Ricardo de Souza Kuchenbecker

Secular Trends in Nosocomial Bloodstream Infections: Antibiotic-Resistant Bacteria Increase the Total Burden of Infection

BACKGROUND It is unknown whether rising incidence rates of nosocomial bloodstream infections (BSIs) caused by antibiotic-resistant bacteria (ARB) replace antibiotic-susceptible bacteria (ASB), leaving the total BSI rate unaffected. METHODS We investigated temporal trends in annual incidence densities (events per 100 000 patient-days) of nosocomial BSIs caused by methicillin-resistant Staphylococcus aureus (MRSA), ARB other than MRSA, and ASB in 7 ARB-endemic and 7 ARB-nonendemic hospitals between 1998 and 2007. RESULTS 33 130 nosocomial BSIs (14% caused by ARB) yielded 36 679 microorganisms. From 1998 to 2007, the MRSA incidence density increased from 0.2 to 0.7 (annual increase, 22%) in ARB-nonendemic hospitals, and from 3.1 to 11.7 (annual increase, 10%) in ARB-endemic hospitals (P = .2), increasing the incidence density difference between ARB-endemic and ARB-nonendemic hospitals from 2.9 to 11.0. The non-MRSA ARB incidence density increased from 2.8 to 4.1 (annual increase, 5%) in ARB-nonendemic hospitals, and from 1.5 to 17.4 (annual increase, 22%) in ARB-endemic hospitals (P < .001), changing the incidence density difference from -1.3 to 13.3. Trends in ASB incidence densities were similar in both groups (P = .7). With annual increases of 3.8% and 5.4% of all nosocomial BSIs in ARB-nonendemic and ARB-endemic hospitals, respectively (P < .001), the overall incidence density difference of 3.8 increased to 24.4. CONCLUSIONS Increased nosocomial BSI rates due to ARB occur in addition to infections caused by ASB, increasing the total burden of disease. Hospitals with high ARB infection rates in 2005 had an excess burden of BSI of 20.6 per 100 000 patient-days in a 10-year period, mainly caused by infections with ARB.

Impact of hospital-wide infection rate, invasive procedures use and antimicrobial consumption on bacterial resistance inside an intensive care unit

We performed a 30-month ecological study to determine the impact of hospital-wide antibiotic consumption, invasive procedure use and hospital-acquired infections (HAIs) on antibiotic resistance in an intensive care unit (ICU). Microbiological isolates from ICU patients with established diagnosis of hospital infection were monitored throughout the study. Overall hospital consumption per 100 patient-days of piperacillin-tazobactam, fluoroquinolones and cephalosporins increased from 1.9 to 2.3 defined daily doses (DDD) (P<0.01), from 4.7 to 10.3 DDD (P<0.01) and from 12.1 to 16.4 DDD (P<0.01), respectively. Bacterial multiresistance in ICU was identified in 31.3% (N=466) of isolates, with increasing resistance demonstrated for meropenem-resistant Klebsiella spp. (P=0.01) and meropenem-resistant Acinetobacter spp. (P=0.02). There was a positive correlation between multiresistance rate and DDD of cephalosporins (P<0.01) and fluoroquinolones (P=0.03). The rate of ceftazidime-resistant Klebsiella spp. correlated with DDD of fluoroquinolones and cephalosporins; the rate of ceftazidime-resistant Pseudomonas spp. correlated with consumption of cephalosporins, and rate of meticillin-resistant Staphylococcus aureus (MRSA) correlated with fluoroquinolone use. During the studied period, 36.9% (P<0.001) and 34.5% (P<0.01) of the changing multiresistance rate in ICU was associated with use of invasive procedures and overall HAI rate, respectively. Multiresistance rates in ICU are influenced by the variation in overall HAI rate, hospital-wide invasive procedures and antibiotic consumption outside the ICU.

