pediatrics
Fever in Infants and Children
Evaluation of Fever in Infants and Children
History of present illnessshould note degree and duration of fever, method of measurement, and the dose and frequency of antipyretics (if any). Important associated symptoms that suggest serious illness include poor appetite, irritability, lethargy, and change in crying (eg, duration, character). Associated symptoms that may suggest the cause include vomiting, diarrhea (including presence of blood or mucus), cough, difficulty breathing, favoring of an extremity or joint, and strong or foul-smelling urine. Drug history should be reviewed for indications of drug-induced fever. Factors that predispose to infection are identified. In neonates, these factors include prematurity, prolonged rupture of membranes, maternal fever, and positive prenatal tests (usually for group B streptococcal infections, cytomegalovirus infections, or sexually transmitted diseases). For all children, predisposing factors include recent exposures to infection (including family, caregiver, and school or daycare infection), indwelling medical devices (eg, catheters, ventriculoperitoneal shunts), recent surgery, travel and environmental exposures (eg, to endemic areas, to ticks, mosquitoes, cats, farm animals, or reptiles), and known or suspected immune deficiencies. Review of systemsshould note symptoms suggesting possible causes, including runny nose and congestion (viral upper respiratory infection), headache (sinusitis, Lyme disease, meningitis), ear pain or waking in the night with signs of discomfort (otitis media), cough or wheezing (pneumonia, bronchiolitis), abdominal pain (pneumonia, strep pharyngitis, gastroenteritis, urinary tract infection, abdominal abscess), back pain (pyelonephritis), and any history of joint swelling or redness (Lyme disease, osteomyelitis). A history of repeated infections (immunodeficiency) or symptoms that suggest a chronic illness, such as poor weight gain or weight loss (tuberculosis, cancer), is identified. Certain symptoms can help direct the evaluation toward noninfectious causes; they include heart palpitations, sweating, and heat intolerance (hyperthyroidism) and recurrent or cyclic symptoms (a rheumatoid, inflammatory, or hereditary disorder). Past medical historyshould note previous fevers or infections and known conditions predisposing to infection (eg, congenital heart disease, sickle cell anemia, cancer, immunodeficiency). A family history of an autoimmune disorder or other hereditary conditions (eg, familial dysautonomia, familial Mediterranean fever) is sought. Vaccination history is reviewed to identify patients at risk of infections that can be prevented by a vaccine. Vital signs are reviewed, noting abnormalities in temperature and respiratory rate. In ill-appearing children, blood pressure should also be measured. Temperature should be measured rectally in infants for accuracy. Any child with cough, tachypnea, or labored breathing requires pulse oximetry. The child’s overall appearance and response to the examination are important. A febrile child who is overly compliant or listless is of more concern than one who is uncooperative. However, an irritable infant or child who is inconsolable is also of concern. The febrile child who looks quite ill, especially when the temperature has come down, is of great concern and requires in-depth evaluation and continued observation. However, children who appear more comfortable after antipyretic therapy do not always have a benign disorder. The remainder of the physical examination seeks signs of causative disorders ( see Table: Examination of the Febrile Child ). The following findings are of particular concern: Age<1 month Lethargy, listlessness, or toxic appearance Respiratory distress Petechiae or purpura Inconsolability Although serious illness does not always cause high fever and many high fevers result from self-limited viral infections, a temperature of≥39°C in children<36 months indicates higher risk of serious bacterial infection. Other vital signs also are significant. Hypotension should raise concern about hypovolemia, sepsis, or myocardial dysfunction. Tachycardia in the absence of hypotension may be caused by fever (10 to 20 beats/minute increase for each degree above normal) or hypovolemia. An increased respiratory rate may be a response to fever, indicate a pulmonary source of the illness, or be respiratory compensation for metabolic acidosis. is infectious in most cases, and, of these, most are viral. History and examination are adequate to make a diagnosis in children > 36 months who are otherwise well and not toxic-appearing. Typically, they have a viral respiratory illness (recent ill contact, runny nose, wheeze, or cough) or gastrointestinal illness (ill contact, diarrhea, and vomiting). Other findings also suggest specific causes ( see Table: Examination of the Febrile Child ). 36 months, the possibility of Occult Bacteremia and Fever Without Apparent Source in Infants and Young Children , plus the frequent absence of focal findings in neonates and young infants with serious bacterial infection, necessitates a different approach. Evaluation varies by age group. Accepted categories are neonates ( Acute recurrent or periodic fever and chronic fever ( Fever of Unknown Origin (FUO) ) Testing depends on age, appearance of the child, and whether the fever is Testing for Acute Fever or 