Upregulation of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in renal tissue in severe dengue in humans: Effects on endothelial activation/dysfunction

Abstract INTRODUCTION: Dengue is an important mosquito-borne disease in tropical and subtropical regions. Adhesion molecules have not been systematically characterized in the renal tissue of patients with severe dengue (SD). The objective of this study was to detect viral antigens in samples from patients that evolved with SD, correlating with the expression of ICAM-1, VCAM-1, VE-cadherin, and E-selectin to contribute to a better understanding of the pathophysiology of SD. METHODS: Kidney specimens from patients with SD were selected according to clinical and laboratorial data and submitted to histological and immunohistochemistry analysis. A semiquantitative evaluation was performed considering positive immunostaining in 20 glomeruli. RESULTS: Viral antigens were mainly detected in distal tubules. The intense immunostaining of VCAM-1 and ICAM-1 was observed. The expression of E-selectin was discrete, and VE-cadherin expression varied from mild to moderate. VCAM-1 was slightly intense in the glomerular capsule; the expression of ICAM-1 was diffuse. E-selectin was diffuse, and VE-cadherin varied from mild to moderate. The most frequent histological findings were glomerular congestion, mild glomerulitis, acute renal injury, and glomerular atrophy. CONCLUSIONS: The results appear to demonstrate an imbalance between vascular endothelial permeability regulating events in renal lesions in SD. The increase in the expression of ICAM-1 and VCAM-1 is an in-situ indicator of higher permeability with a consequent influx of cells favoring the inflammation of the endothelium. These molecules are important in the pathophysiology of the disease and provide the possibility of developing new markers for the evaluation, clinical follow-up, and therapeutic response of patients with SD.

IgA Nephropathy in Salvador, Brazil. Clinical and laboratory presentation at diagnosis / Nefropatia por IgA em Salvador, Brasil. Apresentação clínica e laboratorial no momento do diagnóstico

ABSTRACT Introduction: IgA nephropathy (IgAN) is the most prevalent primary glomerulopathy in the world, but great variation is reported in different countries. In Brazil, the reported prevalence is high in the Southeastern States and low in Salvador, Bahia State, Brazil. Objectives: This study investigated the clinical and histological patterns of patients with IgAN in Salvador, Brazil. Methods: This is a descriptive study that included all patients with a diagnosis of IgAN performed in native kidney biopsies collected from referral nephrology services of public hospitals in Salvador between 2010 and 2015. Results: Thirty-two cases of IgAN were identified, corresponding to 6% of primary glomerulopathies. There was a slight male predominance (56%) and the median age was 30 [22-40] years. Hematuria was present in 79%, non-nephrotic proteinuria was present in 61%, and hypertension was present in 69% of patients. Segmental sclerosis (S1 lesions) was present in 81% of cases, and chronic tubulo-interstitial lesions (T1 and T2 lesions) were present in 44% of cases. Patients with M1 and T2 MEST-C scores exhibited higher serum urea and creatinine than other patients. Conclusion: The prevalence of IgAN was lower in Salvador than other regions of Brazil. Chronic histological lesions and laboratory markers of severe disease were frequent. M1 and T2 MEST-C scores were correlated with markers of renal dysfunction.

