Shrimp allergy: clinical characteristics and food challenge outcome in a centre in the north of Portugal

Abstract

The average age was 34.9±10.3 years (24-63), 24 (80%) were female. The most common clinical symptoms were cutaneous in 57% and only 2 (7%) had a history of anaphylaxis and 1 presented unspecific symptoms. Twenty-four patients underwent SPT with shrimp and 8 (33%) of them were positive including the 2 with anaphylaxis. Twentythree patients underwent SPPT and 6 (26%) were positive including the 2 with anaphylaxis. Only these 2 patients had both positive SPT and SPPT. Fifteeen (73%) (out of 22 patients with IgE) had elevated total IgE. Specific IgE was increased in 14 (48%) with values ranging between 0.37 and 91.7KU/L. The 6 patients with positive SPPT also had elevated sIgE. Of the 26 (87%) who performed SPT, 22 (85%) were house dust mite (HDM) positive, including the 7 (87.5%) patients with positive shrimp SPT. Nineteen patients underwent OFC: 14 (74%) were negative, 3 (16%) were positive and 2 (10%) unconclusive. The 3 patients with positive OFC had negative SPPT. The 2 patients with a history of serious anaphylaxis did not undergo OFC. The cumulative doses varied between 31.1and 128.9g. The doses of the positive OFC were between 52.0 and 64.8 g. With respect to comorbid conditions, 10 (33%) had asthma and/or rhinitis; 70% were allergic to HDM and 30% were allergic to both HDM and pollens. Two of the 3 patients with positive OFC as well as the 2 with serious anaphylaxis had a history of allergic asthma and/or rhinitis.