Pediatric Fever Emergency Medicine Clerkship Indiana University
Objectives • Review the approach to pediatric fever • Examine the work up for pediatric fever without a source (FWS) in stratified age groups • Discuss the impact of current vaccines on our approach
Fever • 20% of Pediatric Emergency Department visits • 35% of Ambulatory visits • 20% have fever without a source after H&P • “Fever Phobia”
“Fever Phobia” • Study of 340 caregivers • 56% very worried about potential harm of fever • 7% thought temp could rise >110 F if left untreated • 91% believed fever could cause harmful effects • 21% brain damage • 14% death • 46% perceived their doctors to be very concerned about fever • 14% gave acetaminophen and 44% gave ibuprofen at too frequent dosing intervals Pediatrics. 2001;107 (6): 1241-1246.
“Fever Phobia” • “Pediatric health care providers have a unique opportunity to make an impact on parental understanding of fever and its role in illness” Pediatrics. 2001;107 (6): 1241-1246.
What is the definition of fever? • Generally fever defined as at least 100.4°F • < 3 months fever is ≥100.4°F (38°C) • > 3 months still has same lower limit of 100.4°F (but diagnostic testing usually begins at 102.2°F or 39°C)
Defining Fever: How do we take the temperature? • Axillary and tympanic temps are unreliable in young children (sensitivity 50-65%) • rectal temperature is the “gold” standard • Expert panel concluded 100.4°F(38°C) by rectal thermometer should be used as the lower limit of the definition of fever
Defining Fever • Fever documented at home by similar means should be considered the same as that documented in the ED • 92% of the infants who had rectal fever at home had subsequent fever in next 48 hours. So, even if they are afebrile on presentation you can trust the rectal temperature at home. Pediatric Infect Dis J. 1990 Mar;9(3):158-60
Defining Fever • Be sure to communicate with the parents • ask how it was taken and if they added degrees • i.e. make sure 103°F was not 100.3°F
Why is fever so important? • Your Goal is to rule out Serious Bacterial Infection (SBI) • UTI • Meningitis • Septicemia • Bone and joint infections • Pneumonia • Bacterial gastroenteritis
History • Birth history? Specifically for neonates-maternal infection or fever at delivery • Eating? • Urine output? • Irritability? • Excessive sleepiness? • Immunized?
Physical • Hypo- or Hyperthermic • Vitals • Rash • Fontanel • Respiratory • Circ or no Circ?
“Sick or Not Sick?” • Allfebrile children less than 36 months [or for that matter any age] that appear toxicshould be hospitalized for evaluation and treatment of possible serious bacterial infection (SBI) • What is a “toxic” appearance? • Lethargy • Signs of poor perfusion • Hypoventilation/hyperventilation • Cyanosis
The Dilemma • What do you do with the well appearing child with fever? • What diagnostics need to be done? • Antibiotics or no antibiotics? • What is the availability and reliability of follow up? How does that affect your management?
The Dilemma • Lots of literature • No definitive rules for the treatment of pediatric fever • “Guidelines” available • Mostly opinion papers over last 15 years despite changes in epidemiology • Art versus science • each patient is different • each staff is different • workups may change during community epidemics
Pediatric Fever • Stratification into different risk groups: • Neonates: 0 to 28 days • Young infants: 29 to 90 days • Older infants and young children: 3 to 36 months
Case 1 • 3 week old white female • CC: congestion and fever. • Unremarkable PMHx/BHx. • ROS neg. • Initial temp at triage was 100.1° F. • PE is non-toxic alert infant with no abnormal findings.
Do you want additional information about the fever? • How was it taken at triage? • Were there any antipyretics given? • What was the fever at home? • fever in this case at home was 101.2°F
Infant 0 to 28 days • Risk of SBI is as high as 20% • All of these patients require: • Full sepsis workup including CBC, Blood Cx, UA, Urine Cx, CSF studies and CSF Cx • Consider CXR and stool studies • Empiric antibiotics • Admission
Antibiotics • Ampicillin and gentamicin • covers GBBS, E. coli, Listeria monocytogenes • Ampicillin specifically for Listeria and provides some synergy with gentamicin forGBBS • Ampicillin and cefotaxime • covers the < 1 month etiologic agents and also S. pneumoniae • with cefotaxime you don’t have to worry about oto/renal toxicity associated with gentamicin
Antibiotics • Ceftriaxone is not used in neonates • Why? • because it competes for bilirubin binding sites and may lead to hyperbilirubinemia
Acyclovir? • Consider acyclovir • Maternal history of Herpes (especially if primary outbreak with vaginal delivery) or any noted skin or mucosal lesions • BUT in the majority of patients with neonatal HSV, there is no maternal history of HSV. • Definitely give if ill-appearing, pleocytosis with negative gram stain, vesicles, or seizures
Case 2 • 6 week old white male • Presents to the ED with fever to 101 • PMHx/BHx unremarkable • No source of infection on the exam • Looks non-toxic
Protocols • We may not be able to determine sick vs not sick by H&P alone in this age group • Several studies have attempted to develop a protocol for infants < 90 days of age • Rochester • Philadelphia
Rochester Criteria & Philadelphia Criteria • Attempt to develop more sensitive ways to detect serious illness in febrile pediatric patients using: • History • Physical • Laboratory Evaluation
Rochester Criteria & Philadelphia Criteria • Clinical Criteria: • Previously healthy, term infant with uncomplicated nursery stay • Non-toxic clinical appearance • No focal bacterial infection on exam
Rochester Criteria & Philadelphia Criteria Lab criteria for “low risk infant” CSF: <8 WBCs/mm3 Negative Gram stain Stool (when diarrhea): <5 WBC/hpf • CBC: • WBC count 5-15,000/mm3 • <1500 bands/mm3 • Band/neutrophil ratio <0.2 • Urine: • <5 WBC/hpf • Negative gram stain of unspun urine (preferred) • Or negative urine leukocyte esterase and nitrite
Back to your patient • Labs are all negative • Normal Urine, LP, CBC • What is the disposition? • Admit or send home • Empiric Antibiotics?
