A Harvard study solves the mystery of the causes of constant itching!

Scientists have long believed that persistent itching in people with skin conditions such as eczema was due to inflammation.

But for the first time, scientists have shown that the itching associated with eczema may be caused by a completely different mechanism.

In a first-of-its-kind study on mice and human cells, the Harvard research team found that a strain of normally harmless bacteria that lives in people's noses and skin can invade skin cells and cause an uncontrollable urge to scratch.

“We have identified an entirely new mechanism behind itching: Staph aureus bacteria, which are found in almost every patient with a chronic case of dermatitis,” said Dr. Isaac Chiu, study author and professor of immunology at Harvard Medical School. 

These findings could inspire new topical treatments to stop chronic itching in people with eczema and other conditions.

In patients with eczema, the balance of the skin's microbiome, or healthy bacteria, and the oils that protect it are thrown out, allowing harmful bacteria to spread.

This includes Staphylococcus aureus, which is usually found on the skin or in the nose and is usually harmless. It may cause skin infections, food poisoning, and bacteremia.

They then exposed the mice to Staphylococcus aureus, which caused them to develop severe itching that worsened over several days and led to skin damage.

The team modified different versions of the microbe Staphylococcus aureus to find the enzymes responsible for the itch. The bacteria usually invade the skin and release 10 different enzymes.

The researchers said that an enzyme called V8, which works like molecular scissors, cuts part of the PAR1 protein that lines nerve cells in the skin, which causes PAR1 to release a signal through the skin nerve cells and even the brain, and thus the desire to scratch.

The team also found that inflammatory white blood cells, which are activated in skin conditions such as eczema and other allergies, do not lead to itching.

“When we started the study, it wasn't clear whether itching was the result of inflammation or not,” said Dr. Liuyin Ding, the study's lead author and a postdoctoral researcher in Dr. Chiu's lab. “We showed that these things can be separated, and that you don't have to have inflammation.” "The microbe causes itching, but the itching exacerbates the inflammation on the skin."

PAR1 helps blood clot, so the researchers gave the itchy mice an FDA-approved anticoagulant to prevent PAR1 from starting the cascade reaction. The urge to scratch is greatly reduced, as is the skin damage caused by itching.

The researchers also plan to test whether other bacteria can trigger itching in patients with skin conditions.

The study was published in the journal Cell.

Researchers reveal who is most at risk of developing sepsis!

Being poor or having a pre-existing health condition increases the risk of sepsis, researchers said.

A history of widespread antibiotic exposure or learning disabilities also increases the risk for individuals.

Sepsis is a life-threatening condition where the body overreacts to an infection and begins attacking its own tissues and organs.

The latest research, led by a team from the University of Manchester, examined NHS data on 224,000 sepsis cases in England between January 2019 and June 2022.

It was found that people from the poorest communities were 80% more likely to develop sepsis than their counterparts in wealthier areas. The risk for people with learning difficulties was also much higher.

The same applies to victims of chronic liver and kidney diseases. Higher risks were observed in relation to cancer, diabetes, smoking and weight problems.

Professor Tjeerd van Staa, co-author of the research, said: “This research underscores the urgent need for sepsis risk prediction models to take into account chronic disease status, deprivation status, learning difficulties, as well as infection severity.”

There is an urgent need to improve sepsis prevention, including more precisely targeting antimicrobials to patients most at risk.

In adults, sepsis may look like the flu, gastroenteritis, or chest infection at first. Early symptoms include fever, chills, shivering, rapid heartbeat, and rapid breathing.

The Manchester study was published in the journal eClinicalMedicine.