Healthcare-associated infections in high-risk neonates: Temporal trends in a national surveillance system.

BACKGROUND: Increased survival of preterm neonates who require hospitalization at the Neonatal Intensive Care Unit has led to an increase in infections. This study aims to describe the temporal trend, risk factors, and outcome of healthcare-associated infections in a NICU of a high complexity hospital, with emphasis on the differences of incidence between bacterial and fungal infections. METHODS: The study was carried out from January 2013 to December 2016, with daily follow-up of the newborns by the National Healthcare Safety Network. RESULTS: The study included 881 newborns, of whom 214 had a bacterial infection, 19 had fungi infection, and 12 bacterial and fungal infections associated. The hospital infection rate was 12/1000 patient-days. SNAPPE>24, days of hospitalization and PICC days were independent risk factors for the development of fungal and bacterial infection, respectively, with statistical significance for bacterial and fungal infections. The mortality rate was 2.6 times higher in those who had fungal infection than in those who had a bacterial infection. The occurrence of invasive infections was higher in the years 2015 and 2016 and Gram-negative bacteria and yeasts were more frequent, impacting morbidity and mortality. CONCLUSIONS: The use of invasive devices is a risk factor for the occurrence of HAI caused by bacteria and fungi. The frequency of deaths was higher in the group of neonates with fungal infection. These results point to the importance of constant epidemiological surveillance and measures of effective control of infections in NICU.

Characterization of Candida species isolated from the hands of the healthcare workers in the neonatal intensive care unit.

Colonization of health professional hands by potentially pathogenic microorganisms capable to expressing virulence factors, such as Candida spp., is worrisome because of the high contact between patients and professionals. The study aims to evaluate, in vitro, the following virulence factors: hemolytic activity, DNAse expression, biofilm formation, and susceptibility for antifungal agents of Candida species isolated from health professionals hands of a neonatal intensive care unit (NICU). The study includes 50 isolates of Candida spp.: 19 C. parapsilosis sensu stricto, three C. metapsilosis, one C. orthopsilosis, seven C. albicans, six C. famata, five C. lusitaniae, three C. krusei, two C. kefyr, two C. tropicalis, one C. glabrata, and one C. guilliermondii. The hemolytic activity and DNAse were investigated using blood agar and DNAse agar, respectively. Biofilm production was evaluated through XTT sodium salt reduction ability, and the susceptibility of the isolates to antifungals through the microdilution methodology. Forty-nine isolates presented at least one of the three virulence factors investigated. C. albicans showed more intense hemolytic activity. DNAse production was statistically significant between the C. parapsilosis complex and C. albicans, as well as between the C. parapsilosis complex and C. krusei, even as between C. famata and C. albicans, and between C. famata and C. krusei. Forty-three isolates produced biofilm. Seventy-eight percent of the isolates were sensitive to the three antifungals tested. This study demonstrated that Candida isolated from healthcare professionals' hands has virulence.

Geraniol and linalool anticandidal activity, genotoxic potential and embryotoxic effect on zebrafish.

AIM: Geraniol and linalool are major constituents of the essential oils of medicinal plants. MATERIALS & METHODS: Antifungal activity of geraniol and linalool were evaluated against five Candida species. The genotoxicity of these compounds was evaluated by the cytokinesis-block micronucleus test, and the embryotoxic assays use zebrafish model. RESULTS: Geraniol and linalool inhibited Candida growth, but geraniol was more effective. The geraniol at concentration of 800 µg/ml and the linalool at concentration of 125 µg/ml significantly increased chromosome damage. Geraniol was more toxic to zebrafish embryo than linalool: LC50 values were 31.3 and 193.3 µg/ml, respectively. CONCLUSION: Geraniol and linalool have anticandidal activity, but they also exert genotoxic and embryotoxic effects at the highest tested concentrations.