Low Risk Febrile Infants 28 to 90 Days Option 1 Option 2 Partial sepsis work up: Blood and Urine NO Antibiotics Follow up in 24 hours • Full Sepsis work up: Blood, Urine, CSF • Ceftriaxone (50 mg/kg) • Follow up in 24 hours
Low Risk Febrile Infants 28 to 90 Days • Parents must be reliable • Phones • Ability to understand instructions • Close follow up must be ensured • May need to wake up the primary care physician
Non-Low Risk Febrile Infants 28 to 90 Days • In other words: Failed Rochester Criteria • Full Sepsis work up • Empiric antibiotics • Admit
Antibiotics • Ceftriaxone • covers S. pneumoniae, H. influenzae, and N. meningitidis • Add vancomycin if any concern for S. pneumoniae on LP in any age range (resistant strains have been appearing in CSF)
Special ConsiderationsCase 3 • 2 month old asian male • Fever at home to 101 • Immunizations given today at PMD clinic • PMHx/BHx negative • Well appearing
Fever after immunizations • 2.8% of infants < 12 weeks who presented to the ED with fever within 24 hours of immunizations still had a UTI. • There were not any other serious bacterial infections noted in the first 24 hours. • After the first 24 hours, rates of serious bacterial infection (including UTI) increased to 8.9%. AcadEmerg Med. 2009 Dec; 16(12):1284-9
Fever after immunization • If less than 24 hours since immunizations • Consider UA, Urine Cx • May not need further work up • If more than 24 hours since immunizations • Consider full vs partial sepsis work up
Special ConsiderationCase 4 • 2 month old hispanic female • Nasal congestion, cough • PMHx/BHx negative • Tachypneic, mild retractions and wheezing on exam • Clinical dx: Bronchiolitis
Bronchiolitis with fever • Significantly lower risk of most SBIs • However, the rate of UTI remains significant (2.4-5.4%) • 1.1% of infants with bronchiolitis had bacteremia compared to 2.3% of febrile infants without bronchiolitis Pediatrics 2004 Jun; 113(6):1728-34 Pediatrics 2009 Jul; 124(1):30-9
Bronchiolitis with fever • 0-28 days: Full sepsis work up • >29 days: UA and Urine Cx
Case 5 • 7 month old male • Fever to 103 for 2 days • PMHx/BHx negative • Immunizations are UTD • Exam is unremarkable • What is your work up?
Child 3 to 36 months with FWS: Occult Bacteremia • PCV7 (Prevnar): • Targets 7 capsular serotypes of S. pneumo that caused 80% of the infections • Licensed in US in 2000 • Studies have shown a 90% reduction in invasive disease in children receiving the vaccine
Child 3 to 36 months with FWS: Occult Bacteremia • Post Hib and PCV7 vaccines: • Causes of bacteremia have changed: • E.Coli 33% • Non-vaccine serotype S. pneumoniae 33% • S. aureus, Salmonella, N. meningitidis, S. pyogenes 33% Pediatr Infect Disease J. 2006; 25:293-300
Child 3 to 36 months with FWS: Occult Bacteremia • Post Hib and PCV7 era: • Occult bacteremia rates are now between 0-0.74%! • So…..do you really need to blood culture??
Child 3 to 36 months with FWS: Occult Bacteremia • In addition, in the post vaccine era, studies have shown that the rate of contaminated blood cultures equaled the rate of pathogenic blood cultures. • In one study, children less than 6 months old were more likely to have contaminated blood cultures than true bacteremia. Pediatric Adolescent Medicine. 1998; July; 152; 624-628
Child 3 to 36 months with FWS: Occult Bacteremia • “For countries with widespread vaccination with Hib and PCV7, the data indicates that rates of occult bacteremia and subsequent SBI are extremely rare” • So, in the non toxic appearing child, age 3-36 months with FWS. The blood culture and CBC are not a necessary part of the work up. Minerva Pediatr 2009;61: 489-501.
Child 3 to 36 months with FWS: Urinary Tract Infection • Most common SBI
Child 3 to 36 months with FWS: Urinary Tract Infection • UTI’s almost always occult < 2 years of age • Most common occult bacterial infection • UTI occur in 7% of males < 6 months and 8% of females < 12 months with fever without a source
Child 3 to 36 months with FWS: Urinary Tract Infection • Who needs a UA and Urine Cx • All females <24 mo • All males <6 mo • Uncircumcised males <12 mo
Child 3 to 36 months with FWS: UA/Urine Culture • Get cath specimens • supra-pubic or trans-urethral • clean catch impossible • bags are usually not helpful (unless retrospectively the culture is negative) • If you get urine, SEND for culture • up to 20% of negative UA’s will grow pathogen