The spleen is the graveyard of CD4+ cells in patients with immunological failure of visceral leishmaniasis and AIDS.

BACKGROUND: Visceral leishmaniasis (VL), or kala-azar, is a common comorbidity in patients with AIDS in endemic areas. Many patients continue to experiences relapses of VL despite virological control, but with immunological failure. These patients remain chronically symptomatic with hypersplenism, for example with anemia, leukopenia, and thrombocytopenia, and are at risk of severe co-infection due to low CD4+ count. Therefore, in this study, splenectomized patients with VL and HIV infection were investigated to understand why the CD4+ count fails to recover in these patients, evaluating the importance of spleen mass for hypersplenism and immunological failure. METHODS: From a retrospective open cohort of 13 patients who had previously undergone splenectomy as salvage therapy for relapsing VL, 11 patients with HIV infection were investigated. This study compared the patients' complete blood cell count (CBC) and CD4+ and CD8+ cell counts before and after splenectomy with respect to spleen weight. RESULTS: CBC was substantially improved after splenectomy, indicating hypersplenism. However, to the best of our knowledge, this is the first study to show that spleen mass is strongly and negatively correlated with CD4+ cell count (ρ = -0.71, P = 0.015). CONCLUSIONS: This finding was unexpected, as the spleen is the most extensive lymphoid tissue and T-lymphocyte source. After reviewing the literature and reasoning, we hypothesized that the immunological failure was secondary to CD4+ loss initially by apoptosis in the spleen induced by productive HIV infection and, subsequently, by pyroptosis sustained by parasitic infection in spleen macrophages.

IGF-1 overexpression improves mesenchymal stem cell survival and promotes neurological recovery after spinal cord injury.

BACKGROUND: Survival and therapeutic actions of bone marrow-derived mesenchymal stem cells (BMMSCs) can be limited by the hostile microenvironment present during acute spinal cord injury (SCI). Here, we investigated whether BMMSCs overexpressing insulin-like growth factor 1 (IGF-1), a cytokine involved in neural development and injury repair, improved the therapeutic effects of BMMSCs in SCI. METHODS: Using a SCI contusion model in C57Bl/6 mice, we transplanted IGF-1 overexpressing or wild-type BMMSCs into the lesion site following SCI and evaluated cell survival, proliferation, immunomodulation, oxidative stress, myelination, and functional outcomes. RESULTS: BMMSC-IGF1 transplantation was associated with increased cell survival and recruitment of endogenous neural progenitor cells compared to BMMSC- or saline-treated controls. Modulation of gene expression of pro- and anti-inflammatory mediators was observed after BMMSC-IGF1 and compared to saline- and BMMSC-treated mice. Treatment with BMMSC-IGF1 restored spinal cord redox homeostasis by upregulating antioxidant defense genes. BMMSC-IGF1 protected against SCI-induced myelin loss, showing more compact myelin 28 days after SCI. Functional analyses demonstrated significant gains in BMS score and gait analysis in BMMSC-IGF1, compared to BMMSC or saline treatment. CONCLUSIONS: Overexpression of IGF-1 in BMMSC resulted in increased cell survival, immunomodulation, myelination, and functional improvements, suggesting that IGF-1 facilitates the regenerative actions of BMMSC in acute SCI.

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.

Current distribution pattern of biopsy-proven glomerular disease in Salvador, Brazil, 40 years after an initial assessment.

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.

Transplantation of bone marrow mononuclear cells reduces mortality and improves renal function on mercury-induced kidney injury in mice.

OBJECTIVE: Recent studies have demonstrated the therapeutic effects of bone marrow-derived cells in tissue regeneration. The aim of this study was to investigate the effects of bone marrow mononuclear cell (BMMC) transplantation in a mouse model of acute renal failure (ARF) induced by mercuric chloride. METHODS: BMMC was isolated from male BALB/c mice and injected into female mice treated with a lethal dose (LD90) of mercuric chloride. Survival rate, histopathological analysis, and assessment of urea, creatinine, sodium, potassium, and mercury levels were carried out. RESULTS: Cellular therapy with BMMC significantly reduced the mortality induced by mercuric chloride (p < 0.05). This finding correlated with a decrease in serum levels of urea (p = 0.04) and potassium (p < 0.01). However, no differences in renal morphology were observed when BMMC-treated and control group were compared. CONCLUSION: Transplanted BMMC improve renal function and reduce mortality and, therefore, may represent a new therapeutic alternative to treat ARF.

Acute tubular necrosis and renal failure in patients with glomerular disease.

Renal failure is common in patients with glomerular disease. Although renal failure may result from the glomerular lesion itself, it is also observed in patients with minimal glomerular alterations. Degenerative changes and necrosis of the tubular epithelium are common findings in kidney biopsies from these patients. The aim of this work is to examine the association between acute tubular necrosis (ATN) and renal failure in patients with glomerulopathy and to estimate the relationship between the degree of ATN and renal failure in these patients. Data on age, sex, presence of nephrotic syndrome, and renal failure were recorded for 149 patients, who underwent a renal biopsy for the diagnosis of glomerulopathy. The biopsies were reviewed, and ATN, when present, was classified as one of four grades depending on its intensity. The mean age of the patients was 21 ± 16 years. Eighty patients (54%) were male, 43 (42%) had renal failure, 104 (72%) had nephrotic syndrome, and 66 (45%) had minimal change disease or focal segmental glomerulosclerosis. ATN was present in 115 (77%) patients. The frequency of renal failure was directly correlated with the intensity of ATN [odds ratio (OR) of 26.0 for patients with grade 2 lesions and OR of 45.5 for patients with grade 3 lesions]. ATN is a common finding in the biopsies of patients with glomerulopathy. The severity of ATN is directly associated with the frequency of renal failure in these patients.

