Signs of anin situinflammatory reaction in scars of human American tegumentary leishmaniasis

Abstract

Skin inflammation plays an important role during the healing of American tegumentary leishmaniasis (ATL), the distribution of cells in active lesions may vary according to disease outcome and parasite antigens in ATL scars have already been shown. We evaluated by immunohistochemistry, 18 patients with 1- or 3-year-old scars and the corresponding active lesions and compared them with healthy skin. Small cell clusters in scars organized as in the active lesions spreaded over the fibrotic tissue were detected, as well as close to vessels and cutaneous glands, despite a reduction in the inflammatory process. Analysis of 1-year-old scar tissue showed reduction of NOS2, E-selectin, Ki67, Bcl-2 and Fas expression. However, similar percentages of lymphocytes and macrophages were detected when compared to active lesions. Only 3-year-old scars showed reduction of CD3(+), CD4(+) and CD8(+)T cells, in addition to reduced expression of NOS2, E-selectin, Ki67 and BCl-2. These results suggest that the pattern of cellularity of the inflammatory reaction observed in active lesions changes slowly even after clinical healing. Analysis of 3-year-old scars showed reduction of the inflammatory reaction as demonstrated by decrease in inflammatory cells and in the expression of cell-activity markers, suggesting that the host-parasite balance was only established after that period.

Histopathological and immunohistochemical aspects of American cutaneous leishmaniasis before and after different treatments*

“…18,20 In addition, the PCR procedure enabled the identification of leishmanial DNA, showing the persistence of the parasite after years of being clinically cured. 17,18 The absence of complete resolution of the lesion suggests a persistence of the parasite antigens, which is related to the maintenance of the local inflammatory response.…”

Two Women Presenting Worsening Cutaneous Ulcers during Pregnancy: Diagnosis, Immune Response, and Follow-up

“…Amastigote numbers present in lesions of nonpregnant ATL patients (average of three patients) before treatment are shown as comparison. The results are expressed as number of parasites per mm 2 , using a grid-scale consisting of 20×20 subdivisions in an area of 10 mm 2 ×10 mm 2 , adapted to slides as previously described [24]. The results shown are median ± SEM.…”

Reactivation of cutaneous and mucocutaneous tegumentary leishmaniasis in rheumatoid arthritis patients: an emerging problem?

“…In some individuals, the patient may also experience lesions of the mucosal tissue, especially of the upper respiratory and digestive tract, producing discomfort swallowing or breathing. Oftentimes, the infections are chronic and can reactivate several times during the patient’s life, since parasites are known to persist at the lesions 3 , 4 . …”