Evaluation of the disk diffusion method for testing fluconazole susceptibility of Cryptococcus laurentii

Cryptococcus laurentii é um patógeno humano raro, ubíquo na natureza. O objetivo deste estudo foi avaliar a aplicação do método de difusão do disco para determinar a sensibilidade ao fluconazol de isolados de C. laurentii e determinar a concentração fungicida mínima (CFM) do fluconazol. Foi determinada a sensibilidade ao fluconazol pelos métodos de difusão do disco e microdiluição em caldo de 11 isolados de C. laurentii, de acordo com CLSI (Clinical and Laboratory StandardsInstitute), e a CFM pelo método de microdiluição em caldo. O método de difusão do disco mostrou quatro isolados sensíveis, três sensíveis dose-dependentes e quatro resistentes, enquanto que pelo método de microdiluição, 10 isolados foram sensíveis e um sensível dose-dependente. A concordância entre os dois métodos foi de 36,4por cento. Um isolado apresentou CFM de 8 mi g/mL e dois de 64 mi g/mL. Embora o número de isolados estudados seja pequeno, os resultados sugeremque o método de difusão do disco não deve ser usado na determinação da sensibilidade in vitro dos isolados de C. laurentii ao fluconazol, e apesar de ser uma droga fungistática, o fluconazol pode apresentar atividade fungicida in vitro para alguns isolados do complexo C. laurentii.

Cryptococcus neoformans var. grubii - Pathogenicity of environmental isolates correlated to virulence factors, susceptibility to fluconazole and molecular profile

The pathogenicity of Cryptococcus neoformans is heterogeneous and is associated with the expression of virulence factors. This study aimed to correlate the pathogenicity of C. neoformans var. grubii in BALB/c mice with in vitro virulence factors, fluconazole minimal inhibitory concentrations (MICs) and molecular profiles, before and after animal passage. Ten environmental isolates and one ATCC strain of C. neoformans var. grubii mating type α were evaluated. Most isolates (91 percent) killed 50 percent or more of the infected animals by day 24 postinfection and were recovered from the lungs and brains of surviving animals on days 7 and 14 postinfection. The burden of yeast in the lungs was more variable than that in the brain. The differences in the expression of virulence factors (growth at 37ºC, presence and size of the capsule and production of melanin, urease, proteinase and phospholipase) by most isolates pre and postpassage in animals were not statistically significant. The fluconazole MICs in postpassaged lines differed by a one-dilution from the MIC of the corresponding prepassaged line for six isolates. Using molecular typing [polymerase chain reaction-fingerprinting with (GACA)4 and M13], eight isolates were identified as VNI and three as VNII. We concluded that different isolates with the same molecular and phenotypic profiles, including isolates that are markedly hypervirulent, span a wide range of virulence and there were no changes in virulence factors in the postpassaged lines when compared with the corresponding nonpassaged lines.

Cryptococcus neoformans var. grubii - Pathogenicity of environmental isolates correlated to virulence factors, susceptibility to fluconazole and molecular profile.

The pathogenicity of Cryptococcus neoformans is heterogeneous and is associated with the expression of virulence factors. This study aimed to correlate the pathogenicity of C. neoformans var. grubii in BALB/c mice with in vitro virulence factors, fluconazole minimal inhibitory concentrations (MICs) and molecular profiles, before and after animal passage. Ten environmental isolates and one ATCC strain of C. neoformans var. grubii mating type α were evaluated. Most isolates (91%) killed 50% or more of the infected animals by day 24 postinfection and were recovered from the lungs and brains of surviving animals on days 7 and 14 postinfection. The burden of yeast in the lungs was more variable than that in the brain. The differences in the expression of virulence factors (growth at 37ºC, presence and size of the capsule and production of melanin, urease, proteinase and phospholipase) by most isolates pre and postpassage in animals were not statistically significant. The fluconazole MICs in postpassaged lines differed by a one-dilution from the MIC of the corresponding prepassaged line for six isolates. Using molecular typing [polymerase chain reaction-fingerprinting with (GACA)4 and M13], eight isolates were identified as VNI and three as VNII. We concluded that different isolates with the same molecular and phenotypic profiles, including isolates that are markedly hypervirulent, span a wide range of virulence and there were no changes in virulence factors in the postpassaged lines when compared with the corresponding nonpassaged lines.

Variability in UVB tolerances of melanized and nonmelanized cells of Cryptococcus neoformans and C. laurentii.

