Carlos Levy - Academia.edu (original) (raw)

Papers by Carlos Levy

Medical Microbiology and Immunology

International journal of antimicrobial agents, Jan 23, 2018

Journal of clinical microbiology, 2018

A DNA microarray platform, based on the nucleotide sequences of the internal transcribed spacer r... more A DNA microarray platform, based on the nucleotide sequences of the internal transcribed spacer regions (ITS1 and ITS2) of the rRNA gene, was developed to identify 32 fungal pathogens at the species level. The probe sequences were spotted onto polycarbonate slides with a mini-microarray printer, and after the hybridization, the results were visible with the naked eye. The performance of the microarray platform was evaluated against the commercial automated systems (Vitek 2 and BD Phoenix systems) and DNA sequencing (gold standard). A total of 461 blood culture bottles were tested: 127 positive for fungi, 302 positive for bacteria, and 32 that were negative. Once the microorganisms were identified by automated systems, fungal DNA was extracted directly from the blood culture bottles. The DNA products were tested using the microarray platform, and DNA sequencing was performed. The results of the microarray and DNA sequencing were concordant in 96.7% of cases, and the results from the ...

Surgical technology international, 2018

Surgical site infection (SSI) is a common complication that is associated with delayed recovery, ... more Surgical site infection (SSI) is a common complication that is associated with delayed recovery, prolonged length of hospital stay, exorbitant cost, and mortality. The present prospective longitudinal study aimed to evaluate the relationships between the microbial load of trocars used in laparoscopic gynecological surgery, microbiota in surgical sites, and SSI. The final sample consisted of 24 patients, including 68 swab samples and 48 trocars. Microorganisms were recovered in 100.0% of the swabs collected from the umbilicus and vaginal fornix and in 58.3% (14/24) of the swabs collected from skin at the left McBurney's point. Most of the samples collected from trocars (87.5%) did not exhibit bacterial growth, suggesting proper disinfection. In addition, antisepsis was effective for decolonization of the skin to create an aseptic surgical field.

Pathogens and disease, Jan 28, 2018

Nontuberculous mycobacteria (NTM) have been well established as an opportunistic pathogenic bacte... more Nontuberculous mycobacteria (NTM) have been well established as an opportunistic pathogenic bacterial group for cystic fibrosis (CF) patients, with a prevalence ranging from 3 to 23% worldwide. A myriad of factors can bias the prevalence rate in different CF centers, especially misdiagnosis as systematic screening for NTM are still lacking in a number of centers. Here, we evaluated the presence and clinical outcomes of NTM isolation in microbiological respiratory cultures from CF patients attending a Brazilian reference center after setting up a systematic diagnostic protocol. Of 117 patients with respiratory samples cultured for NTM research, we found seven patients (6%) with at least one positive result for NTM [four males (57.1%), Median Age = 21 years (9 - 58)]. These cases are reported one-by-one. Median FEV1 was 40%, all patients showed signs of lung deterioration, with a median number of pulmonary exacerbations of three per patient/year. However, the impact of NTM isolation r...

Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology], Jan 4, 2017

Identification of nonfermenting Gram-negative bacteria (NFGNB) of cystic fibrosis patients is har... more Identification of nonfermenting Gram-negative bacteria (NFGNB) of cystic fibrosis patients is hard and misidentification could affect clinical outcome. This study aimed to propose a scheme using polymerase chain reaction to identify NFGNB. This scheme leads to reliable identification within 3 days in an economically viable manner when compared to other methods.

Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society, Jan 11, 2017

The mechanisms leading to low effectiveness of the humoral immune response against P. aeruginosa ... more The mechanisms leading to low effectiveness of the humoral immune response against P. aeruginosa in cystic fibrosis (CF) are poorly understood. The aim of the present study was to assess the avidity maturation of specific antipseudomonal IgG before and during the development of chronic lung infection in a cohort of Danish CF patients. Avidity maturation was assessed against a pooled P. aeruginosa antigen (St-Ag) and against P. aeruginosa alginate in 10 CF patients who developed chronic lung infection and 10 patients who developed intermittent lung colonization, using an ELISA technique with the thiocyanate elution method. Avidity was quantitatively determined by calculating the avidity Constant (Kav). IgG avidity to St-Ag significantly increased at the onset (Median Kav=2.47) and one year after the onset of chronic infection (Median Kav=3.27), but did not significantly changed in patients who developed intermittent colonization. IgG avidity against alginate did not significantly cha...

Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society, Jan 12, 2017

P. aeruginosa chronic lung infection is the major cause of morbidity and mortality in patients wi... more P. aeruginosa chronic lung infection is the major cause of morbidity and mortality in patients with cystic fibrosis (CF), and is characterized by a biofilm mode of growth, increased levels of specific IgG antibodies and immune complex formation. However, despite being designed to combat this infection, such elevated humoral response is not associated with clinical improvement, pointing to a lack of anti-pseudomonas effectiveness. The mode of action of specific antibodies, as well as their structural features, and even the background involving B-cell production, stimulation and differentiation into antibody-producing cells in the CF airways are poorly understood. Thus, the aim of this review is to discuss studies that have addressed the intrinsic features of the humoral immune response and provide new insights regarding its insufficiency in the CF context.

Medical microbiology and immunology, Jan 30, 2017

The Burkholderia cepacia complex (BCC) can cause a severe decline in lung function in cystic fibr... more The Burkholderia cepacia complex (BCC) can cause a severe decline in lung function in cystic fibrosis (CF). Our objective was to determine the BCC prevalence and to evaluate its clinical impact on CF. Clinical and laboratory variables were determined for CF patients with BCC (Group-A = 50 patients) and without BCC (Group-B = 134 patients). The microorganisms were identified by biochemical tests, the Vitek2(®)Compact test, recA-PCR and recA-nested-PCR with species-specific primers and DNA sequencing. The patients were evaluated by the Shwachman-Kulczycki score (SKCS), Bhalla score (BS), spirometry and body mass index (BMI). The BCC prevalence was 22.5%. The most common species were Burkholderia multivorans (30%), Burkholderia cepacia (24%), Burkholderia cenocepacia IIIA (10%), B. cenocepacia IIIB (2%) and Burkholderia vietnamiensis (2%). There was difference between the groups in nutritional status (p = 0.02) and general activity (p = 0.026). There was difference in total BS points (...

Journal of Global Antimicrobial Resistance

The aim of this study was to determine the impact of two resolutions to restrict antibiotic use (... more The aim of this study was to determine the impact of two resolutions to restrict antibiotic use (RDCs no. 44/2010 and 20/2011) in the Campinas metropolitan area (Sao Paulo, Brazil) on antibiotic consumption, resistance rates, and trends in Escherichia coli-causing community-acquired urinary tract infection (UTI). The annual retail sale information of antibiotics from drugstores in the Campinas metropolitan area between 2008 and 2012 were obtained through the Intercontinental Medical Statistics Health of Brazil. The daily-defined dose (DDD)/1000 inhabitants/day was calculated from these data to measure consumption. To examine resistance rates, we performed an observational retrospective study in a Campinas teaching hospital, where urinary cultures from outpatients with a clinical suspicion of UTI between October 2009 and September 2015 were analyzed. We observed an increase in rates of antibiotic sales from 2008 to 2011 (cephalosporin: 216.8%, quinolones: 170.9%, aminopenicillins: 140.9%), followed by a decrease in sales in 2012 (cephalosporin: 19.4%, quinolones: 12.7%, aminopenicillins: 11.1%). Sale of nitrofurans, however, did not significantly change during this period. In the retrospective analysis, we observed a significant increasing trend of E. coli resistance for all antibiotic classes, except nitrofurans and folate pathway inhibitors. We found changes in antibiotic consumption, with an initial increase, followed by a decrease in sales after implementation of the resolutions. However, bacterial resistance does not appear to be affected by the RDCs.

Background: Cystic fibrosis is a disabling genetic disease with an increased prevalence in popula... more Background: Cystic fibrosis is a disabling genetic disease with an increased prevalence in populations with European heritage. Currently, the most used technique for collection of cystic fibrosis samples and diagnosis is provided through uncomfortable tests, with uncertain results, mostly based on chloride concentration in sweat. Since cystic fibrosis mutation induces many metabolic changes in patients, exploring these alterations might be an alternative to visualize potential biomarkers that could be used as interesting tools for further diagnostic upgrade, prioritizing simplicity, low cost and quickness. Methods: This contribution describes an accurate strategy to provide potential biomarkers related to cystic fibrosis, which may be understood as a potential tool for new diagnostic approaches and/or for monitoring disease evolution. Therefore, the present proposal consists of using skin imprints on silica plates as a way of sample collection, followed by direct-infusion high-resol...

Veterinary ophthalmology, Jan 15, 2017

Parasitic agents have been associated with keratitis, but a diagnosis of parasitic keratitis has ... more Parasitic agents have been associated with keratitis, but a diagnosis of parasitic keratitis has not been commonly made in domestic animals. The purpose of this study was to describe the clinical and histopathological findings in seven dogs with chronic keratitis caused by microfilariae diagnosed in Brazil. All dogs presented with superficial corneal opacities of varying degrees affecting the perilimbal and central regions of the cornea, with other opaque areas appearing as crystalline deposits and corneal vascularization. The lesions were bilateral and were associated with mild-to-moderate conjunctival hyperemia. There was no history of blepharospasm or pruritus, and no subjects presented with epithelial erosions. Corneal biopsy revealed free microfilariae in the corneal stroma, with varying degrees of inflammation and collagen fiber destruction. The microfilariae were also found in skin lesions by skin snip technique. No adult worms were found in these dogs, and no dogs were on he...

