Bacterial blood stream infections (BSI) are a common cause of mortality and morbidity globally. As the causative agents and the resulting treatment decisions vary, near-patient testing and ...surveillance tools are necessary to monitor bacterial causes and resistance to antimicrobial agents. The gold standard to identify BSIs is blood culture (BC), a methodology not widely available in resource-limited settings. The aim of the study was to map out a target product profile of a simplified BC system (SBCS) to inform product development efforts. To identify the desired characteristics of a SBCS, we enlisted a small group of specialists working in Africa and Asia. Questions were used to understand challenges and how these constraints inform system requirements. The specialists were infectious disease physicians, public health/clinical microbiologists, clinical researchers, and technology experts with different geographical backgrounds. All suggested that BC should ideally be available at the district hospital level. Many of the same operational challenges, such as limited availability of culture bottles, electricity and internet connectivity, profuse dust, the lack of ambient temperature control, and human capacity constraints were identified across the different regions. BCs, although the accepted gold standard for diagnosis of BSIs, are not widely available outside of reference/research centers in Africa and Asia. To extend the reach of this important tool, it is crucial to engage product developers and academic research partners to develop accessible alternatives.
Background False-positive blood cultures can lead to unnecessary risks and misuse of antibiotics; to reduce rates of false-positives, it would be useful to determine whether use of an antiseptic with ...a prolonged effect is required. Methods Clinical study of efficacy (blinded and randomized) to compare the rate of blood culture contamination when skin antisepsis was performed with 70% isopropyl alcohol or 2% chlorhexidine gluconate in 70% isopropyl alcohol in 2 hospitals. Patients aged 16 years or older with suspected bloodstream infection who were allocated in the emergency room, internal medicine ward, or intensive care unit were included. Results Five of 563 (0.9%) blood cultures from the isopropyl arm and 10 of 539 (1.9%) from the chlorhexidine arm were contaminated. No significant differences were observed among the rate of contamination (χ2 = 1.27; P = .3) or the relative risk of contamination (relative risk = 2.09; 95% confidence interval, 0.72-6.07; P = .2). Conclusions The rates of blood contamination were not different when isopropyl alcohol and chlorhexidine were compared. Isopropyl alcohol could be used for skin antisepsis before blood collection.
Coagulase-negative staphylococci (CNS) represent one of the most prevalent microorganisms in nosocomial infections worldwide, nevertheless little is known about their pathogenicity features. Thus, ...our aim was to characterize virulence aspects of CNS isolated from patients with bloodstream infections assisted in hospitals of Belo Horizonte, MG, Brazil. Strains were identified using bioMérieuxVitek® and for biofilm production evaluation, Congo Red Agar (CRA) and polystyrene plates were used. PCR was applied to detect icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr. For statistical analyses were used hierarchical cluster, chi-square test and correspondence. 59 strains were analyzed, being S. haemolyticus the most prevalent. On CRA, 96.5% were biofilm producer, whereas on polystyrene plate, 100% showed adhesion at different times evaluated. Regarding genotypic analyses, 15.2%, 38.9%, 8.4%, 49.1%, 76.2%, 23.7%, 1.6%, 30.5% and 38.9% were positive for icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr, respectively. Six clusters were formed and frequency distributions of agr, atlE, icaA, icaB, sea, sec, tsst-1 differed (P < 0.001). In conclusion, all strains were biofilm producer, with high prevalence of atlE, and had potential of toxin production, with high prevalence of sea. According to the group-analyses, icaB showed relationship with the strong adherence in samples.
•Coagulase-negative Staphylococci isolated from bloodstream infections were biofilm producer and atlE gene the most frequent.•This group of microorganisms showed high frequency of genes encoding for toxin production, especially for sea gene.•Statistical analyses showed a relationship between icaB locus and strong adherence in polystyrene plates.
