Prognosis of infantile food protein‐induced enterocolitis syndrome in Japan

Background Although serum C‐reactive protein (CRP) and the percentage of eosinophils in peripheral blood (Eo) are increased at onset in infants with food protein‐induced enterocolitis syndrome (FPIES), the relationship of these laboratory findings to prognosis is presently unknown. Methods Correlation of serum CRP and Eo at onset with prognosis was analyzed in 32 patients with FPIES caused by cow's milk (CM). Results The rate of tolerance acquisition was 18.8%, 56.3%, 87.5%, and 96.9% at the ages of 6, 12, 24, and 36 months, respectively. Serum CRP increased in 50% of subjects at onset (median, 0.21 mg/dL; range, 0.05). Conclusions Serum CRP is not only an indicator of the activity of intestinal inflammation, it is also a useful parameter of poor prognosis in FPIES. In contrast, eosinophilia at onset could be used as a marker of good prognosis, suggesting that it has some beneficial effects in the pathophysiology of FPIES.