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%) 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.

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.

Challenges in clinical-pathologic correlations: acute tubular necrosis in a patient with collapsing focal and segmental glomerulosclerosis mimicking rapidly progressive glomerulonephritis.

Herein, we report a case of acute kidney injury (AKI) due to diarrhea-induced acute tubular necrosis (ATN) in a patient with nephrotic syndrome secondary to biopsy-proven collapsing focal and segmental glomerulosclerosis (FSGS). The clinical picture mimicked rapidly progressive glomerulonephritis (RPGN) and motivated pulse therapy with methylprednisolone and cyclophosphamide. The case presentation is followed by a brief overview of the epidemiology of AKI in nephrotic syndrome as well as a discussion of its risk factors and potential mechanisms involved.

Semiquantitative and semi-automated morphometric evaluation of chronic lesions in renal biopsies.

Chronic lesions in renal biopsies are a well recognized prognostic factor for renal diseases, including lupus nephritis. The methods used for assessment of chronic lesions are, however, largely based on semiquantitative evaluation and may lead to poor reproducibility. Interobserver variation is particularly important in lupus nephritis, in which acute and chronic lesions may occur simultaneously. In this study we tested the reproducibility of chronic lesion assessment performed by three pathologists, two with specific training in renal pathology, using 20 renal biopsies and a standard semiquantitative method. In a second experiment, we evaluated the reproducibility of chronic lesion assessment in 33 biopsies of lupus nephritis by the two nephropathologists. The semiquantitative estimated values were compared with those from a previously proposed morphometric method for quantification of chronic lesions in renal biopsies. Although correlations were observed among the estimated values, there was a wide range of variation when semiquantitative methods were used. In particular, activity and chronicity indices of lupus nephritis were poorly reproducible. In contrast, use of a morphometric score, although not eliminating interobserver variability, led to better reproducibility of estimated values than that obtained with semiquantitative methods.

Is there a relationship between the detection of human herpesvirus 8 and Epstein-Barr virus in Waldeyer's ring tissues?

OBJECTIVE: Human herpesvirus 8 (HHV-8) and Epstein-Barr virus (EBV) are human pathogens associated to a number of neoplasms, including tumors of the Waldeyer's ring. Both viruses have been previously detected by in situ methods in tonsils and adenoids from children. HHV-8 was found in 6.8% of the cases and EBV in about one third of the cases. As they belong to the same gamma-herpesvirus subfamily and share some biological characteristics, it is of medical interest to further explore their possible relationship in the Waldeyer's ring, an issue not yet addressed in the specialized literature. The purpose of the present study is to compare the presence of EBV by in situ hybridization (ISH) in tonsils and adenoids from children up to 14 years of age in cases previously shown to be positive and negative for HHV-8. METHODS: Paraffin wax-embedded sections consisting of 38 tonsils and two adenoids from 40 patients were analyzed. HHV-8 was detected by ISH, using the T1-1 probe for the viral mRNA. EBV was also detected by ISH, using the EBER probe. Both probes and the detection systems were provided by Novocastra. RESULTS: HHV-8 was detected in 19 tonsils and one adenoid. The other 19 tonsils and one adenoid taken from the HHV-8-negative group were selected by pairing age and gender of patients with the HHV-8-positive group. In both groups EBV was detected in 13 cases and was negative in other 7. CONCLUSION: Although both viruses are related in many aspects, some biological and epidemiological features differ. This is reflected in the present results, as EBV is similarly detected in the groups negative and positive for HHV-8, favoring different mechanisms of spread.

A standardized cytological and immunochemical method for the analysis of fine-needle spleen aspirates: assessment of leukocyte population changes in canine visceral leishmaniosis.

A method for the evaluation of splenic cellularity using samples collected by fine-needle aspirative biopsy was standardized in this work. The procedure includes erythrocyte lysing, preparation of cytospin films and staining by histochemical and immunocytochemical techniques. The cellular profiles of spleen preparations were compared with those observed in peripheral blood samples subjected to the same procedure. Two groups were compared, one consisting of 14 healthy uninfected and the other of 15 polysymptomatic Leishmania chagasi/infantum-infected dogs, from an endemic area for visceral leishmaniosis. Cell populations were identified by conventional hematoxilin-eosin and Wright' stainings, and by immunocytochemistry using monoclonal antibodies against canine CD45RA and CD45RB, phagocytes and a pan-leukocyte antigen. Larger neutrophil (P < 0.0001) and monocyte/macrophage (P = 0.0036) relative counts and lower lymphocyte relative counts (P < 0.0001) were found in the spleen, and not in the blood, of the animals with leishmaniosis than in those of the healthy animals. The proportions of CD45RB+ cells were higher, and of CD45RA+ cells were lower, both in the spleen and in the blood of animals with leishmaniosis than in those of healthy dogs (P < 0.05). Additionally, hematoxilin-eosin-stained cytospins of spleen aspirates from Leishmania-infected animals permitted the easy visualization of amastigote forms inside phagocytes, under light microscopy.

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%; in lymph node cultures it was 25%. 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.

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.