Comparative study of direct and indirect immunofluorescence for diagnosis of canine pemphigus foliaceus / Estudo comparativo da imunofluorescência direta e indireta para o diagnóstico do pênfigo foliáceo canino

Pemphigus foliaceus (PF) is the most common autoimmune skin disease in dogs. It is characterized by pustules, erosions, and crusts which occur due to the presence of autoantibodies that target intercellular adhesion. Histopathological examination is considered the gold standard pattern in the diagnosis, but may sometimes be inconclusive, especially when the characteristic findings are not identified. New diagnostic tests are continuously being developed and immunofluorescence assays, could be a valuable alternative diagnostic tool. This study aimed to evaluate the applicability of direct and indirect immunofluorescence (DIF and IIF) tests for the diagnosis of canine PF. Twenty eight dogs were divided into two groups: Group I with 14 dogs with PF and Group II (control) with 14 dogs with Superficial pyoderma (differential diagnoses of PF). All animals were submitted to skin biopsy to histopathological and DIF. Blood samples were collected to assess IIF. Comparing the DIF results against the histopathology test, there was an agreement of 75% (9/12) with a Kappa index of 0.77 (P<0.001). Considering IIF, the agreement was 100% (14/14), with a Kappa index of 1.0 (P<0.001). We conclude that DIF and IIF are highly effective and were useful and effective complementary examination tests for an improvement in the diagnosis of canine PF.(AU)

O pênfigo foliáceo (PF) é considerado uma das doenças tegumentares autoimunes mais frequentes em cães. Clinicamente, caracteriza-se pela presença de pústulas, erosões e crostas. O exame histopatológico é considerado o teste diagnóstico de eleição, porém pode se mostrar inconclusivo, sobretudo quando os achados característicos da doença não são observados. Novas ferramentas diagnósticas têm sido desenvolvidas e os testes de imunofluorecência são uma valiosa alternativa. Este estudo teve como objetivo avaliar a aplicabilidade das reações de imunofluorescência direta (IFD) e indireta (IFI) para o diagnóstico do PF canino. Vinte e oito cães foram divididos em dois grupos: grupo I com 14 cães com PF e grupo II (controle) com 14 cães com piodermite superficial (um dos principais diagnósticos diferenciais do PF). Todos os animais foram submetidos à biópsia cutânea, seguida de exame histopatológico e IFD. Amostras de sangue foram coletadas para realização da IFI. Comparando-se os valores de IFD com o histopatológico, obtiveram-se valores de concordância de 75% (9/12), com índice Kappa de 0,77 (P<0,001). Já na IFI, a concordância foi de 100% (14/14), com índice Kappa de 1,0 (P<0,001). Concluiu-se, então, que a IFD e a IFI apresentaram excelentes resultados e podem ser consideradas novas alternativas diagnósticas do PF canino.(AU)

Mutational status of naevus-associated melanomas.

BACKGROUND: The origin of melanoma has always been a debated subject, as well as the role of adjacent melanocytic naevi. Epidemiological and histopathological studies point to melanomas arising either de novo or from a naevus. OBJECTIVES: To evaluate the presence of mutations in genes from well-known melanomagenesis pathways in a large series of naevus-associated melanomas. MATERIALS AND METHODS: Sixty-one melanomas found in association with a pre-existing naevus were microdissected, after careful selection of cell subpopulations, and submitted to Sanger sequencing of the BRAF, NRAS, c-KIT, PPP6C, STK19 and RAC1 genes. Each gene was evaluated twice in all samples by sequencing or by sequencing and another confirmation method, allele-specific fluorescent polymerase chain reaction (PCR) and capillary electrophoresis detection or by SNaPshot analysis. Only mutations confirmed via two different molecular methods or twice by sequencing were considered positive. RESULTS: The majority of cases presented concordance of mutational status between melanoma and the associated naevus for all six genes (40 of 60; 66.7%). Nine cases presented concomitant BRAF and NRAS mutations, including one case in which both the melanoma and the adjacent naevus harboured V600E and Q61K double mutations. In two cases, both melanoma and associated naevus located on acral sites were BRAF mutated, including an acral lentiginous melanoma. CONCLUSIONS: To our knowledge this is the largest naevus-associated melanoma series evaluated molecularly. The majority of melanomas and adjacent naevi in our sample share the same mutational profile, corroborating the theory that the adjacent naevus and melanoma are clonally related and that the melanoma originated within a naevus.

Acute Generalized Exanthematous Pustulosis Induced by Cefepime: A Case Report.

