ISSN:
1600-0536
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
This study has attempted to distinguish between allergic and irritant reactions to patch tests by semiquantitative histological methods. The extent of perivascular chronic inflammatory infiltrate at 72h in irritant patch test reactions to sodium lauryl sulphate was shown to be small and very consistent. whereas in allergic reactions in nickel sulphate it was generally larger and more variable in size (p 〈 0.02). The two major lymphocyte subsets (T4 and T8) were randomly intermixed in both types of reaction and formed the major component of both the perivascular and diffuse dermal infiltrate, without any evidence of selective migration The T4:T8 ratios were similar in focal and diffuse infiltrates. The number of T6 dendritic (putative Langerhans) cells in the epidermis (per mm inner epidermal length) was usually greatly reduced in irritant reactions (5–16 mm −1, mean 10 mm−1) but remained within normal limits in allergic reactions (6–33 mm−;1, mean 21 mm–1) (p 〈0.001). Comparable results were seen with other irritants (mercuric chloride and benzalkonium chloride) and older allergens (neomycin sulphate. ethylene diamine and potassium dichromate).In additional experiments, pairs of biopsies were taken from the reaction and from adjacent unaffected skin. The T6 cell density in the epidermis did not significantly differ between allergic reactions and control skin. By contrast, (lie irritant reactions had fewer T6 cells than the control skin (p 〈 0.001).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1600-0536.1985.tb02530.x
