Wednesday, November 17, 1999

MCS: a quick heart test
By Satish Misra
Metro Coronary Screening (MCS) helps in detecting all sorts of blockages in the most certain way like coronary angiography, claims Dr Purshotam Lal while talking to TNS about a new technique being practised by him at the Metro Hospital and Heart Institute, Noida, near the Union Capital.

AIDS: are you at risk?
By Dr Navneet Wig
It is almost certain that you have heard quite a bit about HIV and AIDS. These are closely related. HIV or the human immunodeficiency virus causes AIDS — acquired immunodeficiency syndrome. A virus is one of the smallest "germs" that can cause disease. In AIDS the body's immune system breaks down.

TB: eliminating the enemy
By Dr S.K. Jindal

The preventive strategy involving BCG vaccination has not succeeded in the case of tuberculosis. One can hope for the invention of a new vaccine against the causative agent of tuberculosis, that is, Mycobacterium tuberculosis (MTB). Efforts in this direction are on at various centres.

Newer vaccine designs are being conceived. It has been suggested from animal experimental studies that recombinant antigens administered as DNA vaccines can protect one against TB. The sequencing of the MTB genome has greatly improved our understanding. There are some 4,000 genes in the MTB genome and any one of the sub-unit can be used to produce a potential vaccine. But it is likely to be quite a while when one would find a workable vaccine.

We are left with the only option—eliminate the microorganism. It is a difficult proposition,but nonetheless an achievable goal. Fortunately, we have got very effective weapons—drugs against MTB.

This is unlike many other infections which are otherwise preventable by vaccinations. For example, we have very effective vaccines available for many viral infections such as polio, measles, mumps, rubella, chicken pox, hepatitis and rabies,but no real cure. For tuberculosis, an effective drug treatment is available, but the preventable vaccination is of little help. We, therefore, have to rely on the drugs for both treatment and prevention.

There are four to six drugs which are useful for the primary treatment of tuberculosis as a first choice. At least three, preferably four drugs, are used in the initial intensive phase of treatment of two months. This is followed by another four months of the maintenance phase involving the administration of two potent drugs. The whole idea is to maximise the attack against the mycobacteria at the very onset. There is no point in keeping the primary drugs in reserve.

The policy listed above is applicable to all the newly diagnosed patients of tuberculosis irrespective of the site of the lesion. There are a few variations in treatment based on the patient's clinical status, tolerance, acceptability and the presence of concomitant conditions (such as pregnancy) or diseases (such as diabetes).

Similarly, one has to look into some of the problems of drug-interactions in case other drugs are being used for different purposes. These are the considerations essentially meant for the doctors. It should be adequate for the patient to understand the importance of regular drug treatment.

It is most unfortunate that in spite of the effective treatment-availability, not all patients get well. There are some unpreventable factors while others are potentially preventable. Treatment response, for example, is poor if the disease is far advanced and the organ damage has already occurred, if the microorganisms are resistant to the drugs, if there is a state of immunodeficiency or the presence of other complicating illnesses. Retreatment patients would also behave differently from those who receive treatment for the first time.

More than the factors listed above are the reasons that can be avoided, but responsible for treatment-failure. Everyone shares the blame on this score. There are irregularities of treatment compliance. Patients often take an inadequate number of dosages of drugs, stop the treatment earlier than required or continue in an interrupted manner. The drugs are also discontinued or interrupted because of their cost intolerance, interactions, side-effects or on wrong advice and beliefs. The overall estimates indicate that of every hundred patients who have started antitubercular treatment, only one third would complete the course. This is a highly unsatisfactory rate of treatment-completion.

Besides the patients themselves, other factors which contribute to treatment inadequacies are the errors in drug-prescription, widespread prevalence of drug confusion, on-the-shelf availability and inferior brands of drugs. The problems of the Tuberculosis Control Programme are equally enormous. The drug supply and distribution under the programme suffer from numerous administrative and managerial shortcomings attributed partly to lack of funds, but largely to red-tapism and inadequate insensitive systems.