Trypanosoma cruzi is the etiological agent of American trypanosomiasis (Chagas' disease), which affects 6–7 million people worldwide, mainly in Latin America. It presents great genetic and biological ...variability that plays an important role in the clinical and epidemiological features of the disease. Our working hypothesis is that the genetic diversity of T. cruzi has an important impact on detection of the parasite using diagnostic techniques. The present study evaluated the diagnostic performance of parasitological, molecular, and serological techniques for detecting 27 strains of T. cruzi that belonged to discrete typing units (DTUs) TcI (11 strains), TcII (four strains), and TcIV (12 strains) that were obtained from different hosts in the states of Amazonas and Paraná, Brazil. Blood samples were taken from experimentally infected mice and analyzed by fresh blood examination, hemoculture in Liver Infusion Tryptose (LIT) medium, polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA). Polymerase chain reaction presented the best detection of TcI, with 80.4% positivity. For all of the detection methods, the animals that were inoculated with TcII presented the highest positivity rates (94.1–100%). ELISA that was performed 7 months after inoculation presented a higher detection ability (95.4%) for TcIV. Intra-DTU comparisons showed that the reproducibility of the majority of the results that were obtained with the different methods was weak for TcI and good for TcII and TcIV. Our data indicate that the detection capability of different techniques varies with the DTUs of the parasites in mammalian blood. The implications of these findings with regard to the diagnosis of human T. cruzi infection are discussed.
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•Diagnostic techniques was evaluated in blood with Trypanosoma cruzi I, II, and IV.•Conventional PCR was the technique with the best performance to detect TcI strains.•The highest positivity rates of diagnostic tests were recorded for TcII strains.•ELISA immunoassay displays the greater detection capability for TcIV strains.•Association of methods increased the detection of the parasite for all DTUs.
Trypanosoma (Megatrypanum) theileri is a flagellated protozoan that infects ruminants and it displays high genetic diversity. In this study, we investigated the prevalence rates of this protozoan ...based on hemoculture and molecular diagnosis. The isolates of T. theileri thus obtained were characterized by molecular markers SSU rDNA and gGAPDH and molecular diagnosis based on Cathepsin L-like gene (PCR-TthCATL). The PCR-TthCATL and hemoculture indicated an overall prevalence rate of 8.13%, and the CATL derived sequence named IB was identified for the first time in cattle in the western Amazon region, as well as IF in Brazil. We also describe a possible new PCR-TthCATL derived sequence in cattle, designated IL.
Introduction: Neonatal sepsis is one of the most important causes of morbidity and mortality in preterm infants. Neonatal sepsis is defined as invasive bacterial infection that occurs in newborn ...children from the first to the ninetieth day of life. Hemoculture still represents the gold standard for the detection of sepsis. Blood culture may be falsely positive due to contamination of the samples. Contaminated blood cultures increase treatment costs and extend the length of stay of premature babies in hospitals. The aim of the study was to determine the incidence and risk factors of sepsis in premature infants who are being treated in the intensive care. Also to determine whether preventive medical-technical procedures will reduce the incidence of neonatal sepsis, as well as a reduction in contamination hemocultures. Materials and Methods: 239 premature infants have been analysed in whom the observed risk factors can lead to the onset neonatal sepsis. The preventive actions that could lead to a reduction of contamination in hemocultures have also been analysed. Results: The most common risk factors for sepsis is a small gestational age and body weight below 2000g. By using aseptic techniques for taking hemocultures there was a significant reduction in contamination of the same. Conclusion. Statistical analysis of the data identified the most common factors that lead to the occurrence of neonatal sepsis and proved the significance of the reduction of hemoculture contamination after the introduction of aseptic procedures and check lists.
An early diagnosis of typhoid fever caused by Salmonella typhi is difficult because of several spectra of clinical findings, identical to those of several other types of infections. A definitive ...diagnosis of typhoid fever is made by hemoculture as well as the Widal test. With pediatric patients, this life-threatening infection remains inherently long enough, demanding urgent attention. In typhoid fever, splenomegaly, enlarged mesenteric lymph nodes (MLNs), bowel wall thickening, acalculus cholecystitis, and hepatomegaly occur, which are diagnosed by the ultrasonography (USG) test. USG is a noninvasive, easily available, economical, fairly acceptable, and fairly sensitive test. The high-resolution real-time gray-scale USG method has simplified the evaluation of pathologic conditions, with remarkable clarity; consequently, an accurate assessment of the associated lesions can be done. In typhoid-endemic areas, USG findings as cited above could be used for diagnosis of typhoid fever, particularly when serology is equivocal and hemocultures are negative or not available. It was evident from USG studies that 12 of 52 patients had calculus cholecystitis; these individuals as well as eight patients without cholecystitis having hemocultures negative for S. typhi were excluded from the study. The rest of the cases (n=32) were included in this USG-based study for evaluation of features specific for typhoid fever. The following observations were recorded: splenomegaly in 32 patients, enlarged MLNs in 30 patients, bowel wall thickening in 25 patients, acalculus cholecystitis in 20 patients, and hepatomegaly in 10 patients. It can be concluded that these USG features—hepatosplenomegaly, enlarged MLNs, bowel wall thickening, and acalculus cholecystitis—should strongly favor the diagnosis of typhoid.
