Endophthalmitis: A Rare but Devastating Metastatic Bacterial Complication of Hemodialysis Catheter-Related Sepsis

There are many infectious complications related to vascular access in patients undergoing maintenance hemodialysis. We report two cases of endophthalmitis as a metastatic infection associated with a tunneled catheter and a temporary dual lumen catheter. Both patients were diabetic. A 61-year-old female on maintenance hemodialysis by a jugular tunnelized catheter during the past year was receiving parenteral antibiotics for catheter salvage due to fever episodes in the last 3 months. She was admitted to the hospital presenting pain, proptosis, conjunctival hyperemia, corneal infiltrate, and visual acuity of no light perception (NLP). A 51-year-old male recently undergoing hemodialysis by a temporary dual lumen catheter presented fever. His catheter was removed, but he was admitted to the hospital presenting fever, decreased vision, edema, and pain in his left eye. On examination, eyelid edema, conjunctival hyperemia, purulent secretion, hypopyon in the pupils, and visual acuity of NLP were verified. A diagnosis of endogenous endophthalmitis was made in both patients on clinical grounds and computed tomography. Evisceration of the left eye was the first option of treatment for both patients due to poor vision. Cultures of the eviscerated ocular globes showed Staphylococcus hemolyticus and Staphylococcus aureus, respectively. After evisceration, both patients received treatment, had a good outcome, and were discharged to continue their hemodialysis program. Metastatic bacterial endophthalmitis is a rare complication of dialysis catheter-related bacteremia. When suspected, urgent ophthalmologic evaluation and treatment are needed to reduce the risk of losing vision in the affected eye.

Diferença de tempo de positividade: método útil no diagnóstico de infecção de corrente sanguínea relacionada com cateter?

INTRODUÇÃO: As infecções de corrente sanguínea relacionadas com cateter (ICSRCs) apresentam impacto significativo na morbidade e na mortalidade de pacientes internados, além de elevar custos hospitalares. A utilização de equipamentos automatizados no processamento de hemoculturas gerou uma alternativa para diagnóstico de ICSRC por meio da análise da diferença de tempo de positividade (DTP) entre hemoculturas pareadas (coletadas simultaneamente) de sangue periférico e sangue de cateter. Um diagnóstico acurado e rápido dessas infecções pode otimizar as condutas clínicas e terapêuticas, poupando a retirada precoce dos cateteres. OBJETIVOS: Avaliar na rotina a DTP como ferramenta auxiliar no diagnóstico de ICSRC e determinar os principais microrganismos isolados. MÉTODOS: Foram avaliadas retrospectivamente hemoculturas coletadas no complexo do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC/FMUSP) de maio a agosto de 2008. Somente amostras que apresentaram DTP maior que 120 minutos foram consideradas possíveis ICSRCs pelo critério laboratorial. RESULTADOS: A seção processou 11.017 hemoculturas aeróbias durante o período de estudo; somente 5% foram coletadas de forma pareada. Destas, 148 (28%) foram positivas, sendo 9% com crescimento somente em sangue periférico, 41% somente em sangue de cateter e 50% em ambas as amostras com 88% de homologia de microrganismos identificados. A DTP apresentou valores acima de 120 minutos em 50% dos casos e os microrganismos mais isolados foram Staphylococcus aureus (22%), Candida spp. (18%), Klebsiella spp. (7%) e Enterobacter spp. (7%). CONCLUSÃO: A determinação da DTP como ferramenta auxiliar no diagnóstico de ICSRC é viável e fácil de ser executada em laboratórios de rotina com automação, porém o processo de coleta das amostras pareadas deve ser rigidamente padronizado.

Comparative Genome Analysis of Trichophyton rubrum and Related Dermatophytes Reveals Candidate Genes Involved in Infection

