Resistência à sulfadoxina-pirimetamina em Maputo, Moçambique: presença de mutações nos genes dhfr e dhps do Plasmodium falciparum

Foram analisadas a freqüência e distribuição de mutações nos genes dihidrofolato redutase e dihidropteroato sintetase do Plasmodium falciparum, usando a metodologia de reação em cadeia da polimerase e polimorfismos de hidrólise por enzimas de restrição, em amostras de sangue infectado proveniente de crianças moçambicanas, residentes em Maputo. A análise foi feita antes e 7 dias após o tratamento com sulfadoxina-pirimetamina (S/P). Os resultados mostraram a ocorrência de mutações pontuais nos genes estudados e a presença de combinações de três alelos em dhfr (51Ile, 59Arg e 108Asn) e do quintúplo mutante (dhfr 51Ile, 59Arg, 108Asn e dhps 437Gly, 540Glu), ambas situações associadas à falha terapêutica no sétimo dia após tratamento com S/P. Esses achados mostram a importância de se estudar a resistência à S/P em Moçambique, e como os marcadores moleculares de resistência aos antimaláricos podem fornecer dados importantes para a política nacional de controlo da malária.

Trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital: a 4-year study

INTRODUCTION: In the past two decades members of the genus Enterococcus have emerged as important nosocomial pathogens worldwide. This study prospectively analyzed the distribution of species and trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital from 2006-2009. METHODS: Enterococcal species were identified by conventional biochemical tests. The antimicrobial susceptibility profile was performed by disk diffusion in accordance with the Clinical and Laboratory Standards Institute (CLSI). A screening test for vancomycin was also performed. Minimal inhibitory concentration (MIC) for vancomycin was determined using the broth dilution method. Molecular assays were used to confirm speciation and genotype of vancomycin-resistant enterococci (VRE). RESULTS: A total of 324 non-repetitive enterococcal isolates were recovered, of which 87% were E. faecalis and 10.8% E. faecium. The incidence of E. faecium per 1,000 admissions increased significantly (p < 0.001) from 0.3 in 2006 to 2.3 in 2009. The VRE rate also increased over time from 2.5% to 15.5% (p < 0.001). All VRE expressed high-level resistance to vancomycin (MIC >256µg/ mL) and harbored vanA genes. The majority (89.5%) of VRE belonged to E. faecium species, which were characteristically resistant to ampicillin and quinolones. Overall, ampicillin resistance rate increased significantly from 2.5% to 21.4% from 2006-2009. Resistance rates for gentamicin, chloramphenicol, tetracycline, and erythromycin significantly decreased over time, although they remained high. Quinolones resistance rates were high and did not change significantly over time. CONCLUSIONS: The data obtained show a significant increasing trend in the incidence of E. faecium resistant to ampicillin and vancomycin.

Nosocomial infection and characterization of extended-spectrum β-lactamases-producing Enterobacteriaceae in Northeast Brazil

INTRODUCTION: Extended spectrum β-lactamases (ESBLs) are enzymes that degrade β-lactam antibiotics and have been reported to be an important cause of nosocomial infection in worldwide. METHODS: During 2009, 659 enterobacteria strains were isolated from different clinical specimens and tested for ESBL production. The disk approximation test, combined disk method and addition of clavulanic acid were used for phenotypic detection of the ESBL-producing strains and PCR for detection of the blaTEM and blaCTX-M genes. RESULTS: Among the isolates, 125 were ESBL producers. The blaCTX-M and blaTEM genes were detected in 90.4% and 75% of the strains, respectively. Most strains were isolated from urine. Klebsiella pneumoniae was the most prevalent organism. Microorganisms presented high resistance to the antibiotics. CONCLUSIONS: These results support the need for extending ESBL detection methods to different pathogens of the Enterobacteriaceae family because these methods are only currently standardized by the CLSI for Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Proteus mirabilis. Carbapenems were the antibiotic class of choice for the treatment of infections caused by ESBL-producing Enterobacteriaceae.

Multidrug resistance genes, including blaKPC and blaCTX-M-2, among Klebsiella pneumoniae isolated in Recife, Brazil

INTRODUCTION: The prevalence of cephalosporins and carbapenem-resistant Klebsiella pneumoniae strains is rising in Brazil, with potential serious consequences in terms of patients' outcomes and general care. METHODS: This study characterized 24 clinical isolates of K. pneumoniae from two hospitals in Recife, Brazil, through the antimicrobial susceptibility profile, analyses of β-lactamase genes (blaTEM, blaSHV,blaCTX-MblaKPC, blaVIM, blaIMP, and blaSPM), plasmidial profile and ERIC-PCR (Enterobacterial repetitive intergenic consensus-polymerase chain reaction). RESULTS: ERIC-PCR and plasmidial analysis grouped the isolates in 17 and 19 patterns, respectively. Six isolates from one hospital presented the same pattern by ERIC-PCR, indicating clonal dissemination. All isolates presented blaSHV, 62.5% presented blaCTX-M-2, 29% blaTEM, and 41.7% blaKPC. Metallo-β-lactamase genes blaand blawere not detected. Eleven isolates were identified carrying at least 3 β-lactamase studied genes, and 2 isolates carried blaSHVblaTEM, blaCTX-M-2 and blaKPC simultaneously. CONCLUSIONS: The accumulation of resistance genes in some strains, observed in this study, imposes limitations in the therapeutic options available for the treatment of infections caused by K. pneumoniae in Recife, Brazil. These results should alert the Brazilian medical authorities to establish rigorous methods for more efficiently control the dissemination of antimicrobial resistance genes in the hospital environment.

