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Introduction: Dengue virus (DENV), the etiologic agent of dengue fever illness, represents a global public health concern, mainly in tropical and subtropical areas across the globe. It is well known that this acute viral disease can progress to severe hemorrhagic stages in some individuals, however, the immunopathogenic basis of the development of more severe forms by these patients is yet to be fully understood. Objective: In this context, we investigated and characterized the histopathological features as well as the cytokine profile and cell subpopulations present in liver tissues from three fatal cases of DENV in children. Methods: Hematoxylin and Eosin, Periodic Acid Schiff and Picro Sirius Red staining were utilized for the histopathological analysis. Immunohistochemistry assay was performed to characterize the inflammatory response and cell expression patterns. Results: Vascular dysfunctions such as hemorrhage, vascular congestion and edema associated with a mononuclear infiltrate were observedin all three cases. Liver tissues exhibited increased presence of CD68+ and TCD8+ cells as well as high expression of MMP-9, TNF-a, RANTES, VEGFR-2 mediators. Viral replication was confirmed by the detection of NS3 protein. Conclusion: Taken together, these results evidenced key factors that may be involved in the development of severe alterations in liver tissues of children in response to DENV infection.

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Dengue viral (DENV) infections can lead to acute pancreatitis and associated tissue damage. This study examined the pancreas from two fatal cases of DENV for histopathological changes as well as for the detection of cytokines, and other inflammatory mediators. Tissue sections were prepared for examination by ultrastructural and histopathological techniques. Sections from the pancreas of non-infected individuals were prepared in parallel as a control. The presence of viral replication in macrophages was detected by co-staining for the proteins NS3 and CD68 by immunofluorescence. Immunohistochemistry was used to detect cells that expressed cytokines and inflammatory mediators to characterize the inflammatory response. Edema, acinar necrosis and fibrosis areas associated with a mononuclear infiltrate were found in infected tissues. The major site of virus replication appeared to be macrophages based on their exclusive presentation of the viral protein NS3. Pancreatic tissues from the infected individuals also displayed increased levels of high mobility group box-1, caspase-3, gelatinase B and tumor necrosis factor alpha compared to controls. The presence of virus replicating macrophages in the pancreas was associated with multiple changes in tissue structure that included elevated levels of cytokines and inflammatory markers that may differentiate acute pancreatitis due to DENV infections from other causes.

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Intrauterine transmission of the Chikungunya virus (CHIKV) during early pregnancy has rarely been reported, although vertical transmission has been observed in newborns. Here, we report four cases of spontaneous abortion in women who became infected with CHIKV between the 11th and 17th weeks of pregnancy. Laboratorial confirmation of the infection was conducted by RT-PCR on a urine sample for one case, and the other three were by detection of IgM anti-CHIKV antibodies. Hematoxylin and eosin (H&E) staining and an electron microscopy assay allowed us to find histopathological, such as inflammatory infiltrate in the decidua and chorionic villi, as well as areas of calcification, edema and the deposition of fibrinoid material, and ultrastructural changes, such as mitochondria with fewer cristae and ruptured membranes, endoplasmic reticulum with dilated cisterns, dispersed chromatin in the nuclei and the presence of an apoptotic body in case 1. In addition, by immunohistochemistry (IHC), we found a positivity for the anti-CHIKV antibody in cells of the endometrial glands, decidual cells, syncytiotrophoblasts, cytotrophoblasts, Hofbauer cells and decidual macrophages. Electron microscopy also helped in identifying virus-like particles in the aborted material with a diameter of 40-50 nm, which was consistent with the size of CHIKV particles in the literature. Our findings in this study suggest early maternal fetal transmission, adding more evidence on the role of CHIKV in fetal death.

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Mycobacterium haemophilum is a nontuberculous mycobacterium that causes localized or disseminated disease, mainly in immunocompromised hosts. We report the case of a 35-year-old HIV-infected woman who presented with several enlarging cutaneous lesions over the arms and legs. Histopathological examination revealed the diagnosis of a cutaneous mycobacterial disease. Mycobacterial analyses unveiled M. haemophilum infection. Six months after completion of a successful antimycobacterial treatment, she developed an immune reconstitution inflammatory syndrome (IRIS). This paradoxical relapse presented as tenderness, redness and swelling at the precise sites of the healed lesions and took place in the setting of significant recovery of the CD4 cell count (from 05 to 318 cells/mm 3 ). Microbiological analyses of these worsening lesions were negative, and they spontaneously remitted without the initiation of a novel antimycobacterial treatment cycle. M. haemophilum infection should always be considered as a cause of skin lesions in immunocompromised subjects. Physicians should be aware of the possibility of IRIS as a complication of successful antiretroviral therapy in HIV-infected patients with M. haemophilum infection.

