Scientists Use Phage Therapy Against Resistant Joint Infection in Guntur

Doctors at Samishta Hospital (SHRI) in Guntur treated a 72-year-old man with a carbapenem-resistant infection of an artificial knee joint using phage therapy. The case, published on 22 October 2026 in the International Journal of Infectious Diseases (IJID Regions), is India’s first reported successful use of phage therapy for a carbapenem-resistant artificial joint infection.

Phage Therapy and Bacteriophages

Bacteriophages, or phages, are viruses that infect and replicate within bacteria. Many phages target particular bacterial species or strains, making identification of the infection-causing bacterium important when selecting a treatment. Lytic phages multiply inside bacterial cells and cause them to rupture. In the Guntur case, the infected knee joint contained Pseudomonas aeruginosa, a bacterium resistant to carbapenems and other antibiotics. Researchers at the phage laboratory of SRM University in Andhra Pradesh developed a cocktail containing three specific bacteriophages. The clinical team, led by Dr Kalyan Chakravarthy Koganti, delivered the cocktail directly into the infected joint over 10 days.

Drug Resistance and Joint Infections

Carbapenems are a class of broad-spectrum beta-lactam antibiotics used to treat serious bacterial infections. Carbapenem resistance can limit treatment options for infections caused by bacteria such as Pseudomonas aeruginosa. An infection involving an artificial joint is a form of prosthetic joint infection, which can be assessed through joint-fluid testing and bacterial culture. The patient’s artificial knee had become infected after surgery in June 2025. Follow-up tests in June 2026 found no infection in a joint-fluid culture; the patient remained healthy and antibiotic-free. In August 2025, SHRI Hospital doctors also treated a 72-year-old woman from Bapatla for a chronic bone and joint infection caused by multidrug-resistant Acinetobacter baumannii; she had no recurrence during six months of follow-up.

Clinical Cases and Exam Facts

Important Facts for Exams

• Bacteriophages are viruses that infect bacteria.
• Carbapenems belong to the beta-lactam class of antibiotics.
• The Guntur patient received a cocktail of three bacteriophages directly into the knee joint over 10 days.
• The Guntur findings appeared in International Journal of Infectious Diseases (IJID Regions).

The June 2026 follow-up culture showed no signs of infection in the patient’s joint fluid. The 2025 case involved Acinetobacter baumannii, a bacterium associated with multidrug-resistant infections.