The major cause of athlete's foot is Trichophyton rubrum, a dermatophyte or fungal pathogen of human skin. To facilitate molecular analyses of the dermatophytes, we sequenced T. rubrum and four related species, Trichophyton tonsurans, Trichophyton equinum, Microsporum canis, and Microsporum gypseum. These species differ in host range, mating, and disease progression. The dermatophyte genomes are highly colinear yet contain gene family expansions not found in other human-associated fungi. Dermatophyte genomes are enriched for gene families containing the LysM domain, which binds chitin and potentially related carbohydrates. These LysM domains differ in sequence from those in other species in regions of the peptide that could affect substrate binding. The dermatophytes also encode novel sets of fungus-specific kinases with unknown specificity, including nonfunctional pseudokinases, which may inhibit phosphorylation by competing for kinase sites within substrates, acting as allosteric effectors, or acting as scaffolds for signaling. The dermatophytes are also enriched for a large number of enzymes that synthesize secondary metabolites, including dermatophyte-specific genes that could synthesize novel compounds. Finally, dermatophytes are enriched in several classes of proteases that are necessary for fungal growth and nutrient acquisition on keratinized tissues. Despite differences in mating ability, genes involved in mating and meiosis are conserved across species, suggesting the possibility of cryptic mating in species where it has not been previously detected. These genome analyses identify gene families that are important to our understanding of how dermatophytes cause chronic infections, how they interact with epithelial cells, and how they respond to the host immune response. IMPORTANCE Athlete's foot, jock itch, ringworm, and nail infections are common fungal infections, all caused by fungi known as dermatophytes (fungi that infect skin). This report presents the genome sequences of Trichophyton rubrum, the most frequent cause of athlete's foot, as well as four other common dermatophytes. Dermatophyte genomes are enriched for four gene classes that may contribute to the ability of these fungi to cause disease. These include (i) proteases secreted to degrade skin; (ii) kinases, including pseudokinases, that are involved in signaling necessary for adapting to skin; (iii) secondary metabolites, compounds that act as toxins or signals in the interactions between fungus and host; and (iv) a class of proteins (LysM) that appear to bind and mask cell wall components and carbohydrates, thus avoiding the host's immune response to the fungi. These genome sequences provide a strong foundation for future work in understanding how dermatophytes cause disease.

HEV infection in swine from Eastern Brazilian Amazon: Evidence of co-infection by different subtypes

Hepatitis E virus (HEV) is a fecal-orally transmitted member of the genus Hepevirus that causes acute hepatitis in humans and is widely distributed throughout the world. Pigs have been reported as the main source of genotypes 3 and 4 infection to humans in non-endemic areas. To investigate HEV infection in pigs from different regions of Para state (Eastern Brazilian Amazon), we performed serological and molecular analyses of serum, fecal and liver samples from 151 adult pigs slaughtered between April and October 2010 in slaughterhouses in the metropolitan region of Belem, Para. Among the animals tested, 8.6% (13/151) were positive for anti-HEV IgG but not for anti-HEV IgM. HEV RNA was detected in 4.8% (22/453) of the samples analyzed and 9.9% (15/151) of the animals had at least one positive sample. Phylogenetic analysis showed that all sequences belonged to genotype 3 that were related to human isolates from other non-endemic regions, suggesting that the isolates had zoonotic potential. Subtypes 3c and 3f were simultaneously detected in some pigs, suggesting co-infection by more than one strain and/or the presence of a recombinant virus. These results constitute the first molecular and serologic evidence of swine HEV circulation in the Eastern Brazilian Amazon. (C) 2012 Elsevier Ltd. All rights reserved.

Age-Related Expansion of Tim-3 Expressing T Cells in Vertically HIV-1 Infected Children

As perinatally HIV-1-infected children grow into adolescents and young adults, they are increasingly burdened with the long-term consequences of chronic HIV-1 infection, with long-term morbidity due to inadequate immunity. In progressive HIV-1 infection in horizontally infected adults, inflammation, T cell activation, and perturbed T cell differentiation lead to an "immune exhaustion'', with decline in T cell effector functions. T effector cells develop an increased expression of CD57 and loss of CD28, with an increase in co-inhibitory receptors such as PD-1 and Tim-3. Very little is known about HIV-1 induced T cell dysfunction in vertical infection. In two perinatally antiretroviral drug treated HIV-1-infected groups with median ages of 11.2 yr and 18.5 yr, matched for viral load, we found no difference in the proportion of senescent CD28(-)CD57(+)CD8(+) T cells between the groups. However, the frequency of Tim-3(+)CD8(+) and Tim-3(+)CD4(+) exhausted T cells, but not PD-1(+) T cells, was significantly increased in the adolescents with longer duration of infection compared to the children with shorter duration of HIV-1 infection. PD-1(+)CD8(+) T cells were directly associated with T cell immune activation in children. The frequency of Tim-3(+)CD8(+) T cells positively correlated with HIV-1 plasma viral load in the adolescents but not in the children. These data suggest that Tim-3 upregulation was driven by both HIV-1 viral replication and increased age, whereas PD-1 expression is associated with immune activation. These findings also suggest that the Tim-3 immune exhaustion phenotype rather than PD-1 or senescent cells plays an important role in age-related T cell dysfunction in perinatal HIV-1 infection. Targeting Tim-3 may serve as a novel therapeutic approach to improve immune control of virus replication and mitigate age related T cell exhaustion.

