Tuberculosis primary infection

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

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. 

Addisons disease, results from progressive destruction or dysfunction of the adrenal glands by a local disease process or systemic disorder (Box 51-12), Worldwide, infectious diseases are the most common cause of primary adrenal insufficiency and include tuberculosis, fongal infections (histoplasmosis and cryptococcosis), and cytomegalovirus infections. Autoimmune adrenalitis accounts for more than 70% of cases reported in the Western world, with adrenal autoantibodies noted in more than 75% of cases,. The adrenal glands are atrophic, with loss of cortical cells but an intact medulla. Almost 50% of patients with autoimmune adrenalitis have an associated autoimmune disease with autoimmune thyroid disease the most common. 

Primary infection usually results from inhaling airborne particles that contain M. tuberculosis These particles, called droplet nuclei,... 

Infections may be caused by reactivation of a primary infection in the recipient, reactivation of a lesion from the donor lung, or as a primary infection. The (Morales et al. 2005) increase in the number of solid organ transplants has resulted in an increased incidence of opportunistic infections, including infection by typical and atypical mycobacteria, with the risk of developing tuberculosis. Pretransplant chemoprophylaxis with isoniazid has become increasingly common in an attempt to prevent the disease. The source of infection in tuberculosis (TB) may be difficult to identify. There are few reports on TB in lung transplantation (Baldi et al. 1997 Miller et al. 1995). 

Aiititubercular drug s are used in combination with other aiititubercular dm to treat active tuberculosis. Isoniazid (INH) is the only aiititubercular drug used alone While isoniazid is used in combination with other drains for the treatment of primary tuberculosis, a primary use is in preventive therapy (prophylaxis) against tuberculosis. For example, when a diagnosis of tuberculosis is present, family members of the infected individual must be given prophylactic treatment with isoniazid for 6 months to 1 year. Display 12-1 identifies prophylactic uses for isoniazid. 

Intended for use concomitantly with other antituberculosis agents in pulmonary infections caused by capreomycin-susceptible strains of Mycobacterium tuberculosis, when the primary agents (eg, isoniazid, rifampin) have been ineffective or cannot be used because of toxicity or the presence of resistant tubercle bacilli. Administration and Dosage... 

After oral administration, it is rapidly absorbed and is distributed in various body tissues including CSF. It is excreted largely unchanged in urine by glomerular filtration. It is used for treatment of multidrug resistant tuberculosis with other primary drugs. It is also used in acute urinary tract infections caused by susceptible microorganisms. 

Acquired immunodeficiency renders a host much more susceptible to secondary infections, including cytomegalovirus, syphilis, herpes zoster, fungi, hepatitis B, tuberculosis, and toxoplasmosis. HIV invades the tissues of the optic nerve and initiates an immune complex-mediated response that results in an optic neittopathy. The primary HIV infection may be responsible for color vision defects, loss of contrast sensitivity, and visual field defects. HIV infection itself may also cause direct degeneration of retinal ganglion cell axons in the optic nerve without a secondary opportunistic infection. 

Silicosis, a form of pulmonary fibrosis, is the primary health problem resulting from inhalation exposure to particles of crystalline silica (SSDC, 1988 NIOSH, 2002 Castranova, 2000 Castranova and VaUyathan, 2000). Other diseases associated with occupational inhalation exposure to crystalline silica include lung cancer, chronic obstructive pulmonary disease, nonmalignant respiratory disease, auto-immune related diseases (such as rheumatioid arthritis), renal diseases, and (as a complication of silicosis) increased risk of bacterial or fungal infections such as tuberculosis. Skin granulomas or obstructive lymphopathies may result from dermal exposure and uptake of silica particles (NIOSH, 2002). 

Tuberculosis. Recent experimental evidence suggests that exposiue to Mycobacterium tuberculosis may reduce the risk of developing asthma. In a partly longitudinal study of children in Japan, an inverse relationship was found between tuberculin skin response, allergen-specific IgE and symptoms of asthma. However it is unclear whether Bacille Calmette Guerin (BCG) vaccination, primary tuberculous infection in childhood, or sensitisation to harmless environmental mycobacteria were responsible [155(111)]. (BCG vaccination is discussed below under Immunisation .)... 

Infections caused by Mycobacterium tuberculosis are treated with combination therapy. The primary drugs used are isoriazid, rifampin, ethambutol, and pyrazinamide. Highly resistant organisms may require the use of additional agents. Backup drugs include aminoglycoside, fluoroquinolones, capreomycin, and cycloserine. 

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... 

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