In 1972, Sharp et al described the mixed connective tissue disease; such a description corresponded to an apparently distinct rheumatic disease syndrome associated to U1RNP, which is an extractable nuclear antigen or ENA (1). After this clever description, different overlap syndromes that did not meet the EMTC criteria were described. Conceptually Alarcón-Segovia coined the term of “shared autoimmunity”, which was defined by the presence of two or more data compatible with autoimmune disease; such category of disease describes signs or symptoms of certain autoimmune connective diseases, for instance Rupus corresponds to lupus erythematosus associated..

No abstract

Background: Human anisakidosis is a parasitic disease whose intestinal form shares several characterictics with Crohn’s disease (CD), like the ileocolonic location predominantly and the presence of granuloma. Methods: 73 CD patients diagnosed according to Lennard-Jones’ criteria were studied. The disease activity was measured by means of Harvey-Bradshaw Index. Different clinical variables were analyzed. Antigenic extract of Anisakis simplex larvae extracted from blue whiting was prepared. Determination of IgG, IgM, IgA and total specific immunoglobulin against A. simplex were carried out in sera by enzyme-linked immunosorbent assay. Immunorecognition patterns of these sera were realized by immunoblotting analysis. Results were compared with prevalence of antibodies anti-Anisakis in 251 healthy controls. Results: 29% of CD patients showed detectable specific total Ig (G+M+A) against A. simplex (95% CI, 19–41). For IgG, IgM and IgA the percentages were 44, 18 and 53% (95% CI, 32–56, 10–26, and 41–65) respectively. In positive specific total Ig cases CD was localized mainly in ileum. In IgG-, IgM- and IgA-positive cases the location was predominantly ileocolonic. CD activity index was higher for groups with positive IgA (2.86 vs. 5.55; p < 0.05). Conclusion: Patients with CD have high prevalence of specific immunoglobulin against A. simplex. Specific IgA are associated to higher activity index of CD.