The digestive tract - from the stomach, the large and small intestines, and the liver, are where the food we eat is broken down, nutrients and minerals absorbed into the body, and the waste filtered out. In particular, the intestines - both small and large - are primarily involved in nutrition and water and electrolyte balance. In addition the intestines also play an important role in developing the body’s immunity.
Inflammatory Bowel Diseases such as Crohn’s Disease, Ulcerative Colitis, and other diseases such as colorectal cancer, are on the rise in India. While a study says that incidence of colorectal cancer is low, survival rates of those who develop the cancer is very low - with average survival being five years.
In India, there are public debates and discussions over heart diseases, about cancer, about other health risks, but very rarely do we talk about diseases of the digestive tract. In a country with a large burden of infectious diseases, especially water borne diseases, and with a high prevalence of malnourishment among children, we need a better understanding of all the issues surrounding the bowels, with greater awareness of methods to avoid disease and treat chronic conditions.
Professor Dr. Anil Vaidya, a Transplant Surgeon at Apollo Hospitals, Chennai, has been studying this for a while. He specialises in the rehabilitation of failing intestines as well as transplant of organs of the digestive tract, mainly the pancreas, and the intestines. At Apollo, he brings in new techniques and treatments methods for long-term intestinal health.
"The thing is, if a person has intestinal failure and no external support by artificial feeding and/or intravenous fluids, they will die within fifteen days," warns Dr Vaidya. "The only way for a person to survive if their intestine fails is if they are being given fluids and nutrients intravenously. This process is called TPN - Total Parenteral Nutrition."
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Because the small intestines have lost the ability to absorb nutrients from the food one eats, nutrients, the electrolytes, and the water - in absorbable forms - must be injected directly into the bloodstream. This is a first-line treatment option, but it has its risks. Because the body’s immune system is generated in the intestines, from the food we eat, TPN could lead to a reduction in natural immunity, and to increase in systemic infections. Electrolyte imbalances can also occur, and if left unchecked for a long time, this could affect other organs such as the liver and the kidney. Because TPN requires venous access, long term TPN may result in problems like thrombosis or scelerosis of the veins - and will need to be carefully managed through the patient’s lifetime.
But most importantly, TPN is an expensive procedure. The average cost is between Rs. 3500 and Rs. 8000 per day. "The problem in India is, TPN is not yet mature," says Dr Vaidya. He estimates, based on figures availabe in the western nations, that about 19 patients, per million, per year, may require some form of TPN.
Further, there are three 'types' of intestinal failure. Type 1 happens inside a hospital, where the bowels ‘fail’ (medically called ileus) in the course of major abdominal surgery. “50% of Type 1 patients recover with TPN,” says Dr Vaidya.
The 50% that don't recover go into Type 2 intestinal failure, where the patient may require 3 to 6 months of TPN and a multi-disciplinary team to take care of them in a specialised centre. 10% of these patients will go to Type 3, which is irreversible intestinal failure. They need TPN for the rest of their lives.
About 10% of the Type 3 patients may have complications from TPN. These complications qualify the patients for an intestinal transplant, says Dr. Vaidya.
Intestinal Transplantation, for long-term relief
"In the US, there are intestinal transplant programmes that are very mature. India is still way behind on that front," says Dr Vaidya.
Transplantation of the intestine is a definitive cure for chronic diseases such as Crohn’s. Dr Vaidya has in fact been instrumental in coming up with a scoring system for patients with Crohn’s disease to ascertain when would be the right time to transplant these patients. This article was published in a prestigious journal-JAMA Surgery.
Today, better surgical procedures and systems, and more sophisticated immunosupression drugs, are helping bring about better patient outcomes after intestinal transplantation. However, the expertise of the doctor performing the surgery, and the availability of donor organs, are factors to be considered. At Apollo Hospitals, Dr. Vaidya knows the risks, and the benefits, and advices his patients fully and thoroughly, in order to arrive at the informed, well-judged consent.
There are three types of intestinal transplant, explains Dr Anil Vaidya.
The first is an 'Isolated Intestinal Transplant', where only the intestine of the patient is not working or is absent due to a congenital problem or has been taken out during surgery for Crohn’s, or ischemia due to a blood clot. Here the stomach and the liver are fully functional. Thus only the intestines from a multi-organ cadaveric donor, is needed to create continuity of the patient’s bowels.
The second kind of transplant is called the Modified Multivisceral Transplant, where along with the intestine, some of the other organs in the digestive tract have also failed, but the liver is functioning.
The third kind is the true Multivisceral Transplant, where all the organs in the digestive system are transplanted simultaneously.
Evolution in Transplant procedures
“Intestinal transplantation has been around for 27 years,” says Dr. Vaidya. “ ‘And the immunology is fascinating! On the one hand, you have the inner lining which has bugs, and the outer cells with the body’s immunity. And now you’re taking this - physically taking it out, cooling it, and and placing it in someone else! It didn’t make any sense, till we actually did it”.
Dr. Vaidya, who has been there right at the beginning, has seen it evolve. The early thinking was one would need extra strong immunosuppression for the transplant to work. “And we were completely wrong!” says Dr. Vaidya. “And that evolution took 20 years.”
Studies in the US has showed that modern multivisceral transplant procedures have translated to better quality of life for patients, and that long-term, disease free survival rates have gone up since the 1990s.
“This is a paradox in transplantation. The more immune cells you transplant, there’s a switch off mechanism in the body. It says, ‘don’t attack it. It has to be friends, it cannot be such a big enemy’. So you need very little immunosuppression,” says Dr. Vaidya.
For intestinal transplantation, doctors these days give only one immunosuppression drugs, but for other organs, such as the kidney or liver, doctors may give 2 or 3 or more drugs to allow the body to “accept” the graft.
Dr. Vaidya has his own system to determine the effectiveness of these transplant procedures.
He creates a table with two columns - Easy, technically. Hard, immunologically. And he measures each of the transplant techniques against it.
The Isolated Transplant is easy to perform, but very hard in terms of its immunological impact.
The Modified Multivisceral transplant is not as easy a technique as isolated transplant, but has better immunological results. The Multivisceral Transplant is the easiest procedure, and has the best immunology, because the liver protects the other organs too.
“This has evolved to its very best in the west,” says Dr. Vaidya. India will need to catch up. But, with doctors like Anil Vaidya, and the Apollo Hospitals network, procedures and system will soon catch up to the rest of the world.