World TB Day: A conversation with a TB warrior from India
Dr Zarir F Udwadia FRCP FCCP is a consultant chest physician at the Hinduja Hospital, Breach Candy Hospital and Parsee General Hospitals in India. He established an active chest department at the Hinduja Hospital, which includes Bombay’s busiest bronchoscopy and PFT services and the city’s first sleep laboratory. On World TB Day, we asked him about his experience diagnosing and treating this killer bacterial infection. His recent TED Talk was published for World TB Day 2017.
Today is World TB Day. Why did you become interested and involved in researching TB?
As a medical trainee in the UK I worked in Sir John Crofton's former TB unit in Edinburgh. He had long retired but was a towering name in the TB world. I didn't see much TB there in the UK but TB so dominated the pulmonary landscape in India when I returned that it formed the daily fare of any chest physician here.
I won't forget my first MDR-TB patient, a teenage Indian hemophiliac called Zubin Irani who had MDR (multi-drug resistant) before it became a buzzword in the early 1990’s. In desperate attempts to cure him I wrote to the foremost UK TB expert at the time, Prof Peter Davies, who was generous with his advice. Zubin sadly died of his disease but Peter and I became friends, and he invited me to write the chapter on MDR-TB in India in his textbook, Clinical Tuberculosis.
This made me go back to the roots of TB in India: reading every available reference on the subject, determined as I was to become an expert in the field. Peter and I spoke regularly at each other’s conferences across the world and I wrote the chapter in all the subsequent editions of his book as well. Around this time I set up my free TB OPD at the Hinduja Hospital, where in the early years MDR was rare. It’s been operating every Monday for the last 25 years, and is now the busiest clinic in the hospital. Over the years we had ring side seats to the relentless amplification of TB from M (multi-drug resistant) to X (extensively drug resistant) to T (totally drug resistant) strains.
My research is mainly clinical and my huge number of TB patients is who I’m indebted to, for every article has focussed on them. Truly, a single patient determined my career path, a single disease chose me.
TB was not included in WHO's recent list of priority bacteria for AMR. What do you think of this?
In 2011 we described the first cases from India of totally drug resistant (TDR) TB. These patients were resistant to all 12 of the 1st and 2nd line drugs available at the time and were therapeutically destitute. With such extreme patterns of resistance not infrequently encountered and with a drug larder that’s almost bare and benefit, it’s amazing TB was not included in WHO’s recent priority list for AMR. Surely a disease which kills 2 million people a year globally and one Indian every minute needs top priority.
How is TB different in different parts of the world?
There are two different TB’s: TB in the Western world, rarely encountered, usually in immigrants, usually drug sensitive, and easy to cure at the cost of a few dollars a course. And then there’s TB in much of the developing world: so frequently encountered it’s hard to be impervious to its presence, often MDR and costing thousands of dollars and 2 years of treatment with toxic drugs that have at best a 60% chance of cure. Sadly TB is the perfect expression of an imperfect and unjust civilisation.
What diseases does TB often get mistakenly diagnosed as?
TB is everywhere and is the great mimic. In India every disease is first considered to be TB. At the same time, paradoxically, TB can be notoriously difficult to diagnose, and the average time from first symptom (usually cough) to commencement of the correct drugs in a patient with MDR-TB approached 6 months in a recent study in Mumbai.
GeneXpert has been revolutionary in TB diagnosis and therefore treatment. However, the Longitude Prize is looking for a POC test that anyone can use, is rapid (less than 30 mins from sample to result) and is cheap. Do you think such a test is possible for TB detection, and how would this improve TB diagnosis and treatment?
A point of care test would be the game changer we’ve waited for so assiduously! India has only 0.4 GeneXpert machines per million population, when they should be as common as cash dispensers. So it’s a question of funding and scale up. I feel we’re close, however, and we can expect to see a POC test in the next decade.
Dr Zarir is an author in a Lancet Respiratory Medicine article published today for World TB Day: The epidemiology, pathogenesis, transmission, diagnosis, and management of multidrug-resistant, extensively drug-resistant, and incurable tuberculosis (open access)