The crux of the matter is the continued propagation of the enemy—MTB—in society. Inadequate treatment not only fails to eliminate the organism but also helps to strengthen its attack by making it resistant to drugs and thus continue to survive

In the initial strategy to control tuberculosis, it was hoped that the treatment of a large number of patients should effectively reduce the total pool of patients who could infect other healthy individuals. As determined by the natural law of survival a diminished pool of the organisms, rendered weak by drugs, would go on weakening and perhaps disappear in the long run. Almost the reverse has happened in the case of tuberculosis and many more people will get the infection—and the disease.

To take care of treatment-compliance, the Central Government has now adopted the revised policy of administration of drugs, especially during the initial intensive phase of two months, under the supervision of a doctor or other health personnel. The strategy called Directly Observed Therapy—Short Course (DOTS) has been shown to succeed in a number of other countries and has already been made operational in several districts of India.

Although laborious in administration, this is an effective plan. Its implementation is a real challenge to the health administrators and society in general. One is yet to see widespread application of the programme in our set-up and has to wait for the results from the field.

The maintenance of sanitary and hygienic conditions is the other important step in controlling infections, including that of tuberculosis. The era of isolating patients of tuberculosis is long gone. All the sufferers are required to be treated within the four walls of their houses.

What steps are important to prevent the spread is a frequently asked question. The proper disposal of the patient's sputa is very important. Direct exposure to cough should be avoided. It may be important here to mention that only a sputum-positive patient is likely to infect others, especially children and those adult individuals who were not previously exposed to MTB.

Those who suffer from tuberculosis of organs and sites other than the lungs, and whose sputa are repeatedly negative for MTB, are not infective for others.

Antitubercular drugs, generally one or two, have been advocated for use in high-risk groups and those in close contact with a patient to prevent infection. This is especially so in the case of a baby born to a mother suffering from active tuberculosis. Doctors, nurses and other personnel working in hospitals need to be careful. The use of standard practices of cleanliness and sterilisation must be followed. Fortunately, widespread concern and the use of drugs for prevention are not yet warranted.

Tuberculosis, concomitantly with the HIV infection, is going to test our nerves in the days ahead. One can choose to be negligent only at the cost of one's health, and possibly one’s very existence.

(Concluded)

Dr Jindal is Additional Professor and Head of the Department of Pulmonary Medicine, PGI, Chandigarh.

MCS: a quick heart test
By Satish Misra

Metro Coronary Screening (MCS) helps in detecting all sorts of blockages in the most certain way like coronary angiography, claims Dr Purshotam Lal while talking to TNS about a new technique being practised by him at the Metro Hospital and Heart Institute, Noida, near the Union Capital.

Dr Lal, who heads the institute set up three years ago, says that the technique is not only less expensive; it is also patient-friendly. It takes just 10 minutes.

Born at Patto Hirasingh in Moga district in Punjab, Dr Lal said last week that "no patient suffering from a heart disease goes back from my hospital for want of resources". He said that while similar hospitals in the Union Capital were given land at a concessional rate by the Government, Metro Hospital did not turn patients back for lack of money even when it did not receive any official grant or assistance.

Dr Lal, who got his first medical degree from Amritsar, said that "our costs are comparable to those of the All-India Institute of Medical Sciences and much less than the rates charged by leading private hospitals". Metro Hospital has been constructed on a piece of land purchased at the market rate.

About MCS, he said that the test costs as much as tress thallium and half of the fast CT scan. The total time taken by the procedure is 10 minutes. The stay in the hospital, including registration, consultation and reporting is not more than an hour.

It could be compared with spending time for getting an x-ray or ultrasound test done in the hospital. The discomfort is comparable to giving a blood sample for a sugar or cholesterol test. "There is no risk and yet we get all the information about the coronary arteries which we get with conventional angiography. You don't have to take off your clothes. Just get the coronary screening, have a cup of tea and go to your workplace. The report is given immediately and becomes part of the permanent record to be interpreted by a physician".

Seventyfive million people are suffering from coronary heart disease in India and in more than 50 per cent of these individuals, it can present with sudden death, heart attacks or unstable angina. It is the single biggest killer of persons over 30 years of age in India — barring infectious disease — claiming more than 25 lakh lives every year. India is now leading in the world in the incidence of heart disease. Crores of rupees are spent every day to treat the unfortunate patients who generally come to hospitals after massive heart attacks and after spending lakhs of rupees. Small children become parentless and young individuals become old in the prime of their lives.

