Histological and immunohistochemical aspects of cutaneous leishmaniasis in nicaragua

Abstract

Sixty skin biopsies of fifty-eight non-treated patients with cutaneous leishmaniasis from Nicaragua were studied. Biopsies were classified according to Ridley's histopathologic groups: 36 (60%) were included in group B (diffuse necrosis), 14 in group C (focal necrosis), 7 (11.6%) in group D (reactive tuberculoid). Only three biopsies remained unclassified. None of our cases could be included in groups A and E. Immunohistochemistry disclosed in 17 cases Russel's bodies secreting IgM and only one IgG positive. There was no correlation between the histopathologic groups and the presence of Russel's bodies. However, we believe the presence of Russel's bodies help the diagnosis of leishmaniasis. Correlation between morphological patterns and the different leishmania species was also considered.

Proposal of a histopathological predictive rule for the differential diagnosis between American tegumentary leishmaniasis and sporotrichosis skin lesions

“…The tissue reaction in ATL is mainly characterized as nonsuppurative 12 . However, neutrophils associated with a vasculitis‐like reaction, 29 necrosis 8,30 or even suppurative granulomas 31,32 have been described. ‘Suppurative granuloma’ was the investigated marker with the highest strength of association in sporotrichosis.…”

“…Finally, we stress that this study was performed on samples in which the microorganisms were not detected by standard histopathology despite positive detection of the infectious agents in cultures. Because parasite‐rich cases may exhibit tissue responses different from those in which parasites are not present, 20,30,45 the histopathological score must be applied only after a negative careful search for the infectious agent.…”