Management of febrile outpatient neonates

Evaluation and Management of Well-Appearing Febrile Infants 8 to 60 Days Old

This guideline addresses the evaluation and management of well-appearing, term infants, 8 to 60 days of age, with fever ≥38.0°C. Exclusions are noted. After a commissioned evidence-based review by the Agency for Healthcare Research and Quality, an additional extensive and ongoing review of the literature, and supplemental data from published, peer-reviewed studies provided by active investigators, 21 key action statements were derived. For each key action statement, the quality of evidence and benefit-harm relationship were assessed and graded to determine the strength of recommendations. When appropriate, parents' values and preferences should be incorporated as part of shared decision-making. For diagnostic testing, the committee has attempted to develop numbers needed to test, and for antimicrobial administration, the committee provided numbers needed to treat. Three algorithms summarize the recommendations for infants 8 to 21 days of age, 22 to 28 days of age, and 29 to 60 days of age. The recommendations in this guideline do not indicate an exclusive course of treatment or serve as a standard of medical care. Variations, taking into account individual circumstances, may be appropriate.

Threshold for defining fever varies with age, especially in children: A multi-site diagnostic accuracy study

Aim

The American Academy of Pediatrics and the European Centre for Pediatric and Adolescent Medicine guideline define fever as a temperature >38.0°C for all ages and recommend use of rectal thermometers in children <3 years. Based on new literature, this definition of fever using a fixed threshold of 38.0°C needs to be re‐examined.

Design

A multi‐site diagnostic accuracy study was conducted to compare an “age‐based” threshold model with a “fixed” threshold over 38.0°C on a total of 894 patients of which 373 were ill.

Methods

The “age‐based” and “fixed” threshold fever determinations were then compared to a clinical categorization (“well” or “ill”) conducted by a clinician through a comprehensive examination.

Results

The sensitivity and accuracy for the age‐based thresholds were found to be superior to the fixed thresholds in all ages and current ear thermometers were found equivalent to rectal thermometers in infants <6 months.

Association of Cough Status With Bacterial Infections in Febrile Infants

OBJECTIVES

To examine the association between cough status and bacterial infections (BIs) to more accurately stratify risk and predict BIs in febrile infants.

METHODS

A retrospective cohort study was performed by identifying all infants ≤60 days old with temperature ≥38°C at an urban pediatric emergency department from 2014 to 2016. The Rochester Risk model was used to stratify risk. Cough status (with or without) was the main covariate of interest. The primary outcome was a BI, including urinary tract infection, bacteremia, or meningitis. Analyses consisted of descriptive statistics, simple and multiple regression to compare the odds of BI on the basis of cough status, as well as χ² statistics to compare the BI rates among high-risk infants with and without cough.

RESULTS

Of 508 febrile infants ≤60 days old, 46 (9.1%) had a BI, 13 of which were either bacteremia or meningitis. There were no BIs among low-risk infants with a cough. The odds of BI increased progressively, peaking at 14.6 (95% confidence interval: 4.3-49.7) for high-risk infants without a cough. The adjusted odds of BI among infants with cough was 0.47 (95% confidence interval: 0.22-0.99).

CONCLUSIONS

In our findings, an inverse relationship is demonstrated between presence of cough and odds of BI, suggesting that cough status may be a useful marker of viral infections in febrile infants. Considering that detecting cough status is noninvasive, inexpensive, and immediately available, it represents an attractive value-based risk factor to enhance current BI prediction models.

Managing Febrile Infants

The authors hypothesized that sepsis workup recommendations are associated with practice recommendations published during the physician’s residency. The first published recommendations suggesting sepsis workups for nontoxic, young, febrile infants appeared in pediatric journals from 1975-1980 and in family practice journals from 1981-1987. Data are from the Community Tracking Study (3,272 pediatricians and 2,432 family physicians). “Percentage of sepsis workups recommended” was defined by response to a vignette about the percentage of well-appearing 6-week-old children with a fever of 101°F for whom the physician would recommend a sepsis workup. Multivariable regression with piecewise linear functions evaluated workup recommendations by timing of literature recommendations during residency. Pediatricians recommended sepsis workups 81.6% of the time and family physicians 67.7% (p < .001). Increased recommendations occurred among pediatricians who completed residency from 1975-1980 (p < .05) and among family physicians who completed residency from 1981-1987 (p < .005), when specialty-specific journals published recommendations for sepsis workups for febrile infants. The association between publication of sepsis workup recommendations during a physician’s residency and increased sepsis workup recommendations suggests an unrecognized and enduring impact of such publications.

A survey of the management of febrile infants in pediatric emergency departments

OBJECTIVE

To determine whether emergency departments (EDs) at pediatric emergency medicine (PEM) fellowship training institutions have a departmental policy regarding the evaluation and management of febrile infants and if reported policies are based on published guidelines (PGs).

METHODS

A 32-item telephone survey was administered to PEM fellowship directors (FDs). Departmental demographics and criteria used to evaluate febrile infants were collected. Scenarios were presented regarding the evaluation and management of low-risk febrile infants. Reported consistency among ED attending physicians at the same institution was also assessed.

RESULTS

The response rate was 83% (53 of 64). Fifty-one percent (26 of 53) of FDs reported the existence of a departmental policy regarding the evaluation of febrile infants. Of those who have a departmental policy, 19% (5 of 26) stated that it was one of the PGs. The FDs who reported the existence of a departmental policy were significantly more likely to report consistent management by all ED attending physicians in their department compared with those without a departmental policy (81% vs 19%, P < 0.05). The most frequent age and temperature cutoff for a mandatory sepsis evaluation were 28 days (45%, 28 of 53) and 100.4°F (66%, 35 of 53). The FDs reported a lack of consistency among ED attending physicians at the same institution regarding age and temperature (66% and 17% of the time, respectively). Eighty-five percent (45 of 53) of FDs reported that a new guideline is needed.

