Tuberculosis (Mycobacterium Tuberculosis / TB)

Tuberculosis is an ancient disease that remains one of the leading causes of death. According to one estimate, about half of the world's population is infected with Mycobacterium tuberculosis, the major causative organism. Of these, 30 million have active tuberculosis, with 10 million new cases and 3 million deaths each year.

In the United States, tuberculosis is relatively rare, but there has been an alarming increase in recent years, especially among impoverished people who live in crowded, unsanitary conditions, persons with AIDS, and the elderly. The incidence of the disease among African-Americans in all age groups is twice that of Caucasians.

The disease spreads when a person inhales the M. tuberculosis bacilli expelled into the air from the lungs of someone who has an active infection. Typically, when the bacilli enter the lungs, they set off an inflammatory response. Attacking white blood cells, called macrophages, carry the bacilli to lymph nodes, where most are eventually destroyed. Those that escape into the bloodstream travel through the body, prompting the immune system to produce antibodies against them.

About 95 percent of patients in the United States with disseminated primary TB heal completely, and most are unaware that they have been exposed. Even so, these individuals still harbor the bacilli, which can be reactivated later.

The scenario is quite different for people who are malnourished or weakened by age or disease. In some, the bacilli quietly multiply for months or years before producing symptoms. Others may show signs of TB within a few weeks; weight loss, fatigue, a chronic fever, and night sweats are common. Pulmonary TB is the most frequent type, signaled by a chronic cough that may produce blood-streaked sputum. Less often, the infection attacks the kidneys, brain, heart, liver, spine, and other organs and bones.

Diagnostic Studies and Procedures

A positive reaction to a tuberculin skin test indicates the presence of TB antibodies, but it cannot diagnose an active infection. Skin tests also produce many false negative results, especially among AIDS patients and others who have weakened immune systems. A chest X-ray and other imaging studies can detect lesions typical of TB, but a diagnosis requires culling the bacilli from the sputum and other fluids or tissue.

Medical Treatments

Treatment of an active or recurrent infection entails taking anti-tuberculosis drugs, usually for at least six months. The most common are isoniazid (Nydrazid), rifampin (Rifadin and Rimactane), ethambutol (Myambutoi), streptomycin, and pyrazinamide. Typically, two or more medications are prescribed.

Drugs must be taken in adequate doses for the entire duration of treatment. Because they can cause numerous side effects, including diarrhea, liver and kidney problems, and hearing loss, many patients stop taking their medication as soon as they begin to feel better. This can result in reactivation of surviving bacilli that have developed resistance to the drugs.

The emergence of TB strains that arc resistant to multi-drug regimens is a growing threat, especially among the homeless, prison populations, and other groups of people who lack diligent medical supervision. New York and other urban areas have stringent programs that include, when necessary, institutionalization to ensure that TB patients take their medication.

Fulminating TB requires hospitalization for intensive drug therapy, usually in an isolation unit. After a few weeks of antibiotic treatment, most TB patients are no longer contagious. Even so, prophylactic isoniazid or rifampin may be prescribed for household members, such as young children, even though they may test negative for the disease. Antibiotics usually are recommended for asymptomatic persons who test positive for TB, to lower their risk for later activation of the bacilli. The BCG vaccine, which is made from a bovine strain of Mycobacterium, is safe and widely used in other countries, but its efficacy is doubtful.

Alternative Therapies

Alternative therapy must be approached as an adjunct to, not a substitute for, drug treatment.

Light Therapy. The M. tuberculosis bacilli are highly sensitive to ultraviolet light. Exposure to the sun or special sunlamps reduces transmission of the disease and may also promote healing.

Naturopathy and Nutrition Therapy. A balanced, nutritious diet emphasizing fresh fruits and vegetables, high-protein foods, and whole-grain products is critical. Also, extra calories are needed to counter the weight loss typical of TB.

Naturopaths usually prescribe supplements of vitamins C and A, selenium, and zinc to boost immune function, but you should check with your doctor before taking any high-dose supplement. Garlic, either fresh or in capsule form, is said to boost immunity, it is also a natural antibiotic.

Self-Treatment

Most importantly, comply with your drug regimen, even if your symptoms improve. Get adequate rest and consume balanced, nutritious meals. Abstaining from smoking and avoiding secondhand smoke are also crucial, and the house should be aired frequently, even in cold weather. A dry, sunny climate has traditionally been recommended to help speed recovery.

To avoid spreading the disease, always cover your mouth and nose when coughing, and dispose of used tissues immediately.

Other Causes of TB Symptoms

Pneumonia and lung cancer sometimes resemble TB on lung X-rays, and flu, bronchitis, and emphysema can cause coughing shortness of breath, and other symptoms similar to those of TB.