If you press your finger on the skin for a few seconds and release, does the skin lighten before returning to its normal color? This is called cleansing.
Several social media accounts post this test as a trick to parents that a child's result requires medical attention. But can this house cleaning test be used to determine if the rash is severe or not? That's what the experts say.
What is the skin flush test?"Pantheosis is a change in skin color when blood pressure increases from the affected area," Minnesota, MD, professor of dermatology and pediatrics at the Mayo Clinic in Rochester, told TODAY. "For example, if I put it on my skin ... and when I remove my finger, it looks a little pale ... that's because I've constricted or temporarily stopped blood flow to that area," adds Davis.
Medically, it's called "diascopy," Davis says, and involves taking an object glass and pressing it over the sore or red skin to determine what type of rash or injury is present, and when pressed, the color fades. . . .
Like Dr. Adam Friedman, a professor in the Department of Dermatology at the School of Medicine and Science, today you can do this at home with a cup that makes it easy to see the skin underneath where pressure is applied. . Washington. "Be careful with the pressure because you don't want to break the glass in the skin, I've seen it," Friedman says.
Why are some rashes "white" and others not?"The reason an area of the skin turns red is because the blood vessels dilate, or dilate, and more blood flows into that area," Friedman says. Therefore, a "faded" or "faded" rash occurs when the red color (erythema) or discoloration follows pressure, but reappears because the blood is still in the vessels and moving.
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If the rash doesn't fade, it means it won't disappear or go away when pressed, experts say. It's caused by bleeding or bleeding from damaged blood vessels under the skin (also called purpura), which can be caused by a variety of medical conditions, Friedman explains. "When the blood is outside the veins... it doesn't turn white (because) it can't be moved," he said.
It is important to note that the rash or color may vary on different skin tones. "Dark skin is harder to pick up and even detect erythema," says Friedman. "It might take more pressure ... to see that it's contagious," Friedman said.
What is a "white" ribbon?"Often people think that if something is bleached it's harmless, but that's not true, it can be dangerous," says Davis.
Excessive peeling can occur because of a lack of circulation, Davis says. "Blood vessels constrict due to pain or changes in temperature, causing the tips of the fingers and toes to turn white," says Davis.
Another common pale rash is caused by ruptured or enlarged blood vessels (also known as telangiectasia), which are usually healthy and harmless, Davis says. "However, there is a difference between what is pale or not and what is bad or harmful," he says, adding that sometimes telangiectasia can be a sign of a more serious underlying disease.
"In the early stages of vasculitis (inflammation of the blood vessels), which can be very painful, the lesions are often pale because there is not enough inflammation or destruction to allow blood to flow out," says Davis.
Allergic reactions and insect bites can cause a mild rash, Friedman explains. "If a person has itching or scarring related to a food or drug reaction ... it can be removed," Friedman says. Hives are usually harmless, he says, but when mixed with symptoms like wheezing or shortness of breath, they can cause an emergency.
"It all depends on what happens in the explosion," Friedman added.
According to Friedman, there is a very pale rash with systemic symptoms (such as fever, joint pain, organ failure, diarrhea, vomiting). "There are a number of life-threatening drug reactions with mild rash ... that you don't want to avoid," Friedman says.
Is the wound serious without blanching?According to Friedman, there are many causes of a "purpuric" rash, or bleeding under the skin, and some are more serious than others.
Bacterial meningitis can cause a rash that doesn't go away, Friedman says, as can other bacterial infections, such as meningococcal disease and gonococcal disease. "(They're) really systemic infections that are reflected in the skin because these bacteria are circulating in the bloodstream," Friedman said.
The purple rash, or vasculitis, can be caused by viruses such as hepatitis C, autoimmune diseases, and in some patients with compromised immune systems, Friedman explains.
"You don't see that (rash) in these cases, it's just ... the patient will have other symptoms," Friedman said, adding that this complication is relatively rare.
According to the Mayo Clinic, symptoms of meningitis include a high fever, stiff neck, severe headache, confusion and vomiting.
The appearance of a non-white rash can be a clue. "If you have palpable purpura, a rash that won't go away that you can feel, our mantra in Dermatology is vasculitis," says Friedman.
"Vasculitis is inflammation of the blood vessels, which means they are damaged or even destroyed," says Friedman, and can be caused by drug reactions and malignant disease (cancer). If you suspect a rash that won't go away is vasculitis, Friedman recommends seeing your doctor for an evaluation to determine the cause.
According to Friedman, some persistent rashes are harmless, and one of the most common is called benign purpura pigmentosa. Others are solar purpura, a large, purple rash that's more common in older people's sun-exposed areas, Friedman says, and blood vessels that have been damaged or ruptured by other activities. "They are aggressive but friendly," he added.
While not all outbreaks are sudden, "it's never bad to go ahead and clean it up," Friedman said, adding that people should be on the lookout for other symptoms. .
"If a patient has a rash that won't go away, they need to be more proactive in seeking medical attention," Davis said.
Can this test be used to determine the severity of the rash?The short answer is no: You can't tell whether a rash is healthy or serious just by its presence or absence, Davis says, adding that there are many factors that can tell the difference.
"Unfortunately, there are no hard and fast rules for distinguishing whether a rash is dangerous or not based on certain behaviors," he said.
While the bleach test can help determine the type of rash you have, it is not a diagnostic test.
"You want to be able to tell the difference between a rash and a rash, but given that there are a lot of other things that you have to avoid ... is it just a rash or is there something else?" Friedman said. . Both experts recommend looking for other signs and symptoms if you develop a rash.
One of them is fever. "I think a fever and rash should always get some kind of diagnosis, and a fever and rash that doesn't go away is more of a concern," Friedman says.
"If a child or adult is really sick, has a fever, or is very sick ... it requires emergency or emergency care," Davis said.
Another important thing to remember is how the rash spreads. "If the rash persists for no reason ... it could be more serious and you should see a doctor as soon as possible," says Davis.
"Anytime you have a rash, whether it's an adult or a child, it's important to know your overall health," says Davis. Because often the skin is a window to the general health of the body.
This article was originally published on TODAY.com.