T Matsushita1, R Kamide. 1. Department of Dermatology, The Jikei University School of Medicine, Tokyo, Japan.
Abstract
BACKGROUND: In parallel with the popular usage of topical ketoprofen, the number of reported cases of ketoprofen-induced photoallergic contact dermatitis has been increasing. It is clinically important to know the cross-reactivity of ketoprofen in order to avoid cross-sensitization caused by several structurally similar non-steroidal anti-inflammatory drugs (NSAID) on the market. METHODS: To evaluate the spectrum of cross sensitization, photopatch testing was performed on five patients with ketoprofen-induced photoallergic contact dermatitis using ketoprofen and other structurally similar chemicals, such as oxybenzone, tiaprofenic acid and suprofen. RESULTS: All five patients reacted positively to ketoprofen or ketoprofen plaster on photopatch testing. All four patients photopatch tested with related chemicals showed cross-photosensitization with tiaprofenic acid and suprofen. However, none of the patients reacted positively to oxybenzone. CONCLUSION: Either the diphenylketone moiety or a structurally similar tiophene-phenylketone moiety is important as the antigenic determinants of ketoprofen photoallergy. The arylpropionic acid side chain would not be involved.
BACKGROUND: In parallel with the popular usage of topical ketoprofen, the number of reported cases of ketoprofen-induced photoallergic contact dermatitis has been increasing. It is clinically important to know the cross-reactivity of ketoprofen in order to avoid cross-sensitization caused by several structurally similar non-steroidal anti-inflammatory drugs (NSAID) on the market. METHODS: To evaluate the spectrum of cross sensitization, photopatch testing was performed on five patients with ketoprofen-induced photoallergic contact dermatitis using ketoprofen and other structurally similar chemicals, such as oxybenzone, tiaprofenic acid and suprofen. RESULTS: All five patients reacted positively to ketoprofen or ketoprofen plaster on photopatch testing. All four patients photopatch tested with related chemicals showed cross-photosensitization with tiaprofenic acid and suprofen. However, none of the patients reacted positively to oxybenzone. CONCLUSION: Either the diphenylketone moiety or a structurally similar tiophene-phenylketone moiety is important as the antigenic determinants of ketoprofenphotoallergy. The arylpropionic acid side chain would not be involved.