A 72 year old man in Guntur got a knee replacement in June 2025. Within a month, the artificial joint was infected by Pseudomonas aeruginosa, a bacterium resistant to a wide range of antibiotics, including carbapenems.
Months of washouts, a spacer exchange, an arthroscopy and weeks of intravenous antibiotics followed. By Dec, his pain was 9/10. The infection kept returning. Doctors judged further surgery unsuitable given his age and condition.
The team then tried bacteriophages: viruses that infect specific bacteria.
For those interested in the science, this is where the work gets interesting....
Dr Sutharsan Govindarajan's phage lab at SRM University-AP tested the patient's own bacterial isolate against a panel of phages. 3 were selected and genome-sequenced.
In lab tests, each phage alone initially killed bacteria, but this strain subsequently regrew. The 3 phage cocktail suppressed that regrowth.
The cocktail was delivered into the infected knee through a drainage tube over 10 days. The antibiotic colistin was given alongside from day 2. Lab tests had shown that the combination worked better against this strain than either treatment alone.
- On day 6, colistin was stopped after kidney function worsened. The phage treatment continued.
- By day 10, tests of the joint fluid no longer detected the resistant bacterium. Pain had fallen from 9 to 2-3, and the man could walk independently again. His inflammation marker returned to normal a few days after treatment ended.
- At 6 months, he remained antibiotic-free with no recurrence reported. A joint-fluid culture in June 2026 showed no growth of the pathogen.
The clinical team was led by Dr Kalyan Chakravarthy Koganti at Samishta Hospital (SHRI), Guntur. The authors describe this as, to their knowledge, India's 1st reported successful phage treatment of a carbapenem-resistant prosthetic joint infection.
Bharat is rising. 🙏🙏
Source: B. Sivaraj et al., "Adjunctive Phage Therapy for Carbapenem-Resistant Pseudomonas aeruginosa (CRPA) Prosthetic Knee Joint Infection in India: A Case Report", IJID Regions (2026), available online 14 October. DOI: 10.1016/j.ijregi.2026.101047.
Photo 1: Dr Kalyan Chakravarthy Koganti and the research team. (Credit: T. Vijaya Kumar / The Hindu.)
Photo 2: The actual paper's figure, including the patient's before/after knee photos, antibiotic-resistance results and recovery timeline. via Sivaraj et al., IJID Regions (2026), DOI: 10.1016/j.ijregi.2026.101047.