Acute generalized exanthematous pustulosis (AGEP) is a rare cutaneous rash characterized by widespread sterile nonfollicular pustules. Cefepime is a fourth generation cephalosporin, used to treat severe infections. A 67-year-old man was admitted with acute gastroenterocolitis. On the seventh day, the patient developed a nosocomial pneumonia and cefepime was initiated. On the fourth day of cephalosporin treatment, he presented with a maculopapular, pruritic eruption affecting the face, neck, abdomen and limbs. One day later he developed disseminated pustular lesions and his temperature was 37°C. Laboratory analysis evidenced leukocytosis and skin biopsy showed subcorneal pustule, edema in the papillary dermis, perivascular inflammatory infiltrate consisting of neutrophils, leukocytoclasia and red cell extravasation in the epidermis. Cefepime was suspended and within 4 days the non-follicular pustules cleared following a desquamation. AGEP is a disease attributed to a variety of causes, but in 90% of the cases it is due to an adverse drug reaction. Antibiotics are implicated in 80% of these cases, mostly penicillins and macrolides. There are few cases associated with cephalosporins. It is very important to consider AGEP in cases of acute pustular rashes and drugs should be investigated as causative agents.

Dermatite micobacteriana atípica em gato: relato de caso / Atypical mycobacterial dermatitis in cat: a case report

Relata-se, pela primeira vez no Brasil, um caso de dermatite decorrente de infecção por micobactéria atípica do complexo Mycobacterium fortuitum-peregrinum, em espécie felina, sem raça definida, fêmea, com cinco anos de idade. Há oito meses, evoluía com lesões maculares equimóticas, nodulares, erosadas, ulceradas, acompanhadas de fístulas exsudativas, com intenso prurido e algia. Evidenciou-se a presença de micobactéria do complexo Mycobacterium fortuitum-peregrinum (grupo IV de Runyon ) identificada após evidenciação histopatológica, cultivo bacteriano e por testes bioquímicos. Após dois meses de terapia sistêmica com enrofloxacina (5mg/kg/Bid/VO) e tópica (triclosan e rifamicina) houve involução das lesões, com efeitos colaterais discretos.

A case of dermatitis caused by atypical mycobateria of Mycobacterium fortuitum peregrinum complex was observed for the first time in Brazil. A five-year-old female mixed breed cat had a dermatitis process which had started eight months before. Lesions were characterized by macules, nodules, erosions, ulcers and exsudative fistulas, with intensive pruritus and pain. It had failed to respond to clinical treatment and surgical excision. The diagnosis was based on history, physical and dermatologic examination and complementary tests (cytologic, bacterioscopic, bacterial culture, histopathological, hemathological, ultrasonographic, radiographic and electrocardiographic). The presence of mycobacteria of Mycobacterium fortuitum-peregrinum complex (group IV of Runyon) was observed and identified after histopathological evidence, bacterial culture and biochemical tests. After two months of systemic therapy with enrofloxacin (5mg/kg, orally/twice a day) and topic treatment with triclosan and rifamicin, rapid improvement of the clinical appearance of the lesions were observed with low incidence of side-effects.

Cutaneous T-cell lymphoma with HTLV-I infection: clinical overlap with adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) is a malignant proliferation of mature helper T lymphocytes,(1) and is caused by human T-lymphotropic virus type I (HTLV-I);(2) an HTLV-I infection endemic in the Caribbean, south-western Japan, South America and Africa.(3,4) Seroepidemiological studies suggest that it is also endemic in Brazil.(5) Although carriers of HTLV-I show polyclonal integration of virus in T lymphocytes, only patients with ATLL of various subtypes show monoclonal integration of HTLV-I in tumor cells.(6,7) Cutaneous T-cell lymphomas (CTCL) are a group of primary cutaneous lymphoproliferative diseases(8) with unknown etiology.(9) The two most common presentations of CTCL are mycosis fungoides (MF) and Sézary syndrome (SS).(10-13) However, both CTCL categories can easily resemble ATLL. Therefore, in HTLV-I endemic areas, differentiation between ATLL and CTCL must be performed, as they have different prognoses and treatment approaches.(14).

Dermoscopic examination of the nail bed and matrix.

Abstract Background Dermoscopy has furthered advances in the differential diagnosis of longitudinal melanonychia; however, fewer details observed in the nail, as compared to skin lesions, make interpretation difficult. Methods Ten cases of longitudinal melancholia, from several etiologies, were submitted to direct dermoscopic examination of the nail bed and matrix. Results We observed the presence of globules, streaks, and pigment network in the nail bed and matrix, which are dermoscopic features not seen in the nail plate. Conclusions This procedure enables visualization of dermascopic features not seen in the nail plate, making the diagnosis of melanocytic lesions easier.

Photoprotective effect of Pothomorphe umbellata root extract against ultraviolet radiation induced chronic skin damage in the hairless mouse.

In this study we evaluated the activity of Pothomorphe umbellata root extract on hairless mice chronically exposed to UVB radiation (76.5 mJ/cm(2), 4 days per week for 22 weeks). Mouse dorsal surfaces were treated topically with 20 mg/cm(2) of a carbomer 940 gel (vehicle) with or without P. umbellata root extract to a final concentration of 0.1%, for 2 h before irradiation. Another irradiated group received no topical treatment. A fourth group received no treatment and was not irradiated. Visible skin wrinkling was evaluated using a scale ranging from 0 to 4, where 0 corresponds to no skin modification, and 4 to the maximum visual skin alteration observed in our experiments. Histological measurements were carried out on standard haematoxylin & eosin stained sections. The mean distances between the outermost surface of the epidermis (excluding the stratum corneum) and the dermal-epidermal junction were determined by morphometric analysis. These distances were statistically increased in the irradiated control groups when compared to the nonirradiated control group and to the irradiated group using P. umbellata root extract. These data demonstrate that P. umbellata may be successfully used as a topical skin-protecting agent against the deleterious effects of UV radiation.