CONCLUSIONS

Nearly one half of EDs at PEM fellowship training institutions are reported not to have a departmental policy regarding the management of febrile infants, and departmental policies rarely conform to any of the PGs. There is substantial interdepartmental and intradepartmental practice variability regarding the management of febrile infants and a strong consensus regarding the need for a new guideline.

Diagnosis and evaluation of febrile infants under 4 months of age in Japan by using RT-PCR for enterovirus

OBJECTIVES AND METHODS

In order to establish an effective management for febrile infants under 4 months of age we analysed the causes of fever by using bacterial work up and a highly sensitive RT-PCR method during a 3-year-period. From February 1998 to January 2001, 263 infants under 4 months of age were admitted to our hospital because of fever (>38.0 degrees C) and enrolled in this study.

RESULTS

Eighty-nine cases (33.8%) were diagnosed as lower respiratory infections, and 62 (23.5%) as urinary tract infections. Aseptic meningitis was found in 35 cases (13.2%) and fever of unknown origin in 22 (8.3%). Sepsis and purulent meningitis were found in three and two infants, respectively. Aseptic meningitis was the most common disease in infants below 30 days. Aseptic meningitis and fever of unknown origin revealed no seasonable tendency. Twelve cases out of 20 tested infants with aseptic meningitis showed positive results for enterovirus in CSF.

CONCLUSION

Clinicians should consider age, sex and seasons when evaluating and treating infants with fever. Previously lumbar puncture, urinalysis and chest X-ray were recommended to avoid useless assays. These results also revealed that RT-PCR is a useful and significant assay to establish an exact diagnosis in very young infants.

[Factors predicting serious bacterial infections in febrile infants less than three months old: multivariate analysis]

AIM

To identify predictive factors of the presence of a serious bacterial infection (SBI) in febrile infants less than three months old.

METHODS

Retrospective analysis of the medical files of 315 consecutive consultations of febrile infants less than three months old in the pediatric emergency department of a French hospital, with logistic regression multivariate analysis of the different criteria routinely considered and C-reactive protein (CRP).

RESULTS

SBI were diagnosed in 79 (25.1%) infants, primarily urinary tract infections (71; 22.5%). One of these 79 children had pneumococcal meningitis but met the classical criteria for low risk of SBI: he died because antibiotics were not prescribed sufficiently early. Factors significantly associated with SBI were: male sex; temperature >38.5 degrees C and lasting >24 hours; poor general condition; absence of ear, nose and throat symptoms; high white blood cell count with >50% neutrophils; and serum CRP concentration >20 mg/l. Multivariate analysis entering all these items retained only the latter two (respectively, OR: 13.5, 95% CI: [6.5-28.2] and OR: 2.9; 95% CI: [1.3-6.3]). CRP <20 mg/l and <50% neutrophils had a negative-predictive value of 93.1% for the absence of SBI.

CONCLUSIONS

At present, no factor(s) is(are) able to predict with 100% accuracy the absence of SBI in febrile infants less than three months old. The risk of severe sequelae or death caused by untreated SBI would seem to justify the prescription of antibiotics until microbacterial culture results become available.

Does leucocytosis identify bacterial infections in febrile neonates presenting to the emergency department?

OBJECTIVE

This study was undertaken to evaluate the discriminatory power of the peripheral white blood cell (WBC) count to identify bacterial infections in a cohort of febrile neonates (<or=28 days of age) presenting to an emergency department.

METHODS

Retrospective medical record review using descriptive statistics and a receiver operating characteristic (ROC) curve. Neonates who presented to a tertiary care paediatric emergency department between 1 January 1999 and 22 August 2002, had a temperature >or=38 degrees C, underwent lumbar puncture, and had a WBC count obtained were included. They were divided according to microbiological and radiographic findings into four groups: bacterial infections, viral infections, pneumonia, and negative sepsis evaluations.

RESULTS

A total of 69 febrile neonates met the inclusion criteria. The number of neonates in each group was as follows: 8 with bacterial infections, 10 with viral infections, 3 with pneumonias, and 48 with negative sepsis evaluations. There was substantial overlap in WBC counts among the groups. The area under the ROC curve was 0.7231 (95% CI 0.5665 to 0.8797).

CONCLUSION

In a cohort of febrile neonates evaluated in the emergency department, the WBC count had modest discriminatory power in identifying neonates with bacterial infections and demonstrated substantial overlap among groups. The present data suggest against the use of any WBC count threshold to identify bacterial infections in febrile neonates presenting to the emergency department.

Hyperpyrexia among infants younger than 3 months

OBJECTIVE

To determine the prevalence of serious bacterial infection in infants younger than 3 months with fever > or =40 degrees C.

METHODS

We retrospectively identified all infants younger than 3 months with fever who presented to a pediatric emergency department. The medical records were reviewed. The prevalence of serious bacterial infection (SBI) among those patients with hyperpyrexia was compared with febrile infants with lower fever.

RESULTS

5279 infants younger than 3 months with fever were reviewed. Ninety-eight patients (1.7%) had triage temperature > or =40 degrees C rectally. Median age, temperature, and white blood count for those with hyperpyrexia were 58 days (interquartile range [IQR] 36-78 days), 40.2 degrees C (IQR, 40.0-40.4 degrees C), and 10,800/mm3 (IQR, 7900-14,600/mm3), respectively. Diagnostic studies included blood culture (100%), urine culture (100%), lumbar puncture (100%), chest radiographs (34%), and stool cultures (11%). SBI was found in 38% infants with hyperpyrexia: urinary tract infection was the most common SBI (71%). Among patients with hyperpyrexia, patients with SBI had similar mean white blood cell counts (14,000 vs. 10,200 cells/mm3) and age (54 vs. 53 days) as those with hyperpyrexia but no SBI. The prevalence of SBI among febrile infants with temperatures > or =40.0 degrees C was 38% (95% CI 27-48%) compared with those with fever < or =40 degrees C: 8.8% (95% CI 8.1-9.5%).