National guidelines from many countries recommend obtaining blood
culture from children with pneumonia upon hospitalization if the case is moderate
to severe. However, etiological, microbes, and ...health systems vary by country
and factors associated with bacteremia may also vary. We aimed to determine
the prevalence and identify factors associated with bacteremia among children
hospitalized with community-acquired pneumonia (CAP) in Thailand. We conducted
a prospective descriptive study. The study population was children aged
60 days to 15 years hospitalized with CAP at King Chulalongkorn Memorial
Hospital, Bangkok, Thailand from June 2014 to April 2015. We compared subject
with positive and negative blood cultures. One hundred fifty-two children with
CAP were recruited. Thirteen cases (8.6%) had a positive blood culture; 7 cases
(4.6%) with a positive blood culture were considered contamination, leaving 6
(3.9%) true positive cases. The isolated organisms were Streptococcus pneumoniae,
Escherichia coli, and Salmonella group B. Five factors were found to be associated
with bacteremia: 1) body temperature >38.5°C odds ratio (OR) = 9, 2) severe
sepsis status (OR = 27), 3) severe respiratory distress requiring mechanical ventilation
(OR = 145), 4) leukocytosis >17,000/μl (OR = 6), and 5) patchy infiltration
(OR=13). Children hospitalized with community acquired pneumonia have a low
rate of bacteremia. The prevalence of subjects in our study with bacteremia was
3.9% and there were 3 clinical and 2 laboratory factors significantly associated
with bacteremia. This study shows that hemoculture do not need to be routinely
performed in all children hospitalized with CAP.
Optimizar el manejo terapéutico de los pacientes adultos con cuadro clínico de bacteriemia posquirúrgica, ingresados es el objetivo de este trabajo. Es una investigación, descriptiva, retrospectiva ...en un universo de casos con edad igual o mayor a 15 años, ingresados y operados en el período comprendido desde el 1ro de enero de 1999 hasta 31 de diciembre de 2006. Los que tuvieron bacteriemia posquirúrgica constituyen la muestra. El 49 % de los pacientes tenía 60 años o más y de estos el 27,5 % eran del sexo femenino. Los diagnósticos de fractura o coxartrosis de cadera con sustitución endoprotésica parcial o total predominaron con el 27,5 y el 21,6 % respectivamente. La tasa de incidencia de bacteriemia clínica con hemocultivo positivo, fue de 12 por cada 10 000. Los estafilococos coagulasa positivos y estafilococos coagulasa negativos causaron más del 70 % de las bacteriemias, con un 39,2 y un 37,2 % respectivamente. Veinticinco o más de las 39 cepas de gérmenes grampositivos estudiadas hicieron resistencia a la cefazolina, la penicilina, la ceftriaxona, la ampicilina, la kanamicina y el sulfametoxazol + trimetoprim. De las 12 cepas de gérmenes gramnegativos estudiados seis o más se mostraron resistentes a la cefazolina, la ampicilina, la cefotaxima, la vancomicina, la gentamicina, la eritromicina y la estreptomicina. La mayoría eran mujeres que tenían 60 años o más, operadas de cadera ya sea por fractura o por coxartrosis, con implantación de prótesis parciales o totales, le siguieron los operados con diagnóstico de fractura abierta de tibia. Doce pacientes por cada 10 000 tenían riesgo de padecer bacteriemia primaria posquirúrgica confirmada microbiológicamente.
Primeiro isolado de Oligella urethralis em duas amostras de sangue periférico detectado por metodologia de monitoração contínua de metabolismo (sistema Bactec®) e identificado pelo sistema ...automatizado Phoenix® (BD System) em paciente com linfoma retroperitoneal com metástase em sistema nervoso central (SNC) no Hospital São Paulo da Universidade Federal de São Paulo (HSP/UNIFESP).First time isolation of Oligella urethralis in two samples of peripheral blood detected by continuous metabolism monitoring methodology (Bactec 61650 system) and identified by the automatized Phoenix 61650 system (BD System) in patient with retro-peritoneal lymphoma with metastasis in the central nervous system at São Paulo hospital of Federal University of São Paulo (HSP/UNIFESP).
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