Posts tagged with "Studies"

UW team devises first smartphone app that can ‘hear’ ear infections in children

May 17, 2019

Ear infections send more children to the pediatrician than any other ailment, according to the National Institutes of Health.

Even the youngest child may pull or tug at his or her ear when pressure and pain start to build up inside. This condition, usually caused by a bacterial infection, occurs when fluid gets trapped in the middle ear behind the eardrum. The same type of problem also is common in another condition called otitis media with effusion—where the infection is gone, but the fluid has not drained.

Any kind of fluid buildup in the ears can hurt and make it hard for children to hear, which is especially detrimental when they are learning to talk.

But now, researchers at the University of Washington have created a new smartphone app that can detect fluid behind the eardrum, when used along with three easily available aids: a piece of paper and the smartphone’s microphone and speaker.

The smartphone makes a series of soft audible chirps into the ear through a small paper funnel and—depending on the way the chirps rebound to the phone—the app determines the likelihood of fluid present with a probability of detection of 85% (similar to the results achieved with more sophisticated processes used currently, including acoustics and puffs of air).

When there is no fluid behind the eardrum, the eardrum vibrates and sends a variety of sound waves back. These sound waves mildly interfere with the original chirp, creating a broad, shallow dip in the overall signal. But when the eardrum has fluid behind it, it doesn’t vibrate as well and reflects the original sound waves back. They interfere more strongly with the original chirp and create a narrow, deep dip in the signal.

 “Designing an accurate screening tool on something as ubiquitous as a smartphone can be game-changing for parents as well as healthcare providers in resource-limited regions,” said co-author Shyam Gollakota, an associate professor in the UW’s Paul G. Allen School of Computer Science & Engineering. “A key advantage of our technology is that it does not require any additional hardware other than a piece of paper and a software app running on the smartphone.”

A quick screening at home could help parents decide whether or not they need to take their child to the doctor.

“It’s like tapping a wine glass,” said co-first author Justin Chan, a doctoral student at the Allen School. “Depending on how much liquid is in [the ear], you get different sounds. Using machine learning on these sounds, we can detect the presence of liquid.”

To train an algorithm that detects changes in the signal and classifies ears as having fluid or not, the team tested 53 children between the ages of 18 months and 17 years at Seattle Children’s Hospital. About half of the children were scheduled to undergo surgery for ear tube placement, a common surgery for patients with chronic or recurrent incidents of ear fluid. The other half were scheduled to undergo a different surgery unrelated to their ears, such as a tonsillectomy.

Among the children getting their ear tubes placed, surgery revealed that 24 ears had fluid behind the eardrum, while 24 ears did not. For children scheduled for other surgeries, two ears had bulging eardrums characteristic of an ear infection, while the other 48 ears were fine. The algorithm correctly identified the likelihood of fluid 85% of the time, which is comparable to current methods that specialized doctors use to diagnose fluid in the middle ear.

Then the team tested the algorithm on 15 ears belonging to younger children between 9 and 18 months of age. It correctly classified all five ears that were positive for fluid—as well as nine out of the ten ears, or 90%, that did not have fluid.

“Even though our algorithm was trained on older kids, it still works well for this age group,” said co-author Dr. Randall Bly, an assistant professor of otolaryngology at the UW School of Medicine who practices at Seattle Children’s Hospital. “This is critical because this group has a high incidence of ear infections.”

Because the researchers want parents to be able to use this technology at home, the team trained parents how to use the system on their own children. Parents and doctors folded paper funnels, tested 25 ears and compared the results. Both parents and doctors successfully detected the six fluid-filled ears. Parents and doctors also agreed on 18 out of the 19 ears with no fluid. In addition, the sound wave curves generated by both parent and doctor tests looked similar.

Rajalakshmi Nandakumar, a doctoral student in the Allen School, is also a co-author on this paper. This research was funded by the National Science Foundation, the National Institutes of Health and the Seattle Children’s Sie-Hatsukami Research Endowment.

