Clinical usefulness of morphine skin prick test in diagnosis of allergic diseases

Choi, Inseon S; Park, Seog Chea; Kang, Kwang Won

Abstract

BACKGROUND: Few studies have demonstrated an enhanced skin responsiveness to opiates in atopic subjects.
OBJECTIVE
To determine whether the skin response to morphine is increased in atopics and to assess the clinical usefulness of morphine skin prick test in diagnosis of allergic diseases. METHOD: Allergy skin prick tests were performed using 55 common allergens, histamine, and morphine in 158 patients with allergic diseases.
RESULTS
Wheal and flare sizes for morphine (1mg/mL) were significantly related to and smaller than those for histamine (1mg/mL). Although the proportion of subjects with allergic rhinitis and the level of serum total IgE were not different between responders (wheal >- 2mm) and nonresponders to morphine, the positive response rate to allergens was significantly lower in nonresponders. The flare sizes for morphine were significantly higher in positive allergen test group (A/H ratio >- 0.5). Among positive allergen test group, the subjects with atopy score >- 5 showed a larger flare size for morphine than those with atopy score < 5 while the sizes for histamine were not different.
CONCLUSION
Morphine skin prick test is helpful for detecting false negative responses to allergens, and morphine skin test responses are increased in highly atopic patients probably due to enhanced mast cell releasability.