Dissecting Phaseolus vulgaris Innate Immune System against Colletotrichum lindemuthianum Infection

Background: The genus Colletotrichum is one of the most economically important plant pathogens, causing anthracnose on a wide range of crops including common beans (Phaseolus vulgaris L.). Crop yield can be dramatically decreased depending on the plant cultivar used and the environmental conditions. This study aimed to identify potential genetic components of the bean immune system to provide environmentally friendly control measures against this fungus. Methodology and Principal Findings: As the common bean is not amenable to reverse genetics to explore functionality and its genome is not fully curated, we used putative Arabidopsis orthologs of bean expressed sequence tag (EST) to perform bioinformatic analysis and experimental validation of gene expression to identify common bean genes regulated during the incompatible interaction with C. lindemuthianum. Similar to model pathosystems, Gene Ontology (GO) analysis indicated that hormone biosynthesis and signaling in common beans seem to be modulated by fungus infection. For instance, cytokinin and ethylene responses were up-regulated and jasmonic acid, gibberellin, and abscisic acid responses were down-regulated, indicating that these hormones may play a central role in this pathosystem. Importantly, we have identified putative bean gene orthologs of Arabidopsis genes involved in the plant immune system. Based on experimental validation of gene expression, we propose that hypersensitive reaction as part of effector-triggered immunity may operate, at least in part, by down-regulating genes, such as FLS2-like and MKK5-like, putative orthologs of the Arabidopsis genes involved in pathogen perception and downstream signaling. Conclusions/Significance: We have identified specific bean genes and uncovered metabolic processes and pathways that may be involved in the immune response against pathogens. Our transcriptome database is a rich resource for mining novel defense-related genes, which enabled us to develop a model of the molecular components of the bean innate immune system regulated upon pathogen attack.

Plasma levels of complement proteins from the alternative pathway in patients with age-related macular degeneration are independent of Complement Factor H Tyr(402)His polymorphism

Purpose: To investigate the influence of the Factor H (CFH) Tyr(402)His polymorphism on the plasma levels of the alternative pathway proteins CFH, C3, Factor B (FB), Factor D (FD), and Factor I (FI) and the inflammatory marker C-reactive protein (CRP) in 119 patients with age-related macular degeneration (AMD) and 152 unrelated control individuals. Methods: Patients with AMD and the control group were separated according to CFH polymorphism, age, and gender. Plasma complement proteins and CRP concentrations were determined with enzyme-linked immunosorbent assay, immunodiffusion, or nephelometry. Results: Significant differences in the concentrations of FD and FI were observed between the patients with AMD and the control individuals. We observed significantly reduced FD plasma levels in patients with AMD. We also identified a significant decrease in CFH plasma levels in female patients with AMD in relation to female controls. Plasma FI levels were significantly increased in patients with AMD compared to the control group. Regarding gender, a significant increase in FI plasma levels was observed in male patients. Finally, we found no significant correlation between the CFH Tyr(402)His polymorphism and the CFH, C3, FB, FD, FI, and CRP plasma levels. Conclusions: Patients with AMD present altered levels of FD and FI in a manner independent of this CFH polymorphism, and gender apparently contributes to the plasma levels of these two proteins in patients with AMD and control individuals.

Invasive aspergillosis: a severe infection in juvenile systemic lupus erythematosus patients

Infections are an important cause of morbidity and mortality in juvenile systemic lupus erythematosus (JSLE). Among them, invasive aspergillosis (IA), which is usually related to immunosuppressed patients, has been rarely reported in JSLE. From 1983 to 2011, 5604 patients were followed at our institution and 283 (5%) met the American College of Rheumatology (ACR) classification criteria for SLE. Six (2.1%) of our JSLE patients had IA. One of them was previously reported and five will be described herein. Four of them were female. The median age at JSLE diagnosis was 12 years (8-16) and the median interval between diagnosis of JSLE and IA was 6 months (1-38). All had pulmonary involvement and three of them had systemic involvement. The median Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) was 19 (7-22). Diagnosis of IA was performed by isolation of Aspergillus spp., two in bronchoalveolar lavage culture and by way of autopsy in the others. All of them were treated with corticosteroids and/or immunosuppressive drugs at IA diagnosis (azathioprine and/or intravenous cyclophosphamide). They all required treatment in the pediatric intensive care unit with mechanical ventilation and antifungal therapy (fluconazole, amphotericin B, itraconazole and/or voriconazole); nonetheless, none of them survived. In conclusion, this was the first report that evaluated the prevalence of IA in a large population of JSLE patients from a tertiary pediatric hospital, and clearly showed the severity of the outcome, especially in patients with active disease and treated with immunosuppressive agents. This study reinforces the importance of early diagnosis and treatment with certain antifungals, especially in critically ill patients. Lupus (2012) 21, 1011-1016.