CONCLUSION

Hyperpyrexia is rare among febrile infants younger than 3 months. One-third of infants with temperature > or =40.0 degrees C had SBI. Future management algorithms might include hyperpyrexia as a risk factor for serious infection.

Risk of serious bacterial infection in young febrile infants with respiratory syncytial virus infections

BACKGROUND

The evaluation of young febrile infants is controversial, in part because it is unclear whether clinical evidence of a viral infection significantly reduces the risk of serious bacterial infections (SBIs). Specifically, it remains unclear whether the risk of SBI is altered in a meaningful way in the presence of respiratory syncytial virus (RSV) infections.

OBJECTIVE

The objective of this study was to determine the risk of SBI in young febrile infants who are infected with RSV compared with those without RSV infections.

METHODS

We conducted a 3-year multicenter, prospective, cross-sectional study. All febrile (> or =38 degrees C) infants who were < or =60 days of age and presented to any of 8 pediatric emergency departments from October through March 1998-2001 were eligible. General clinical appearance was evaluated using the Yale Observational Scale. We determined RSV status by antigen testing of nasopharyngeal secretions. We defined bronchiolitis as either wheezing alone or chest retractions in association with an upper respiratory infection. We evaluated infants with blood, urine, cerebrospinal fluid, and stool cultures. Urinary tract infection (UTI) was defined by single pathogen growth of > or =5 x 10(4) cfu/mL, or > or =10(4) cfu/mL in association with a positive urinalysis in a catheterized specimen, or > or = 10(3) cfu/mL in a suprapubic aspirate. Bacteremia, bacterial meningitis, and bacterial enteritis were defined by growth of a known bacterial pathogen. SBI was defined as any of the above-mentioned 4 bacterial infections.

RESULTS

We enrolled 1248 patients, including 269 (22%) with RSV infections. The overall SBI status could be determined in 1169 (94%) of the 1248 patients, and the rate of SBIs was 11.4% (133 of 1169; 95% confidence interval [CI]: 9.6%-13.3%). The rate of SBIs in the RSV-positive infants was 7.0% (17 of 244; 95% CI: 4.1%-10.9%) compared with 12.5% (116 of 925; 95% CI: 10.5%-14.8%) in the RSV-negative infants (risk difference: 5.5%; 95% CI: 1.7%-9.4%). The rate of UTI in the RSV-positive infants was 5.4% (14 of 261; 95% CI: 3.0%-8.8%) compared with 10.1% (98 of 966; 95% CI: 8.3%-12.2%) in the RSV-negative infants (risk difference: 4.7%; 95% CI: 1.4%-8.1%). The RSV-positive infants had a lower rate of bacteremia than the RSV-negative infants (1.1% vs 2.3%; risk difference: 1.2%; 95% CI: -0.4% to 2.7%). No RSV-positive infant had bacterial meningitis (0 of 251; 95% CI: 0%-1.2%); however, the differences between the 2 groups with regard to bacteremia and bacterial meningitis did not achieve statistical significance.

CONCLUSIONS

Febrile infants who are < or =60 days of age and have RSV infections are at significantly lower risk of SBI than febrile infants without RSV infection. Nevertheless, the rate of SBIs, particularly as a result of UTI, remains appreciable in febrile RSV-positive infants.

Fever in healthy asymptomatic newborns during the first days of life

OBJECTIVE

To determine the characteristics of febrile full term infants during the first days of life, and to discover the rate of serious bacterial infections among low risk neonates with systemic fever.

DESIGN

A retrospective case-control study of 122 cases and 122 controls in a single institution.

RESULTS

Weight loss, breast feeding, caesarean section delivery, and high birth weight were found to be the most significant predictors of developing fever during the first days of life. Of the 122 patients in the study group, only one had a serious bacterial infection (a positive urine culture for group B streptococcus).

CONCLUSIONS

In low risk full term infants, fever with no other symptoms during the first days of life (but after the first day) is related primarily to dehydration, breast feeding, caesarean section, and high birth weight. Infection is the least common explanation.

Management of fever in infants and children

There is no question that fever is a source of great consternation for parent and physician alike; however, it is impossible to predict with certainty the outcome of every febrile illness. Inherent in the words diagnostic impression is a degree of uncertainty. The only question remaining is how much uncertainty is in the best interest of the child. Physicians try to use the existing scientific data to best determine the prevalence of disease and outcome. At the same time, they must recognize the limitations of both the data and their ability to be generalized to every population. Everything clinicians do has risks and costs, which they must balance against the incidence of complications and the benefits of testing. To take away clinical judgment makes physicians technicians not clinicians.

Predictive model for serious bacterial infections among infants younger than 3 months of age

OBJECTIVE

To develop a data-derived model for predicting serious bacterial infection (SBI) among febrile infants <3 months old.

METHODS

All infants </=90 days old with a temperature >/=38.0 degrees C seen in an urban emergency department (ED) were retrospectively identified. SBI was defined as a positive culture of urine, blood, or cerebrospinal fluid. Tree-structured analysis via recursive partitioning was used to develop the model. SBI or No-SBI was the dichotomous outcome variable, and age, temperature, urinalysis (UA), white blood cell (WBC) count, absolute neutrophil count, and cerebrospinal fluid WBC were entered as potential predictors. The model was tested by V-fold cross-validation.

RESULTS

Of 5279 febrile infants studied, SBI was diagnosed in 373 patients (7%): 316 urinary tract infections (UTIs), 17 meningitis, and 59 bacteremia (8 with meningitis, 11 with UTIs). The model sequentially used 4 clinical parameters to define high-risk patients: positive UA, WBC count >/=20 000/mm(3) or </=4100/mm(3), temperature >/=39.6 degrees C, and age <13 days. The sensitivity of the model for SBI is 82% (95% confidence interval [CI]: 78%-86%) and the negative predictive value is 98.3% (95% CI: 97.8%-98.7%). The negative predictive value for bacteremia or meningitis is 99.6% (95% CI: 99.4%-99.8%). The relative risk between high- and low-risk groups is 12.1 (95% CI: 9.3-15.6). Sixty-six SBI patients (18%) were misclassified into the lower risk group: 51 UTIs, 14 with bacteremia, and 1 with meningitis.

