"It's not something you sit down with friends and chew and eat with a fork. You drink it" or receive it through a feeding tube. But often people weary of no food and go back on steroids.

Not all people with a form of eosinophilic disorder respond to the same treatment. There's great variation in both the degree of symptoms and the response to treatment.

The condition is not inherited. It can wax and wane. Sometimes food allergies are easy to spot; other times, there's no evident allergy at all. Many of the patients with an eosinophilic condition have allergies, hay fever, asthma, chronic hives, gastric reflux or atopic dermatitis, "a mark of the propensity of their immune system to react to things."

Those conditions can also wax and wane. If it becomes persistent, Gleich says, it's a considerable problem.

A human antibody — mepolizumab — taken intravenously shows promise of eliminating or reducing the need for corticosteroid treatment. But it's still in the study stage.

The most common form that Dr. Molly O'Gorman, an associate professor of pediatrics and a practitioner at Primary Children's Medical Center, sees is eosinophilic esophagitis.

A clinical trial is looking at whether the human antibody reslizumab helps with eosinophilic esophagitis by reacting against Interleukin-5, believed by some to be why eosinophils "get recruited into the esophagus," she says.

Children with eosinophilic esophagitis may be placed on a proton pump inhibitor to reduce reflux. If food allergies seem to be involved, they try an elimination diet to see if that resolves it. Unfortunately, allergy testing a lot of times isn't positive. They may move to a swallowed steroid.

When nothing else works, they eradicate it with elemental formula fed through a gastric tube and no regular food. "It's not a satisfactory lifestyle," O'Gorman says. "I've never had a patient die of the disorder, but it's miserable and disrupting. It can also lead to scarring of the esophagus."

Babies are more prone to eosinophilic colitis. But eosinophilic disorders can affect any age.

Even when she was tiny, Ashley had diarrhea. As she got older, she complained of stomachaches. Doctors initially thought she had celiacs disease, an intolerance for gluten, but a strict no-gluten diet brought no change. Since no one had any idea what else they could do for a while, they did nothing, her mom remembers.

"We were hoping it would go away. It got worse. She was complaining of stomachaches all the time. She'd miss school in the middle of the day," she says.

Ashley had three endoscopies, amid suspicion of celiac or irritable bowel or Crohn's. Then she was diagnosed with an inordinately high number of the eosinophils, which had settled in her digestive tract and were reacting to foods.