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. 2009;54(1):56-8.
doi: 10.4103/0019-5154.48989.

Late reaction, persistent reaction and doubtful allergic reaction: the problems of interpretation

Nilendu Sarma  1
Affiliations

Late reaction, persistent reaction and doubtful allergic reaction: the problems of interpretation

Nilendu Sarma. Indian J Dermatol. 2009.

Abstract

The standard method of patch test reading is to read the test site for any positive allergy at 48 hr and then again at 72/96 hr. A late reading on the seventh day is also advised to exclude the irritant reaction (IR) and to notice some delayed development of allergic reaction. However, multiple visits are often difficult for the patient; therefore, this late reading is sometimes omitted. Here a case of plantar hyperkeratosis, due to allergic contact dermatitis, is reported with some insight into interpretation of the patch test. The patient showed delayed patch test reaction to formaldehyde and colophony, which has never been reported before.

Keywords: Doubtful reaction; late reaction; persistent reaction.

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Conflict of interest statement

Conflict of Interest: Nil.

Figures

Figure 1
Figure 1
Hyperkeratosis involving toe tips
Figure 2
Figure 2
Vesicles at the test site of formaldehyde on the eighth day of reading
Figure 3
Figure 3
Erythema over chromate still persisting with mild erythema over formaldehyde on Day 26
See this image and copyright information in PMC

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References

    1. Wahlberg JE, Lindberg M. Patch testing. In: Frosch PJ, Menne T, Lepoittevin JP, editors. Contact Dermatitis. 4th ed. Berlin: Springer; 2006. pp. 365–90.
    1. Malten KE, den Arend JA, Wiggers RE. Delayed irritation: hexanediol diacrylate and butanediol diacrylate. Contact Dermatitis. 1979;5:178–84. - PubMed
    1. Fisher AA. Contact Dermatitis. 3rd ed. Philadelphia: Lea-Ferbiger; 1986. Role of patch testing in allergic contact dermatitis; pp. 25–38.
    1. Bygum A, Andersen KE. Persistent reactions after patch testing with TRUE testTM panel 1 and 2. Contact Dermatitis. 1998;38:218–20. - PubMed