About half of patients with symptomatic esophageal eosinophilia achieved complete clinical and histologic remission on proton pump inhibitors (PPIs), according to a systematic review and meta-analysis of 33 studies.
“Our results support the concept of PPIs as first-line therapy in both children and adults,” Dr. Alfredo Lucendo of the Servicio de Salud de Castillo–La Mancha, Hospital General de Tomelloso, Albacete, Spain, and his associates wrote in the January issue of Clinical Gastroenterology and Hepatology. “Other effective alternatives, such as dietary or topical steroid therapy, likely might be set aside as second-line treatment, owing to long-term safety concerns (topical steroid therapy) and impairment of quality of life and nutritional inadequacy (dietary interventions).”
The study also confirmed that esophageal pH monitoring does not accurately predict therapeutic response to PPI therapy. “The performance of this test before histologic reevaluation on PPI therapy should be discouraged,” according to the researchers (Clin Gastroenterol Hepatol. 2015. [doi:10.1016/j.cgh.2015.07.041]). Eosinophilic esophagitis was first described as a distinct disorder about 20 years ago, but only recently was understood to be the most common cause of chronic esophageal symptoms among children and young adults. Some cases are now known to respond to PPI therapy, but reported remission rates have varied depending on study design and patient population, the investigators said. In addition, no one had systematically reviewed studies of PPI-responsive esophageal eosinophilia for quality or to determine the optimal type of PPI, dose, or treatment duration.
Therefore, the investigators searched MEDLINE, EMBASE, SCOPUS, and abstracts from the annual meetings of the American Gastroenterological Association, the American College of Gastroenterology, and United European Gastroenterology, identifying 33 studies of 619 patients with symptomatic esophageal eosinophilia. Eleven of the studies were prospective, of which only two were randomized controlled trials. The researchers defined a histologic response as less than 15 eosinophils per high-powered frame after PPI therapy. “Missing data regarding PPI therapy were common and prevented us from drawing conclusions on the most effective PPI drug and doses,” they said. In addition, most studies lacked structured or objective survey tools or other measures of clinical improvement, making it impossible to rule out self-adapted coping strategies as a main cause of improvement over time.
With those caveats in mind, about 61% of patients in the pooled analysis had a clinical response to PPI therapy (95% confidence interval, 48%-72%), and half achieved clinical and histologic remission (95% CI, 42%-59%), the investigators reported. Therapy was somewhat more effective when administered twice a day instead of once daily, when clinicians used esophageal pH monitoring, and when studies were prospective instead of retrospective, but the differences were not significant. Nor did therapeutic response significantly differ based on the age of patients, type of report, or quality of the study.
The overall findings “should be interpreted with caution because of poor-quality evidence, heterogeneity, and publication bias,” the researchers said. Prospective studies are needed to examine the best PPI, dose, and dosing interval to use in an initial trial in the clinic; to clarify long-term effects and dosing strategies; to assess the ability of PPIs to reverse fibrotic esophageal remodeling; and to examine the effects of the CYP2C19 genotype on clinical and histologic response, they added. “More quality evidence on pediatric PPI-responsive eosinophilic esophagitis is needed urgently,” they emphasized.
The authors reported no funding sources and had no disclosures.