Febrile Child Ping-Wei Chen PGY-1 Emergency Medicine Dr. Lorraine Mabon

Objectives Definition of Fever Measuring Fever Approach to Managing Febrile Patient – <30 days old – 1-3 months old – >3 months old

What is a fever? Pathophysiology – Increased hypothalamic set point Pyrogens – Exogenous (eg: Gram Neg. LPS) – Endogenous (eg: IL-1, IL-6, TNF) Prostaglandin E-2 – Central effects – Peripheral effects

No, seriously, what is a fever? Various definitions – Wunderlich 1868 Das Verhalten der Eigenwdrlne in Krankheilen 25,000 patients: several million measurements Axillary measurements Fever >38C Landmark Studies – Fever ≥ 38.0C

Temperature Measurement Variations in temperature – diurnal, age, gender, prandial state Axillary < Oral < Rectal

Here at Home

275 subjects – 5 temperature measurements 4 temple (nurse x 2, parent x 2), 1 rectal Results good correlation (r=0.68) “fair” agreement; 95% CI difference: -1.0C to +1.5C

Case 1 25 day old female – Mother thought “baby feels warm”, measured rectal temp: 38.3C Otherwise, no concerns. What else do you want to know on history?

History Length/Duration of Illness Antipyretic use Birth History (maternal fever, GBS, PROM, STIs) Medical History (immunocompetency) Immunization status Sick contacts Behaviour/Localizing symptoms – eg: HNT, Resp, GI, GU

Case 1 On Exam – 38.4C, 132bpm, RR26, 100% Room Air – Otherwise examines well. No focus of infection identified. What do you want to do with this patient?

<30 days old Rate of serious bacterial illness – Approximately 9% to 12% Immature Immune systems -decreased opsonin activity -impaired neutrophil chemotaxis -decreased macrophage function Unimmunized Status Limited sick behaviours

Infants between 1 and 28 days old with a fever should be presumed to have a serious bacterial infection. (Level A Recommendation)

<30 days old Admit Full Septic Workup – CBC with differential – Blood Culture – Urine dip, R+M – Urine Culture – LP IV Antibiotics – Ampicillin/Cefotaxime – ?Acyclovir Chest Xray – Only if 1 of: RR>50, Coryza, Cough, Nasal flaring,Grunting, Stridor, Rales, Rhonchi, Wheezing, ?WBC>20 Stool Culture – If diarrhea or >5WBC/Hpf

Bugs Commonly: – Group B Streptococcus – Listeria Monocytogenes – E. Coli – Enterococcus Less Commonly: – S. pneumoniae, H. influenzae, N. meningitidis Rarely: – S. aureus, Salmonella

Case 2 62 day old male – Mother concerned about possible increased lethargy for 1 day – Rectal temperature 38.6C – Review of systems otherwise negative – Healthy, Immunizations UTD, normal pregnancy P/E: -Vitals: 38.7C, 133bpm, RR24, 100% Room Air -otherwise examines well (no focus of infection)

Management Strategies

Rochester Criteria Management – Option 1: Admission Observation No Abx – Option 2: Full Septic Workup Single Dose IM Ceftriaxone F/U 24 hours – Only if reliable parents! 233 infants Low Risk Criteria -appear well -previously healthy -WBC Bands <1.5 -Urine <10 WBC/Hpf -Stool <5 WBC/Hpf (if diarrhea) -NOTE: No LP criteria! NPV = 98.9%

Philadelphia Criteria 747 patients Low Risk Criteria – WBC <15 – Urine WBC <10/Hpf – Benign urine on R+M – CSF WBC <8/mm3 – CSF Negative Gram Stain – Negative CXRay NPV = 98% Management – Full septic workup – Outpatient – No antibiotics

Philadelphia Results

Boston Criteria 503 patients Low Risk Criteria – Not ill appearing – No ear, soft tissue, joint, bone infection identified – WBC <20 – CSF WBC <10 – Urine neg. leukocytes NPV = 95% Management – Full septic workup – Outpatient therapy – IM ceftriaxone

Pittsburgh Criteria 404 patients Low Risk Criteria – Well appearance – Not premature, No Abx, Not ill – WBC >5 and <15 – Bands <1500/mm3 – CSF WBC <5 – Urine WBC <9/mm3 – Urine negative Gram stain – Stool WBC <5 (if done) – Negative CXRay (if done) NPV = 100% Management – Full septic workup – Admission – Observation – No Abx

1-3 month old High Risk Management – Full Septic Workup – Admission – Empiric Antibiotics Cefotaxime Ceftriaxone “Low Risk” Management – Guided by your study of choice

Case 3 2 year old male – 2 days of increased lethargy, decreased appetite – Rectal temperature 38.7C P/E: Vitals 38.7C, 125bpm, RR24, 99% Room Air -examines and appears well (no focus of infection) - Healthy - Immunizations UTD - Review of Systems negative

Alberta’s Routine Immunization Schedule Two months DTaP-IPV-Hib1 Pneumococcal conjugate Meningococcal conjugate Four months DTaP-IPV-Hib Pneumococcal conjugate Meningococcal conjugate Six months DTaP-IPV-Hib Pneumococcal conjugate Meningococcal conjugate

Prevnar Vaccine (PCV7) Covers Serotypes 4,6B,9V,14,18C,19F,23F Polysaccharide conjugated to protein Introduced in Calgary July 2002

>3 months old

Urine Studies Clinical decision rule to identify febrile young girls at risk of urinary tract infection Gorelick MH et al. Arch Pediatr Adoles Med 2000;154(4): females <2 year of age with UTI 2 of 5: -Less than 12 months old -White race -Temperature of 39.0°C or higher -Fever for 2 days or more -Absence of another source of fever on examination Sensitivity: 95% Specificity: 31%

What about boys? No Clinical Decision Rule Urine Cultures – All boys <6 months – Uncircumcised boys <12 months

Chest Radiography Level B Recommendation: A chest radiograph should be obtained in febrile children aged younger than 3 months with evidence of acute respiratory illness. Level C Recommendation: Consider a chest radiograph in children older than 3 months with a temperature >39.0C and a WBC count greater than 20.

Questions?

Summary Sick? – Full Septic Workup/Admission/Empiric Abx <30 days old – Full Septic Workup/Admission/Empiric Abx 1 to 3 months old – Let the landmark studies guide you >3 months – Let the immunization status guide you