|
Abstract
|
BACKGROUND: Skin reactions to the sting of the imported fire ant have characteristic clinicopathological features.
METHODS: One case of experimental envenomation was prospectively followed during 48 hours, with biopsies. In addition, six cases from our laboratory were retrospectively evaluated histopathologically for the following features: spongiosis, exocytosis (and type of cells), pustule formation, erosion/ulceration, epidermal necrosis, scale/crust, papillary dermal edema, inflammatory dermal infiltrate (cell type, density, depth, distribution, shape), red blood cell extravasation, vasculopathy, vasculitis.
RESULTS: The typical lesion follows a very distinctive clinical and histopathologic evolution over 48 hours, with the formation of a subepidermal pustule overlying a wedge shaped area of dermal collagen basophilic degeneration with scattered neutrophils. In the six cases retrieved from our files, the main features were a superficial and deep dermal, perivascular, periadnexal and interstitial infiltrate consisting of neutrophils, with basophilic degeneration of the collagen. A subepidermal pustule was noted in half of the cases.
CONCLUSIONS: In biopsies taken in a clinical setting, even in the absence of the characteristic subepidermal pustule, the diagnosis of imported fire ant sting can be suspected if there is a superficial and deep perivascular, periadnexal and interstitial infiltrate composed of neutrophils, with some basophilic denaturation of collagen.
This article is protected by copyright. All rights reserved.
Language: en |