CONCLUSIONS

Decision-tree analysis using common clinical variables can reasonably predict febrile infants at high-risk for SBI. Sequential use of UA, WBC count, temperature, and age can identify infants who are at high risk of SBI with a relative risk of 12.1 compared with lower-risk infants.

Management of fever without source in infants and children

Twenty percent of febrile children have fever without an apparent source of infection after history and physical examination. Of these, a small proportion may have an occult bacterial infection, including bacteremia, urinary tract infection (UTI), occult pneumonia, or, rarely, early bacterial meningitis. Febrile infants and young children have, by tradition, been arbitrarily assigned to different management strategies by age group: neonates (birth to 28 days), young infants (29 to 90 days), and older infants and young children (3 to 36 months). Infants younger than 3 months are often managed by using low-risk criteria, such as the Rochester Criteria or Philadelphia Criteria. The purpose of these criteria is to reduce the number of infants hospitalized unnecessarily and to identify infants who may be managed as outpatients by using clinical and laboratory criteria. In children with fever without source (FWS), occult UTIs occur in 3% to 4% of boys younger than 1 year and 8% to 9% of girls younger than 2 years of age. Most UTIs in boys occur in those who are uncircumcised. Occult pneumococcal bacteremia occurs in approximately 3% of children younger than 3 years with FWS with a temperature of 39.0 degrees C (102.2 degrees F) or greater and in approximately 10% of children with FWS with a temperature of 39.5 degrees C (103.1 degrees F) or greater and a WBC count of 15, 000/mm(3) or greater. The risk of a child with occult pneumococcal bacteremia later having meningitis is approximately 3%. The new conjugate pneumococcal vaccine (7 serogroups) has an efficacy of 90% for reducing invasive infections of Streptococcus pneumoniae. The widespread use of this vaccine will make the use of WBC counts and blood cultures and empiric antibiotic treatment of children with FWS who have received this vaccine obsolete.

Time to detection of positive cultures in 28- to 90-day-old febrile infants

OBJECTIVE

To determine the time to detection of positive blood, urine, and cerebrospinal fluid (CSF) cultures among febrile 28- to 90-day-old infants.

STUDY DESIGN

Retrospective cohort of consecutive 28- to 90-day-old infants presenting with a temperature of >/=38 degrees C to an urban pediatric emergency department. Positive cultures and times to detection were noted. Patients were categorized as being at high risk for serious bacterial illness (SBI) based on clinical and laboratory criteria.

RESULTS

Of the 3166 febrile infants seen in the emergency department during the study, 2733 had blood (86%), 2517 had urine (80%), and 2361 had CSF (75%) specimens obtained for culture, and 2190 had all 3 cultures (69%) sent. There were 224 positive cultures in 214 patients; of these, 191 had all 3 cultures (89%) sent. Subsequent analyses were confined to those who had all 3 cultures sent. The detected rate of SBI was 8.7% (191/2190). There were 28 positive blood cultures (1. 3%), 165 positive urine cultures (7.5%), and 8 positive CSF cultures (.4%). Median time to detection of positive cultures was 16 hours for blood, 16 hours for urine, and 18 hours for CSF. Four blood cultures (.1%), 20 urine cultures (.9%), and 0 CSF cultures were noted to have growth of a pathogen >24 hours after the specimen was obtained. All 4 blood cultures and 17 of 20 urine cultures with growth noted after 24 hours occurred among high-risk patients.

CONCLUSIONS

The risk of identifying SBI after 24 hours is 1.1% among all 28- to 90-day-old febrile infants and.3% in low-risk infants.

Urinary tract infection in febrile infants younger than eight weeks of Age

OBJECTIVE

To assess the usefulness of laboratory parameters, including peripheral white blood cell (WBC) count, C-reactive protein (CRP) concentration, erythrocyte sedimentation rate (ESR), and microscopic urinalysis (UA), for identifying febrile infants younger than 8 weeks of age at risk for urinary tract infection (UTI), and comparison of standard UA and hemocytometer WBC counts for predicting the presence of UTI.

METHODS

A total of 162 febrile children <8 weeks of age were enrolled in this prospective study. All underwent clinical evaluation and laboratory investigation, including WBC count and differential; ESR; CRP; blood culture; a lumbar puncture for cell count and differential, glucose level, protein level, Gram stain, and culture; and a UA and urine culture. All urine specimens were obtained by suprapubic aspiration and microscopically analyzed with standard UA as well as with hemocytometer WBC counts. Quantitative urine cultures were performed. Sensitivity, specificity, accuracy, likelihood ratios, and receiver operating characteristic (ROC) curves were determined for each of the screening tests.

RESULTS

There were 22 positive urine culture results of at least 100 colony-forming unit/mL. Eighteen of these 22 patients were males, and all were uncircumcised. There were significant differences for pyuria >/=5 WBCs/hpf, pyuria >/=10 WBC/microL, CRP >20 mg/L, and ESR >30 mm/hour between culture-positive and culture-negative groups (P <.05). The ROC area for hemocytometer WBC count, standard UA, peripheral WBC count, ESR, and CRP concentration were.909 +/-.045,.791 +/-.065,.544 +/-.074,. 787 +/-.060, and.822 +/-.036, respectively. The ROC curve analysis indicates that the CRP, ESR, and standard UA were powerful but imperfect tools with which to discriminate for UTI in potentially infected neonates. Hemocytometer WBC counts had the highest sensitivity, specificity, accuracy, and likelihood ratios for identifying very young infants with positive urine culture results. For all assessments, hemocytometer WBC counts were significantly different, compared with the standard urinalysis. ESR, CRP, and peripheral WBC counts were not helpful in identifying UTI in febrile infants.

