My new story for the Medical Post/Canadian Healthcare Network. #Doctors and #pharmacists in Canada can log on for free. Here are a few paragraphs.
Could a century old treatment be an answer to antibiotic resistance?
In a first in Canada, a patient with an #antibiotic resistant artificial joint infection has received treatment with phage therapy and is showing promising early responses.
“This is cutting edge stuff, and a potentially new technology,” said Dr. Marisa Azad, the infectious diseases physician who treated the patient. She is also an assistant professor of medicine at the University of Ottawa.
The patient presented with severe periprosthetic joint infection (PJI) in the summer of 2023. She had already undergone multiple surgeries and had experienced several relapses and infections with the same persistent bacteria.
“She’d been on multiple very prolonged courses of antibiotics and had a severe drug allergy to two major drug classes of antibiotics. I was extremely limited in what I could use to treat her,” Dr. Azad told the Medical Post in an interview.
That’s when the idea arose of trying an experimental treatment course with phage therapy. The team got approval for doing the experimental treatment from Health Canada, and worked with Winnipeg-based Cytophage, which supplied the phages.
“We developed a protocol and gave her therapy over two weeks while she was admitted to hospital. She’s completed her therapy. Now we’re monitoring her closely and giving her adjunctive antibiotics,” she said.
The idea didn’t come out of the blue. In the medical literature, a study from just last year in Clinical #Infectious Diseases provided a review of 33 previously published cases of patients with end-stage, refractory bone and joint infections (BJI) who underwent treatment with phage therapy. The authors found that from those case reports, “29 (87%) achieved microbiological or clinical success, two (5.9%) relapsed with the same organisms, and two (5.9%) with a different organism” with no serious adverse events.
The conclusions of that paper stated there were “important advantages, disadvantages, and barriers to the implementation of phage therapy for BJIs.” Yet, at the same time, the authors added they, “believe that if phage therapy were to be used earlier in the clinical course, fewer cumulative antibiotics may be needed in an individual treatment course.”
The word phage is short for #bacteriophage, a word coined in 1917—literally meaning bacteria-eater. They are viruses whose lifecycle depends on certain types of bacteria.
“They latch on to specific types of bacteria and inject their genetic material into the bacterial cell." Dr. Azad explained. "They take over the bacterial cells’ machinery to produce more little viruses inside and explode or burst open the bacteria,” releasing viral particles that can go and infect other cells of the same type of bacteria.
Intriguingly, each #phage targets a specific type of #bacteria...
The story of phages started over 100 years ago. They were independently discovered, first in 1915 by a British pathologist, Frederick Twort, and then again in 1917 by French-Canadian microbiologist Felix d’Herelle. And...
The tail tips, the most diversified region across #bacteriophage lambda & other long-tailed #phages, contain conserved domains which facilitate tail assembly, receptor binding, cell adsorption and DNA retention/release #PLOSBiologyhttps://plos.io/3Rqs6nI
Impressive depiction of a #bacteriophage launching an assault on a bacterial cell. Bacteriophages, resembling creatures from a science fiction thriller, are specialized #viruses that target and infect bacterial cells by binding to specific surface proteins. They inject their #genetic material to hijack the bacterial machinery for replication, ultimately leading to the demise of the bacterial #cell.
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"Identification and genomic analysis of temperate Halomonas bacteriophage vB_HmeY_H4907 from the surface sediment of the Mariana Trench at a depth of 8,900 m", Su et al. 2023 https://pubmed.ncbi.nlm.nih.gov/37728551/
No corner of this planet without viruses – unsurprisingly.