Infection-related microcephaly after the 2015 and 2016 Zika virus outbreaks in Brazil: a surveillance-based analysis

BACKGROUND On Nov 11, 2015, the Brazilian Ministry of Health declared a Public Health Emergency of National Concern in response to an increased number of microcephaly cases, possibly related to previous Zika virus outbreaks. We describe the course of the dual epidemics of the Zika virus infection during pregnancy and microcephaly in Brazil up to Nov 12, 2016, the first anniversary of this declaration. METHODS We used secondary data for Zika virus and microcephaly cases obtained through the Brazilian Ministry of Healths surveillance systems from Jan 1, 2015, to Nov 12, 2016. We deemed possible Zika virus infections during pregnancy as all suspected cases of Zika virus disease and all initially suspected, but later discarded, cases of dengue and chikungunya fever. We defined confirmed infection-related microcephaly in liveborn infants as the presence of a head circumference of at least 2 SDs below the mean for their age and sex, accompanied by diagnostic imaging consistent with an infectious cause, or laboratory, clinical, or epidemiological results positive for Zika virus or STORCH (infectious agents known to cause congenital infection, mainly syphilis, toxoplasmosis, cytomegalovirus, and herpes simplex virus). We excluded cases of congenital anomalies or death without microcephaly. We analyse the spatial clustering of these diseases in Brazil to obtain the kernel density estimation. FINDINGS Two distinct waves of possible Zika virus infection extended across all Brazilian regions in 2015 and 2016. 1 673 272 notified cases were reported, of which 41 473 (2·5%) were in pregnant women. During this period, 1950 cases of infection-related microcephaly were confirmed. Most cases (1373 [70·4%]) occurred in the northeast region after the first wave of Zika virus infection, with peak monthly occurrence estimated at 49·9 cases per 10 000 livebirths. After a major, well documented second wave of Zika virus infection in all regions of Brazil from September, 2015, to September, 2016, occurrence of microcephaly was much lower than that following the first wave of Zika virus infection, reaching epidemic levels in all but the south of Brazil, with estimated monthly peaks varying from 3·2 cases to 15 cases per 10 000 livebirths. INTERPRETATION The distribution of infection-related microcephaly after Zika virus outbreaks has varied across time and Brazilian regions. Reasons for these apparent differences remain to be elucidated. FUNDING None.

Desafios e perspectivas futuras dos hospitais universitários no Brasil

A mudanca das instituicoes hospitalares verificada internacionalmente envolve particularmente os Hospitais Universitarios (HU). O presente artigo objetiva promover uma reflexao acerca de desafios dos HU brasileiros. O texto atem-se a analise daqueles hospitais vinculados as Instituicoes Federais de Ensino Superior. Ha substantiva heterogeneidade entre os HU, envolvendo desde os perfis assistenciais, porte e modelos de gestao. No Brasil, os HU sao agentes nucleares de duas politicas de Estado - educacao e saude. E no âmbito dos HU que se manifestam os tensionamentos inerentes a complexidade de articulacao de tais politicas. Os HU tem sido incitados a oferecer respostas a problemas que transcendem sua capacidade. Cabe fortalecer a sustentabilidade organizacional dos HU, incluindo a capacidade de implantacao de mecanismos de saneamento financeiro, de indicadores de avaliacao e gestao, a incorporacao das questoes afetas a qualidade dos servicos prestados, a transparencia e a responsabilidade social. Aos HU cabem melhorar as condicoes de saude da populacao. A efetivacao desses papeis e mais ampla do que conceber os HU somente como instituicoes prestadoras de servicos. O futuro e a afirmacao dos HU dependera da sua capacidade de contribuir para acoes integradoras nas politicas de Estado para a saude e educacao.

