North American Contact Dermatitis Group patch-test results, 2001-2002 study period.
BACKGROUND
Allergic contact dermatitis is a significant cause of cutaneous disease affecting many individuals in the home and at the workplace. Patch testing is the most worthwhile diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis.


OBJECTIVE
This study reports the results of patch testing from January 1, 2001, to December 31, 2002, by the North American Contact Dermatitis Group (NACDG).


METHODS
Patients were tested with an extended screening series of 65 allergens. A standardized patch-testing technique was used. Data from these patients were recorded on a standardized computer entry form and analyzed.


RESULTS
Sixty-five allergens were tested on 4,913 patients. The top 10 allergens remain the same in this study period as in the 1999-2000 study period: nickel sulfate (16.7%), neomycin (11.6%), Myroxilon pereirae (balsam of Peru) (11.6%), fragrance mix (10.4%), thimerosal (10.2%), sodium gold thiosulfate (10.2%), quaternium-15 (9.3%), formaldehyde (8.4%), bacitracin (7.9%), and cobalt chloride (7.4%). Of the 4,913 patients tested, 69% had at least one positive allergic patch-test reaction. Of all patients, 15.8% had occupation-related dermatitis; 15.4% were determined to have irritant contact dermatitis, and 11.1% of the 15.4% had a relevant reaction to an occupational irritant. Of all patients tested, 16.7% had a relevant reaction to an allergen not in the NACDG standard series, and 5.5% had a relevant reaction to an occupational allergen not in the standard series.


CONCLUSIONS
Our findings once again reinforce the need for a more comprehensive group of diagnostic allergens than those found in the standard screening kits. The usefulness of patch testing is enhanced when a greater number of allergens are tested, especially nonstandard allergens occupationally encountered.
Pratt
Melanie D
MD
North American Contact Dermatitis Group. kellypratt@sympatico.ca
Belsito
Donald V
DV
DeLeo
Vincent A
VA
Fowler
Joseph F
JF
Fransway
Anthony F
AF
Maibach
Howard I
HI
Marks
James G
JG
Mathias
C G Toby
CG
Rietschel
Robert L
RL
Sasseville
Denis
D
Sherertz
Elizabeth F
EF
Storrs
Frances J
FJ
Taylor
James S
JS
Zug
Kathryn
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens; D002648:Child; D002675:Child, Preschool; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis* / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010328:Patch Tests / Q000379:methods*; D011237:Predictive Value of Tests; D014481:United States / Q000453:epidemiology
D000485:Allergens