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Dengue virus (DENV) infections may result in asymptomatic cases or evolve into a severe disease, which involves multiple organ failure. Renal involvement in dengue can be potentially related to an increased mortality. Aiming to better understand the role of DENV in renal injury observed in human fatal cases, post-mortem investigations were performed in four DENV-4 renal autopsies during dengue epidemics in Brazil. Tissues were submitted to histopathology, immunohistochemistry, viral quantification, and characterization of cytokines and inflammatory mediators. Probably due the high viral load, several lesions were observed in the renal tissue, such as diffuse mononuclear infiltration around the glomerulus in the cortical region and in the medullary vessels, hyalinosis arteriolar, lymphocytic infiltrate, increased capsular fibrosis, proximal convoluted tubule (PCT) damage, edema, PCT debris formation, and thickening of the basal vessel membrane. These changes were associated with DENV-4 infection, as confirmed by the presence of DENV-specific NS3 protein, indicative of viral replication. The exacerbated presence of mononuclear cells at several renal tissue sites culminated in the secretion of proinflammatory cytokines and chemokines. Moreover, it can be suggested that the renal tissue injury observed here may have been due to the combination of both high viral load and exacerbated host immune response.

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BACKGROUND: Dengue is the most important mosquito-borne viral disease in the world. Dengue virus infection may be asymptomatic or lead to undifferentiated fever, dengue fever with or without warning signs, or severe dengue. Lower respiratory symptoms are unusual and lung-imaging data in patients with dengue are scarce. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate lung changes associated with dengue infection, we retrospectively analyzed 2,020 confirmed cases of dengue. Twenty-nine of these patients (11 females and 18 males aged 16-90 years) underwent chest computed tomography (CT), which yielded abnormal findings in 17 patients: 16 patients had pleural effusion (the sole finding in six patients) and 11 patients had pulmonary abnormalities. Lung parenchyma involvement ranged from subtle to moderate unilateral and bilateral abnormalities. The most common finding was ground-glass opacity in eight patients, followed by consolidation in six patients. Less common findings were airspace nodules (two patients), interlobular septal thickening (two patients), and peribronchovascular interstitial thickening (one patient). Lung histopathological findings in four fatal cases showed thickening of the alveolar septa, hemorrhage, and interstitial edema. CONCLUSIONS/SIGNIFICANCE: In this largest series involving the use of chest CT to evaluate lung involvement in patients with dengue, CT findings of lower respiratory tract involvement were uncommon. When abnormalities were present, pleural effusion was the most frequent finding and lung involvement was often mild or moderate and bilateral. Extensive lung abnormalities are infrequent even in severe disease and when present should lead physicians to consider other diagnostic possibilities.

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Após a dissecção de cérebro de uma paciente em 1868, Charcot definiu uma evidência histopatológica mais assertiva para a esclerose múltipla (EM): "sclerose en plaque". Entretanto, mais de um século depois, poucos estudos examinando o substrato patológico específico de fenótipos clínicos diferentes da EM são encontrados na literatura. O objetivo deste estudo é uma revisão da literatura sobre achados post-mortem (autopsia, exame histopatológico e técnicas imuno-histoquímicas) em pacientes com EM. Utilizando os termos "autopsy", "necropsy", "pathology", "post-mortem" e "multiple sclerosis", a pesquisa foi desenvolvida sobre a literatura e recursos presentes no MEDLINE no período janeiro 1990 a agosto 2012. Artigos relevantes baseados em análise macro/microscópica das lesões da EM e o uso de técnicas imuno-histoquímicas (marcadores imunológicos e neurobiológicos) foram revistos. Tratados de patologia cirúrgica e neuropatologia em suas últimas edições foram também consultados. Além dos estudos no início dos anos 2000 que identificaram padrões diferentes de desmielinização em casos de autópsia, considerando a perda de mielina, a geografia e extensão das lesões, a destruição dos oligodendrócitos e a evidência do dano imunopatológico, estudos mais detalhados e baseados em aspectos anatomopatológicos e implicações patogênicas são raros. A maioria destes poucos e específicos estudos reportam que as lesões da EM tipicamente aparecem na substância branca, mas são também abundantes na substância cinza, heterogeneidade de lesões inter-paciente e homogeneidade intra-paciente, graus diferentes para perda de mielina e estágios de atividade, foco de atividade inflamatória que origina gliose fibrilar, distrofia de oligodendrócitos e densidade axonal central diminuída. Desmielinização é um importante indicador de progressão clínica e a remielinização pode ser incompleta ou decresce com a cronicidade da doença. A importância das lesões na substância branca de aparência normal e na substância cinzenta tem sido cada vez mais reconhecida em recentes estudos com técnicas imuno-histoquímicas. Não há ainda um consenso se as diferenças entre as formas clínicas são fundamentalmente quantitativas ou qualitativas em relação ao substrato patológico e mais estudos sobre autopsias utilizando exame histopatológico e técnicas modernas de imuno-histoquímica são necessários para dirimir esta questão. Um melhor entendimento sobre a heterogeneidade das lesões da esclerose múltipla proporcionará o desenvolvimento de métodos terapêuticos mais direcionados e eficazes.

