Importance of Microbiomes on skin: post surgical infections (Introduction)

by David Turell , Sunday, April 14, 2024, 17:05 (221 days ago) @ David Turell

A careful study of skin bacteria in surgical patients:

https://www.sciencealert.com/scientists-reveal-where-most-hospital-infections-actually-...

"Genetic data from the bacteria causing these infections – think CSI for E. coli – tells another story: Most health care-associated infections are caused by previously harmless bacteria that patients already had on their bodies before they even entered the hospital.

"Research comparing bacteria in the microbiome – those colonizing our noses, skin and other areas of the body – with the bacteria that cause pneumonia, diarrhea, bloodstream infections and surgical site infections shows that the bacteria living innocuously on our own bodies when we're healthy are most often responsible for these bad infections when we're sick.

"Our newly published research in Science Translational Medicine adds to the growing number of studies supporting this idea. We show that many surgical site infections after spinal surgery are caused by microbes that are already on the patient's skin.

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"In our work as clinicians at Harborview Medical Center at the University of Washington we've seen how hospitals go to extraordinary lengths to prevent these infections. These include sterilizing all surgical equipment, using ultraviolet light to clean the operating room, following strict protocols for surgical attire and monitoring airflow within the operating room.

"Still, surgical site infections occur following about 1 in 30 procedures, typically with no explanation. While rates of many other medical complications have shown steady improvement over time, data from the Agency for Healthcare Research and Quality and the Centers for Disease Control and Prevention show that the problem of surgical site infection is not getting better.

"In fact, because administering antibiotics during surgery is a cornerstone of infection prevention, the global rise of antibiotic resistance is forecast to increase infection rates following surgery.

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"Over a one-year period, we sampled the bacteria living in the nose, skin and stool of over 200 patients before surgery. We then followed this group for 90 days to compare those samples with any infections that later occurred.

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"Our results revealed that while the species of bacteria living on the back skin of patients vary remarkably between people, there are some clear patterns. Bacteria colonizing the upper back around the neck and shoulders are more similar to those in the nose; those normally present on the lower back are more similar to those in the gut and stool. The relative frequency of their presence in these skin regions closely mirrors how often they show up in infections after surgery on those same specific regions of the spine.

"In fact, 86 percent of the bacteria causing infections after spine surgery were genetically matched to bacteria a patient carried before surgery. That number is remarkably close to estimates from earlier studies using older genetic techniques focused on Staphylococcus aureus.

"Nearly 60 percent of infections were also resistant to the preventive antibiotic administered during surgery, the antiseptic used to clean the skin before incision or both.

"It turns out the source of this antibiotic resistance was also not acquired in the hospital but from microbes the patient had already been living with unknowingly. They likely acquired these antibiotic-resistant microbes through prior antibiotic exposure, consumer products or routine community contact."

Comment: our microbiome thread about the skin shows the bugs are friendly until the skin is sliced. I can imagine the scalpel blade bringing in the previously friendly bugs as it slices deeper. Back to theodicy: the infections occur, not because the bacteria are 'bad', but they are freely built to survive on any food available. Not God's fault. Bacteria necessarily live as freely-acting organisms.