Vectorial capacity, basic reproduction number, force of infection and all that: formal notation to complete and adjust their classical concepts and equations

A dimensional analysis of the classical equations related to the dynamics of vector-borne infections is presented. It is provided a formal notation to complete the expressions for the Ross' threshold theorem, the Macdonald's basic reproduction "rate" and sporozoite "rate", Garret-Jones' vectorial capacity and Dietz-Molineaux-Thomas' force of infection. The analysis was intended to provide a formal notation that complete the classical equations proposed by these authors.

Salivary immunity in elderly individuals presented with Candida-related denture stomatitis

Objectives: Elderly individuals with Candida-related denture stomatitis (DS) present with a reduced defence against Candida albicans. This study evaluated levels of antimicrobial mediators in the elderly DS saliva and salivary neutrophils' activation characteristics compared with elderly and young without DS. Methods: Salivary peroxidases (SPO) and elastase activities (ELA), nitric oxide (NO), transforming growth factor beta (TGF-beta), IL-6 and CCL3 production were determined in saliva from elderly with or without DS, and young control individuals. TLR4, CXCR1, CD11b, CD16 and CD32 expression on salivary neutrophils were evaluated. Correlations between number and apoptosis rate of salivary neutrophils, enzymatic activities and cytokine levels were determined. Results: Elderly DS individuals exhibited the lowest SPO and ELA activities. Also, the activity of both enzymes was low in elderly without DS. Although both elderly groups showed higher salivary NO and TGF-beta levels compared to young control groups, elderly DS presented the highest salivary NO, TGF-beta, IL-6 and CCL3 levels. Decreased percentages of salivary TLR4(+) and CD16(+) neutrophils were detected in both elderly groups. Although these damages could influence the establishment and persistence of DS, the highest levels of salivary IL-6 and CCL3 in elderly DS could be preventing more serious complications.

Activation pattern of neutrophils from blood of elderly individuals with -related denture stomatitis

We have identified impaired neutrophils in elderly individuals which could be involved with -related denture stomatitis (DS), an oral infection predominantly caused by , affecting especially elderly individuals using dental prosthesis. However, specific mechanisms performed by neutrophil contributing to the susceptibility of the elderly to DS are not fully understood. This study evaluated activation features of blood neutrophils from elderly and young individuals with DS. Blood neutrophils cultured with . from elderly subjects secreted decreased levels of CXCL8. However, . challenged-neutrophils from DS patients produced high IL-4 and IL-10, and low GM-CSF levels, regardless of age. Additional elastase activity of neutrophils from both elderly groups was detected after incubation with . , but only neutrophils from elderly DS demonstrated high myeloperoxidase activity. Therefore, DS patients have affected neutrophils, and the advance of age intensifies these damages. In sumamry, individuals with -related denture stomatitis presented variation in the neutrophil phenotype and activation. Such alterations were more intense in neutrophils from infected elderly individuals.

Potential costs of bacterial infection on storage protein gene expression and reproduction in queenless Apis mellifera worker bees on distinct dietary regimes

Insects are able to combat infection by initiating an efficient immune response that involves synthesizing antimicrobial peptides and a range of other defense molecules. These responses may be costly to the organism, resulting in it exploiting endogenous resources to maintain homeostasis or support defense to the detriment of other physiological needs. We used queenless worker bees on distinct dietary regimes that may alter hemolymph protein storage and ovary activation to investigate the physiological costs of infection with Serratia marcescens. The expression of the genes encoding the storage proteins vitellogenin and hexamerin 70a, the vitellogenin receptor, and vasa (which has a putative role in reproduction), was impaired in the infected bees. This impairment was mainly evident in the bees fed beebread, which caused significantly higher expression of these genes than did royal jelly or syrup, and this was confirmed at the vitellogenin and hexamerin 70a protein levels. Beebread was also the only diet that promoted ovary activation in the queenless bees, but this activation was significantly impaired by the infection. The expression of the genes encoding the storage proteins apolipophorins-I and -III and the lipophorin receptor was not altered by infection regardless the diet provided to the bees. Similarly, the storage of apolipophorin-I in the hemolymph was only slightly impaired by the infection, independently of the supplied diet. Taken together these results indicate that, infection demands a physiological cost from the transcription of specific protein storage-related genes and from the reproductive capacity. (C) 2012 Elsevier Ltd. All rights reserved.

