Ectopic Cutaneous Schistosomiasis mansoni in the Sacral Region

The authors report one case of late cutaneous Schistosomiasis mansoni in a biopsy of a skin lesion in the sacral region in a 51-year-old female living in Contagem, Minas Gerais. The patient was treated successfully with oxamniquine (Mansil®)

American tegumentary leishmaniasis : effectiveness of an immunohistochemical protocol for the detection of leishmania in skin.

Background: American tegumentary leishmaniasis (ATL) is endemic in Latin America, where Brazil has over 27 thousand cases per year. The aim of the present study was to develop an immunohistochemical method (IHC) for ATL diagnosis. For this purpose, we used serum from a dog naturally infected with Leishmania (L) infantum (canine hyperimmune serum) as the primary antibody, followed by a detection system with a secondary biotinylated antibody. Methodology: Skin samples were obtained from 73 patients in an endemic area of Caratinga, Minas Gerais (MG) State, Brazil all testing positive for ATL with the Montenegro skin test, microscopy, and PCR. Canine hyperimmune serum of a dog naturally infected with Leishmania (L.) infantum was employed as a primary antibody in an immunohistochemical diagnostic method using streptavidin-biotin peroxidase. To assess the specificity of this reaction, IHC assays employing two monoclonal antibodies were carried out. As the polymer-based technology is less time-consuming and labor intensive than the IHC labeled streptavidin-biotin peroxidase method, we compared the two methods for all samples. Results: The IHC method detected ATL in 67 of the 73 cases (91.8%). Immunolabeled parasites were primarily detected inside macrophages either in the superficial or the deep dermis. Detection was facilitated by the high contrast staining of amastigotes (dark brown) against the light blue background. A lower detection rate (71.2%) was observed with the both of the monoclonal Leishmania antibodies compared to the canine hyperimmune serum. This may have been due to a nonspecific background staining observed in all histological samples rendering positive detection more difficult. The higher efficacy of the canine hyperimmune serum in the IHC method was confirmed by the method using streptavidin-biotin peroxidase as well as that with the polymer-based technology (biotin-avidin-free system). Conclusions: The data are encouraging with regard to validating IHC as a standard alternative method for ATL diagnosis

Parasite load of 73 skin fragments of a sample subjected to the immunohistochemical methods of streptavidin peroxidase, using hyperimmune serum from a dog naturally infected by <i>Leishmania infantum chagasi</i> (dilution 1∶100) and monoclonal antibody anti-<i>Leishmania</i> lipophosphoglycan (LPG) (Mo-anti LPG) (dilution 1∶100).

<p>Mann-Whitney p = 0.0001.</p

A–E: Fragment of skin of a patient with LCL, Caratinga, MG, Brazil.

<p>(A, B) Immunohistochemical labeling of amastigotes of <i>Leishmania</i> with an aliquot of a commercial monoclonal anti-<i>Leishmania</i> antibody and the streptavidin-biotin peroxidase method. (A) Low magnification showing a brown background evidenced by the cytoplasm of the epithelial layer cells (arrowheads). Bar = 32 µm. (B) Higher magnification showing intense non-specific staining visible as dark brown cytoplasmic staining of epithelial (arrowheads) and inflammatory mononuclear cells (macrophages) with intracellular amastigotes of <i>Leishmania</i> in the dermis (arrows) Bar = 16 µm. (C,D) Immunohistochemical labeling of amastigotes of <i>Leishmania</i> using dog hyperimmune serum as the primary antibody with the streptavidin-biotin peroxidase method (C) Low magnification showing light-blue stained background. Bar = 32 µm. (D) Higher magnification showing dark-brown-stained intracellular amastigotes of <i>Leishmania</i> within macrophages in the dermis (arrows) and light-blue-stained background. Bar = 16 µm; (A–D) Immunohistochemistry with the streptavidin peroxidase method counter-stained with Harris’s hematoxylin. (E) Observe immunolabeled amastigotes inside macrophages associated areas of tissue debris (arrow) Epithelium (Ep), Dermis (De).</p

A–D: Fragment of skin of a patient with LCL Caratinga, MG, Brazil.

<p>(A) Changes observed in the epidermis were intense acanthosis (AC) and papillomatosis (PL). Pearl corneas can also be seen (black arrow). Finger-like projections of epidermis into the dermis layer, papillomatosis (PL) Bar = 32 µm, (B) Higher magnification shows thickening of the spinous (acanthosis) layer due to proliferation of epidermal cells (arrowhead) leading to papillomatosis (PL). Bar = 16 µm, (C) Higher magnification showing the inflammatory infiltrate of mononuclear cells (plasma cells, macrophages and lymphocytes) in the dermis. Note Langhans-type giant cell formation, but without a typical granuloma formation (arrowhead). Bar = 16 µm. (D) Eosinophilic necrotic area in the dermis with fragmented collagen fibers resembling fibrinoid necrosis (arrowheads) Bar = 64 µm. Hematoxylin-eosin staining. Epithelium (Ep), Dermis (De), Papillomatosis (PL).</p

Resumos em andamento - Educação

Resumos em andamento - Educaçã

Resumos em andamento - Educação

Resumos em andamento - Educaçã