High endemic levels of multidrug-resistant Acinetobacter baumannii among hospitals in southern Brazil

BACKGROUND Most published data on multidrug-resistant Acinetobacter baumanii (MDR Ab) are derived from outbreaks. We report incidence trends on health care-acquired infections due to MDR Ab over a 12-month period in the city of Porto Alegre in southern Brazil. METHODS Clinical and epidemiologic data were obtained from the local health care information system of the municipal health department. Polymerase chain reaction was used to detect the presence of the genes bla(OXA-23-like), bla(OXA-24-like), bla(OXA-51), and bla(OXA-58), and repetitive sequence-based polymerase chain reaction and pulsed-field gel electrophoresis were performed for molecular typing. RESULTS The highest rate of infection (9.0/1,000 inpatient-days) was identified in a trauma hospital. The gene bla(OXA-23-like) was identified in 99.0% of MDR Ab isolates. Eight main clonal groups were identified by molecular typing, and 3 of these were found in all hospitals. CONCLUSION The presence of 3 clones in all hospitals demonstrates the ability of MDR Ab to spread among hospitals. Moreover, the occurrence of one particular clone (clone 4) throughout the study period suggests its increased ability to cause outbreaks and to remain in the environment. The monitoring of epidemic strains by molecular methods is of paramount importance to prevent or reduce the spread of MDR Ab.

Prevalence and acquisition of MRSA amongst patients admitted to a tertiary-care hospital in brazil

BackgroundThere are few studies in Brazil that address baseline prevalence of MRSA colonization and associated risk factors at hospital admission, or the incidence of nosocomial colonization. We report a prospective study in a tertiary-care, university-affiliated hospital to implement a new MRSA control policy at the institution.MethodsA cohort of randomly selected patients admitted to emergency and clinical wards at our hospital was followed until discharge. Nasal swabs were taken for identification of MRSA-colonized patients and detection of SCCmecA in positive cultures, at admission and weekly thereafter. Multivariate analysis using a log-binomial analysis was used to identify risk factors for colonization.ResultsAfter screening 297 adult patients and 176 pediatric patients, the prevalence of MRSA at admission was 6.1% (95%CI, 3.6% to 9.4%), in the adult population and 2.3% (95%CI, 0.6% to 5.7%), for children. From multivariate analysis, the risk factors associated with colonization in adults were: age above 60 years (P = 0.019) and hospitalization in the previous year (P = 0.022). Incidence analysis was performed in 276 MRSA-negative patients (175 adults and 101 children). Acquisition rate was 5.5/1,000 patient-days for adults (95%CI, 3.4 to 8.5/1,000 patients-days), and 1.1/1,000 patient-days for children (95%CI, 0.1 to 4.0/1,000 patients-days).ConclusionsThe identification of MRSA carriers is a step towards establishing a control policy for MRSA, and helps to identify measures needed to reduce colonization pressure and to decrease the high acquisition rate in hospitalized patients.

Evaluation of respiratory syncytial virus group A and B genotypes among nosocomial and community-acquired pediatric infections in southern Brazil

BackgroundRespiratory syncytial virus (RSV) is the main cause of lower respiratory tract illness in children worldwide. Molecular analyses show two distinct RSV groups (A and B) that comprise different genotypes. This variability contributes to the capacity of RSV to cause yearly outbreaks. These RSV genotypes circulate within the community and within hospital wards. RSV is currently the leading cause of nosocomial respiratory tract infections in pediatric populations. The aim of this study was to evaluate the G protein gene diversity of RSV amplicons.MethodsNasopharyngeal aspirate samples were collected from children with nosocomial or community-acquired infections. Sixty-three RSV samples (21 nosocomial and 42 community-acquired) were evaluated and classified as RSV-A or RSV-B by real-time PCR. Sequencing of the second variable region of the G protein gene was performed to establish RSV phylogenetics.ResultsWe observed co-circulation of RSV-A and RSV-B, with RSV-A as the predominant group. All nosocomial and community-acquired RSV-A samples were from the same phylogenetic group, comprising the NA1 genotype, and all RSV-B samples (nosocomial and community-acquired) were of the BA4 genotype. Therefore, in both RSV groups (nosocomial and community-acquired), the isolates belonged to only one genotype in circulation.ConclusionsThis is the first study to describe circulation of the NA1 RSV genotype in Brazil. Furthermore, this study showed that the BA4 genotype remains in circulation. Deciphering worldwide RSV genetic variability will aid vaccine design and development.

Optimization of one-step duplex real-time RT-PCR for detection of influenza and respiratory syncytial virus in nasopharyngeal aspirates.

