as a single generalized tonic-clonic seizure that lasts

< 1 5 minutes in children aged 6 months to 6 years with no

resulting focal neurologic deficits. These seizures occur in

the setting of fever in previously healthy children with no

history of epilepsy or signs of central nervous system ( CNS)

infection. Three percent to 5% of all children will have a

simple febrile seizure. A source should be investigated for

a patient presenting with a simple febrile seizure, but an

extensive work-up is usually not indicated. A febrile

seizure is considered complex if it has focal features, lasts

longer than 15 minutes, or occurs more than once in

24 hours. A more extensive work-up including laboratory

studies, imaging, and lumbar puncture should be strongly

considered in those presenting with complex febrile

seizures.

..... Physical Examination

Vital signs and general appearance should always be e valuated before proceeding with the remainder of the physical

exam. Heart rate can be elevated approximately 10 bpm for

every 1 °C of elevation in temperature. However, tachycardia

out of proportion to fever can indicate sepsis. Children and

infants with sepsis differ from adults as they often do not

demonstrate hypotension until very late in the course due

to a compensatory increase in cardiac output. Thus a normal blood pressure is not necessarily reassuring.

Tachycardia and poor peripheral perfusion occur before

hypotension and can be early signs of impending

circulatory collapse.

Evaluating the general appearance of an infant or child

with fever is also crucial. Infants or children who are

lethargic or demonstrate paradoxical irritability ( eg,

inconsolable when held by parents) may have a CNS

infection. A head-to-toe physical exam should be

performed. Special attention should be paid to the anterior fontanelle in infants; a bulging tense fontanelle may

indicate meningitis, whereas a sunken fontanelle may

indicate severe dehydration. In older children, assessment

of neck pain, stiffness, and range of motion may also

be useful in helping establish a diagnosis of CNS infection.

Evaluate the lung fields for crackles, asymmetry, and work

of breathing. Forced expiration and percussion may assist

in the detection of areas of consolidation. Carefully

examine the skin to identify any rashes, petechiae, or

purpura. Meningococcemia should be assumed in

a febrile, ill-appearing child with a petechial or purpuric

rash until proven otherwise. Additionally, jaundice in a

neonate may indicate the presence of sepsis but is not a

specific finding. The extremities should be examined

closely for erythema, swelling, warmth, focal tenderness,

and decreased range of motion, as this may indicate

osteomyelitis, pyomyositis, or septic arthritis. These

infections are more common in children than in adults. A

reassuring clinical examination in infants <3 months does

not necessarily rule out an SBI and should not be used in

isolation to guide management in this age group.

DIAGNOSTIC STUDIES

..... Laboratory

Laboratory tests to consider include a complete blood

count, urinalysis, urine culture, blood culture, and cerebrospinal fluid (CSF) studies. The appropriate tests to

order, if any, depend on the history and physical examination, clinical appearance, age, and risk factors for SBI.

..... Imaging

A chest x-ray (CXR) may be helpful in identifying pulmo ­

nary infection in patients with tachypnea, cough, hypoxia,

or other signs of lower respiratory tract disease. Signs of

osteomyelitis may not be apparent on plain radiographs

until the infection has been present for at least 7-10 days.

Additional imaging, including computed tomography for

intra-abdominal infection, may be helpful depending on

the patient's specific signs and symptoms.

MEDICAL DECISION MAKING

The differential diagnosis for acute fever in an infant or

child is broad and includes minor illnesses, such as viral

infections, upper respiratory infections, and otitis media,

to more significant illnesses, including pneumonia, pyelo ­

nephritis,