Solar radiation is one of the major factors responsible for the control of fungus populations in the environment. Inactivation by UVA and UVB radiation is especially important for the control of fungi that disperse infective units through the air, including fungi such as Cryptococcus spp. that infect their vertebrate hosts by inhalation. Cryptococcus neoformans produces melanin in the presence of certain exogenous substrates such as l-3,4 dihydroxyphenylalanine and melanization may protect the fungus against biotic and abiotic environmental factors. In the present study, we investigated the effect of exposure to an UVB irradiance of 1000 mW m(-2) (biologically effective weighted irradiance) on the survival of melanized and nonmelanized cells of four strains of C. neoformans and four strains of C. laurentii. The relative survival (survival of cells exposed to radiation in relation to cells not exposed) of cells grown 2, 4, 6 or 8 days on medium with or without L-dopa was determined after exposure to UVB doses of 1.8 and 3.6 kJ m(-2). Both the irradiance spectrum and the intensities of those doses are environmentally realistic, and, in fact, occur routinely during summer months in temperate regions. Differences in tolerance to UVB radiation were observed between the C. neoformans and C. laurentii strains. The C. neoformans strains were more susceptible to UVB radiation than the C. laurentii strains. In C. neoformans, differences in tolerance to radiation were observed during development of both melanized and nonmelanized cells. For most treatments (strain, time of growth and UVB dose), there were virtually no differences in tolerances between melanized and nonmelanized cells, but when differences occurred they were smaller than those previously observed with UVC. In tests with two strains of C. laurentii, there was no difference in tolerance to UVB radiation between melanized and nonmelanized cells during 8 days of culture; and in tests with four strains for less culture time (4 days) there were no significant differences in tolerance between melanized and nonmelanized cells of any strain of this species.

The isolation and characterization of virulence factors of Cryptococcus spp. from saprophytic sources in the city of Ribeirão Preto, São Paulo, Brazil.

Yeasts of the Cryptococcus genus are distributed in nature associated to animal and vegetal organic residues. Occasionally, species other than C. neoformans may be responsible for infectious diseases in human and animals. This study aims to determine the occurrence of Cryptococcus species in the atmosphere and bird droppings in the city of Ribeirão Preto, São Paulo, Brazil, and to evaluate three virulence factors: capsule formation, growth at 37 degrees C and melanin production. We analyzed 86 environmental samples (54 droppings and 32 air). Of the 41 strains isolated, 15 were C. neoformans var. neoformans (12 droppings and 3 air), 15 C. albidus (12 droppings and 3 air), 9 C. laurentii (7 droppings and 2 air) and 2 C. uniguttulatus (from droppings). Capsules were produced by 93.3% of C. neoformans var. neoformans, 66.7% of C. albidus, 88.9% of C. laurentii and 50% (1/2) of C. uniguttulatus. All strains of C. neoformans, 20% of C. albidus and 44.4% of C. laurentii were able to grow at 37 degrees C. The melanin production on DOPA agar was verified in C. neoformans (93.3%), C. albidus (26.7%) and C. laurentii (66.7%). We concluded that different Cryptococcus species coexist in the same ecological niche and they are able to produce virulence factors.

Pesquisa de cistos de protozoários, larvas e ovos de helmintos em chupetas / A study on protozoan cysts, helminth eggs larvae in pacifiers

Objetivo: Devido à alta prevalência das enteroparasitoses entre crianças no Brasil e do possível envolvimento de objetos na transmissäo dessas doenças, foi desenvolvido um estudo para pesquisar a presença de cistos de protozoários, larvas e ovos de helmintos em chupetas. Métodos: No período de março a dezembro de 1993, foram examinadas 86 chupetas de crianças na faixa etária de zero a sete anos, residentes no bairro Vila Promessa, município de Alfenas, MG. A pesquisa de cistos, larvas e ovos foi realizada através do exame microscópico do sedimento obtido da centrifugaçäo do líquido resultante da lavagem das chupetas. Os resultados obtidos foram avaliados empregando-se a análise percentual. Paralelamente aos exames, foram realizadas entrevistas com os responsáveis pela criança...