Many people spend the major part of their earnings on daily medication and their family members are always worried about "the future attack". The majority of the heart attacks happen suddenly; many of these patients never had any complaint before. It is in this group of patients that it has been seen that they had only 50 per cent of the arteries blocked.

Currently available non-invasive facilities like stress ECG (TMT), echo cardiography and stress thallium are unable to detect such blocks.

The recently introduced fast CT scan is based on the calcium content in the block and may miss almost half of the potentially dangerous blocks in young individuals in whom the blocks are laden with fat without any calcium, Dr Lal points out.

The only gold standard over the decades has been angiography which unfortunately carries avoidable phobia because of hospitalisation, discomfort, the cost involved and the risk. The goal of Metro Coronary Screening addresses three groups of people. The first group consists of those in whom the coronary screening has been found normal. These individuals are reassured and are advised to keep healthy habits. If the individual is taking any medicine for a heart disease, it is discontinued, saving a large amount of money.

The second group of individuals involves the ones who have about 50 per cent of blocks in their major arteries. It is this group in which aggressive modification of risk factors like no smoking, a low-cholesterol diet, proper control of blood pressure, along with yoga, meditation and breathing exercises is advised. It is that very group of people which never had any problem or never sought any medical advice. But a plaque may rupture at the 50 per cent blocked site causing a total block in the artery and thereby cause a heart attack.

The third group includes those who are having potentially dangerous blocks compatible with life. Some sort of intervention in the form of angioplasty or bypass is advised to save the person from a possible heart attack or a cardiac arrest. Coronary screening is advised for individuals generally after the age of 30. They may have more than one risk factor like smoking, diabetes, high cholesterol, hypertension, a family history of heart disease, obesity, extremely stressful sedentary life etc.

The test should be done even if such persons have no complaint. It is also recommended for the asymptomatic individual who has suffered a heart attack previously. This may prevent another heart attack. The concept has been introduced for the first time. It will prove to be a boon for the Indian population if it is implemented by experts, says Dr Lal. — TNS

AIDS: are you at risk?
By Dr Navneet Wig

It is almost certain that you have heard quite a bit about HIV and AIDS. These are closely related. HIV or the human immunodeficiency virus causes AIDS — acquired immunodeficiency syndrome. A virus is one of the smallest "germs" that can cause disease. In AIDS the body's immune system breaks down.

Normally, the immune system fights infections and certain other diseases. When it fails, a person with AIDS can develop a variety of life-threatening infections and other illnesses. You can be infected with HIV and have no symptoms at all. You may feel perfectly healthy, but if you are infected, you can pass the virus to anyone with whom you have unprotected sex or share needles or syringes. About half of the people infected with HIV develop AIDS within 10 years, but the time between infection with HIV and the onset of AIDS can vary greatly.

The severity of HIV-related illnesses differs from person to person, according to many factors, including the overall health of the individual. Today there are promising medical treatments that can postpone many of the illnesses associated with AIDS. The HIV infection and AIDS are controllable. In the meantime, people who get medical care to monitor and treat their HIV infection can carry on with their lives, including their jobs, for longer than even before.

One can become infected with HIV in the following ways:

• Sexual transmission by having unprotected sexual intercourse—vaginal, anal, or oral—with an HIV-infected person.
• Transmission of the HIV infection from an HIV-infected mother to her child during pregnancy or during childbirth or during breast-feeding.
• Sharing drug needles or syringes with an infected person.
• Transmission by blood and blood products.

HIV can be spread through sexual intercourse—male to female, female to male, from male to male, and from female to female. HIV is one of the sexually transmitted diseases (STDs). If you have any of the STDs and engage in a sexual activity that can transmit HIV, you are at a greater risk of getting infected with HIV. HIV may be in an infected person's blood, semen or vaginal secretions.

HIV can enter the body through cuts or sores in skin. HIV can also enter the body through the moist lining of the vagina, penis, rectum, or even through the mouth, in which case cuts or sores in these areas greatly increase the risk of infection.

