Antibiotic-resistant infections more deadly and costly, major Indian study finds
text_fields
Infections caused by carbapenem-resistant gram-negative bacteria are more likely to be fatal and more expensive to treat than infections caused by susceptible strains.
A major study across 20 tertiary-care hospitals in India conducted by researchers from the Indian Council of Medical Research’s antimicrobial resistance surveillance network between April 2022 and April 2025, analysed 159,336 hospitalised patients. Of these, 26,213 had confirmed infections caused by four major gram-negative bacteria: Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa.
Some 16,025 patients, or 61.1%, had carbapenem-resistant infections.
Mortality was higher for resistant infections across all four bacteria. Deaths among patients with resistant infections were 24.4% for E. coli, 31.2% for K. pneumoniae, 37.9% for A. baumannii and 28.9% for P. aeruginosa, compared with 17.3%, 23.5%, 32.8% and 20.2%, respectively, among patients with susceptible infections.
The differences were even more pronounced in bloodstream infections. Mortality among patients with resistant bloodstream infections ranged from 39.3% for E. coli to 50.8% for A. baumannii. More than 85% of bloodstream infections involving the four bacteria were healthcare-associated.
Treatment was also more expensive. Antibiotic costs for resistant infections were about 1.1 to two times higher than for susceptible infections, depending on the bacteria. For instance, treatment of resistant E. coli infections cost about ₹39,846 per patient, compared with ₹20,034 for susceptible infections. The figures cover only antibiotics and use national JanAushadhi rates, meaning actual costs could be higher.
The researchers said carbapenem resistance leaves doctors with fewer effective treatment options. Ceftazidime-avibactam was used more frequently than polymyxin-based treatment for some resistant infections and was associated with lower mortality in certain bloodstream infections, but the study could not establish that it is universally superior.
Most infections were healthcare-associated, with rates ranging from 85% for E. coli to 95.1% for A. baumannii. Recent surgery and the use of luminal medical devices were also more common among patients with resistant infections.
The researchers called for stronger antimicrobial stewardship, better infection prevention and control, faster diagnostics and improved access to effective treatments.
They cautioned that the findings, largely drawn from tertiary hospitals treating referred and critically ill patients, should not be interpreted as measures of hospital performance.