Borja Gomez

Blood culture and bacteremia predictors in infants less than three months of age with fever without source.

Objectives: (1) To assess the rate of bacteremia in febrile infants less than 3 months of age admitted to a pediatric emergency department at a tertiary hospital; (2) to describe the bacteria isolated; and (3) to analyze factors related to increased probability of having a positive blood culture. Methods: A retrospective, cross-sectional, 5-year descriptive study that includes all infants less than 3 months of age who presented with fever without source (FWS) and had a blood culture performed. Results: A blood culture was performed in 1018 (91.5%) of 1125 infants admitted, and a bacterial pathogen was grown in 23 (2.2%) of these; 8 were associated with a positive urine culture. The most frequently isolated pathogen was Escherichia coli (9), followed by Streptococcus pneumoniae (4). The risk factors detected by multivariate analysis were: (a) being classified as “not well-appearing” (12.5% vs. 1.8%; odds ratio: 8.37) and (b) leukocyturia and/or nitrituria in a urine dipstick test (5.6% vs. 1.6%; odds ratio: 3.73). C-reactive protein value was higher than white blood cell count and absolute neutrophil count in detecting bacteremia; a 70 g/L cut-off had a specificity of 93.8%, but sensitivity of only 69.6%. Conclusions: A positive blood culture rate of 2.2% was found in infants less than 3 months of age with FWS. C-reactive protein, white blood cell count, and absolute neutrophil count were not good bacteremia predictors. We recommend obtaining a blood culture in infants less than 3 months of age with FWS, particularly those patients considered “not well-appearing” and those with leukocyturia and/or nitrituria.

Validation of the “Step-by-Step” Approach in the Management of Young Febrile Infants

BACKGROUND: A sequential approach to young febrile infants on the basis of clinical and laboratory parameters, including procalcitonin, was recently described as an accurate tool in identifying patients at risk for invasive bacterial infection (IBI). Our aim was to prospectively validate the Step-by-Step approach and compare it with the Rochester criteria and the Lab-score. METHODS: Prospective study including infants ≤90 days with fever without source presenting in 11 European pediatric emergency departments between September 2012 and August 2014. The accuracy of the Step-by-Step approach, the Rochester criteria, and the Lab-score in identifying patients at low risk of IBI (isolation of a bacterial pathogen in a blood or cerebrospinal fluid culture) was compared. RESULTS: Eighty-seven of 2185 infants (4.0%) were diagnosed with an IBI. The prevalence of IBI was significantly higher in infants classified as high risk or intermediate risk according to the Step by Step than in low risk patients. Sensitivity and negative predictive value for ruling out an IBI were 92.0% and 99.3% for the Step by Step, 81.6% and 98.3% for the Rochester criteria, and 59.8% and 98.1% for the Lab-score. Seven infants with an IBI were misclassified by the Step by Step, 16 by Rochester criteria, and 35 by the Lab-score. CONCLUSIONS: We validated the Step by Step as a valuable tool for the management of infants with fever without source in the emergency department and confirmed its superior accuracy in identifying patients at low risk of IBI, compared with the Rochester criteria and the Lab-score.

RAPID INFLUENZA TEST IN YOUNG FEBRILE INFANTS FOR THE IDENTIFICATION OF LOW-RISK PATIENTS

We included 381 febrile infants less than 3 months with a blood culture and a rapid influenza test done as part of study of fever. The prevalence of serious bacterial infections was significantly lower in patients in the positive rapid influenza test (RIT) group (3/113; 2.65%; 95% CI: 0–5.6) than in patients in the negative RIT group (47/268; 17.5%; 95% CI: 13–22.0). No patient with a positive RIT had a positive blood culture (vs. 8 in the negative RIT group, 2.98%, 95% CI: 0.9–5.0) The cerebrospinal fluid culture was positive in 5; all of them had a negative RIT. The use of RIT in the Emergency Department on previously well-appearing febrile young infants without a known source during influenza seasons can help to identify infants with a lower risk of developing serious bacterial infections. Routine blood culture may be no longer necessary in infants with a positive RIT.

Is 15 days an appropriate cut-off age for considering serious bacterial infection in the management of febrile infants?