Prevalence of enterotoxin-encoding genes and antimicrobial resistance in coagulase-negative and coagulase-positive Staphylococcus isolates from black pudding

INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS) and coagulasepositive (CoPS) isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa) and enterotoxin (se) genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82) were CoNS and 24.4% (20/82) were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8%) and Staphylococcus carnosus (15.9%) were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82) of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6%) and seb (27.5%). CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.

In vitro antifungal activities of leaf extracts of Lippia alba (Verbenaceae) against clinically important yeast species

Introduction There are few studies reporting the antifungal activities of Lippia alba extracts. Methods A broth microdilution assay was used to evaluate the antifungal effects of Lippia alba extracts against seven yeast species of Candida and Cryptococcus. The butanol fraction was investigated by gas chromatography-mass spectrometry. Results The butanol fraction showed the highest activity against Candida glabrata. The fraction also acted synergistically with itraconazole and fluconazole against C. glabrata. The dominant compounds in the butanol fraction were 2,2,5-trimethyl-3,4-hexanedione, 3,5-dimethyl-4-octanone and hexadecane. Conclusions The butanol fraction may be a good candidate in the search for new drugs from natural products with antifungal activity.

Genes that encodes NAGT, MIF1 and MIF2 are not virulence factors for kala-azar caused by Leishmania infantum

IntroductionKala-azar is a disease resulting from infection by Leishmania donovani and Leishmania infantum. Most patients with the disease exhibit prolonged fever, wasting, anemia and hepatosplenomegaly without complications. However, some patients develop severe disease with hemorrhagic manifestations, bacterial infections, jaundice, and edema dyspnea, among other symptoms, followed by death. Among the parasite molecules that might influence the disease severity are the macrophage migration inhibitory factor-like proteins (MIF1 and MIF2) and N-acetylglucosamine-1-phosphotransferase (NAGT), which act in the first step of protein N-glycosylation. This study aimed to determine whether MIF1, MIF2 and NAGT are virulence factors for severe kala-azar.MethodsTo determine the parasite genotype in kala-azar patients from Northeastern Brazil, we sequenced the NAGT genes of L. infantum from 68 patients as well as the MIF1 and MIF2 genes from 76 different subjects with diverse clinical manifestations. After polymerase chain reaction (PCR), the fragments were sequenced, followed by polymorphism identification.ResultsThe nucleotide sequencing of the 144 amplicons revealed the absence of genetic variability of the NAGT, MIF1 and MIF2 genes between the isolates. The conservation of these genes suggests that the clinical variability of kala-azar does not depend upon these genes. Additionally, this conservation suggests that these genes may be critical for parasite survival.ConclusionsNAGT, MIF1 and MIF2 do not alter the severity of kala-azar. NAGT, MIF1 and MIF2 are highly conserved among different isolates of identical species and exhibit potential for use in phylogenetic inferences or molecular diagnosis.

Influence of a subinhibitory concentration of vancomycin on the in vitro expression of virulence-related genes in the vancomycin-resistant Enterococcus faecalis

ABSTRACTINTRODUCTION:Exposure to subinhibitory concentrations (SICs) of antimicrobials may alter the bacterial transcriptome.METHODS: Here, we evaluated the expression of nine virulence-related genes in vancomycin-resistant enterococci (VRE) urinary tract infection isolates grown at SICs of vancomycin.RESULTS:A Subinhibitory concentrations of vancomycin interferes with gene modulation, but does not affect the phenotype of a VRE strain in vitro .CONCLUSIONS:Subinhibitory concentrations of vancomycin may regulate the expression of virulence factors in vivo or contribute to the selection of vancomycin-resistant strains.

Antimicrobial resistance profiles and oxacillinase genes in carbapenem-resistant Acinetobacter baumannii isolated from hospitalized patients in Santa Catarina, Brazil

Abstract: INTRODUCTION: Carbapenems are the therapy of choice for treating severe infections caused by the Acinetobacter calcoaceticus-Acinetobacter baumannii complex. We aimed to assess the prevalence and antimicrobial susceptibility profiles of producers of distinct oxacillinases among nosocomial isolates of the A. calcoaceticus-A. baumannii complex in a 249-bed general hospital located in Joinville, Southern Brazil. METHODS: Of the 139 A. baumannii clinical isolates with reduced susceptibility to carbapenems between 2010 and 2013, 118 isolates from varying anatomical sites and hospital sectors were selected for genotypic analysis. Five families of genes encoding oxacillinases, namely blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, and blaOXA-143-like, wereinvestigated by multiplex polymerase chain reaction (PCR). RESULTS: Most (87.3%) isolates simultaneously carried the blaOXA-23-likeand blaOXA-51-likegenes, whereas three (2.5%) isolates harbored only blaOXA-51-likeones. The circulation of carbapenem-resistant isolates increased during the study period: from none in 2010, to 22 in 2011, 64 in 2012, and 53 in 2013. CONCLUSIONS: Isolates carrying the blaOXA-23-likeand blaOXA-51-likegenes were widely distributed in the hospital investigated. Because of the worsening scenario, the implementation of preventive measures and effective barriers is needed.

