[Difficulties in the use of the Ridley and Jopling classification--a morphological analysis].

There are many difficulties in the use of the Ridley & Jopling classification in daily practice. The author identified the morphologic parameters whose variations permit to distinguish the polar types and borderline groups according to Ridley. If we avoid the inconstant histologic alterations we believe that this distinction depends basically on the following parameters: epithelioid cell, granuloma of epithelioid cells, numbers of lymphocytes and number of bacilli. A critical analysis is performed of each of these parameters and the author concludes that they are scarce, and that there are great difficulties for the identification and interpretation of their variations for classification purposes. These difficulties are even more important during the reactional episodes.