BACKGROUND: The study of histopathological alterations in relation to Erythema chronicum migrans (Lyme disease) and the demonstration of its etiological agent in tissues have been little divulged in our Country and region. OBJECTIVES: To describe the main histopathological alterations in the cutaneous biopsies of patients with clinical diagnosis of Erythema chronicum migrans (ECM). To demonstrate Borrelia sp in the histological section. MATERIAL AND METHODS: Skin biopsies were taken from 31 patients and embedded in paraffin to prepare the histological section. These sections were stained with Hematoxylin and Eosin (HE) to investigate the main histopathological alterations and with Warthin-Starry silver stain and modified Warthin-Starry stain, at pH 4.0 (pyrocatechol), to demonstrate Borrelia sp. RESULTS: The main alterations verified were: in the epidermis, spongiosis in 15 cases (44.12%); in the dermis, an infiltrate comprised of lymphocytes, histiocytes and eosinophils in 8 cases (15.69%). The infiltrate in the dermis was found to be perivascular and angiocentric in 9 cases (29.04%). Borrelia sp was detected in 1 case (3.22%) using Warthin-Starry silver stain. However with modified Warthin-Starry stain, at pH 4.0 (pyrocatechol), no case tested positive out of the 31 cases investigated. CONCLUSION: The infiltrations in the dermis were composed of lymphocytes, histiocytes and eosinophils presented the following arrangement: angiocentric and interstitial infiltrate; perivascular and interstitial infiltrate. Composition and arrangement were considered of major relevance for the diagnosis of ECM. For the first time in the Brazilian Amazon region, the presence of Borrelia sp was demonstrated in the biopsy of a patient with diagnostic suspicion of ECM using histological sections colored by Warthin-Starry silver stain.
Borrelia; Lyme disease; Erythema chronicum migrans; histology