Viruses are major contributors to acute respiratory infection-related morbidity and mortality worldwide. The influenza (IF) viruses and human respiratory syncytial virus (RSV) play a particularly important role in the etiology of acute respiratory infections. This study sought to standardize a one-step duplex real-time RT-PCR technique to optimize diagnosis of IFA/IFB and RSVA/RSVB infection. Viral RNA was extracted with the commercially available QIAamp Mini Kit according to manufacturer instructions. RT-PCR was performed with primers to the matrix protein gene of IFA, the hemagglutinin gene of IFB and the N gene of RSVA and RSVB. The limits of detection were 1 copy/μL for IFA, 10 copies/μL for IFB, 5 copies/μL for RSVA, and 250 copies/μL for RSVB. The specificity of RT-PCR was determined by comparison against a panel of several respiratory pathogens. RT-PCR and indirect immunofluorescence (IIF) were compared in a sample of 250 nasopharyngeal aspirates (NPAs) collected during the year 2010. RT-PCR was more sensitive than IIF and able to detect viral co-infections. In summary, RT-PCR optimized for IFA/IFB and RSVA/RSVB is sensitive and specific for these viral agents and is therefore useful for assessment of the etiology of respiratory infections, whether for clinical or epidemiological purposes.

Changes in hand hygiene compliance after a multimodal intervention and seasonality variation

BACKGROUND Hand hygiene is the most important measure to reduce health care-related infections and colonization with multiresistant micro-organisms. We sought to determine the rate and seasonality of handwashing compliance in a university-affiliated hospital. METHODS In January 2006 (baseline period), handwashing observation was first made in an intensive care unit. From March to May 2006, there was an intervention period; and, from June 2006 to August 2009, we followed hand hygiene compliance. Seasonality curves for handwashing compliance were made during follow-up period. RESULTS During baseline period, a total of 166 observations was made. During follow-up, 17,664 opportunities for hand hygiene were observed. Compliance improved from 30.0% to a mean of 56.7% after the intervention (P < .001). The highest mean rate of compliance was 77.9% for nurses, compared with 52.6% for technicians (P < .001) and 44.6% for physicians (P < .001). Compliance was lower during summer days (first trimester of the year) and increased after March and April and slowly decreased through the end of the year. CONCLUSION One of the reasons for the lower handwashing compliance in the first 3 months of the year is that, in Brazil, this is the summer vacation time; and, because of that, the staffs workload and the number of less well-trained personnel are higher. We emphasize the importance of continuously monitoring hand hygiene to determine the seasonal aspects of compliance.

Text mining approach to predict hospital admissions using early medical records from the emergency department

OBJECTIVE Emergency department (ED) overcrowding is a serious issue for hospitals. Early information on short-term inward bed demand from patients receiving care at the ED may reduce the overcrowding problem, and optimize the use of hospital resources. In this study, we use text mining methods to process data from early ED patient records using the SOAP framework, and predict future hospitalizations and discharges. DESIGN We try different approaches for pre-processing of text records and to predict hospitalization. Sets-of-words are obtained via binary representation, term frequency, and term frequency-inverse document frequency. Unigrams, bigrams and trigrams are tested for feature formation. Feature selection is based on χ2 and F-score metrics. In the prediction module, eight text mining methods are tested: Decision Tree, Random Forest, Extremely Randomized Tree, AdaBoost, Logistic Regression, Multinomial Naïve Bayes, Support Vector Machine (Kernel linear) and Nu-Support Vector Machine (Kernel linear). MEASUREMENTS Prediction performance is evaluated by F1-scores. Precision and Recall values are also informed for all text mining methods tested. RESULTS Nu-Support Vector Machine was the text mining method with the best overall performance. Its average F1-score in predicting hospitalization was 77.70%, with a standard deviation (SD) of 0.66%. CONCLUSIONS The method could be used to manage daily routines in EDs such as capacity planning and resource allocation. Text mining could provide valuable information and facilitate decision-making by inward bed management teams.