Thyroid autoimmunity in chronic urticaria.

A subset of patients with idiopathic chronic urticaria (CU) has been recently classified as autoimmune on the basis of two main findings: association with thyroid autoimmunity and with anti-IgE and/or anti-IgE receptor antibodies. The association of CU with thyroid autoimmunity has been known since 1983, but its frequency varies in different reports. The objective of the present study was to verify the prevalence of thyroid antibodies (anti-thyroid peroxidase, TPO; thyroglobulin, TG; TSH-receptor, TSH-R) in two distinct series of CU: of known cause (70 cases, group A) and idiopathic (52 cases, group B). Twenty-three patients (M/F:7/16) of group A (33%) and 12 (M/F:4/8) of group B (23%) tested positive for at least one type of thyroid antibody. The difference was not statistically significant. Thyroid disease or altered serum TSH levels (requiring treatment) were present in 39% of group A and 42% of group B seropositive patients. In conclusion, the present study shows that CU, either of known cause or idiopathic, is more common in females than in males and is significantly associated with thyroid autoimmunity. These results were not expected on the assumption that autoimmune phenomena are a specific pattern of idiopathic CU. Thus, screening for thyroid autoimmunity and function is advisable in all patients with CU for the early identification of patients requiring either treatment of underlying thyroid dysfunction or follow-up.

Prevalence of silent coeliac disease in atopics.

BACKGROUND: Coeliac disease sometimes runs a subclinical/silent course and is often associated with immunologic and non-immunologic diseases. Although atopy is described as one of the most frequently associated conditions, the prevalence of coeliac disease in atopics has not yet been established. AIM: To evaluate the frequency of coeliac disease in an Italian series of atopics. PATIENTS AND METHODS: Sera from 401 consecutive atopics with no clinical evidence of malabsorption were tested for IgA antiendomysial antibodies by indirect immunofluorescence on human umbilical cord and IgA anti tissue transglutaminase by enzyme-linked immunosorbent assay Results. Four patients (1%) were found to be positive for both autoantibodies. Intestinal biopsy confirmed the diagnosis of active coeliac disease. One of the 4 coeliacs was also affected by Down's syndrome, autoimmune thyroiditis and coeliac hepatitis. In another case, a previously unknown severe iron deficiency was detected. CONCLUSIONS: The present study shows, for the first time, that the prevalence of coeliac disease in atopics is 1%, which is significantly higher than that in the general Italian population. Therefore, atopy should be considered a condition at risk and atopic patients routinely screened by means of specific autoantibody testing.