After suffering severe abdominal pain for about a week, 40-year-old Santosh, who ekes out a living through farming and working as a labourer in a village in north-eastern Madhya Pradesh, at last decided to seek medical treatment.

That meant a 200-km journey to a small rural hospital in Bilaspur district in the neighbouring state of Chhattisgarh.

A bacterial infection had turned a part of his intestines gangrenous, said Yogesh Jain of the Jan Swasthya Sahyog that runs the 35-bed referral health centre near the village of Ganiyari.

The organisation is a voluntary, nonprofit one run by health professionals, which seeks to reach effective low-cost care to village and tribal people in an underdeveloped part of the country.

The pus collected from Santosh's abdomen during surgery revealed that the bacterium was resistant to most antibiotics, he told this correspondent.

Apart from surgery, Santosh had to be treated with an intravenous antibiotic that cost more than Rs. 33,000 for a 15-day course. If the bacterium had not been drug-resistant, the antibiotics for it would have cost just Rs. 780.

Big issue

Antibiotic resistance was, he said, a big issue that the health centre was coming up against in many sorts of infections.

Right from the time that the world's very first antibiotic, penicillin, became available in the 1940s, resistance has been a problem. Hitherto, as bacteria evolved ways to evade one drug, a newer one became available.

But with the rising tide of drug-resistance in bacteria, 'super-bugs' have emerged that are barely treatable. Few new antibiotics are being developed and many worry that the world is running out of ways to keep these organisms in check.

There is particular concern over what are known as Gram negative bacteria, a classification based on whether the germ can be stained in the laboratory using a specific technique for examination under a microscope.

Escherichia coli, a bacterium that is found in the gut, falls in this category. It spreads easily through faecal contamination of food and water. It is a common cause of urinary infections, and can also produce pneumonia and life-threatening bloodstream infections in hospitalised patients. Klebsiella pneumoniae, which is responsible for many dangerous hospital infections, too comes in this group.

Swapping genes

Fewer antibiotics are effective against Gram negative pathogens. In addition, with their ability to readily swap genes, these germs have become alarmingly resistant to many of those drugs. Disease-causing strains of E. coli, K. pneumoniae and other Gram-negative bacteria have emerged with genes for ‘extended spectrum beta-lactamases' (ESBLs).

These genes produce enzymes that make the bacteria immune to the effects of a wide range of antibiotics.

India has significantly higher levels of ESBL infections compared to other countries in the Asia-Pacific region, observed Balaji Veeraraghavan of the Department of Clinical Microbiology at the Christian Medical College in Vellore.

Elsewhere, such drug-resistant infections were typically picked up in hospitalised patients. But, in this country, community-acquired ESBL infections, particularly of E. coli, were at levels similar to that of hospital acquired ones.

The high level of ESBL-producing E. coli reflects poor standards of hygiene as well as inappropriate use of antibiotics, he added. Even when the right antibiotic was used, it was often given at too low a dose.

ESBL positive

By last year, at least a quarter of the E. coli isolated from patients who came to the Ganiyari health centre with community-acquired urinary tract infections were ESBL positive, remarked Biswaroop Chatterjee, a medical microbiologist who worked with the Jan Swasthya Sahyog for several years and left in 2010. With hospital-acquired infections, the proportion could be over 50 per cent.

Antibiotics known as carbapenems are needed to treat many ESBL infections. The result has been that bacteria have evolved ways to evade these drugs too.

The first Klebsiella pneumoniae carbapenemase was reported in the U.S. in 1996. Such highly drug-resistant forms of Klebsiella have now reached countries across the globe.

Creating an uproar

Last year, the spread of another form of carbapenem resistance created an uproar. Several countries found that people who returned after medical treatment in India and other South Asian countries were carrying bacteria that had the New Delhi metallo-beta-lactamase-1 (NDM-1) gene.

A signficant number of cases of NDM-1-producing E. coli had been identified, which suggests this resistance was being disseminated in the environment as well as in hospitals, observed Patrice Nordmann and others in a journal paper published earlier this year.

As of now, NDM-1-producing bacteria appeared to be a hospital-acquired infection, said Dr. Balaji. Carbapenem-resistant bacteria like those with the NDM-1 gene could be treated only with a new drug called tigecycline and an old one known as colistin. The latter had to be administered only with close supervision of the patient, watching for any signs that it might be damaging the kidneys.

If such highly resistant bacteria started spreading in the community, as was happening with ESBL producing ones, it will create a “very dangerous situation,” he remarked.


Tackling drug resistanceApril 7, 2011

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