Role of the Skin Prick Test in Urticaria Patients.

ABSTRACT

Background Urticaria, a vascular reaction of the skin, is marked by the transient appearance of erythematous papules or plaques (wheals) of varying sizes that are blanchable and associated with severe pruritus which lasts from a few hours to days. The etiological factors for urticaria include food, drugs, bacterial foci, pollen, fungi, dust, worms, physical stimuli, stress, anxiety, insect stings, etc. Skin prick tests (SPTs) represent the cheapest and most effective method to diagnose immunoglobulin E-mediated type 1 allergic reactions such as urticaria. A history suggestive of clinical sensitivity supported by a positive test strongly implicates the allergen in the disease process. In this study, we aimed to detect the common allergens and correlate the findings of SPTs with various epidemiological characteristics of urticaria patients. Methodology A total of 100 patients with urticaria were included in this study. After receiving written and informed consent from patients, SPTs using a battery of 45 allergens were performed. Results In our study, SPT positivity was seen in 88 (88%) patients. The highest sensitization was noted toward Dermatophagoides pteronyssinus (house dust mite) (30%), followed by D. farinae, Cynodon dactylon, and peanuts (each comprising 24%), and Ailanthus excelsa (20%). Conclusions Finding the causative allergen in urticaria is often a difficult and long-drawn process, both for the physician and the patient. Our study identified an allergen in 88% of patients with urticaria, thereby showing that the SPT is a cost-effective, easy, and reliable tool for diagnosing and guiding treatments in urticaria patients.