Diagnostic screening for contact allergy to mercaptobenzothiazole derivatives.
BACKGROUND
A patch test with an allergen mix used as screening test should be highly sensitive so that allergic patients are not missed. A previous analysis based on patch test data from 1990 to 1993 has shown that the mercapto mix lacked sensitivity. Chemical analyses on the stability of the mix components led to a new composition of the mix in 1995.


METHODS
The authors analyzed retrospectively patch test data from the Information Network of Departments of Dermatology to evaluate the sensitivity of the newly formulated mercapto mix and mercaptobenzothiazole (MBT) for detecting contact allergies to the 3 MBT derivatives contained in the present mix.


RESULTS
The new mercapto mix had a sensitivity of only 0.60, whereas MBT had a significantly higher sensitivity of 0.69. However, even this means that more than 30% of the patients allergic to MBT derivatives are missed. The combination of MBT and mercapto mix had a sensitivity of 0.77 for detecting contact allergies to the MBT derivatives.


CONCLUSIONS
The German Contact Dermatitis Research Group decided to test both mercapto mix and MBT within the standard series, and to apply the 3 single components of the mix in case of a positive reaction to the mix or MBT.
Geier
Johannes
J
Information Network of Departments of Dermatology, University of Göttingen, Göttingen, Germany.
Uter
Wolfgang
W
Schnuch
Axel
A
Brasch
Jochen
J
D000485:Allergens / Q000009:adverse effects / Q000737:chemistry; D052160:Benzothiazoles; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008499:Medical Records; D010328:Patch Tests / Q000379:methods / Q000592:standards*; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013844:Thiazoles / Q000009:adverse effects / Q000737:chemistry
D000485:Allergens; D052160:Benzothiazoles; D013844:Thiazoles; C028000:dibenzothiazyl disulfide