A seven-year-old child sees his doctor because food keeps getting stuck in his throat. He finds it hard to eat without also needing a glass of water to, as he puts it, “wash it down.”

Over the past few months, he also experienced some vomiting and upper abdominal pains.

Because he tends to be nervous, and especially now that the time has come to return to school after a peaceful summer holiday, his parents wonder if the difficulty in swallowing may be related to “nerves.”

The doctor, being a diagnostic sleuth with decades of experience, explains that there is indeed a mind-body connection, but asks about frequent choking during meals. The father and mother are divorced, and it seems that at Dad’s house, choking on food is more common. The father is a chef who loves to cook a wide variety of foods.

Ultimately, the doctor gets a consultation with a gastroenterologist who makes the final diagnosis: eosinophilic esophagitis (commonly abbreviated as EoE).

The prevalence of EoE is becoming increasingly common. There has been a five-fold increase since 2009.

My first encounter with EoE took place in a restaurant in Ottawa where I was seated next to an astute gastroenterologist who heard a child choking on his food a few feet away.

He jumped to the child’s rescue, asked the parents a few questions, and returned to our table a few minutes later, explaining to us that dysphagia (difficulty swallowing) can be due to a condition where the esophagus reacts to foods and then causes a wide range of symptoms such as vomiting, food impaction, chest pain, heartburn and abdominal pain.

The mechanism by which EoE manifests can be complex. It is not easy to diagnose in the average medical clinic.

The presence of a type of cell, called eosinophils, reflects the allergy component of our immune system. And yet, only 50 to 60 per cent of patients with EoE have elevated markers for an allergy (elevated immunoglobulin E levels).

When blood is taken in these patients, only 40 to 50 per cent will show a mildly elevated count of eosinophils.

Seeing an allergist instead of a gastroenterologist may add a few more pieces to the puzzle, but it rarely provides a final diagnosis of EoE. An allergist may help sort through food allergies and suggest dietary changes, but in the end the root issue of EoE may be missed.

Some doctors who were trained in the old days may be prone to ask for a barium swallow. This exposes the child to a high amount of radiation. Such a study has a low sensitivity for diagnosing EoE. In rare cases, narrowing of the esophagus may be discovered.

The definitive way of investigating a child who has dysphagia, food impaction, vomiting, a history of allergies and chest pains requires a gastroenterologist.

Such an expert may run a few more non-invasive tests, but in the end only an endoscopy (looking down the esophagus with a bright light) and a tissue biopsy in at least six different parts of the esophagus, searching for eosinophils, will clinch the final diagnosis.

The treatment of EoE consists of dietary changes, the use of medications known as proton pump inhibitors, or steroid therapy.

Families need to be counselled that EoE is a chronic issue. Some patients who respond to treatment enjoy the improvement and then stop their medication or dietary changes; a relapse of symptoms then becomes the confirmation to them that the issue is chronic and requires long-term management.

The majority of children with EoE who are tracked over a long period teaches us that EoE persists into adulthood; only 10 per cent develop a tolerance to food allergies.

Based on my unexpected education at a dinner table in Ottawa, and many decades of being a pediatrician, I know that on my own … the final diagnosis of EoE … is quite unlikely — a gastroenterologist is needed and, with that, much patience because the wait times to see these experts are ridiculously long.

There are always exceptions to get their attention: a child who finds that food is stuck, a child with painful swallowing, choking more often, loss of weight gain, and of course vomiting blood.

The final lesson for all doctors has to be that although the mind can impact our physical symptoms, and although anxiety is far more common than ever before, it is always wise to exclude all physical pathologies before suggesting that “It is probably due to the patient’s nerves.”

In an era where families appreciate doing their own research, I have found this website useful for additional education on EoE: www.eosnetwork.org

Dr. Nieman is the founder of Centre 70 Pediatrics. His columns for the Herald have appeared monthly since 1999.