Dermatologist Explains Why Simple 'Glass Test' May Save a Child's Life

A board-certified dermatologist has won praise online after sharing the trick to test if a child's rash is a sign of severe infection, and it has the potential to be lifesaving.

Dr. Abigail Waldman is the clinical director of the Mohs and Dermatologic Surgery Center, located at the Brigham and Women's Hospital in Boston, and she took to social media to alert people to the simple "glass test" idea, which could "save your kid's life."

In a video posted on her TikTok account (@drabby6), Waldman explained that pressing a clear glass against a newly formed rash can detect bacterial meningitis. Speaking to Newsweek after sharing the trick, Waldman said: "I think any tool that can help to identify medically urgent illness is appreciated by parents everywhere."

In most cases, when the glass is held onto the skin the rash will fade, but Waldman, who is also an assistant professor of dermatology at Harvard Medical School, explained that when the rash remains a pink or red color under the glass, it can indicate something far more dangerous.

"The glass test involves taking a basic clear water glass, like one would have in the kitchen cabinet, and pressing it firmly against the rash. The rash should fade to look like normal skin color," Waldman told Newsweek.

"If it doesn't disappear and remains dark pink, red, or purple, this can be a sign that the blood vessels of the skin are affected and can be a red flag if the patient is also sick with a fever, lethargy, blood in urine, severe headache, nausea. The petechial rash associated with bacterial meningitis will present this way. Other dangerous rashes, associated sepsis, as well as inflammation of the blood vessels, can also fail the glass test."

Bacterial meningitis is a potentially fatal infection which causes swelling of the protective membranes covering the brain and spinal cord. The germs which spread bacterial meningitis can be ingested through food, but the Centers for Disease Control and Prevention (CDC) adds that most of the time it is spread from one person to another.

In general, symptoms will occur within three to seven days of exposure, with cases often displaying a fever, headache, stiff neck, nausea, sensitivity to light, and confusion.

Despite vaccinations greatly reducing the death rate of bacterial meningitis in recent years, it still remains a global health concern. The World Health Organization (WHO) estimates that one in every six people who contract the infection will die as a result, while one in five will develop severe complications.

It is vital to catch the infection early, and if there are any concerns for an individual's health, urgently seeking medical help is vital.

The glass test can be work on any skin tone, as the rash should fade to the person's normal skin color beneath the glass, and it can also work on adults to diagnose septicemia associated meningitis, according to Waldman.

What Was the Social Media Reaction?

After sharing the video on her TikTok account, Dr. Waldman was amazed by the positive reaction she received. In just one week, the video has already been viewed more than 3.6 million times and received over 210,000 likes, as many people praised her for sharing the noteworthy tip.

Waldman continued: "Many parents across the world have used it to diagnose children and save lives. As dermatologists, we use this test to identify dangerous rashes, but we use a glass slide or finger to perform the test instead of a water glass.

"It's a sensitive test in a sick child with a new rash. In a well child, or a child that is getting chemotherapy, or has other cause of low platelets, it's less foolproof since low platelets can cause bleeding into what otherwise would be a normal rash. It's also less sensitive in adults who are more likely to be on blood thinning medication."

The glass test can be done anywhere on the body, but is less sensitive on the lower legs, as Waldman explained that blood can collect due to gravity and mean that a rash may not blanche in that region.

The trick may only involve holding the glass on the skin for approximately five seconds, but Dr. Waldman said it is not a well-known practice. However, by sharing it on social media and spreading the word, she hopes it can potentially save lives in the future, as it has done in the past.

With more than 400 comments on the TikTok post so far, many people have praised the useful insight, and some have shared their own experiences of using the test.

One comment reads: "This saved my life as a child because my mother knew what to do. Thank you for spreading awareness."

Another person wrote: "Glass test saved me! Was down to 1 platelet by the time I got to the ER."

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