CONCLUSION

UTI had a prevalence of 13.6% in febrile infants <8 weeks of age. The CRP, ESR, and standard UA were imperfect tools in discriminating for UTI, and the sensitivity of these laboratory parameters was relatively low. Hemocytometer WBC count was a significantly better predictor of UTI in febrile infants.

Evaluation and management of infants with fever

Fever is an important symptom in children. In infants younger than 2 months of age, fever might be the only indicator of bacterial disease. Critical to the well-being of these infants is that the physician understand the importance of the occurrence of fever within the first 2 months of life and appropriately investigate the causes of fever. Although all infants with fever require comprehensive evaluation for bacterial disease, not all require hospitalization or empiric treatment with antibiotics. Febrile infants 1 to 2 months of age who, after comprehensive clinical and laboratory evaluation, are found to have no other findings that place them in a higher-risk category for bacterial disease are candidates for continuing observation as outpatients. This management option should be restricted to selected infants whose caretakers and primary physicians agree with and are able to carry out such a plan.

Predictors of physician compliance with a published guideline on management of febrile infants

BACKGROUND

Previous studies have demonstrated clinicians' poor compliance with published management strategies and protocols, but the reasons why physicians often choose to vary their management of the febrile infant from published guidelines are poorly understood.

OBJECTIVE

We conducted a study of physicians to learn more about the issues that influence their decisions in the management of febrile infants.

METHODS

A survey study of pediatricians, emergency physicians and family physicians randomly selected from a list of licensed physicians in the United States. Chi square and Kruskal-Wallis tests were used to measure differences in responses by specialty. Odds ratios from logistic regression were used to measure differences in compliance with a recently published guideline.

RESULTS

We received 193 completed surveys from pediatricians, 177 from emergency physicians and 104 from family physicians. After controlling for other variables, odds for compliance with a recently published guideline were higher for pediatricians [odds ratio (OR) = 9.13] and emergency physicians (OR = 2.5) than for family physicians (P < 0.001). Factors associated with decreased odds of compliance included more years since graduation from medical school (OR = 0.93), a higher proportion of office visits by children < 1 year of age (OR = 0.97) and increased comfort diagnosing serious bacterial illness (OR = 0.35). Factors associated with increased odds of compliance included a higher perceived likelihood of serious bacterial illness in febrile infants (OR = 1.01) and better reported knowledge of the recently published guideline (OR = 2.01).

CONCLUSIONS

We found that specialty as well as other factors were associated with physician compliance with a recently published guideline. This information may facilitate guideline development and implementation by providing a better understanding of what motivates physicians in their clinical decision making.

The efficacy of routine outpatient management without antibiotics of fever in selected infants

BACKGROUND

A previous study produced a protocol for outpatient management of febrile infants (FIs) judged to be at low risk for serious bacterial illness (SBI). This Philadelphia protocol demonstrated that 40% of FIs seen in the emergency department could be safely managed without antibiotics at home; and it was established by the emergency department staff as the standard of care at our institution.

OBJECTIVE

To determine 1) the actual practices of management of FIs 18 months after establishment of the Philadelphia protocol as the standard of care, and 2) the continued efficacy of noninvasive outpatient management of fever in FIs who, using the Philadelphia protocol, were identified as low risk for SBI.

DESIGN

Thirty-six-month consecutive cohort study.

SETTING

Urban pediatric emergency department.

PARTICIPANTS

Four hundred twenty-two infants, 29 to 60 days of age, with rectal temperatures >/=38.0 degrees C. Interventions. After a complete history taking, physical examination, and workup for SBI, infants were managed at the discretion of the attending physician in the emergency department. Subsequently, those management practices were reviewed and compliance with the Philadelphia protocol was evaluated. In addition, the overall efficacy and safety of that standard during 8 years of use was assessed.

RESULTS

Of the 422 FIs enrolled, 101 (24%) were prospectively identified as low risk for SBI, and safe for management without antibiotics. Twenty-eight (6%) FIs were managed out of accordance with the Philadelphia protocol. Seven were admitted out of accordance, 10 (2 with UTI) were discharged out of accordance, and 11 inpatients (1 with bacterial gastroenteritis) initially received no antibiotics out of accordance with the protocol. Physician failure to consider the results of the complete blood count or urinalysis accounted for errors involving FIs with SBI. None of the 43 FIs with SBI were identified by the Philadelphia protocol to be at low risk for SBI.

CONCLUSIONS

The Philadelphia protocol for outpatient management without antibiotics of FIs at low risk for SBI remains practical, reliable, and safe. Because breaches do occur, physicians must carefully scrutinize protocol compliance, especially with regard to the complete blood count and urinalysis.

Evaluation of the infant with fever without source: an evidence based approach

The infant with fever without an obvious source upon physical examination offers a challenging clinical problem. A combination of detailed history, physical examination, and selected laboratory tests allows the clinician to discern which infants are at lower risk for bacterial illness. Implications for management and future research are discussed herein.

Identification of febrile neonates unlikely to have bacterial infections

OBJECTIVE

A prospective study was undertaken to evaluate the usefulness of low risk criteria for identifying febrile neonates unlikely to have bacterial infections, particularly bacteremia and meningitis. Using these criteria we wished to check whether these low risk neonates can be safely managed as inpatients under close observation but without receiving empiric antibiotic therapy.

STUDY DESIGN

We conducted a prospective study of 250 consecutive infants 28 days of age or less (range, 4 to 28 days) who had rectal temperatures of at least 38 degrees C. After a complete history, physical examination and sepsis workup, the 131 febrile neonates with clinical and laboratory findings indicating low risk for bacterial infections were hospitalized, closely observed and not given antibiotics. The low risk criteria used to identify these neonates included well appearance; absence of physical signs of an ear, eye or soft tissue infection; a white blood cell count of 5000 to 15,000/mm3, a neutrophil band form count of < 1500/mm3, a spun urine specimen that had < 10 white blood cells per high power field on microscopy and a C-reactive protein value of < 20 mg/l. The remaining 119 febrile neonates who did not meet the low risk criteria were hospitalized and given empiric antibiotics pending culture results.

