New Positive Patch Test Reactions at Day 7 | PracticeUpdate

New Positive Patch Test Reactions at Day 7

Contact Dermatitis

TAKE-HOME MESSAGE

• Among the 3292 patients patch tested using the TRUE Test panels 1 and 2 along with additional investigator-loaded allergens, 447 patients had a new positive reaction at day 7. Results showed that the most common allergens to show a new positive result at day 7 were neomycin sulfate, 2-bromo-2-nitropropane-1,3-diol, budesonide, and diazolidinyl urea. Nickel sulfate was associated with the highest number of doubtful reactions at day 3, which became strong positive reactions by day 7. Individuals 61 years and older were more likely to have a new positive reaction on day 7; however, this may be due to the decreased exposure of younger generations to neomycin sulfate in the Netherlands due to the recent regulations.

• New day-7 positive reactions were not significantly associated with gender, history of atopic dermatitis, or occupational dermatitis.

– Caitlyn T. Reed, MD

Abstract 

BACKGROUND

Not performing a D7 patch test reading might result in missing positive patch test reactions.

OBJECTIVE

To investigate the added value of the D7 patch test reading for individual allergens and to identify patient characteristics and allergen groups associated with new positive D7 reactions.

METHODS

Data from patients patch tested between 2008 and 2018 with the extended European baseline series were analysed. Patch test readings were performed at D3 and D7. Positive reactions were categorized into positive at D3 or new positive at D7.

RESULTS

A total of 3292 patients were consecutively patch tested with at least 43 allergens of the TRUE Test panels 1 and 2 supplemented with investigator-loaded allergens. In total 447 (13.6%) patients showed new positive reactions at D7. In univariable regression analysis patients between 18 - 30 years showed a negative association with new positive D7 reactions. Significantly more D7 positive reactions were seen for topicals (OR=2.60, 95%CI; 1.92 - 3.51) and corticosteroids (OR=1.87, 95%CI; 1.09 - 3.21). No associations were found between sex, atopic dermatitis and occupational dermatitis and a new positive D7 reaction.

CONCLUSION

A D7 reading to identify new positive patch test reactions is of added value, especially for topicals and corticosteroids.

Contact Dermatitis

New Positive Patch Test Reactions at D7 – The Additional Value of the D7 Patch Test Reading

Contact Derm 2019 May 22;[EPub Ahead of Print], CCA van Amerongen, R Ofenloch, D Dittmar, MLA Schuttelaar 

http://www.practiceupdate.com/content/new-positive-patch-test-reactions-at-day-7/84075

Sent from my iPhone

Benjamin Hidalgo-Matlock
Skin Care Physicians of Costa Rica

Clinica Victoria en San Pedro: 4000-1054
Momentum Escazu: 2101-9574

Please excuse the shortness of this message, as it has been sent from
a mobile device.