Pathogens and disease, Aug 22, 2017

We assessed the diagnostic ability of an ELISA test for measurement of specific secretory IgA (sI... more We assessed the diagnostic ability of an ELISA test for measurement of specific secretory IgA (sIgA) in saliva to identify Cystic Fibrosis (CF) patients with P. aeruginosa chronic lung infection and intermittent lung colonization. A total of 102 Brazilian CF patients and 53 healthy controls were included. Specific serum IgG response was used as a surrogate to distinguish CF patients according to their P. aeruginosa colonization/infection status. The rate of sIgA positivity was 87.1% in CF chronically infected patients (Median value = 181.5 U/mL), 48.7% in intermittently colonized patients (Median value = 45.8 U/mL) and 21.8% in free of infection patients (Median value = 22.1 U/mL). SIgA levels in saliva were significantly associated with serum P. aeruginosa IgG and microbiological culture results. The sensitivity, specificity, PPV and NPV for differentiation between presence and absence of chronic lung infection were 87%, 63%, 51% and 92%. Measurement of sIgA in saliva may be used f...

Memorias do Instituto Oswaldo Cruz, 2017

Enterocytozoon bieneusi are the most common microsporidia associated with different clinical mani... more Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E. bieneusi found in humans and animals in Brazil, there are no published studies of environmental samples examined by molecular methods. The purpose of this study was to verify the presence of E. bieneusi in raw sewage and treated effluent from a combined system by molecular methods. Raw sewage and treated effluent samples collected from a combined system were analysed for the presence of E. bieneusi using the internal transcriber spacer (ITS) region of E. bieneusi by nested polymerase chain react...

Lung, Aug 28, 2017

The aim of this study was to compare the qualitative and semi-quantitative detection of pathogens... more The aim of this study was to compare the qualitative and semi-quantitative detection of pathogens in the airway secretions of patients with cystic fibrosis (CF) and the sputum induction capacity before and after inhalation of 7% hypertonic saline solution (HSS). The study enrolled 64 patients with CF. Airway secretions were collected from all enrolled patients with CF before and after inhalation of 7% HSS, and the samples were screened for pathogens. Inhalation of 7% HSS increased the probability of producing sputum from 36 to 52% (p = 0.002) in children with CF. The effect was most in children under 11 years. Inhalation of 7% HSS improved qualitative pathogen identification (p = 0.008). Inhalation of 7% HSS increased the mucoid Pseudomonas aeruginosa (p = 0.002) and non-mucoid P. aeruginosa in the semi-quantitative analysis (p = 0.035). Four new pathogens (Aspergillus fumigatus, Achromobacter xylosoxidans, Ochrobactrum anthropi, and Elizabethkingia meningoseptica) were identified i...

Diagnostic Pathology, 2017

During production of the original article [1] the Methods section included an incorrect sentence.... more During production of the original article [1] the Methods section included an incorrect sentence. The following sentence "For the analysis of variables with numerical distribution, Fisher's exact test and one-way analysis of variance were used" should be corrected as "For the analysis of variables with numerical distribution, Student's t-test and one-way analysis of variance were used".

Diagnostic pathology, Jan 26, 2016

To assess the quality of sweat test (ST) based on the proportion of sweat sodium and sweat chlori... more To assess the quality of sweat test (ST) based on the proportion of sweat sodium and sweat chloride as diagnostic parameter of cystic fibrosis (CF). A retrospective study of 5,721 sweat samples and subsequent descriptive analysis were carried out. The test was considered "of good quality" (correct) when: (i) sweat chloride was lower than 60 mEq/L, and sweat sodium was higher than sweat chloride; (ii) sweat chloride was higher than 60 mEq/L, and sweat sodium was lower than sweat chloride. The study included 5,692/5,721 sweat samples of ST which had been requested due to clinical presentations compatible with CF and/or neonatal screenings with altered immunoreactive trypsinogen values. Considering the proportion of sweat sodium and sweat chloride as ST quality parameter, the test was performed correctly in 5,023/5,692 (88.2 %) sweat samples. The sweat chloride test results were grouped into four reference ranges for chloride (i) chloride < 30 mEq/L: 3,651/5,692 (64.1 %); ...

J Bras Patol, Sep 1, 2000

Base de dados : LILACS. Pesquisa : 275801 [Identificador único]. Referências encontradas : 1 [ref... more Base de dados : LILACS. Pesquisa : 275801 [Identificador único]. Referências encontradas : 1 [refinar]. Mostrando: 1 .. 1 no formato [Detalhado]. página 1 de 1, 1 / 1, LILACS, seleciona. para imprimir. Fotocópia. experimental, Documentos relacionados. Id: 275801. ...