. It can produce silent, latent infection as well as progressive, active disease. 

Recommended Drug Regimens for Treatment of Latent Tuberculosis (TB) Infection in Adults... 

Isoniazid Inhibits synthesis of mycolic acids, an essential component of mycobacterial cell walls Bactericidal activity against susceptible strains of M tuberculosis First-line agent for tuberculosis treatment of latent infection less active against other mycobacteria Oral, IV hepatic clearance (half-life 1 h) reduces levels of phenytoin Toxicity Flepatotoxic, peripheral neuropathy (give pyridoxine to prevent)... 

Varicella-zoster virus is a member of the Herpesviridae femily. The viral contagion is transmitted via aerosolized water droplets or close physical contact with infected lesions. The primary infection results in varicella or chickenpox. The varicella infection can have potentially devastating ocular sequelae the most common is anterior uveitis followed by SPK. After the primary infection, latent infection occurs in multiple ganglia throughout the body. Herpes zoster is the resultant reactivation of the latent varicella-zoster virus and most often occurs in elderly and immunocompromised patients. Factors such as physical and emotional trauma, immunosuppressive medications, irradiation, cancer, tuberculosis, malaria, and syphilis are known to reactivate the virus. 

Adverse reactions that have been reported include infections, fever, headache, vertigo, hypertension, skin reactions, fatigue, chest pain and worsening congestive cardiac failure, gastrointestinal upset. Active tuberculosis may develop soon after starting treatment with infliximab and patients should be screened for latent infection or disease. 

Globally, roughly 2 billion people are infected by M. tuberculosis, and roughly 2 to 3 miUion people die from active TB each year despite the fact that it is curable. " In the United States, about 13 million people are latently infected with M. tuberculosis, meaning that they are not currently sick but that they could fall iU with TB at any time. The United States had over 15,000 new cases of active... 

Because young children, the elderly, and HIV-positive patients are at greater risk of active disease once infected with M. tuberculosis, they require careful evaluation. Once active TB is ruled out, they should receive treatment for latent infection. ... 

CHEMOPROPHYLAXIS OF TUBERCULOSIS Chemoprophylaxis of tuberculosis involves treating latent infection to prevent progression to active disease. Latent infection may be... 

Ha S-J, Jeon B-Y, Kim S-C, et al. (2003). Therapeutic effect of DNA vaccines combined with chemotherapy in a latent infection model after aerosol infection of mice with Mycobacterium tuberculosis. Gene Ther. 10(18) 1592-1599. 

Mycobacterium tuberculosis is one of the most successful pathogens of humans. Approximately one third of the world s population harbours latent infection with M. tuberculosis with no ill effect. Reactivation of infection in a small proportion of these subjects leads to progressive lung inflammation with necrosis, and the resulting cavitation permits aerosol spread of the mycobacterium to others. Following acute infection with M. tuberculosis, 5% of subjects will develop primary... 

Gomez-Reino JJ, Carmona L, Angel Descalzo M. Risk of tuberculosis in patients treated with tumor necrosis factor antagonists due to incomplete prevention of reactivation of latent infection. Arthritis Rheum 2007 57(5) 756-761. 

Any hazards peculiar to the particular animal species (e.g., common latent infections such as tuberculosis in nonhuman primates). 

About 1.8 billion individuals, or about one-third of the world s population, are infected with Mycobacterium tuberculosis, and most of these individuals have latent infection. Although malnutrition is a major risk factor for the progression of tuberculosis, tuberculosis control programs have tended to focus upon chemoprophylaxis and chemotherapy alone, rather than upon improvement of host nutritional status. For over one hundred years, cod-liver oil, a rich source of vitamins A and D, was used as a treatment for tuberculosis. The role of nutrition and tuberculosis remains a major area of neglect, despite the promise that micronutrients have shown as therapy for other types of infections and the long record of the use of vitamins A and D for treatment of pulmonary and miliary tuberculosis in both Europe and the United States. A recent clinical trial suggests that high dose vitamin A supplementation does not alter the morbidity of tuberculosis in children [65]. Studies have not been conducted which address the use of multivitamins and minerals or vitamins A plus D as an adjunct therapy for tuberculosis. 

Prior to initiating infliximab, obtain a tuberculin skin test to rule out latent tuberculosis. Assure that patients do not have a clinically significant systemic infection or New York Heart Association Class III or IV heart failure. 

Design, evaluate, and assess appropriate regimens for the treatment of latent tuberculosis infection (LTBI) in all patient populations. 

Latent tuberculosis infection (LTBI) can lead to reactivation disease years after the primary infection occurred. 

Worldwide, tuberculosis (TB) kills about 2 million people each year, more than any other infectious organism. TB is caused by Mycobacterium tuberculosis, it presents either as latent TB infection (LTBI) or as progressive active disease.1 The latter typically causes progressive destruction of the lungs, leading... 

Centers for Disease Control and Prevention. Update Fatal and severe liver injuries associated with rifampin and pyrazinamide for latent tuberculosis infection, and revisions in the American Thoracic Society/CDC recommendations. Morb Mortal Wkly Rep MMWR 2001 50(34) 733-735. 

Infections Corticosteroids may mask signs of infection, and new infections may appear during their use. There may be decreased resistance and inability of the host defense mechanisms to prevent dissemination of the infection. Restrict use in active tuberculosis to cases of fulminating or disseminated disease in which the corticosteroid is used for disease management with appropriate chemotherapy. Corticosteroids may exacerbate systemic fungal infections and may activate latent amebiasis. 

Evaluate patients for latent tuberculosis infection with a tuberculin skin test. Initiate treatment of latent tuberculosis infection prior to therapy with infliximab. 

Treatment of latent tuberculosis infection (LTBI) with isoniazid (INH) is very effective in preventing persons infected with M. tuberculosis from developing tuberculosis, regardless of HIV-1 serostatus. Several recent studies have shown that rifampicin and pyrazinamide taken for 2 months is as effective as 6-12 months of INH for the prevention of active TBC in HIV-1 seropositive persons although more hepatotoxicity is seen. 

Rifampin is a first-line antitubercular drug used in the treatment of all forms of pulmonary and extrapul-monary tuberculosis. Rifampin is an alternative to isoniazid in the treatment of latent tuberculosis infection. Rifampin also may be combined with an antileprosy agent for the treatment of leprosy and to protect those in close contact with patients having H. influenza type b and N. meningitidis infection rifampin is also used in methicillin-resistant staphylococcal infections, such as osteomyelitis and prosthetic valve endocarditis. 

Rifabutin appears as effective as rifampin in the treatment of drug-susceptible tuberculosis and is used in the treatment of latent tuberculosis infection either alone or in combination with pyrazinamide. Clinical use of rifabutin has increased in recent years, especially in the treatment of HIV infection. It is a less potent inducer of cytochrome 450 enzymes pathways than rifampin and results in less drug interaction with the protease inhibitors and nonnucleoside reverse transcriptase inhibitors. Rifabutin is therefore commonly substituted for rifampin in the treatment of tuberculosis in HIV-infected patients. Another important use of rifabutin in the HIV-infected population is prevention and treatment of disseminated MAC. 

Update fatal and severe liver injuries associated with rifampin and pyrazinamide for latent tuberculosis infection. MMWR 2001 50 733-735. 

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