Disease that claimed Tiger is a grey area in research

“There is a broad spectrum of interstitial lung diseases,” said Dr Neeraj Jain,chief of the pulmonology department at Sir Ganga Ram Hospital,where he led the team treating Pataudi. “Pataudi was diagnosed with the most extreme form,idiopathic pulmonary fibrosis. Here,the thin membrane becomes swollen,there is scarring in the lungs. As a result the lungs cannot hold oxygen,despite external support.”

In milder forms,there is some swelling in the interstitial membrane but no scarring. “Though the cause of the swelling is not established,if it is mild it becomes manageable with steroids… the body adapts to a mild loss in the oxygen capacity of the lungs,” Dr Jain said.

There are hypotheses on what leads to ILD,though the precise cause is not clear. One theory involves reactions to toxic factors in the environment. Another is about auto-immune disorders — multiple sclerosis,scleroderma,Lyme disease — where the immune system reacts against the body. Reaction to certain drugs for cancer and cardiac problems,too,is believed to be a possible cause.

What leads to the fibrosis is again unclear. Dr S K Jindal,head of the country’s oldest pulmonary medicine department — at PGI Chandigarh — said,“The term idiopathoic is only used when the cause of the fibrosis of the interstitial membrane is unknown. We know that for some reason,there is a deposition of a fibrous substance called collagen that causes thickening of the membrane. But we do not know what causes this deposition.”

His department had reported what were possibly the first incidents of pulmonary fibrosis in the country in 1979 — 60 cases in five years. “Our second large-scale reporting was in the late 1990s when we found 200 cases over a period of five years. This shows that there has been a sharp rise though the absolute numbers will still be minimal,” he said. From anecdotal incidents now and then,he broadly estimated that doctors see about 1-10 cases in a population size of 1 lakh in India.

Treatment is symptom-based,with steroids to control the swelling. Dr Sundeep Salvi,director of the Chest Research Foundation in Pune,said,“The thickness of a normal interstitial membrane is 3-5 microns; for a patient of ILD it becomes about 8-9 microns. We try to target this with steroids. In the last six months,some new categories of immuno-suppressants have come in the market,and are showing results. These include drugs like pirfenidone.”

Lung transplant has sometimes been suggested but never tried in India. “Though we did consider it for Pataudi,his age (70) was a huge factor. Even abroad,when it has been tried,the results are not very promising,” Dr Jain said.

The lack of research is attributed to cost. “Research would involve high-resolution CT scans on a large population,which needs a lot of resources,” Dr Salvi said. Citing anecdotal evidence,he said,“It is more common in middle-aged and senior people. We also see it more commonly among women than men.”