Eosinophilic gastroenteritis and Anisakis

Background The differential diagnosis of eosinophilic gastroenteritis (EG) includes, among other diseases, parasitic infections such as anisakiasis, w hich has acquired worldwide importance. Methods We reviewed all patients referred to our allergy service who had be en diagnosed as having primary EG to determine the possible role of Anisaki s simplex in the etiopathology of the disease. All patients (n = 10) were s tudied and diagnosed as having primary EG between 1989 and 1996, inclusive. Two different groups of subjects were used as controls: group A (149 subje cts without digestive disorder) and group B (10 subjects with digestive dis order different from EG). Cutaneous prick tests were performed with the mai n foods, aeroallergens, and commercial extract of A. simplex. Total and spe cific serum IgE was measured in all patients. Gastric or gut histologic spe cimens were re-examined in five cases. Results Peripheral eosinophilia was detected in 40% of the patients with EG , and sensitization to A. simplex was detected in 80% of these. In both con trol groups, the rate of sensitization to A. simplex was 10%. Sensitization to A. simplex in EG patients with respect to control groups A and B showed odds ratios (OR) of 36 and 40, respectively. In one case, serialization of the histologic section allowed us to observe a whole Anisakis larva. Conclusions Immunologic methods to detect specific antibodies against Anisa kis should be used routinely before diagnosing EG as primary disorder. Prev entive measures are of capital importance.