RESULTS

The overall incidence of bacterial infections in the 250 febrile neonates was 16.4% (41 neonates) with bacteremia and/or meningitis occurring in 4.4% (11 neonates). Of the 131 low risk neonates only one (0.8%) had a bacterial infection (urinary tract infection) compared with 40 (33.6%) among the 119 who did not meet the criteria (P < 0.05). The negative predictive value of these criteria for excluding bacterial infections was 99.2% (95% confidence interval, 97.7% to 100%). For bacteremia and meningitis this figure became 100%. However, the positive predictive value and specificity of the criteria were too low to identify all febrile neonates with bacterial infections. Among the low risk group 58 (44.3%) were reclassified on the second or third hospital day, because of continued fever (35), poor activity (14) and white blood cell count > 15000/mm3 on a repeat blood test (9). They were given antibiotics, but only 1 had a urinary tract infection. This patient was then treated with a 7-day course of antibiotics. All low risk neonates recovered uneventfully with no relapses observed during their hospital stay or at the time of minimum 1-week outpatient follow-up visits.

CONCLUSION

By the low risk criteria a substantial number of febrile neonates at low risk for bacterial infections can be identified and managed safely as inpatients without antibiotic therapy.

Initial approach to the infant younger than 2 months of age who presents with fever

Fever is common in infants presenting to their physicians for evaluation. Infants younger than 2 months of age are at increased risk of SBI because of their exposure to different pathogens and because of their immature immune systems. The bacteria that may infect them include E coli, group B Streptococcus, and L monocytogenes, as well as Pneumococcus, Neisseria meningitidis, S aureus, and H influenzae. They are also susceptible to viruses, parasites, and fungi. Clinical characteristics associated with increased risk of SBI have been identified. Infants who are ill-appearing, have abnormal hemograms or urinalyses, or have evidence of bacterial infection on physical examination are at higher risk. There has been an association of very high fever with SBI, although this has been inconclusive. Clinical judgment is important, although not always completely reliable in ruling out SBI. Young infants with fever should be evaluated with a thorough history, physical examination, and selected laboratory studies. Those younger than 29 days of age should usually be admitted for observation and parenteral antibiotics. Infants from 29 to 60 days of age may be evaluated carefully and considered for outpatient management, either with or without antibiotics.

Outpatient management without antibiotics of fever in selected infants

BACKGROUND

In many academic centers it is standard practice to hospitalize all febrile infants younger than two months of age, whereas in community settings such infants are often cared for as outpatients.

METHODS

We conducted a controlled study of 747 consecutive infants 29 through 56 days of age who had temperatures of at least 38.2 degrees C. After a complete history taking, physical examination, and sepsis workup, the 460 infants with laboratory or clinical findings suggestive of serious bacterial illness were hospitalized and treated with antibiotics. The screening criteria for serious bacterial illness included a white-cell count of at least 15,000 per cubic millimeter, a spun urine specimen that had 10 or more white cells per high-power field or that was positive on bright-field microscopy, cerebrospinal fluid with a white-cell count of 8 or more per cubic millimeter or a positive Gram's stain, or a chest film showing an infiltrate. The 287 infants who had unremarkable examinations and normal laboratory results were assigned to either inpatient observation without antibiotics (n = 148) or outpatient care without antibiotics but with reexaminations after 24 and 48 hours (n = 139).

RESULTS

Serious bacterial illness was diagnosed in 65 infants (8.7 percent). Of these 65 infants, 64 were identified by our screening criteria for inpatient care and antibiotic treatment (sensitivity = 98 percent; 95 percent confidence interval, 92 to 100). Of the 287 infants assigned to observation and no antibiotics, 286 (99.7 percent) did not have serious bacterial illness. Only two infants assigned to outpatient observation were subsequently admitted to the hospital; neither was found to have a serious illness. Outpatient care without antibiotics of the febrile infants at low risk for serious illness resulted in a savings of about $3,100 per patient.

CONCLUSIONS

With the use of strict screening criteria, a substantial number of febrile one-to-two-month-old infants can be cared for safely as outpatients and without antibiotics.

Evaluation and management of the febrile infant 60 days of age or younger

The old dogma of conservative management and hospitalization for all young febrile infants may no longer be necessary or considered the best option for many febrile infants encountered by practitioners today. All infants will continue to require individualized decisions regarding their care by astute clinicians well-versed in the best options for the management of these children. The suggestions outlined in this article are meant to be a guide for the clinician to the available options for the evaluation and management of the febrile infant 60 days of age or younger.

Practice guideline for the management of infants and children 0 to 36 months of age with fever without source. Agency for Health Care Policy and Research

STUDY OBJECTIVE

To develop guidelines for the care of infants and children from birth to 36 months of age with fever without source.

PARTICIPANTS AND SETTING

An expert panel of senior academic faculty with expertise in pediatrics and infectious diseases or emergency medicine.

DESIGN AND INTERVENTION

A comprehensive literature search was used to identify all publications pertinent to the management of the febrile child. When appropriate, meta-analysis was used to combine the results of multiple studies. One or more specific management strategies were proposed for each of the decision nodes in draft management algorithms. The draft algorithms, selected publications, and the meta-analyses were provided to the panel, which determined the final guidelines using the modified Delphi technique.

RESULTS

All toxic-appearing infants and children and all febrile infants less than 28 days of age should be hospitalized for parenteral antibiotic therapy. Febrile infants 28 to 90 days of age defined at low risk by specific clinical and laboratory criteria may be managed as outpatients if close follow-up is assured. Older children with fever less than 39.0 C without source need no laboratory tests or antibiotics. Children 3 to 36 months of age with fever of 39.0 C or more and whose WBC count is 15,000/mm3 or more should have a blood culture and be treated with antibiotics pending culture results. Urine cultures should be obtained from all boys 6 months of age or less and all girls 2 years of age or less who are treated with antibiotics.