Detection and typing of human papillomavirus in cutaneous warts of patients infected with human immunodeficiency virus type 1.

BACKGROUND: Cutaneous warts are caused by human papillomavirus (HPV). To date, more than 120 different types of HPV are known, of which 80 have been completely characterized. Prevalence studies on types of HPV present in cutaneous warts have been carried out in immunocompetent individuals and immunosuppressed organ allograft recipients, but not in human immunodeficiency virus (HIV)-positive patients. OBJECTIVES: To determine the HPV types present in cutaneous warts of HIV-infected patients. METHODS: Twenty-five biopsies of cutaneous warts from HIV-infected patients and 14 samples from control non-HIV-infected patients were studied. HPV detection was performed by polymerase chain reaction using two sets of primers: MY09/MY11 and RK91. The type of HPV was determined by restriction fragment length polymorphism analysis and direct sequencing of the amplified products. RESULTS: HPV DNA was detected in 64% of cutaneous warts from HIV-infected patients and in 79% of samples from the control group. The HPV types identified in HIV-infected patients were: HPV 2 (38%), 57 (31%), 27 (12%), 6 (12%) and 7 (6%). HPV 2/27/57 predominated in both groups, being present in 81% of lesions from HIV-infected patients and 82% of samples from non-HIV-infected patients. HPV 6, a genital HPV type rarely found in cutaneous lesions, was detected in two warts from HIV-infected patients and in one lesion of the immunocompetent group. HPV 7, characteristically associated with butcher's warts, and recently detected in oral and perioral lesions of HIV-infected patients, was found for the first time in a non-facial lesion of an HIV-infected patient. CONCLUSIONS: This is the first study evaluating the prevalence of HPV types in cutaneous warts of HIV-infected patients and immunocompetent individuals in Brazil.

Criptococose canina: relato de caso / Canine ocular cryptococcosis: a case report

Descreve-se, pela primeira vez no Brasil, um caso de criptococose canina com acometimento oftalmo e dermatopático, com diagnóstico intra-vitam, em animal da raça Pastor Alemão, fêmea, com 24 meses de vida, criado em São Paulo, em contacto com outros cinco cães assintomáticos, que havia se infectado pelo contato com dejetos de pombos (Columba livia). Evoluia há 90 dias, com quadro tegumentar e ósseo, sintomas e lesões características, sendo, ainda, detectada forma assintomática de coriorretinite, de início unilateral. O diagnóstico foi estabelecido pelos dados da anamnese, dos exames físico, dermatológico e complementares (radiográfico, cultivo micológico, histopatologia de pele) tendo-se evidenciado e isolado cepa de Criptococcus neoformans var. neoformans. Após nove meses de terapia com itraconazol (9mg/kg/SID/VO) houve involução total do quadro, sem qualquer efeito adverso à droga.

Onicopatia associada a vasoconstrição de arteríolas dos dígitos

O artigo não apresenta resumo.

Lymphangitic sporotrichosis: an uncommon bilateral localization.

Sporotrichosis is a mycotic disease caused by cutaneous inoculation of the dimorphic fungus Sporothrix schenckii. The primary lesion can spread and often develop a unilateral lymphocutaneous lesions or, rarely, disseminated disease. We report a lymphangitic sporotrichosis case with ulcerated erythematous nodules distributed bilaterally on the posterior and medical aspect of the both legs, probably due to multiple inoculations. The treatment with oral potassium iodide was satisfactory.

Langerhans cell histiocytosis.

The authors present a rare case of Langerhans cell histiocytosis in a 31 year old female patient with vulvar, peri-anal and oral lesions, diabetes insipidus, pulmonary skin and bone infiltrations. Skin biopsy immunohistochemistry presented positive S100 protein and vimentin, but the diagnosis was done with the demonstration of Birbeck granules with electronic microscopy. The treatment was based on systematical chemotherapy although vulvar lesion has a bad response to chemotherapy.

Paracoccidioidomycosis: an uncommon localization in the scrotum.

Paracoccidioidomycosis is a systemic fungal infection caused by the thermally dimorphic fungus Paracoccidioides brasiliensis. The authors present a case of a 49-year-old man who developed verrucous lesions on nasal mucosa and on genital localization (inguinal and scrotal), without signs of systemic disease. Direct mycological examination, culture on Sabouraud glucose medium, and biopsy were positive for P. brasiliensis. The interest of this case is the genital localization which is uncommon in this infection. Moreover, there are few cases described in the literature.