RESUMO Introdução: A nefropatia por IgA (NIgA) é a glomerulopatia primária mais prevalente no mundo, mas grande variação é relatada em diferentes países. No Brasil, a prevalência relatada é alta nos estados do Sudeste e baixa em Salvador, Bahia, Brasil. Objetivos: Este estudo investigou os padrões clínicos e histológicos de pacientes com NIgA em Salvador, Brasil. Métodos: Trata-se de um estudo descritivo que incluiu todos os pacientes com diagnóstico de NIgA, realizados em biópsias de rins nativos, coletados nos serviços de referência em nefrologia dos hospitais públicos de Salvador, entre 2010 e 2015. Resultados: Foram identificados 32 casos de NIgA, correspondendo a 6% de glomerulopatias primárias. Houve uma ligeira predominância do sexo masculino (56%) e a mediana da idade foi de 30 [22-40] anos. Hematúria esteve presente em 79%, proteinúria não nefrótica esteve presente em 61% e hipertensão esteve presente em 69% dos pacientes. A esclerose segmentar (lesão S1) estava presente em 81% dos casos, e lesões túbulo-intersticiais crônicas (lesões T1 e T2) estavam presentes em 44% dos casos. Pacientes com escores M1 e T2 MEST-C exibiram maior ureia e creatinina séricas que outros pacientes. Conclusão: A prevalência de NIgA foi menor em Salvador do que em outras regiões do Brasil. Lesões histológicas crônicas e marcadores laboratoriais de doença grave foram frequentes. Os escores M1 e T2 MEST-C foram correlacionados com marcadores de disfunção renal.

Current distribution pattern of biopsy-proven glomerular disease in Salvador, Brazil, 40 years after an initial assessment / Padrão de distribuição atual da doença glomerular documentada por biópsia em Salvador, Brasil, 40 anos após a avaliação inicial

Abstract Introduction: A report on the prevalence of glomerular disease diagnosed via renal biopsy in Salvador, BA, Brazil was published in 1973 and showed a predominance of membranoproliferative glomerulonephritis, which was frequently associated with hepatosplenic schistosomiasis. Objective: In this study, we investigate the potential changes in the distribution of glomerular diseases after a period of important epidemiological transition in Brazil. Methods: Pathology reports of all patients subjected to kidney biopsy from 2003 to 2015 in a referral nephrology service were reviewed. Clinical, laboratorial and pathological diagnoses were collected for analysis. Histological slides of the biopsies performed between 2003 and 2006 were reviewed to examine the accuracy of the estimates based on the pathology reports. Results: Among the biopsies performed during the time period, 1,312 met the inclusion criteria for the study. Focal and segmental glomerulosclerosis was the most prevalent diagnosis, followed by lupus nephritis. However, a trend toward a decrease in the prevalence of focal and segmental glomerulosclerosis was detected (p < 0.05), and an increase in lupus (p < 0.0001) and membranous glomerulonephritis (p < 0.005) was observed. Conclusion: The data presented herein suggest the occurrence of changes in the distribution of nephrological diseases in Salvador, Brazil. The disease that was most prevalent shifted from membranoproliferative glomerulonephritis to focal and segmental glomerulosclerosis from 1975 to 2006 and from focal and segmental glomerulosclerosis to lupus nephritis from 2006 to 2015.

Resumo Introdução: um relatório sobre a prevalência de glomerulopatia diagnosticada por biópsia renal em Salvador foi publicado em 1973, demonstrando o predomínio de glomerulonefrite membranoproliferativa, frequentemente associada a esquistossomose hepatoesplênica. Objetivo: no presente estudo, investigamos as possíveis mudanças na distribuição das glomerulopatias após um período de importantes transições epidemiológicas no Brasil. Métodos: foram revisados todos os relatos de pacientes submetidos a biópsia renal de 2003 a 2015 em um serviço de referência em nefrologia. Diagnósticos clínicos, laboratoriais e patológicos foram colhidos para análise. Lâminas histológicas das biópsias executadas entre 2003 e 2006 foram revisadas para avaliar a precisão das estimativas baseadas nos laudos anatomopatológicos. Resultados: entre as biópsias realizadas durante o período em questão, 1.312 satisfizeram os critérios de inclusão do estudo. Glomeruloesclerose segmentar e focal foi o diagnóstico mais prevalente, seguido de nefrite lúpica. Entretanto, foi detectada tendência de queda na prevalência da glomeruloesclerose segmentar e focal (p < 0,05) e de elevação nos casos de lúpus (p < 0,0001) e glomerulonefrite membranosa (p < 0,005). Conclusão: os dados apresentados neste estudo sugerem a ocorrência de mudanças na distribuição das doenças nefrológicas em Salvador. A doença mais prevalente passou de glomerulonefrite membranoproliferativa para glomeruloesclerose segmentar e focal de 1975 a 2006 e de glomeruloesclerose segmentar e focal para nefrite lúpica de 2006 a 2015.

