Mumbai: Drug-resistant bacterial infections are associated with significantly higher mortality and treatment costs than infections caused by drug-sensitive strains, a new Indian Council of Medical Research (ICMR) study involving 20 tertiary-care hospitals has found.
Published in The Lancet Regional Health–Southeast Asia, the study analysed 1.6 lakh hospitalised patients between April 2022 and April 2025, including patients at Hinduja Hospital in Mahim. Of these, 26,213 had infections caused by four major Gram-negative bacteria—E coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa.
A worrying 61.1% of these infections were carbapenem-resistant. Carbapenems were, until a few years ago, considered last-resort antibiotics for some of the most serious infections but are being used more frequently these days.
“Antimicrobial resistance is no longer a distant threat—it is already costing Indian lives,” said senior scientist from ICMR, Dr Kamini Walia, an author of the study. “Our study shows that carbapenem-resistant infections carry substantially higher mortality and treatment costs,” she said, adding that the answer is not simply more powerful antibiotics, but “better infection prevention, timely diagnostics and responsible antibiotic use”.
The study compared mortality among patients with resistant and susceptible forms of the same bacteria. Mortality was 31.2% among those with resistant K pneumoniae, compared with 23.5% among those with susceptible infections. The corresponding figures were 24.4% versus 17.3% for E coli; 37.9% versus 32.8% for A baumannii; and 28.9% versus 20.2% for P aeruginosa.
Treatment was also more expensive for resistant infections. “Antibiotic treatment costs were 1.1–2 folds higher for resistant infections,” said the study. The average cost for resistant E coli was $420 per patient, compared with $211 for susceptible infections. For K pneumoniae, the costs were $587 and $505; for A baumannii, $655 and $436; and for P aeruginosa, $702 and $510.
Resistant infections were also associated with longer hospital stays. Patients with resistant E coli, for instance, stayed an average 23.1 days, compared with 17.8 days for those with susceptible infections.
Dr Rahul Pandit, critical care specialist at H N Reliance Hospital in Girgaum, said Mumbai hospitals were seeing an increasing number of patients with carbapenem-resistant infections.
“It takes longer to treat a patient with a drug-resistant infection. Developing a culture, identifying the organism and determining its resistance pattern can take a few days, although molecular diagnostics can help us do this faster,” said Pandit, who was not associated with the study.
Patients with drug-resistant infections may also require combinations of antibiotics, he said, thereby increasing the cost of treatment. With home-care services increasingly available, some patients who do not require prolonged hospitalisation can receive injectable antibiotics at home under nursing supervision, he added.
The researchers, however, cautioned that the study was conducted in tertiary hospitals, where critically ill and referred patients are more likely to be treated, and therefore the findings should not be interpreted as indicators of individual hospital performance.
The findings underline the need for stronger antimicrobial-resistance surveillance, infection-control measures, antimicrobial stewardship and timely access to effective drugs, they added.