The team published its results on May 15 in the journal, Science Translational Medicine.

Research contact: earhealth@uw.edu.

Take a chill pill: You actually may not be allergic to penicillin

February 1, 2019

Penicillin was the original “wonder drug”—but, today, people are wondering why, for more than half a century, doctors have warned them it’s contraindicated for their care.

Discovered in 1928 and found to “miraculously” cure infections by 1942, penicillin was the first antibiotic that many Baby Boomers were prescribed as children. However, that first dose of penicillin also turned out to be the last for many youngsters—who broke out in bumps or rashes that were diagnosed as allergic reactions.

Now there is a different school of thought. In fact, according to a study posted by the Journal of the American Medical Association in January, fully 19 out of 20 people who have been told they are allergic to penicillin actually can tolerate it well.

Indeed, The New York Times reported on January 22, millions of Americans whose medical histories document their penicillin sensitivities are not actually allergic. But they are steered away from using some of the safest, most effective antibiotics—relying instead on substitutes that are often pricier, less effective, and more likely to cause complications such as antibiotic-resistant infections.

Experts in allergy and infectious disease, including the paper’s authors, are now urging patients to ask doctors to review their medical history and re-evaluate whether they truly have a penicillin allergy.

The evaluation—which may require allergy skin testing and ideally should be done while people are healthy— is especially important, The Times reports, for pregnant women, people with cancer and those in long-term care, and anyone anticipating surgery or being treated for a sexually transmitted infection.

“When you have a true infection that needs to be treated, the physician will see you have the allergy and not question it,” said  Dr. Erica S. Shenoy, an author of  the study, and an infectious diseases specialist who is s on the staff of Harvard Medical School of Massachusetts General Hospital.

The review was carried out with input from the boards of three professional medical organizations: the American Academy of Allergy, Asthma and Immunology; the Infectious Diseases Society of America; and the Society for Healthcare Epidemiology of America. All three groups endorsed the findings.

There is no question that some patients have potentially life-threatening allergic reactions to penicillin, but the label appears to have been applied far too broadly, experts say. About 10% of Americans report having a penicillin allergy, and the rate is even higher among older people and hospital patients—15% of whom have a documented penicillin allergy.

But studies that have gone back and conducted allergy skin testing on patients whose medical records list a penicillin allergy have found that the overwhelming majority test negative. A 2017 review of two dozen studies of hospitalized patients found that over all, 95 percent tested negative for penicillin-specific immunoglobulin E, or IgE, antibodies, a sign of true allergy.

 “We used to say nine out of 10 people who report a penicillin allergy are skin-test negative. Now it looks more like 19 out of 20,” Dr. David Lang, president-elect of the American Academy of Allergy, Asthma and Immunology and chairman of allergy and immunology in the respiratory institute at the Cleveland Clinic, told the Times.

What’s more, the researchers say, many people who have avoided penicillin for a decade or more after a true, severe allergic reaction will not experience that reaction again.

“Even for those with true allergy, it can wane,” said Dr. Kimberly Blumenthal, the review’s senior author, who is an allergist and an assistant professor at Harvard Medical School. “We don’t really understand this, but once you’ve proven you’re tolerant, you go back to having the same risk as someone who never had an allergy” to penicillin.

Finally, the researchers warn, don’t challenge yourself to penicillin on your own. Patients who have been told they’re allergic to penicillin should talk to their doctors, who should take a careful history and review the symptoms of the reaction.

If the past reaction to penicillin included symptoms like headache, nausea, vomiting and itching, or the diagnosis was made based on a family history of the allergy, the patient is considered low-risk and may be able to take a first dose of penicillin or a related antibiotic, such as amoxicillin, under medical observation.

If the past reaction included hives, a rash, swelling, or shortness of breath, patients should have penicillin skin test, followed by a second test that places the reagent under the skin if the first test is negative. If both tests are negative, the patient is unlikely to be allergic to penicillin, and an oral dose may be given under observation to confirm

Research contact:  @nytimes