Kristy Gilmer Knight, M.S., a pediatric audiologist at OHSU's Doernbecher Children's Hospital says, "The purpose of the study is to make people aware that this is more common than people think and we need to follow this issue."

Researchers agree a major problem for doctors trying to diagnose hearing loss stemming from a toxin or medication is that it's not that obvious.

Ototoxicity, the focus of the study, is defined as damage of the ear, specifically the cochlea or auditory nerve and sometimes the vestibulum, usually by a toxin or medication.

Knight says, "The way it manifests itself is tricky. The typical presentation is high-frequency hearing loss, and so it may not look like they're having a problem, especially when communicating one-on-one in a quiet room. And kids won't complain about not understanding what was said when they're really little."

According to the study, hearing loss was found in 61 percent of patients, with average onset beginning 135 days after chemotherapy.

However, researchers say many of these children are falling through the cracks. Doctors generally report only grades 3 and 4 ototoxicity levels, but many of the kids studied had grades of 1 or 2.

Knight’s study found that 36 percent of patients who were examined would not have been reported as having hearing loss if only CTCAE grades 3 and 4 were considered.

Scientists want to boost awareness of hearing loss because it may soon be preventable and thereby limit adverse medical effects in children and subsequent problems later in life such as problems with behavior, energy, stress, self-esteem and social support.

Source: http://www.allheadlinenews.com/articles/7001436884