Inflammation in disseminated lesions: an analysis of CD4+, CD20+, CD68+, CD31+ and vW+ cells in non-ulcerated lesions of disseminated leishmaniasis

Disseminated leishmaniasis (DL) differs from other clinical forms of the disease due to the presence of many non-ulcerated lesions (papules and nodules) in non-contiguous areas of the body. We describe the histopathology of DL non-ulcerated lesions and the presence of CD4-, CD20-, CD68-, CD31- and von Willebrand factor (vW)-positive cells in the inflamed area. We analysed eighteen biopsies from non-ulcerated lesions and quantified the inflamed areas and the expression of CD4, CD20, CD68, CD31 and vW using Image-Pro software (Media Cybernetics). Diffuse lymphoplasmacytic perivascular infiltrates were found in dermal skin. Inflammation was observed in 3-73% of the total biopsy area and showed a significant linear correlation with the number of vW+ vessels. The most common cells were CD68+ macrophages, CD20+ B-cells and CD4+ T-cells. A significant linear correlation between CD4+ and CD20+ cells and the size of the inflamed area was also found. Our findings show chronic inflammation in all DL non-ulcerated lesions predominantly formed by macrophages, plasmacytes and T and B-cells. As the inflamed area expanded, the number of granulomas and extent of the vascular framework increased. Thus, we demonstrate that vessels may have an important role in the clinical evolution of DL lesions.

Modelo experimental de isquemia: reperfusão intestinal por clampeamento de aorta abdominal em ratos Wistar / Experimental model of mesenteric ischemia: reperfusion by abdominal aorta clamping in Wistar rats

OBJETIVO: desenvolver um modelo experimental de isquemia global normotérmica transitória capaz de demonstrar os tempos de isquemia e reperfusão necessários para desenvolvimento de lesão de isquemia/reperfusão em intestinos delgados de ratos Wistar através clampeamento de aorta abdominal suprarrenal. MÉTODOS: Vinte ratos Wistar adultos machos, pesando entre 250 e 350g, foram distribuídos aleatoriamente em cinco grupos, com quatro ratos cada, e submetidos a tempos crescentes de isquemia (0 - 30 - 45 - 60 - 90 minutos). Dentro de cada grupo, à exceção do grupo controle, dois ratos foram submetidos à 60 minutos de reperfusão e dois à 90 minutos. Após os procedimentos, procedeu-se análise histológica através de medição de áreas de necrose. RESULTADOS: O grau de necrose intestinal variou de 15 a 54% (p=0,0004). Houve tendência de aumento progressivo no grau de lesão relacionado ao aumento no tempo de isquemia, contudo, os maiores graus de lesão foram observados nos menores tempos de reperfusão. A análise do coeficiente de variação de necrose entre os dez grupos de isquemia/reperfusão demonstrou diferença estatisticamente significante em 15 postos, sendo 13 relacionados ao grupo controle. CONCLUSÃO: O modelo foi capaz de demonstrar os tempos necessários para que ocorra lesão de isquemia/reperfusão intestinal através de clampeamento aórtico e poderá servir como base para facilitar o desenvolvimento de estudos voltados para a compreensão deste tipo de lesão.