Some of these cuts or sores are so small that you may not even know they're there.

Many infected people have no symptoms and may not have been tested. If you have unprotected sex with one of them, you put yourself in danger. Also the more sex partners you have, the greater is your chance of encountering one or more who are infected, and of becoming infected yourself. The only sure way to avoid infection through sex is to abstain from sexual intercourse or engage in such activity only with someone who is not infected. And you have to use condoms correctly every time!

A woman infected with HIV can pass the virus on to her baby during pregnancy, while giving birth or when breast-feeding. In developing countries, nearly 1,000 newly infected babies are born each day. If a woman is infected before or during pregnancy, without medical treatment, her child has about one chance in four of being born with the HIV infection. Pregnancy and HIV are complex issues. Motherhood is the innate desire of all women and it cannot be denied.

Proper counselling should be available for HIV-infected women so that they can make an informed choice. Any woman who is considering having a baby and who thinks she might have done something that could have caused her to become infected with HIV—even if this occurred years ago—should seek counselling and testing for HIV infection to help her make an informed choice about becoming pregnant.

The prevention of the transmission of the HIV infection during pregnancy is the single most important factor in decreasing the number of HIV-infected patients. There is a ray of hope for the developing world in this regard. "Short course" oral zidovudine given to women late in the last four weeks of pregnancy and during labour is effective for preventing perinatal transmission of HIV. There must be no breast-feeding by the infected mother. This regimen is estimated to cost roughly Rs. 5,000. The preliminary results find ZDV safe and effective in reducing HIV transmission by 50 per cent. Thus this regimen is the minimum which should be offered to all HIV-infected pregnant women. There has been advancement in the understanding of the pathogenesis of the HIV infection and in the treatment and monitoring of HIV disease. More aggressive combination during regimens that maximally suppress viral replication are now recommended. Standard highly active antiretroviral therapy should be discussed with and offered to HIV-infected pregnant woman in the developing world. The point which needs to be stressed, is that ZDV chemoprophylaxis should be offered to all pregnant women and incorporated into all antiretroviral regimens.

The HIV infection doesn't "just happen." You can't "catch" it like flu or a cold. Unlike the flu or cold viruses, coughs or sneezes do not spread HIV.

You won't get HIV through everyday contact with infected people at school, work, home or anywhere else.

You won't get HIV from eating food prepared by an infected person.

You won't get HIV from a mosquito bite. You won't get it from bedbugs, lice, flies or other insects either.

You won't get HIV from clothes, phones or toilet seats. Things like forks, cups or other objects that someone who is infected with the virus has used do not pass it on.

You won't get HIV from contact with sweat, saliva or tears. You won't get HIV from a simple kiss, though deep or prolonged kissing may be avoided.

You cannot tell by looking at someone whether he or she has the HIV infection. Someone can look and feel perfectly healthy and still may be infected. Many people who have the HIV infection do not know it. Neither do their sex partners. The only way to tell if you have been infected with HIV is by taking an HIV-antibody blood test. When any virus enters your body, your immune system responds by making proteins called antibodies. You make antibodies against HIV when you have the HIV infection.

HIV antibody tests are available at many standard laboratories. It is important that you discuss what the test may mean with a qualified health professional, both before and after the test is done.

ELISA (Enzyme-Linked Immunosor-bant Assay) is a screening test that is widely available. It can be performed quickly and easily. If a reactive (so-called "positive") result occurs, the test is repeated to check it. The other screening tests available are rapid tests and simple tests. These screening tests are highly sensitive but some false positive results do occur. Thus it is imperative that repeat testing is done in duplicate before the sample is considered positive by the screening assay. "Positive result" means that antibodies to HIV were found in your blood. This means you have HIV infection. Your condition is called HIV-positive or seropositive. "Negative result" means you are seronegative. Testing negative does not mean you are immune to HIV. No one is immune to HIV. Even if you test negative, there are steps you should take to protect your health and the health of your sex partner. Prevention is the only cure for HIV\AIDS.

Dr N. Wig, is Assistant Professor of Medicine at the All-India Institute of Medical Sciences, New Delhi.