Introduction: Febrile infants <3 months of age have a greater risk for serious bacterial infection (SBI). The risk is inversely correlated with age. Most protocols recommend admitting to hospital all febrile infants <28 days of age. However, as the prevalence of SBI is not homogenous in this age group, some authors have considered decreasing this cut-off age, allowing ambulatory management of selected patients meeting low-risk criteria. Objective: To determine whether 15 days is a suitable cut-off age for different approaches to the management of infants with fever. Patients and Methods: Cross-sectional descriptive study of infants <3 months of age with fever without a source seen between September 1, 2003 and August 30, 2010 in the pediatric emergency department of a tertiary teaching hospital. All infants <3 months of age with fever without a source (⩽38°C) were included. The following data were collected: age, sex, temperature, diagnosis, management in pediatric emergency department, and outcome. Results: Data were collected for 1575 infants; of whom, 311 (19.7%, 95% confidence intervals [CI]: 17.7–21.7) were found to have an SBI. The rate of SBI in the patients who were 15 to 21 days of age was 33.3% (95% CI: 23.7%–42.9%), similar to that among infants who were 7 to 14 days of age (31.9%, 95% CI: 21.1%–42.7%) and higher than among those older than 21 days of age (18.3%, 95% CI: 16.3–20.3%). Conclusions: Febrile infants 15 to 21 days of age had a rate of SBI similar to younger infants and higher than older age infants. It is not appropriate to establish the approach to management of infants with fever based on a cut-off age of 2 weeks.

Accuracy of a sequential approach to identify young febrile infants at low risk for invasive bacterial infection

Introduction Much effort has been put in the past years to create and assess accurate tools for the management of febrile infants. However, no optimal strategy has been so far identified. A sequential approach evaluating, first, the appearance of the infant, second, the age and result of the urinanalysis and, finally, the results of the blood biomarkers, including procalcitonin, may better identify low risk febrile infants suitable for outpatient management. Objective To assess the value of a sequential approach (‘step by step’) to febrile young infants in order to identify patients at a low risk for invasive bacterial infections (IBI) who are suitable for outpatient management and compare it with other previously described strategies such as the Rochester criteria and the Lab-score. Methods A retrospective comparison of three different approaches (step by step, Lab-score and Rochester criteria) was carried out in 1123 febrile infants less than 3 months of age attended in seven European paediatric emergency departments. IBI was defined as isolation of a bacterial pathogen from the blood or cerebrospinal fluid. Results Of the 1123 infants (IBI 48; 4.2%), 488 (43.4%) were classified as low-risk criteria according to the step by step approach (vs 693 (61.7%) with the Lab-score and 458 (40.7%) with the Rochester criteria). The prevalence of IBI in the low-risk criteria patients was 0.2% (95% CI 0% to 0.6%) using the step by step approach; 0.7% (95% CI 0.1% to 1.3%) using the Lab-score; and 1.1% (95% CI 0.1% to 2%) using the Rochester criteria. Using the step by step approach, one patient with IBI was not correctly classified (2.0%, 95% CI 0% to 6.12%) versus five using the Lab-score or Rochester criteria (10.4%, 95% CI 1.76% to 19.04%). Conclusions A sequential approach to young febrile infants based on clinical and laboratory parameters, including procalcitonin, identifies better patients more suitable for outpatient management.

Well appearing young infants with fever without known source in the emergency department: are lumbar punctures always necessary?

We included 685 consecutive previously healthy well appearing infants younger than 3 months with fever without known source admitted to an Emergency Department without routinely performing lumbar punctures (LP). LP was performed in 198 infants. Of these, 36 (18.1%) showed pleocytosis. Two infants less than 15 days were diagnosed with bacterial meningitis and 47 with aseptic meningitis (6.8%). LP was not performed in 487 infants. Of these, 69 were admitted to ward (46 had urinary tract infection) and 418 were discharged. In this group, we registered 38 unscheduled revisits to the Emergency Department (four aseptic meningitis). All infants did well. It is unnecessary to perform a LP routinely on infants over 1 month of age. The decision to perform the LP in previously healthy and well appearing infants with fever without known source attended by an experienced paediatric emergency physician can be individualized with no subsequent adverse outcomes. This approach may lead to under-diagnosing nonbacterial meningitis.

Prevalence and predictors of bacterial meningitis in young infants with fever without a source.