Bacillus cereus infection outbreak in captive psittacines

This study reports an uncommon epizootic outbreak of Bacillus cereus that caused the sudden death of 12 psittacines belonging to the species Anodorhynchus hyacinthinus (1 individual), Diopsittaca nobilis (1 individual), Ara severe (1 individual) and Ara ararauna (9 individuals) in a Brazilian zoo. Post-mortem examination of the animals reveled extensive areas of lung hemorrhage, hepatic congestion, hemorrhagic enteritis and cardiac congestion. Histopathological examination of the organs showed the presence of multiple foci of vegetative cells of Gram-positive bacilli associated with discrete and moderate mononuclear inflammatory cell infiltrate. Seventeen B. cereus strains isolated from blood and sterile organs of nine A. ararauna were analyzed in order to investigate the genetic diversity (assessed by Rep-PCR) and toxigenic profiles (presence of hblA, hblC and hblD; nheA, nheB and nheC as well as cytK, ces and entFM genes) of such strains. Amplification of genomic DNA by Rep-PCR of B. cereus strains generated two closely related profiles (Rep-PCR types A and B) with three bands of difference. All strains were classified as belonging to the toxigenic profile I which contained HBL and NHE gene complexes, entFM and cytK genes. Altogether, microbiological and histopathological findings and the evidence provided by the success of the antibiotic prophylaxis, corroborate that B. cereus was the causative agent of the infection that killed the birds. (C) 2012 Elsevier B.V. All rights reserved.

Murine Dendritic Cells Transcriptional Modulation upon Paracoccidioides brasiliensis Infection

Limited information is available regarding the modulation of genes involved in the innate host response to Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis. Therefore, we sought to characterize, for the first time, the transcriptional profile of murine bone marrow-derived dendritic cells (DCs) at an early stage following their initial interaction with P. brasiliensis. DCs connect innate and adaptive immunity by recognizing invading pathogens and determining the type of effector T-cell that mediates an immune response. Gene expression profiles were analyzed using microarray and validated using real-time RT-PCR and protein secretion studies. A total of 299 genes were differentially expressed, many of which are involved in immunity, signal transduction, transcription and apoptosis. Genes encoding the cytokines IL-12 and TNF-alpha, along with the chemokines CCL22, CCL27 and CXCL10, were up-regulated, suggesting that P. brasiliensis induces a potent proinflammatory response in DCs. In contrast, pattern recognition receptor (PRR)-encoding genes, particularly those related to Toll-like receptors, were down-regulated or unchanged. This result prompted us to evaluate the expression profiles of dectin-1 and mannose receptor, two other important fungal PRRs that were not included in the microarray target cDNA sequences. Unlike the mannose receptor, the dectin-1 receptor gene was significantly induced, suggesting that this beta-glucan receptor participates in the recognition of P. brasiliensis. We also used a receptor inhibition assay to evaluate the roles of these receptors in coordinating the expression of several immune-related genes in DCs upon fungal exposure. Altogether, our results provide an initial characterization of early host responses to P. brasiliensis and a basis for better understanding the infectious process of this important neglected pathogen.

Epidemiological, parasitological and molecular aspects of Giardia duodenalis infection in children attending public daycare centers in southeastern Brazil

The purpose of this study was to determine the prevalence, associated risk factors and genotype of Giardia duodenalis infection in children attending public daycare centers in the city of Araguari, state of Minas Gerais, Brazil. Fecal samples were collected from 245 children aged 0-5 years, and questionnaires were asked about sociodemographic and hygiene-related characteristics. At the daycare centers where children tested positive, fecal samples were collected from the staff handling food, and from family members and domestic animals. Positive samples were analyzed at the dehydrogenase glutamate (gdh) locus to determine the genotype. The prevalence of G. duodenalis was 51.8%, and drinking unfiltered and unboiled water (OR 2.12, CI 1.26-3.69, p<0.001) and washing hands only with water (OR 2.14, Cl 1.19-4.04, p<0.001) were related risk factors. No association was found between test-positive children anti their family members, domestic animals and food handlers. An analysis of the sequences of 30 samples revealed that they all belonged to genotype B. (C) 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.