Partners in crime: MDR TB and HIV

MDR-TB manifests if a TB patient is not treated long enough, does not take the prescribed medication properly and/or is not prescribed the right drugs. This form of TB can take up to two years to treat it with drugs that are more toxic than the standard drugs, and the treatment is far more expensive.

MDR-TB has been shown to be almost twice as common in TB patients living with HIV (PLHIV) as in those who are not infected with HIV. A suppressed immune system makes PLHIV more vulnerable to both drug-susceptible and drug-resistant TB. They may also have decreased absorption of TB medicines, especially rifampicin, which may lead to the acquisition of drug-resistant strains of TB. The high pill burden and overlapping toxicities of the dual medication for MDR TB along with Anti Retroviral Therapy (ART) also make adherence big challenge. According to the World Health Organization MDR-TB guidelines "Antiretroviral therapy is recommended for all patients with HIV and drug-resistant TB, requiring second-line anti-tuberculosis drugs, irrespective of CD4 cell-count, as early as possible (within the first 8 weeks) following initiation of anti-tuberculosis treatment."

Dr Jose A Caminero from the International Union Against Tuberculosis And Lung Disease (The Union) is however optimistic that “with a good training and availability of drugs, most of the PLHIV affected by MDR-TB can be cured".

Dr Zarir F Udwadia of Hinduja Hospital and Research Centre, Mumbai blames the unregulated private market and a lackadaisical DOTS programme for this sorry state of affairs. He laments that, "The private sector in India, which manages more than half of all TB patients, lacks regulation in prescribing practice and the qualification of those prescribing drugs for TB. Our study from Mumbai in 2010 found only three out of 106 prescriptions of  Private Practitioners (PP) working in Dharavi, (Asia’s most populous slum), to be appropriate, in that they contained a minimum of three new Second Line Drugs (SLDs) in the right doses and for the right duration. The majority of prescriptions served to merely amplify resistance, with 70% of prescriptions only adding a single SLD (usually a fluoroquinolone). Thus poor prescribing practice by PPs is one of the key factors fuelling India’s MDR-TB epidemic."

He further says that, “India’s Revised National Tuberculosis Control Programme (RNTCP), has also failed to control the rising number of patients with MDR-TB. Patients whose condition fails to respond to DOTS category 1 treatment instead of promptly having treatment based on their drug susceptibility testing (DST), are subjected to the suboptimal category 2 treatment regimen which merely adds a single drug (streptomycin) to first-line, violating the basic tenet of ‘never add a single drug to a failing regimen’. This serves to amplify resistance over a further 8 months, allowing drug-resistant TB to spread among crowded communities. DSTs, when finally asked for when category2 treatment fails, take a further 2 months to arrive. By this time 16 months have elapsed, during which time patients have already disseminated resistant strains in crowded communities.”

India’s RNTCP has been able to provide standard treatment to only 3610 patients (less than 3% of those-in-need) since the inception of its DOTS-Plus programme. By its own admission, the RNTCP aims to deliver MDR-TB treatment to a maximum of 30,000 patients by 2013 thus leaving out 70,000 who will still be in dire need of it every year. Not being able to reach out to them is a serious public health and social justice issue. Mismanagement of MDR-TB at government and private care levels can result in amplifying TB drug resistance, even giving rise to virtually untreatable strains of extensively drug-resistant TB.

Professor (Dr) Surya Kant, Head of the Pulmonary Medicine Department at King George’s Medical University calls MDR-TB an iatrogenic problem. In his opinion, “Most of the times it is we doctors who are responsible for creating multidrug-resistance in society. If doctors are not educating the patients then how can we blame the patients that they have defaulted from the treatment? Patients do not know the consequences of defaulting from the treatment. It is the doctors’ community that has to educate and motivate the patient.”

Limited resources and lack of proper diagnostic facilities further compound the problem. According to Dr Anthony Harries, Senior Advisor and Director (Research) at The Union, “MDR-TB and HIV are a deadly combination and if one does not intervene timely to start antiretroviral therapy (ART), death rates become extremely high. It is important to test early for drug-resistant TB (DR-TB) and in high HIV burden areas to test for HIV, and to intervene with ART early enough. The way the global TB Control programme works in Africa, India and China, we do not do a sputum culture at the beginning of TB treatment, even though the patient may be having MDR-TB. It is only when the 1st line of treatment fails that we do the test for MDR-TB. So we pick up the correct diagnosis far too late and by then a lot of patients are already dead and/ or the infection has been transmitted to many others. So now there is more thinking on testing all TB patients for MDR-TB at the start of the diagnosis. This is really difficult given that though we have the Gene Xpert, a revolutionary machine which can actually diagnose TB in less than two hours and test for rifampycin resistance too, it is far too expensive to be used for the 9 million new TB cases each year. We need cheaper methods for timely diagnosis of MDR-TB.”

The importance of quality diagnostic centres can be illustrated from the example of Pune where within 5 months of establishing a referral laboratory in February 2012 at the Aund Chest Hospital, Pune, 141 MDR-TB cases have been detected till July 2012, out of the 539 sputum samples received from the district. 98 of these patients, including a 13 year old girl, are on Category IV treatment, according to information given by Dr Kanchan Jagtap, Director of the Laboratory.

However, in an interview given to the Wall Street Journal, Dr Ashok Kumar, Deputy Director General, Central TB Division (Ministry of Health and Family Welfare-Government of India), asserted that the threat of MDR-TB is overblown. He said, “It is better to suffer from TB than suffer from hypertension, diabetes or psychotic problem because TB is curable. Drug resistance in TB is nothing new. Tell me any disease which is not drug resistant. Let me tell you even your diabetes is drug resistant. Even your hypertension is drug resistant. But we can minimize the drug resistance if cases are diagnosed early, treatment starts early and we ensure that patient takes regular, complete treatment so drug resistance won’t be there.”

The Indian government has promised to expand its TB treatment system by 2017, with the goal of quickly diagnosing and treating MDR-TB cases. The allocation to fight TB has been more than doubled from Rs 400 crore in 2011--2012 to Rs 710 crore in 2012--2013. RNTCP 3 (for 2012–17) aims to provide universal access to quality diagnosis and treatment for the entire Indian population.  However, given the high costs of diagnostics and drugs needed, this seems to be a tall order. India has also banned serological tests and made TB a notifiable disease, which may yield some positive public health outcomes as all private doctors/laboratories will now have to report every single case of TB to the government which will surely give a more realistic analysis of the burden of TB. However, as of now, according to the RNTCP, it had achieved a ‘new sputum positive TB case detection rate’ of more than 73% in 2010 which implies that it is still not reaching to 27% of estimated number of people who need TB care services. Will making TB a notifiable disease really help us reach these unreached populations?

As Dr Paul Farmer, the famous medical anthropologist said: “Our mission must be to treat the sick, and not just the sick who can pay. Our mission must be to treat TB regardless of resistance pattern.” Let us hope that the AIDS 2012 will press the panic button to control the raging fire of TB and HIV and urge governments to strengthen their public health programmes and make them accessible to all in need with a view to turning the tide against these diseases.

Citizen News Service

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