Background: Classical criteria differ when performing cerebrospinal fluid (CSF) analysis in infants younger than 90 days with fever without a source (FWS). Our objectives were to analyze the prevalence and microbiology of bacterial meningitis in this group and its prevalence in relation to clinical and laboratory risk factors. Methods: This is a substudy of a prospective registry including all infants of this age with FWS seen between September 2003 and August 2013 in a Pediatric Emergency Department of a Tertiary Teaching Hospital. Results: Lumbar puncture was performed in 639 (27.0%) of the 2362 infants with FWS seen, the rate being higher in not well-appearing infants [60.9% vs. 25.7%; odds ratio (OR), 4.49] and in those ⩽21 days old (70.1% vs. 20.4%; OR, 9.14). Eleven infants were diagnosed with bacterial meningitis: 9 were ⩽21 days old (prevalence 2.8% vs. 0.1%; OR, 30.42) and 5 were not well-appearing infants (5.7% vs. 0.2%; OR, 23.06). Bacteria isolated were Streptococcus agalactiae (3), Escherichia coli (3), Listeria monocytogenes (3), Streptococcus pneumoniae (1) and Neisseria meningitidis (1). None of the 1975 well-appearing infants >21 days old were diagnosed with bacterial meningitis, regardless of whether biomarkers were altered. Conclusions: In infants younger than 90 days with FWS, performing CSF analysis for ruling out bacterial meningitis must be strongly considered in not well-appearing infants and in those ⩽21 days old. The recommendation of systematically performing CSF analysis in well-appearing infants 22–90 days of age on the basis of analytical criteria alone must be reevaluated.

Outpatient management of selected young febrile infants without antibiotics

Objective To analyse the outpatient management of selected febrile infants younger than 90 days without systematic lumbar puncture and antibiotics. Methods A prospective registry-based cohort study including all the infants ≤90 days with fever without a source (FWS) who were evaluated in a paediatric emergency department (ED) over a 7-year period (September 2007–August 2014). We analysed the outcome of those infants with low-risk criteria for serious bacterial infection (SBI) managed as outpatients without antibiotics and without undergoing a lumbar puncture. Low-risk criteria: Well appearing, older than 21 days of age, no leucocyturia, absolute neutrophil count ≤10 000, serum C reactive protein ≤20 mg/L, procalcitonin <0.5 ng/mL and no clinical deterioration during the stay in the ED (always <24 hours). Results 1472 infants with FWS attended the ED. Of these, 676 were classified to be at low risk for SBI without performing a lumbar puncture. After staying <24 hours in the short-stay unit of the ED, 586 (86.6%) were managed as outpatients without antibiotics. Two patients were diagnosed with SBI: one occult bacteraemia and one bacterial gastroenteritis. Both were afebrile when evaluated again and did well. No patient returned to the ED due to clinical deterioration. Fifty-one infants (8.7%) returned to the ED mainly due to persistence of fever or irritability. None was diagnosed with definite SBI or non-bacterial meningitis. Conclusions Outpatient management without antibiotics and systematic lumbar puncture is appropriate for selected febrile infants younger than 3 months of age with close follow-up.

Using a urine dipstick to identify a positive urine culture in young febrile infants is as effective as in older patients

There is limited evidence about the diagnostic value of urine dipsticks in young febrile infants. The aim of this study was to determine whether urine dipsticks would identify positive urine cultures in febrile infants of less than 90 days of age.

Invasive bacterial infections in a paediatric emergency department in the era of the heptavalent pneumococcal conjugate vaccine.

Objective To describe the characteristics of patients diagnosed with invasive bacterial infections (IBIs) in a Paediatric Emergency Department (PED) following the introduction of the heptavalent pneumococcal conjugated vaccine (PCV7). Methods Descriptive retrospective study of children under 14 years of age diagnosed with IBIs in a PED of a tertiary hospital between January 2008 and December 2009. Results In this period we registered 123 396 episodes and 59 patients who were diagnosed with IBIs (22 patients under 1 year of age, 37.2%). Of these, 11 (18.6%) had some severe underlying condition and 38 (64.4%) were stable on arrival. The most common diagnoses were sepsis with/without meningitis (23, 38.9%) and bacteraemia (14, 23.7%), while the pathogens most frequently isolated were Streptococcus pneumoniae (23, 38.9%) and Neisseria meningitidis (18, 30.5%). Pathogens were isolated from blood in 57 patients and from the cerebrospinal fluid in eight (in these, the same bacterial species was isolated in the blood, except for two cases with S. pneumoniae). Of the pneumococci isolated, 80% corresponded to serotypes included in the 13-valent PCV13. In seven cases, pathogens were detected using only PCR analysis (N. meningitidis, four; S. pneumoniae, three). Twenty-five patients were admitted to the Paediatric Intensive Care Unit. No patient died but two had sequelae. Conclusion In the era of PCV7, pneumococcus is the leading cause of IBI in PED. The introduction of PCV13 may lead to a very significant decrease in the IBI rate and meningococcus may become the leading cause of IBI.