Coagulase-negative staphylococci isolates from blood cultures of newborns in a tertiary hospital in southern Brazil

Abstract Neonatal sepsis continues to be a major cause of morbidity and mortality worldwide. Coagulase-negative staphylococci (CoNS), commonly found on the skin, being the main agents isolated. The aim of this study was to evaluate CoNS isolated from blood cultures of newborn (NB) infants. The study took place between 2014 and 2016/2017 in a tertiary hospital in southern Brazil. Using the VITEK 2 system (bioMérieux, Marcy l'Etoile, France), the microorganisms were identified and had their sensitivity profiles determined. The minimum inhibitory concentrations of linezolid, tigecycline, and vancomycin were also determined. The clinical parameters and mortality rates of NBs were evaluated. From January to December 2014, 176 CoNS isolates were obtained from 131 patients and from June 2016 to July 2017, 120 CoNS isolates were obtained from 79 patients. Staphylococcus epidermidis was most prevalent in both periods. Resistance rates increased between 2014 and 2016/2017, especially against ciprofloxacin (52.27% and 73.11%, p = 0.0004), erythromycin (51.40% and 68.07%, p = 0.0054), gentamicin (50.59% and 67.23%, p = 0.0052), and penicillin (71.3% and 99.17%, p = 0.0001), respectively. With 100% susceptibility to linezolid, tigecycline, and vancomycin in both periods and methodologies tested. In 2014, 53.44% of the NBs received antibiotic therapy, and of these, 77.14% used a catheter; in 2016/2017, these were 78.48% and 95.16%, respectively. Regarding laboratory tests, a hemogram was ineffective, since patients with sepsis presented normal reference values. In 2014 and 2016/17, 15.71% and 17.74% of the NBs died, respectively. S. epidermidis was the predominant microorganism, related to catheter use in most cases. The resistance rates have increased over time, demonstrating the importance of adopting control and prevention measures in this hospital. CoNS are responsible for a significant neonatal sepsis mortality rate in infants.

Método fenotípico automatizado versus método manual na identificação de microorganismos isolados de hemoculturas: desfechos clínicos e microbiológicos / Automated phenotypic method versus manual method in the identification of microorganisms isolated from blood cultures: clinical and microbiological outcomes

INTRODUÇÃO: A automação laboratorial é cada vez mais utilizada em microbiologia, no entanto, poucos estudos avaliam desfechos clínicos em comparação aos métodos tradicionais. No Brasil, nenhum estudo com esse objetivo foi detectado. OBJETIVO: Analisar os impactos clínicos e microbiológicos após implantação de método fenotípico automatizado em um serviço de microbiologia. MÉTODOS: Realizamos estudo observacional e retrospectivo no laboratório de microbiologia referente a exame de hemocultura de pacientes da Unidade de Terapia Intensiva (UTI). Os dados foram coletados de pacientes internados entre janeiro/2014 a dezembro/2015. Analisou-se o tempo de internação, número de terapias empíricas, óbitos e dados relacionados ao isolamento microbiológico. A amostra foi obtida por conveniência. Para a comparação entre os desfechos foram empregados os testes t de Student e Qui-quadrado de Pearson. O programa empregado foi o Stata release, versão 11, sendo considerados significativos valores de p<0,05. RESULTADOS: Foram avaliados 472 pacientes. Não houve redução na prescrição empírica de antimicrobianos (54,7% vs 45,3%; p=0,33), tempo de internação na UTI (14,5 dias vs 15,8 dias p=0,78) e na taxa de óbitos (54,4% vs 45,6%; p=0,36). Similarmente, o perfil de agentes isolados em ambos os métodos não parece ser discrepante, no entanto, houve um aumento de 44,7% no número de isolados microbianos (76 vs 110) com melhor caracterização dos mesmos. CONCLUSÃO: A automação do laboratório de microbiologia não impactou no tempo de internação, mortalidade na UTI e no número de terapias empíricas. No entanto, a identificação e o isolamento de microrganismos melhoraram.

INTRODUCTION: Automation is increasingly used in microbiology laboratory, however, few studies assessed clinical outcomes compared to traditional methods. In Brazil, no studies with this objective were detected. OBJECTIVE: To analyze the clinical and microbiological impacts after implantation of an automated phenotypic method in a microbiology service. METHODS: Observational and retrospective study carried out on the microbiology laboratory involving blood culture test from intensive care unit (ICU) patients. Data were collected from hospitalized patients between January 2014 and December 2015. The length of hospitalization, number of empirical therapies, deaths and information related to microbiological isolation were analyzed. The sample was obtained by convenience. Pearson's Chisquare and Student's t-tests were used to compare outcomes. The program used was the Stata release, version 11, being considered significant values of p<0.05. RESULTS: A total of 472 patients were evaluated. There was no reduction in the empirical prescription of antimicrobials (54.7% vs 45.3%; p=0.33), ICU stay (14.5 days vs 15.8 days; p=0.78) and mortality (54.4% vs 45.6%; p=0.36). Similarly, profile of isolated agents in both methods did not appear to be discrepant, however, there was an increase of 44.7% in the number of microbial isolates (76 vs 110) and a better characterization of them. CONCLUSION: The microbiology laboratory automation did not modify the length of stay, ICU mortality and the number of empirical therapies. However, identification and isolation of microorganisms was improved.

Diagnostic value of pediatric blood culture bottles for acute postoperative endophthalmitis

OBJECTIVE: To report our experience using conventional culture methods (CM) and pediatric blood culture bottles (PBCBs) for vitreous sample culture of acute postoperative endophthalmitis. METHODS: A retrospective study was conducted at the Department of Ophthalmology, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, BR, from January 2010 to December 2015, and it included 54 patients with clinically suspected acute postoperative endophthalmitis. Vitreous samples were obtained by vitreous tap or vitrectomy. Samples from January 2010 to December 2011 were cultivated in CM, whereas samples from January 2012 to December 2015 were inoculated in PBCBs. The measured outcome was the yield of positive cultures. RESULTS: Twenty cases were included in the CM group, and 34 cases were included in the PBCB group. The yield of positive cultures in PBCBs (64.7%) was significantly higher than that in conventional CM (35%, p=0.034). Staphylococcus epidermidis and Streptococcus viridans were the two most commonly found agents. CONCLUSION: PBCBs can be used successfully in clinically suspected endophthalmitis. The method showed a higher yield of positive cultures than the conventional method. This technique appears to have several advantages over the traditional method: it saves time, as only one medium needs to be inoculated; transportation to a laboratory is easier than in the traditional method, and there is no need to maintain a supply of fresh agar media. The use of PBCBs may be recommended as the primary method for microbiological diagnosis and is especially suitable for office settings and remote clinics.