American Board of Internal Medicine (ABIM) Certification Practice Exam

How is eosinophilic esophagitis diagnosed?

1. Presence of greater than 15 eosinophils/hpf on esophageal biopsy and exclusion of GERD

2. Endoscopy with no biopsies needed

3. Blood tests for specific antibodies

4. Patient history alone

The correct answer is: Presence of greater than 15 eosinophils/hpf on esophageal biopsy and exclusion of GERD

The diagnosis of eosinophilic esophagitis is established primarily through histological examination of esophageal biopsy specimens. The presence of more than 15 eosinophils per high-power field (hpf) is a key histopathological finding that supports the diagnosis of eosinophilic esophagitis. Additionally, it is crucial to exclude gastroesophageal reflux disease (GERD) when making this diagnosis, as GERD can also cause eosinophilic infiltration and symptoms similar to those found in eosinophilic esophagitis. Therefore, the combination of finding elevated eosinophils in the esophagus and ruling out other conditions (like GERD) confirms the diagnosis of eosinophilic esophagitis. In contrast, diagnosing this condition solely through endoscopy without biopsy does not provide the necessary evidence of eosinophilic infiltration. Relying exclusively on blood tests for specific antibodies is insufficient for diagnosis as these tests do not directly assess the esophagus. Lastly, patient history alone can provide valuable context in the clinical picture but does not fulfill the diagnostic criteria necessary to confirm eosinophilic esophagitis without histological evidence.