Endoscopic findings alone are not sufficient to diagnose eosinophilic esophagitis and instead, biopsies are needed, reported Ms. Hannah P. Kim and her colleagues in the September issue of Clinical Gastroenterology and Hepatology.
Indeed, while findings like rings, strictures, and linear furrows ought to raise suspicion, a meta-analysis of more than 4,600 patients confirms that "low sensitivity and variable predictive values make them inadequate both for the diagnosis of EoE [eosinophilic esophagitis] and for the decision of whether or not to obtain biopsies."
Ms. Kim of the Center for Esophageal Diseases and Swallowing at the University of North Carolina, Chapel Hill, and her colleagues analyzed data from 80 articles and 20 abstracts that included a total of 4,678 patients with EoE and 2,742 patients without, who served as controls.
The studies were culled from PubMed, EMBASE, and gastroenterology meetings. All studies included in the analysis had more than 10 patients with EoE and provided information on the associated endoscopic findings. The mean age of participants ranged from 6 years to 55 years in the different studies.
In an analysis, the authors found that the overall pooled prevalence of esophageal rings in the sample was 44%. For strictures, the prevalence was 21%, and for linear furrows, 48% (Clin. Gastroenterol. Hepatol. 2012 [doi:10.1016/j.cgh.2012.04.019]).
Narrow-caliber esophagus findings had a pooled prevalence of only 9% of the total sample, while the presence of white plaques or exudates was 27%. Visible pallor or decreased vasculature on endoscopy was seen in 41% of patients, and erosive esophagitis in 17%.
"The endoscopic examination was normal in 17% of cases," added the authors.
They also found a difference in prevalence according to age of patients. For example, rings and strictures were more prevalent in adults (57% and 25%, respectively) than in children (11% and 8%; P less than .05 for each).
"On the other hand, white plaques and pallor or decreased vasculature were more prevalent in children (36% and 58%) than in adults (19% and 18%; P less than .05 for each)."
Finally, Ms. Kim and her associates assessed the overall sensitivity, specificity, pooled positive predictive value (PPV), and pooled negative predictive value (NPV) for each of the assessed endoscopic characteristics.
For rings, the overall sensitivity was 48%, the specificity was 91%, the PPV was 64%, and NPV was 84%. Strictures had an overall sensitivity of 15%, specificity of 95%, PPV of 51%, and NPV of 76%.
"The operating characteristics were slightly higher for linear furrows, with a sensitivity of 40%, specificity 95%, PPV 73%, and NPV 83%," wrote the authors.
And for the endoscopic finding of pallor and/or decreased vasculature, sensitivity was 43%, specificity 90%, PPV 65%, and NPV 79%.
"In contrast to the low sensitivity of individual endoscopic findings, when examining the presence of at least one endoscopic finding, an abnormal endoscopy had a sensitivity of 87%, specificity of 47%, PPV of 42%, and NPV of 89%," the authors added.
"Although endoscopic features of EoE such as esophageal rings, linear furrows, and white plaques or exudates are often considered to be typical features of EoE, these are not always identified by endoscopists," wrote the researchers.
And while most patients with EoE have abnormal findings on upper endoscopy examinations, "the sensitivity values of individual endoscopic findings were modest, and although the specificity values were higher, the predictive values were inadequate for diagnostic purposes."
"Esophageal biopsies should be obtained from all patients who present with symptoms of EoE, regardless of the endoscopic appearance of the esophagus."
The authors stated that the study was supported by grants from the National Institutes of Health and the Doris Duke Charitable Foundation. They stated that they had no individual disclosures.