A large Indian hospital study has found that infections caused by carbapenem-resistant Gram-negative bacteria were associated with higher mortality, longer hospital stays and greater antibiotic costs than infections caused by susceptible strains.
Scale of the research
The study involved 20 tertiary-care hospitals and analysed roughly 160,000 hospitalised patients between April 2022 and April 2025, according to reporting based on the published research. Among them, 26,213 patients had infections involving four major organisms: Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa.
The researchers were part of the Indian Council of Medical Research’s antimicrobial-resistance surveillance network. The paper was published in The Lancet Regional Health – Southeast Asia.
Mortality differences
Reported mortality for resistant K. pneumoniae infections was 31.2%, compared with 23.5% for susceptible infections. For E. coli, the figures were 24.4% and 17.3%; for A. baumannii, 37.9% and 32.8%; and for P. aeruginosa, 28.9% and 20.2%.
These are observed associations within the study population. They do not mean antibiotic resistance was the sole cause of every death, because patient age, illness severity and other conditions can also affect outcomes.
Costs and hospital stays
Antibiotic treatment costs were reported to be about 1.1 to two times higher for resistant infections, depending on the organism. Patients with resistant E. coli, for example, stayed an average of 23.1 days compared with 17.8 days for susceptible infections.
Longer admissions increase costs for families and hospitals while occupying beds that could serve other patients.
Why carbapenem resistance is serious
Carbapenems are important antibiotics used for severe bacterial infections. When bacteria resist them, clinicians have fewer treatment options and may need costlier drugs with more complex dosing or side-effect profiles.
The findings support stronger infection prevention, faster diagnostics and careful antibiotic use. They do not support patients stopping prescribed antibiotics or self-treating. Individual treatment decisions must be made by qualified clinicians using culture and susceptibility results where available.
What hospitals can do
Priorities include hand hygiene, environmental cleaning, isolation procedures, surveillance and antibiotic-stewardship programmes. Laboratories also need the capacity to identify organisms and resistance quickly.
The study gives Indian hospitals local evidence that resistance has measurable clinical and financial consequences, strengthening the case for prevention rather than relying only on new medicines.