Hydronephrosis in Schinzel-Giedion syndrome: an important clue for the diagnosis

Schinzel-Giedion syndrome is a rare autosomal recessive disorder characterized by coarse facies, midface retraction, hypertrichosis, multiple skeletal anomalies, and cardiac and renal malformations. Craniofacial abnormalities of this syndrome sometimes resemble a storage or metabolic disease. The pathogenesis of the disease remains unknown. The objective of this report was to emphasize the importance of congenital bilateral hydronephrosis for the diagnosis of Schinzel-Giedion syndrome. We describe the first Brazilian case of a newborn with typical facies, generalized hypertrichosis, cardiac and skeletal anomalies, and bilateral hydronephrosis detected during pregnancy and confirmed later by abdominal ultrasonography. Chromosomal constitution was normal. Of the 35 cases already reported in the literature, 31 presented hydronephrosis, which is considered an important clue in diagnosis. If Schinzel-Giedion syndrome were indexed as a cause of congenital hydronephrosis, its identification would be greatly facilitated, since the majority of the other findings in Schinzel-Giedion syndrome are nonspecific and common to many genetic syndromes.

Estudos de associação entre transtorno obsessivo-compulsivo e genes candidatos: uma revisão

OBJETIVO: Nos últimos anos, o papel dos genes dos sistemas serotoninérgicos e dopaminérgicos tem sido sistematicamente investigado em pacientes com transtorno obsessivo-compulsivo (TOC), uma vez que esses neurotransmissores apresentam uma provável implicação na fisiopatologia do TOC. Este artigo objetiva revisar os principais resultados de estudos de associação entre genes candidatos e TOC. MÉTODOS: Revisão da literatura na base de dados Medline até agosto de 2006, utilizando as palavras-chave obsessive-compulsive disorder (OCD) e/ou gene(s), polymorphism(s), genetics. RESULTADOS: Inúmeros estudos têm apresentado resultados negativos ao compararem pacientes com TOC e controles, entretanto resultados positivos têm sido observados em pacientes com TOC com características clínicas particulares (sexo, idade de início, dimensão ou gravidade dos sintomas obsessivos ou compulsivos e presença de tiques). CONCLUSÃO: Para garantir a continuidade do avanço de estudos genéticos, é necessária a identificação de subgrupos homogêneos de pacientes com TOC. Diante desses grupos, será possível delinear endofenótipos confiáveis que permitam explorar de forma mais específica a contribuição dos diferentes genes na patogênese da doença.

Catecholaminergic polymorphic ventricular tachycardia. An important diagnosis in children with syncope and normal heart

Syncope in children is primarily related to vagal hyperreactivity, but ventricular tachycardia (VT) way rarely be seen. Catecholaminergic polymorphic VT is a rare entity that can occur in children without heart disease and with a normal QT interval, which may cause syncope and sudden cardiac death. In this report, we describe the clinical features, treatment, and clinical follow-up of three children with syncope associated with physical effort or emotion and cathecolaminergic polymorphic VT. Symptoms were controlled with beta-blockers, but one patient died suddenly in the fourth year of follow-up. Despite the rare occurrence, catecholaminergic polymorphic VT is an important cause of syncope and sudden death in children with no identified heart disease and normal QT interval.

Stress During ACLS Courses: Is it Important for Learning Skills?

OBJECTIVE: To determine the influence of stress on teaching medical emergencies in an Advanced Cardiac Life Support (ACLS) course and to verify this influence on learning, and the efficiency of emergency care training. METHODS: Seventeen physicians signed up for an ACLS course. Their pulses were taken and blood pressure (BP) verified on the first day, before the beginning of the course, and on the second day, during the theoretical and practical test (TPT). Variations in pulse rates and BP were compared with students' test grades. Then, students answered a questionnaire of variables (QV) about the amount of sleep they had during the course, the quantity of study material and the time spent studying for the course, and a stress scale graphic. RESULTS: Seven students had a pulse variation less than 10% between the 2 periods and 10 had a 10% or more variation. Grades on TPT were, respectively, 91.4±2.4 and 87.3±5.2 (p<0.05). Six students had a BP variation less than 20 mmHg, and in 11 it varied more than 21 mmHg. Grades on the TPT were 92.3±3.3 and 86.2± 8.1, respectively (p<0.05). The QV dates did not significantly influence grades. CONCLUSION: Stress, as an isolated variable, had a negative influence on the learning process and on the efficiency of emergency training in this situation.