In vitro tests for the diagnosis of aspirin and salicylate sensitivity

Abstract

Sensitivity to aspirin, non-steroidal anti-inflammatory drugs (NSAIDs) and also dietary salicylate is an increasingly important and observed phenomenon. The reliable diagnosis of individuals with these disorders is of great importance, given the use of these drugs as a prophylactic medication. Many of the symptoms seen in patients associated with this sensitivity to these drugs include dermatitis, nasal polyps, persistent cough, rhinitis, skin problems, stomach irritation, swelling of face and urticaria are also seen in salicylate intolerance. These symptoms are similar to those seen in the allergic patient, however, the reaction to salicylate is not an allergy. A major clinical problem is that no current method of food intolerance or allergy in vitro testing and diagnosis has currently been established to predict those people with this condition. This study was designed to search for new markers, which could be used to predict with high specificity and sensitivity, subjects with aspirin induced asthma (AIA). This was done by investigating patients with known aspirin sensitivity and comparing them with healthy individuals and atopic non-aspirin sensitive patients. All subjects used (male/females- age range 21-68 years old) were divided into 4 groups (atopic aspirin sensitive, non-atopic aspirin sensitive, atopic non-aspirin sensitive, and healthy volunteers) according to the clinical history and confirmed positive skin test to common allergens. Flow cytometer was used to assess the role of activated basophils in AIA and detect the expression of CD63 in their blood after stimulation of the cells with L-ASA. A posterior rhinomanometer was used to assess a challenge technique that was sensitive to local stimulation by L-ASA. Cytokine (IL-4) expression in lymphocytes was determined using ELISA and IL-4 messenger RNA levels investigated using RT-PCR. The release of PGF2α from plasma protein on those patients was detected by ELISA. The results obtained in this study, suggest that up regulation of CD63 expression by aspirin and Nasal airways resistance test (NART) following aspirin challenge, may prove to be useful diagnosis tool in these patients. The study also indicates that lymphocyte responses as evidenced by IL-4 release are not affected by salicylate sensitivity. The significance of these results is also discussed.