The Pediatric Emergency Care Applied Research Network (PECARN) rule for febrile infants is a clinical calculator used in the pediatric population, specifically for infants aged 60 days or younger who present with fever. The PECARN rule helps clinicians stratify the risk of serious bacterial infections (SBIs) such as meningitis, bacteremia, and urinary tract infections in febrile infants. It uses a combination of patient history, physical examination, and laboratory findings to determine the risk level. 

The clinical utility of the PECARN rule is to guide decision-making regarding the need for lumbar puncture, hospitalization, and antibiotic treatment in febrile infants. It helps to avoid unnecessary invasive procedures and hospitalizations, thus reducing healthcare costs and potential complications.

The PECARN rule should not be used in infants with obvious source of fever (like otitis media or bronchiolitis), those with a known underlying serious disease (like congenital heart disease or immunodeficiency), or in infants who look seriously ill. It is also not applicable to infants who have been previously treated with antibiotics for the current febrile episode.

Pediatric Emergency Care Applied Research Network rule for febrile infants (PECARN rule)

# Criteria
 ## Urinalysis positive
A. Yes
B. No
## ANC > 4,090/mcL
C. Yes
D. No
## Serum procalcitonin > 1.71 ng/mL
E. Yes
F. No

# Conditions
- B and D and F
- true