The trouble with TB

A retired medical physicist, who has worked as a consultant in many cancer-speciality hospitals across the country and overseas, was diagnosed with tuberculous pericarditis (tuberculosis of the pericardium) 20 years ago. This form of tuberculosis (TB) is non-contagious but requires life-long treatment; he has to take a course of TB treatment every two years. Frequent low-grade fever and fatigue are his constant companions. He says, though debilitating, these symptoms did not affect his work much while he was on the job.

While in his case the disease was non-contagious, other forms of TB can be transmissible. Caused by the bacteria Mycobacterium tuberculosis, transmission depends on which part of the body is affected and whether TB is active or latent. A majority of those infected do not develop the disease as the bacteria exist in an inactive state; when the bacteria is latent, no symptoms are exhibited and the disease is not contagious. When TB is active, symptoms are manifested and the disease can be communicable.

Transmission

Uma Devaraj, assistant professor in the department of pulmonary medicine at St John’s Medical College and Hospital, Bangalore, says: “Transition to the active state depends on several factors, such as the immunity of the person and other risk factors. Diabetics, tobacco users, HIV-infected and immuno-compromised patients, cancer patients, alcoholics, intravenous drug users and health workers are at high risk of developing active TB. Other conditions that can induce the disease include malnutrition, indoor air pollution, lack of proper ventilation and crowding, migration, and poverty.”

“Only pulmonary TB, where the disease affects the lungs causing bacilli-ridden sputum to be expelled during coughing out in the air, is contagious. When a person inhales these air-borne bacteria, he/she is infected with TB. A person with active but untreated pulmonary TB can affect several other people in his/her vicinity. About 80% of active TB primarily affects the lungs, but it can also affect many organs in the body, like lymph nodes, kidney, and bones,” says Dr Devaraj.

In some active cases, the infection from the lungs can spread to other organs. A Bangalore-based MBA professional, currently in her late-30s, was diagnosed with TB when she was 7 years old after frequent bouts of cold and cough with heaviness in the chest. “After a prolonged treatment and several visits to hospital, by the age of 12, I was supposedly cleared of TB. But the medications available then were probably not very effective,” she says. She had difficulty in conceiving for several years after marriage. After consulting several doctors and going through various tests, all of which yielded normal results, a study of her medical history indicated that her childhood TB may have spread to the uterus. She was started on a new course of treatment for TB and within a few months she was able to conceive naturally.

While advances in the medical field now ensure complete cure, TB is a continuing concern in India. A 2011 World Health Organization (WHO) survey listed India as the highest TB “burden” country in the world with over 1 million new infections each year. “Forty per cent of India’s population carry the TB bacillus, so vulnerability to the disease is high in our country. But early diagnosis and treatment can help in curtailing the contagion. Those suspected with TB are diagnosed by a sputum test, which is conducted free of cost at all government hospitals and DOTS (Directly Observed Therapy Short-course) centres,” says Dr Devaraj.

The Revised National Tuberculosis Control Programme (RNTCP) was introduced in 1992 by the Union government and later revamped in 2005 to address India’s growing TB problem. The RNTCP is based on the DOTS approach of the Global TB Strategy of WHO, whose principle components are: case detection by sputum smear microscopy, uninterrupted supply of high-quality anti-TB drugs, standardized treatment regimens with directly observed treatment for at least the first two months, and systematic monitoring and accountability.

How is TB treated?

Soumya Swaminathan, director, National Institute for Research in Tuberculosis, Chennai, says: “The current protocol of treatment in the DOTS programme uses a combination of the antibiotics Isoniazid, Rifampicin, Pyrazinamide and Streptomycin as the primary TB drugs. Treatment must be taken at a designated RNTCP or DOTS centre and not at any private hospital or private clinic as the private sector is usually unregulated and it has been found that the doctors there prescribe inappropriate treatment and do not always follow the standardized regime.” A patient diagnosed with TB has to undergo treatment for six months, a combination of four drugs for first four months and two drugs for the next two months. In cases of relapse, retreatment includes a streptomycin injection along with four drugs for a period of eight months. While for MDR-TB (multi-drug resistance), the treatment regimen is two years long.

While the long duration of the treatment may be a challenge to adhere to, it is important to complete the course and not stop once the symptoms are alleviated or the patient feels better. “Incomplete treatment or non-adherence to the regime can lead to a relapse or may give rise to drug-resistant variants of TB. DOTS centres can help by keeping a track of the schedule of treatment and patients can also choose to go the centre every day to take the medications,” says Swaminathan.

Drug-resistant TB, where the disease does not respond to the first line of antibiotics, is difficult to treat and can also be transmitted to other individuals. The increasing number of drug-resistant cases is a major concern and obstacle in the control of TB in India and across the world. Several research groups are working towards finding better and shorter courses of treatment and one can hope that these will be made available in the near future.

How can one avoid getting TB?

Dr Devaraj says: “The BCG vaccine, given to infants at birth, protects against TB, but it is effective only in children. Even so, the vaccine protects only against severe forms of the disease and not from the infection itself. Adults who have received the vaccine as children can still develop the disease.” Exercise and a healthy diet to keep the immune system strong can help prevent active TB.

“There is unfortunately a social stigma attached to TB as it has been associated with poverty in the past and with HIV recently. As a result, patients either do not report it or come forward when it’s too late,” adds Dr Devaraj.Greater awareness can help in reducing the stigma associated with it and thereby in early diagnosis and timely treatment of TB. Remember TB is completely curable if one adheres to the standardized treatment protocol.