A coloração de, lipídios pelo Sudão lll. Importância na classificação histopatológica da hanseníase

Abstract

1) Lipid-staining techniques of histological sections should be used routinely, in addition to Hematoxylin-Eosin and staining for bacilli, to enhance diagnostic precision of the clinical forms of Hanseniasis. 2) The use of the Sudan III In 8972 consecutive cases lead us to the conclusion that, despite the slight disadvantages of easy cristalization and long term loss of stain in the preparations, it is essential for a correct histological diagnosis.
3) In Indeterminate Hanseniasis lipid staining is always negative. Some cases, clinically considered as Indeterminate forms were actually shown to be incipient Virchowian or transitional forms through the finding of typical Virchow cells containing both bacilli and lipids. The early discovery of such cases can only be carried through systematic search for lipids on specifical staining. 4) In Tuberculoid Hanseniasis with quiescent granulomas, lipids are never found. 5) In Reactional Tuberculoid Hanseniasis, pathological lipids are not found but a yellowish hue, light and diffuse, is observed due to the edema fluid which permeates and disrupts granulomas. This is due to partial solubilization of the stain in the edema fluid which contains a fraction of normal lipoid; Pathologists unacquainted to such an image might consider it positive: thus it is a false-positive reaction. 6) Tuberculoid Hanseniasis is considered in reaction when only some of the granulomas show edema disjoining epithelioid cells; the diffuse yellowish tone is observed exclusively in those undergoing such a transitional phase. 7) In active Virchowian Hanseniasis lipid search is positive over 99% of the cases.
8) In regressive and residual Virchowian Hanseniasis, lipids are present in practically all cases (100%).
In terminal stages lipid-deposits are found also in big vacuoles, cavities and inside the cytoplasm of giant foreign-body cells. 9) In Borderline Hanseniasis lipids were found in 758% of cases. 10) In Borderline Hanseniasis it is particularly important to distinguish between the two types of lipid-images because both can be found in the same preparation:
— localized lipid finely granulous or in droplets, inside Virchow cells;
— diffuse, light yellow lipoids, in tuberculoid granulomas with edema.