(This article is based upon a CNS interview with Professor (Dr) Dilip Mathai, Dean, Apollo Institute of Medical Sciences and Research)
HIV in today's context is a chronic condition of the human immune system. HIV is a retrovirus and the infection leads to a progressive reduction in the number of CD4+ T-helper cells (so called because CD4 glycoprotein is found on their surface) which are an essential part of the human immune system. They are the main targets of HIV which destroys infected CD4 cells leading to an overall weakening of the immune system, said Dr Dilip Mathai, Dean, Apollo Institute of Medical Sciences and Research, and former Head of Medicine Department, Christian Medical College (CMC), Vellore.
Dr Mathai was speaking with Citizen News Service (CNS) at 6th National Conference of AIDS Society of India (ASICON 2013). Dr Mathai added: Normal values for CD4 cells are 500-1200 cells/mm3. When CD4 cells become depleted, the body is left vulnerable to a wide range of infections that it would otherwise have been able to fight. Lower numbers of circulating CD4+ T-cells indicate a weakening of the immune system and advancement in the progression of HIV disease.
The goal of anti-retroviral therapy (ART) in HIV is to bring down the viral load and increase the CD4 cell count so that the body reconstitutes its immune system AND increases the CD4 count to a manageable level of 500 and more.
Co-infections and HIV beget each other. As the HIV infection progresses, it interferes more and more with the immune system, making the affect person more prone to contract infections, including opportunistic infections (OIs) that do not usually affect people who have strong immune systems. Co-infections like hepatitis B, hepatitis C, TB and pneumonia, among others, can cause a transient increase (which is called a blip) in the viral load and decrease the CD4 cell count, thus lowering the body’s ability to kill the co-infecting bacteria or virus. This can perpetuate other infections. For example, cure of TB depends both on drugs and the body’s defence mechanism to annihilate the TB bacilli. But if the CD4 count is very low and the viral load increases then the body defence against TB is not so good. The anti TB drugs help in decreasing the total number of TB bacilli, but to annihilate them completely requires the body’s defence mechanism for the drugs to penetrate the cells where the bacilli are. No wonder then that a lot many people living with HIV (PLHIV) die of TB and not of HIV.
In PLHIV there is not only the danger of acquiring co-infections but also the problem of eliminating them. HIV may be controlled through ART but co-infections can damage the body organs. Every co-infection (including HIV) has an effect on inflammation. This inflammation can take its toll of the blood vessels and affect the heart as coronary artery disease is the product of an inflammation. Another problem with co-infections is that some of them may not be systemic like cytomegalia virus of the eye, lung or bone marrow, and can damage the affected organ. In fact, for PLHIV, Hepatitis C and/or TB can be more worrisome for survival than even HIV. Then again diseases that can suddenly flare up, like chicken pox, can disseminate and be fatal in those who are immune compromised, like PLHIV. In a normal competent host chances of dissemination are very low. There can also be co-morbidities like diabetes, stroke, and renal problems as HIV can affect the heart, the kidney, and have secondary effect on the bones.
Thus there is a wide spectrum of diseases and issues to be dealt with for prevention, treatment, and management of HIV—TB and HIV, Hepatitis C/B and HIV, liver disease and HIV, kidney disease and HIV, nutrition and HIV, heart disease and HIV, to name a few. Doctors and other healthcare personnel need to be trained and also kept updated so that they are competent enough to handle their HIV patients well and not let them die of HIV related OIs. So a multi-disciplinary approach is needed—general physicians, specialists, paediatricians, gynaecologists, nurses, psychologists-- all holding hands and working together to ensure that PLHIV have the same quality of life as any other person.
Detecting and diagnosing new cases, enrolling them into care/treatment, retaining them in care and making them adhere to therapy and behavioural change-- all are equally important in controlling the HIV pandemic. There is no point in diagnosing if one cannot treat them; there is no point in holding them in care if they are not willing to be engaged to reach out to the others. We have to reach out to all, especially the young and other vulnerable populations, educating them about the hazards of unsafe sex which increases risk of HIV and other sexually transmitted diseases. In the absence of a cure, the disease will continue to be transmitted if people do not change their risk seeking behaviour like chemical dependence, unsafe sex, injecting drug use, among others. (CNS)