FEBRILE INFANT CHECKLIST

INVESTIGATION OF FEVER WITHOUT SOURCE

 

 

Definitions

Investigations

Principles of Investigation

Algorithm for Investigation

References

About This Document

 

Definitions:

Fever 

·        Under age 3 yr. >38º C

·        3 mo. – 3 yr. seldom investigated <39º C

·        3 mo. to 3 yr. >39º C

·        Always rectal temperature under age 3 yr.

Bacteremia

·        Bacteria in blood with no signs or symptoms of sepsis

·        Can lead to serious bacterial infection (SBI) such as meningitis, sepsis, osteomyelitis, pyelonephritis, pneumonia or septicemia.

Source

·        Origin of infection not found in 25% of febrile infants and children.

 

Investigations:

Temperature

·        High fever carries no inherent risk by itself.

·        Risk of SBI increases with increasing temperature.

White blood cell count (WBC)

·        Liklihood ratios for SBI:  

3.9 for <5,000

2.0 for >5,000 - 20,000

3.5 for >20,000

·        55% of SBI in 5,000 - 20,000 range

Chest X-ray (CXR) to be considered if:

1.      Respiratory rate > 50

2.      Cough, wheeze, retraction, rales

3.      WBC > 20,000

·        Any 1 of the above yields 33% positive CXR.

·        None of the above yields < 1% positive CXR.

Lumbar Puncture

·        Indicated on clinical grounds or if full septic workup indicated.

·        Absence of WBC’s does not exclude meningitis.

Urinalysis and Culture

·        Bagged specimen only useful if negative.  Otherwise use clean catch, catheter or suprapubic specimen.

·        10% of infants with fever have UTI

·        Increased liklihood UTI in girls < 2yr and in uncircumcised males.

·        Significant factors include:

Temp > 39º C

Fever > 2 days

Caucasian

< 1 year of age

No apparent source of fever otherwise

·        2 or more risk factors 95% sensitive and 30% specific for UTI.

 

Principles of Investigation:

·        These are all guidelines based mainly on opinion rather that firm data.  None are endorsed by any particular group.

·        Investigation depends on age of child.

1.      0 – 28 days – neonates

·        Chance of SBI is 12% - relatively high risk.

·        If temp >38º C, do full septic workup and hospitalize.  Consider empiric parenteral antibiotics.

2.      29 days – 3 months – younger infants

·        Chance of SBI of 6-9% - somewhat less risk

·        Rochester criteria include healthy appearance, full term, no previous antibiotics, no focus on examination, WBC 5,000-15,000, urine < 10 WBC/hpf, fecal leucocytes < 5/hpf if diarrhoea.

·        If any criteria are not met, admit and do septic workup.  Consider empirical parenteral antibiotics.

·        If all criteria met consider followup at home (perhaps after negative LP) after single IM dose of Ceftriaxone 50 mg/kg.

3.      3 months – 3 years – older infants and young children.

·        Chance of SBI 1.5 – 2%.  0.3% will have serious infective sequellae and 0.03% will have meningitis.

·        If non-toxic and temperature <39º C, no investigation or antibiotic. 

·        If temperature > 39º C, do urinalysis and culture on all females < 24 mo, all uncircumcised males under 12 mo., and all circumcised males < 6 mo.

·        If age < 6 months or have not had 3 doses each of Hib and PCV7 vaccine, do urine and culture, CBC, blood culture.  CXR if WBC >20,000.  Antibiotic if WBC > 15000.

·        If age > 6 months and have had 3 doses each of Hib and PCV7 vaccine, do urine and culture only – no routine blood work.

 

 

Algorithm for investigation of fever

 

 

References:

 

1.      Baraff LJ.  Practice Guideline for the Management of Infants and Children 0 to 36 Months of Age with Fever Without Source. Ann Emerg Med. July 1993;22:108-115

2.      Baraff LJ. Management of fever without source in infants and children. Ann Emerg Med. December 2000;36:602-614.

3.      Hoberman A.  Wald, Ellen R. Reynolds Ellen A.  Penchansky L. Charron M. Update on the management of the febrile infant. Pediatric Infectious Disease Journal. 15(4):304-309, April 1996.

4.      Marvin B. Harper. Update on the management of the febrile infant Clinical Pediatric Emergency Medicine Volume 5 • Number 1 • March 2004

5.      ACEP Clinical Policies Committee Clinical Policies Subcommittee on Pediatric Fever Clinical Policy for Children Younger Than Three Years Presenting to the Emergency Department With Fever.  Annals of Emergency Medicine Volume 42 • Number 4 • October 2003

6.      Nigrovic Lise E. ,  Malley Richard.  Evaluation of the febrile child 3 to 36 months old in the era of pneumococcal conjugate vaccine: focus on occult bacteremia.  Clinical Pediatric Emergency Medicine Volume 5 • Number 1 • March 2004