After dissection of a female brain in 1868, Charcot outlined a more assertive histopathological evidence of Multiple Sclerosis: "sclerose en plaque". However, more than a century later, very few studies examining the specific underlying pathology of a defined MS clinical phenotype are found in literature. The purpose of this study is to provide a literature review of post-mortem findings (histopathology and immunohistochemical techniques) in MS patients. The literature in MEDLINE was searched from January 1990 to August 2012 using the terms "autopsy", "necropsy", "pathology", "postmortem" and "multiple sclerosis". Relevant papers based on macroscopic/microscopic analysis of the MS lesions and the use of broad spectrum of immunological and neurobiological markers (immunohistochemistry) were reviewed. Textbooks of Surgical Pathology and Neuropathology in latest editions were also consulted.Besides the studies in the early 2000s that identified different patterns of demyelination in autopsy cases, consider the myelin impairment, the geography and extension of lesions, the oligodendrocyte destruction and the evidence of immunopathological damage, more detailed studies based on anatomopathological aspects and pathogenic implications are rare. Most of these few specific studies reported that MS lesions typically appear in the white matter, but are also abundant in grey matter, inter-patient lesions heterogeneity with intra-patient homogeneity, different degree of myelin loss and stage of activity, focus of inflammatory activity that gives way to fibrillary gliosis, oligodendrocyte dystrophy and decreased central axonal density. Demyelination is an important pathological correlate of clinical progression and remyelination could be incomplete or decreases with disease chronicity. The importance of healthy-appearing white matter damage and grey matter demyelination has been increasingly recognized in recent studies using immunohistochemical techniques. There is still no consensus on whether the differences between the clinical forms of MS are fundamentally quantitative or qualitative in relation to the pathological substrate, and more detailed studies with data on autopsies is required to resolve this issue. A better understanding of the pathogenetic heterogeneity of MS lesions will lead the development of more effective treatment methods.

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Loiasis is a filarial disease transmitted by the Chrysops spp. tabanid flies in West and Central Africa. It is most commonly diagnosed by the clinical manifestations of Calabar swellings (transient localized inflammatory edema) or, most dramatically, by the appearance of a migrating worm through the conjunctival tissues or the bridge of the nose. We report the case of a 35-year-old resident in the city of Rio de Janeiro who displayed a moving Loa loa in the bulbar conjunctival tissue two years after returning from a six-month trip to Uganda. Surgical removal of the worm was performed.

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Loiasis is a filarial disease transmitted by the Chrysops spp. tabanid flies in West and Central Africa. It is most commonly diagnosed by the clinical manifestations of Calabar swellings (transient localized inflammatory edema) or, most dramatically, by the appearance of a migrating worm through the conjunctival tissues or the bridge of the nose. We report the case of a 35-year-old resident in the city of Rio de Janeiro who displayed a moving Loa loa in the bulbar conjunctival tissue two years after returning from a six-month trip to Uganda. Surgical removal of the worm was performed.

A loaíase é uma filaríase transmitida por tabanídeos (mutucas) do gênero Chrysops na África central e ocidental, comumente diagnosticada pela apresentação clínica de edema de Calabar (edema inflamatório transitório e localizado) ou, mais dramaticamente, pela migração de um verme adulto pelo tecido conjuntival ou asa do nariz. Descrevemos o caso clínico de um paciente do sexo masculino, 35 anos, residente no Rio de Janeiro, que se apresentou com um verme adulto de Loa loa migrando sobre o tecido conjuntival bulbar dois anos após retornar de uma viagem de seis meses de duração a Uganda. Procedeu-se a remoção cirúrgica do verme.

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BACKGROUND: A rubella mass vaccination campaign targeting 15-29-year-old women was performed in Brazil in 2001-2002. Rubella vaccination was contraindicated during pregnancy. A follow-up protocol was implemented for pregnant women who were vaccinated as well as their newborns. The risks of congenital rubella syndrome (CRS) and congenital rubella infection (CRI) after vaccination were assessed according to the pregnant women's immune status. METHODS: This was a prospective, noncontrolled study of pregnancy outcomes in women vaccinated against rubella in the state of Rio de Janeiro, including clinical and laboratory evaluations. RESULTS: Of 2292 reported pregnant women who were vaccinated, 1636 had known outcomes: there were 1577 newborns (96.4%), 52 miscarriages (3.2%), and 7 stillbirths (0.4%). Gestational age at vaccination was ≤ 5 weeks in 75% of the susceptible, vaccinated pregnant women. Nine newborns were positive for immunoglobulin M; 4 were born to susceptible pregnant women, for a 2.0% CRI rate (95% confidence interval, .5%-4.9%); 4 were born to vaccinated pregnant women with indeterminate or unknown status; and 1 had CRS, with a wild-type virus infection. CONCLUSIONS: The absence of vaccine-related CRS cases further supports recommendations to not interrupt a pregnancy exposed to rubella vaccine virus. Monitoring pregnancy outcomes and CRI with vaccine virus can distinguish between wild-type and vaccine virus infections, especially in situations of viral circulation.

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