CONCLUSION

These guidelines do not eliminate all risk or strictly confine antibiotic treatment to children likely to have occult bacteremia. Physicians may individualize therapy based on clinical circumstances or adopt a variation of these guidelines based on a different interpretation of the evidence.

What is fever? Normal temperature in infants less than 3 months old

To determine the normal temperature of healthy infants, we studied 691 infants less than 3 months of age being seen for regularly scheduled well-baby visits. All temperatures were taken rectally with an electronic thermometer. The mean temperature was 37.5 degrees C +/- 0.3 degrees C. Using a cutoff of 2 standard deviations (SD) above the mean, fever would be defined as a temperature > or = 38.1 degrees C. The 95th percentile was 38.0 degrees C, and > or = 38.1 degrees C would correspond to values above the 95th percentile. The most widely used definition of fever at present is a temperature > or = 38.0 degrees C; by this definition, 6.5% of these well infants would be considered to have a fever. A significant rise in temperature with age was noted. For infants from birth to 30 days old, 2 SD above the mean was 38.0 degrees C; for those 31 to 60 days old, it was 38.1 degrees C; and for those 61 to 91 days old, it was 38.2 degrees C. Similarly, the 95th percentile was 37.9 degrees C, 38.0 degrees C, and 38.1 degrees C, respectively. Temperature also varied significantly with the season of the year, being higher in the summer (2 SD above a mean = 38.3 degrees C) than in the winter (2 SD above a mean = 38.0 degrees C). Fever should be defined as a temperature > or = 38.0 degrees C in infants less than 30 days of age, > or = 38.1 degrees C in 1-month-olds, and > or = 38.2 degrees C in 2-month-olds.

The sepsis workup for the febrile child

The sick infant or toddler who presents with a high fever or suspected sepsis must have all possible sources for bacterial infection excluded by clinical evaluation or laboratory studies as quickly and safely as possible. The process is frightening and often painful for the child. The process can be difficult for the physician because of the smallness of anatomic structures in children and the infrequent performance of pediatric procedures by many emergency physicians. This article uses a case report to illustrate features of the sepsis workup. Methods and sites that have been used with the most frequent success are described and alternatives and pitfalls are listed.

Outpatient treatment of febrile infants 28 to 89 days of age with intramuscular administration of ceftriaxone

STUDY OBJECTIVE

To determine the outcome of outpatient treatment of febrile infants 28 to 89 days of age with intramuscular administration of ceftriaxone.

DESIGN

Prospective consecutive cohort study.

SETTING

Urban emergency department.

PATIENTS

Five hundred three infants 28 to 89 days of age with temperatures greater than or equal to 38 degrees C who did not appear ill, had no source of fever detected on physical examination, had a peripheral leukocyte count less than 20 x 10(9) cells/L, had a cerebrospinal fluid leukocyte count less than 10 x 10(6)/L, did not have measurable urinary leukocyte esterase, and had a caretaker available by telephone. Follow-up was obtained for all but one patient (99.8%).

INTERVENTION

After blood, urine, and cerebrospinal fluid cultures had been obtained, the infants received 50 mg/kg intramuscularly administered ceftriaxone and were discharged home. The infants returned for evaluation and further intramuscular administration of ceftriaxone 24 hours later; telephone follow-up was conducted 2 and 7 days later.

RESULTS

Twenty-seven patients (5.4%) had a serious bacterial infection identified during follow-up; 476 (94.6%) did not. Of the 27 infants with serious bacterial infections, 9 (1.8%) had bacteremia (8 of these had occult bacteremia and 1 had bacteremia with a urinary tract infection), 8 (1.6%) had urinary tract infections without bacteremia, and 10 (2.0%) had bacterial gastroenteritis without bacteremia. Clinical screening criteria did not enable discrimination between infants with and those without serious bacterial infections. All infants with serious bacterial infections received an appropriate course of antimicrobial therapy and were well at follow-up. One infant had osteomyelitis diagnosed 1 week after entry into the study, received an appropriate course of intravenous antimicrobial therapy, and recovered fully.

CONCLUSIONS

After a full evaluation for sepsis, outpatient treatment of febrile infants with intramuscular administration of ceftriaxone pending culture results and adherence to a strict follow-up protocol is a successful alternative to hospital admission.

Febrile infants less than eight weeks old. Predictors of infection

Febrile infants less than eight weeks old frequently are admitted and receive parenteral antibiotics for treatment of possible sepsis. The authors assess 52 infants less than eight weeks old with a rectal temperature of 38.1 degrees C or higher as having either a readily identifiable focus of infection by physical examination, appearing "toxic" without a focus, or appearing well. The authors screened patients by using white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and chest radiographs in addition to blood, cerebrospinal fluid and urine cultures. The authors found a 9.6% incidence of bacteria in the 52 infants evaluated, with a 4.3% incidence in those febrile infants who appeared well. Five patients had positive blood cultures with Group B B Hemolytic streptococcus (four patients), and Viridans streptococcus (one patient). A clinical assessment of toxicity and a total band count greater than or equal to 0.5 x 10(3) cells/uL together were sensitive indicators of bacteremia, as were toxicity and a positive CRP. A "toxic" appearance, a WBC count greater than or equal to 15 x 10(3) cells/uL and an ESR greater than 30 were specific indicators of bacteria. Based on these data, identification of bacteremia in febrile infants may be possible with clinical assessment and screening laboratory tests. Because of the relatively small sampling size of this study, the authors feel that evaluation of a larger number of patients is warranted to evaluate these sensitivities in a more diffuse patient population.