OBJECTIVE: To develop an experimental model of global normothermic ischemia able to demonstrate the transient ischemia and reperfusion periods required for development of ischemia/reperfusion injury in the small intestines of Wistar rats by clamping the abdominal aorta. METHODS: Twenty adult male Wistar rats weighing 250-350g were randomly divided into five groups with four rats each and submitted to increasing times of ischemia (0 - 30 - 45 - 60 - 90 minutes). Within each group, except the control one, two rats underwent 60 minutes of reperfusion and two 90 minutes. After the procedures, histological analysis was conducted by measurement of areas of necrosis. RESULTS: The degree of intestinal necrosis ranged from 15% to 54% (p = 0.0004). There was progressive increase in the degree of injury related to increase in ischemic time. However, greater degrees of injury were observed in the lowest times of reperfusion. The analysis of the coefficient of variation of necrosis among the ten groups of ischemia/reperfusion showed a statistically significant difference in 15 areas, 13 related to the control group. CONCLUSION: The model was able to show the periods required for the occurrence of ischemia/reperfusion injury by aortic clamping and can serve as a basis to facilitate the development of studies that aim at understanding this kind of injury.

Schistosomal glomerulopathy and changes in the distribution of histological patterns of glomerular diseases in Bahia, Brazil

Distinct patterns of glomerular lesions, including membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis, are associated with infection by Schistosoma mansoni or Schistosoma japonicum. Evidence suggests that immune complex deposition is the main mechanism underlying the different forms of schistosomal glomerulonephritis and that immune complex deposition may be intensified by portal hypertension. The relationship between focal segmental glomerulosclerosis and schistosomiasis remains poorly understood. A clinicopathologic classification of schistosomal glomerulopathies was proposed in 1992 by the African Association of Nephrology. In Brazil, mass treatment with oral medications has led to a decrease in the occurrence of schistosomal glomerulopathy. In a survey of renal biopsies performed in Salvador, Brazil, from 2003-2009, only 24 (4 percent) patients were identified as positive for S. mansoni infection. Among these patients, only one had the hepatosplenic form of the disease. Focal segmental glomerulosclerosis was found in seven patients and membranoproliferative glomerulonephritis was found in four patients. Although retrospective studies on the prevalence of renal diseases based on kidney biopsies may be influenced by many patient selection biases, a change in the distribution of glomerulopathies associated with nephrotic syndrome was observed along with a decline in the occurrence of severe forms of schistosomiasis.

An experimental protocol for the establishment of dogs with long-term cellular immune reactions to Leishmania antigens

Domestic dogs are considered to be the main reservoirs of zoonotic visceral leishmaniasis. In this work, we evaluated a protocol to induce Leishmania infantum/Leishmania chagasi-specific cellular and humoral immune responses in dogs, which consisted of two injections of Leishmania promastigote lysate followed by a subcutaneous inoculation of viable promastigotes. The primary objective was to establish a canine experimental model to provide positive controls for testing immune responses to Leishmania in laboratory conditions. After inoculation of viable promastigotes, specific proliferative responses of peripheral blood mononuclear cells (PBMCs) to either Leishmania lysate or recombinant proteins, the in vitro production of interferon-γ by antigen-stimulated PBMCs and a significant increase in circulating levels of anti-Leishmania antibodies were observed. The immunized dogs also displayed positive delayed-type hypersensitivity reactions to Leishmania crude antigens and to purified recombinant proteins. An important finding that supports the suitability of the dogs as positive controls is that they remained healthy for the entire observation period, i.e., more than seven years after infection. Following the Leishmania antigen lysate injections, the infection of dogs by the subcutaneous route appears to induce a sustained cellular immune response, leading to an asymptomatic infection. This provides a useful model for both the selection of immunogenic Leishmania antigens and for immunobiological studies on their possible immunoprotective activities.

Comparison between splenic and lymph node aspirations as sampling methods for the parasitological detection of Leishmania chagasi infection in dogs

The sensitivities of spleen and lymph node cultures for the diagnosis of canine visceral leishmaniasis were compared in 64 anti-Leishmania antibody positive dogs from an endemic area in Brazil. The sensitivity of spleen cultures for Leishmania detection was 97.9 percent; in lymph node cultures it was 25 percent. Positive spleen culture was more frequent (p = 0.048, Fisher's exact probability test) in symptomatic (28 out of 33 animals) than in asymptomatic animals (19 out of 31 animals). These results support the use of spleen instead of lymph node aspiration as the choice method for the parasitological diagnosis of the infection.