Management of Tuberculosis: Therapeutic Approach

Pulmonary tuberculosis (Tuberculosis of lungs) or Extra-pulmonary tuberculosis (Tuberculosis of organs other than lungs) in humans is caused by Mycobacterium tuberculosis, a human tubercle bacillus. Mycobacterium tuberculosis is an obligate anaerobic bacterium, whose natural reservoir is human beings. Mycobacterium tuberculosis (MTB) is non-motile and does not produce spores. The generation time of MTB is 15 to 20 hours, so it is also called slow growing bacterium.

Tuberculosis (TB) of any type remains a challenging clinical problem and important public health issue the world over. In the recent past the World Health Organization (WHO) has documented an annual incidence of 9.27 million new cases of TB with a prevalence of 13.7 million cases. Majority of TB cases exist in Africa and South East Asia. The annual incidence rate in Africa and South East Asia has been reported as 356 and 182 cases per 100,000 population respectively that is much higher than the global incidence rate.

The ‘gold standard’ in the diagnosis of TB has been the detection of Mycobacterium tuberculosis in the sputum smear or in the pathological lesions (by histopathological methods). The rapid diagnosis of TB is fundamental to clinical outcome. On general physical examination careful attention should be given to the presence of lymphadenopathy (swollen/enlarged lymphnodes), draining sinuses, non-healing ulcers, spinal or joint lesions etc.

Extensive research has been going on in the field of management of TB through anti-tubercular treatment (ATT) ever since the discovery of rifampicin in 1960s. The major objectives of research in anti-tubercular treatment (ATT) include the shortening of duration of therapy, preventing the emergency of drug resistance, avoiding toxicity and shortening the period of infectivity. Direct Observation Therapy-Short Course (DOTS) is the most effective strategy propagated for the management of tuberculosis. Several new drugs and non-pharmacological therapeutic modalities are under extensive study for the effective management of tuberculosis.

A)  Pharmacological Approach to Management of TB:

Pharmacological drugs can be classified as

Ø  Drugs susceptible for MTB.

Ø  Drugs susceptible for conventional ‘drug-resistant bacilli’, which include the followings:

·         Re-purposed drugs (e.g. Fluoroquinolones)

·         New dosages of already available drugs (e.g. Rifampicin rifamycin or high dose isoniazid)

·         New drugs (e.g. Bedaquiline for ‘multi drug resistant-TB).

B)  Preventive Approach to Management of TB:

Ø  Vaccination: The use of BCG vaccination is recommended. Recombinant BCGs are also under clinical trials.

Ø  Chemoprophylaxis for Latent-TB: Chemoprophylaxis is recommended for new born babies born to ‘sputum smear positive’ mothers. Chemoprophylaxis should also be recommended for the cases having ‘Latent-TB’. Interferon gamma release assay test (IGRAs) and Mantoux Test (a Skin Test) are useful tests for establishing a diagnosis of Latent-TB. However, these tests do not necessarily indicate the presence of active tuberculosis and requirement of ATT.

C)  Non-pharmacological Approach to Management of TB:

Ø  Non-pharmacological advances are based on immunomodulation and immunotherapy. Use of protective cytokines, anti-cytokine agents (such as thalidomide pentoxiphylline) and immune-enhancement with ‘heat killed Mycobacterium vaccine’ and other recombinant BCGs have been under clinical trials. These modalities have not been recommended for standard clinical practice.

Ø  Strategies for Airborne Infection Control:  ‘International Guidelines on Airborne Infection Control in Healthcare Settings’ should be adopted. These guidelines are very important in the isolation wards, multi-drug resistant-TB (MDR-TB) wards and the Medical Laboratories conducting TB tests, for prevention of spread of infection among health workers in hospitals.

 

 

Jaundice: Should the Drugs be Used ?

Jaundice is a symptom of a liver disease wherein the level of a yellow colored pigment called bilirubin increases in blood. The cause of jaundice may be infectious, pathological, obstructive or therapeutic. However, the most prevalent cause of jaundice is due to viral infection. Till 1940 this disease was considered catarrhal (catarrhal jaundice), due to catarrh of bile passages responsible for transporting bile from the liver to the intestine. It was during World War-II (1939-1945), the attending physicians discovered that the disease is due to some infection; and it was labeled as 'infectious hepatitis'. Many soldiers died due to infectious hepatitis during the World War-II. It was also observed during the period of war that there are two viruses infecting the soldiers with relatively shorter and longer incubation periods.

Now, these hepatitis viruses are called hepatitis virus-A and hepatitis virus-B. We can accurately diagnose the cause of jaundice and classify the causative virus. Hepatitis-B is severer of the two. Disease is transmitted not only through transfusion of infected blood or blood products but also through saliva, tears, breast milk, and seminal fluid and rarely by feces and urine of the patient.

Fatigue, loss of appetite, nausea, vomiting, joint and muscle pains, cough, coryza and headache may precede for one to two weeks preceding the onset of jaundice. Dark colored urine and light colored stools are other visible signs in addition to yellow coloration of eyes. There may be pain in the upper right quadrant of tummy along with discomfort in the tummy. Progress of recovery is very encouraging in cases of Hepatitis-A.


The medical management in cases of viral hepatitis/jaundice is just symptomatic and maintenance of nutrition is taken care of in these patients. There is no specific treatment for viral hepatitis/jaundice. Restriction of physical activity is advisable. A high calorie diet is generally recommended but special care is required in diabetics. Drugs should be avoided to avoid adverse effect on the liver. Patient should be isolated to a room (and a bathroom too) and routine hygiene measures should be observed. Serious patients should be hospitalized.

Inimical Interaction of Tobacco with Drugs

Consumption of tobacco in any form is bad as it has inimical interaction with a majority of drugs/medicines in addition to its other bad effects and health hazards. There are thousands of chemical substances in the tobacco and the smoke of its products like cigarette and bidi. Nicotine, tar and carbon monoxide are three most damaging chemical substances present in the smoke of cigarette and bidi. Smoking and chewing of tobacco would affect your metabolism and physiology. Like cocaine and morphine; nicotine causes addiction to tobacco. Cigarette smoking speeds up your heart beat and increases blood pressure. It is major cause of emphysema (chronic obstructive lung disease leading to damage of alveoli), chronic bronchitis, coronary heart disease (CHD) and lung cancer. Carbon monoxide along with nicotine increases the prevalence of heart attack in smokers.

The tar present in the smoke of cigarette or bidi damages the delicate epithelial lining of lungs. The brown and sticky deposit produced by the tar is a cause of lung cancer in smokers. The nicotine content per cigarette has been estimated to 20-30 mg. The carbon monoxide remains in the blood of a smoker for 5-6 hours after he finishes a cigarette and keeps interacting with body metabolites and drugs. The tobacco that is chewed, kept in the mouth or snuffed has equally bad effects. The consumption of tobacco is like ‘slow motion suicide’ due to its bad effects and inimical interaction with large number of drugs taken for various health ailments:


Tobacco has been found to reduce the effectiveness of pain killers (analgesics), anti-asthma drugs, anti-coagulants and drugs used to treat heart ailments. The risk of cardiovascular diseases increases in women taking oral contraceptives.