Epidemiology and laboratory diagnosis of infection with viral and bacterial pathogens in infants hospitalized for suspected sepsis

A prospective study was conducted to determine the frequency and distribution of bacterial and viral pathogens in infants hospitalized with suspected sepsis and to evaluate the potential of virus detection for improving patient management. A causative organism was detected in 157 (67%) of 233 previously healthy infants less than 3 months of age, who had been hospitalized for suspected sepsis: 19 (8%) had bacterial infections, 135 (58%) had viral infections, and 3 (1%) had mixed viral-bacterial infections. Viral infections occurred in a seasonal pattern: enteroviruses were responsible for most of the hospitalizations during summer and fall (65/110; 63%) and respiratory syncytial and influenza A viruses were responsible for most of the infections during winter (44/81; 55%). In contrast, bacterial infections were not seasonally distributed. Virus was detected in 33% of the 138 infected infants within 24 hours, and in 64% within 3 days. We conclude that viral infections are prevalent among infants hospitalized for suspected sepsis, and most can be detected early enough to influence patient management.

Ambulatory care of febrile infants younger than 2 months of age classified as being at low risk for having serious bacterial infections

We prospectively examined whether febrile infants younger than 2 months of age who were defined as being at low risk for having bacterial infection could be observed as outpatients without the usual complete evaluation for sepsis and without antibiotic treatment. A total of 237 previously healthy febrile infants were seen at the Pediatric Emergency Room over 17 1/2 months. One hundred forty-eight infants (63%) fulfilled the criteria for being at low risk: no physical findings consisting of soft tissue or skeletal infections, no purulent otitis media, normal urinalysis, less than 25 white blood cells per high-power field on microsopic stool examination, peripheral leukocyte count 5000 to 15,000/mm3 with less than 1500 band cells/mm3. One infant appeared too ill to be included, and had sepsis and meningitis. None of the 148 infants at low risk had bacterial infections, versus 21 of 88 (24%) of those at high risk (P less than 0.0001); eight of 88 (9%) had bacteremia. Of the 148 infants classified as being at low risk for having bacterial infection, 62 (42%) were discharged to home, and 72 (49%) were initially observed for less than or equal to 24 hours and then discharged. Seventeen infants (11%) were hospitalized: in six, low risk became high risk; six had indications other than fever; and five because the study physicians could not be found. The 137 nontreated infants were closely observed as outpatients. The duration of fever was less than 48 hours in 42%, and less than 96 hours in 91%. All infants were observed for at least 10 days after the last examination. The fever resolved spontaneously in all infants but two, with otitis media, who were treated as outpatients. Our data suggest that management of fever in selected young infants as outpatients is feasible if meticulous follow-up is provided.

Weight loss and body temperature changes in breast-fed and bottle-fed neonates

Among 1138 newborns in a Level II nursery, breast-fed and formula-fed infants were comparable in terms of sex, mode of delivery, gestational age, birth weight, and birth temperature. Breast-fed neonates subsequently lost more weight and a greater percentage of their birth weight (mean, 7.4% vs. 4.9%) than did formula-fed infants. Loss of more than 10 percent of birth weight was associated with short gestation and low birth weight and with breast feeding. Birth weight loss of greater than or equal to 3 percent was associated with a risk of fever (greater than or equal to 37.5 degrees C) among breast-fed and formula-fed infants, but there was no gradient of increasing risk of fever with increasing percentage weight loss beyond 3 percent. After weight loss and other significant variables were adjusted for in a multivariate analysis, breast feeding was not independently predictive of fever. Although breast feeding may be associated with weight loss, it is not prudent to assume that this is the cause of fever in a breast-fed neonate.

Identification of infants unlikely to have serious bacterial infection although hospitalized for suspected sepsis

During a 2-year period, 233 infants younger than 3 months were prospectively studied to determine whether physical examination, white blood cell and band count, and urinalysis could identify infants unlikely to have serious bacterial infections. Only previously healthy infants (born at term, no perinatal complications, no previous or underlying diseases, no previous antibiotic therapy) were studied. One hundred forty-four (62%) of the 233 infants were considered unlikely to have serious bacterial infections, because they did not have physical findings consistent with ear, soft tissue, or skeletal infection, had between 5000 and 15,000 white blood cells/mm3, had less than 1500 bands/mm3, and urinalysis yielded normal findings. Eighty-nine (38%) infants did not meet one or more of these criteria and were classified as being at high risk for serious bacterial infection. Only one (0.7%) of the 144 infants in the low-risk group had a serious infection, compared with 22 (25%) of the 89 infants in the high risk group (P less than 0.0001). None of the infants in the low-risk group had bacteremia, compared with nine (10%) of the 89 infants in the high-risk group (P less than 0.0005). Neither traditional risk factors, such as age, sex, and temperature, nor other signs, symptoms, or laboratory findings were adequate predictors of serious bacterial infection. We conclude that previously healthy infants younger than 3 months with an acute illness are unlikely to have serious bacterial infection if they have no findings consistent with ear, soft tissue, or skeletal infections and have normal white blood cell and band form counts and normal urine findings.

Variability in the management of the febrile infant under 2 months of age

The management in the emergency department of febrile infants less than 2 months of age is influenced by the standard of practice in the community. We sought to determine if uniform practices existed across the United States. Individual academically based faculty from 154 (61%) United States pediatric residency programs responding to a questionnaire on the emergency department management of febrile infants less than 2 months of age showed great variability. Twenty-nine respondents reported written policies and 103 reported informal but defined guidelines for the evaluation and management of infants seen at their institutions. There was little consensus among the respondents as to the definition of fever in this age group. Those at institutions with formal policies reported using more laboratory tests in the evaluation. Respondents differed on the number and types of tests used and on antibiotic administration. University affiliation, type of population served, or presence of advanced training programs in ambulatory pediatrics were not related to the type of policy. The care of the young febrile infant varies greatly.

Evaluation of the febrile child under 2 years of age

Unlike older children and adults, fever in young children may reflect serious underlying disease despite the lack of associated findings on physical examination. Laboratory examinations may provide important information in the management of these children. The recent literature suggests a systematic approach to the evaluation and management of the young febrile child.