For previously healthy children 3-36 months, a temp of 102.2F requires further evaluation. Studies have shown that axillary and tympanic temp are unreliable in young children. About 10% of children yopunger than 36 months without evident source of fever had occult bacteremia and SBI.
decrease in the number of cases of occult bacteremia and SBI in febrile children since the advent of Haemophilus influenzae type b and Streptococcus pneumoniae vaccines. Epidemiologic data also have shown a decrease in the rates of S. pneumoniae infections since the introduction of a pneumococcal conjugate vaccine.9-13 Although recommendations may change, physicians should still take a cautious approach because of the potential for adverse consequences from unrecognized and untreated SBI.
Occult bacteremia is the presence of pathogenic bacteria in the blood of a febrile child without focus of infection or signs of sepsis.
Any history of serious infection or medical problems, maternal fever at the time of delivery, or group B streptococcal vaginal colonization may put the child at a higher risk of SBI. A history of maternal herpes simplex virus (HSV) infection should prompt screening for HSV, especially in infants younger than 29 days. Obtaining an accurate history from the parent or caregiver is important; the history obtained should include the following information. Fever history : What was child's temperature prior to presentation, and how was temperature measured? Consider fever documented at home by a reliable parent or caregiver the same as fever found on presentation. (Accept parental reports of maximum temperature.)
In a study of 3,066 children younger than three months, the features most predictive of occult bacteremia and bacterial meningitis were toxic appearance, age younger than 30 days, and rectal temperature of at least 103° F (39.4° C).9
Note that using a test with this sensitivity as the sole determinant of SBI is inappropriate because it will miss more than 30 percent of patients with SBI.
Consider cerebrospinal fluid (CSF) studies and culture. (Obtain CSF if meningitis is suspected.)
Dr. Meenakshi Aggarwal PGY2 Family Medicine Emory UniversityFever Of Unknown OriginDr Meenakshi Aggarwal MDEmory University Family Medicine
Definitions• Clinically significant fever is defined as a rectal temperature of 100.4 degree F (38C) or higher.• FUO or FWLS: An acute febrile illness in which etiology of the fever is not apparent after a thorough H&P.
Why the “Fever Phobia”?• Could be a sign of serious infection• Younger children at higher risk• Absence of other s/s make diagnosis difficult• Antibiotic resistanceChallenge: To identify those kids who have fever due to a serious illness
Incidence• One in five acutely ill, non toxic appearing children have an unidentifiable source of fever.• Although most of the children have self limiting viral illness, about 1.6-1.8% kids < 36 months have occult bacteremia and serious bacterial infections (SBI)
FUO- Myths Uncovered• Physiologic response of body to infection• Usually benign illness• Serious bacterial infection-SBI and occult bacteremia is rare due to effective immunizations. Common occult SBI - UTI, meningitis, pneumonia• Symptom, not a disease. Occult bacteremia is the presence of pathogenic bacteria in the blood of a febrile child without focus of infection or signs of sepsis.
Changing Approach to FWLS• 1990’s (H flu common organism with high risk of complications) < 3 mnths: screening labs, admission, empiric abx started 3-36 mnths: temp >39C: CBC, UA. Abx if WBC>15,000 -Contd…
• Early 2000’s (H flu gone, pneumococcus etiology of OB common) < 3mnths: Work up and therapy less with increasing age. 3-36 mnths: temp >= 39.5 <18mnths- CBC, bld cx, UA and UCx. Abx for WBC >20,000 (ceftriaxone 50mg/kg) >= 18mnths - Bld Cx only
Surprise!• Pneumococcal vaccine introduced(7- valent conjugate vaccine licensed in 2000). Given at 2,4 and 6 months. Decrease in rates of S.pneumo: < 5yrs : Dec by 59% <2yrs : dec by 69% 24-35 mnths: dec by 44%
Current Approach• Any infant younger than 29 days and any child that appears toxic should undergo complete sepsis workup and get admitted for observation until culture results are obtained or the source of the fever is found and treated.
Prerequisites for FWLS• Temp >=38 degree C• Well appearing• No obvious focal infection• Previously healthy (including birth history)• Not on Antibiotics
Systemic approach to a febrile child• Age• General appearance• Past medical history• Source of fever
Evaluation• A) Thorough history: Vaccinations Sick contacts Recent symptoms Birth history Maternal history (GBS, herpes)
The Yale Observation ScaleI. Indications: a) Assessment of febrile child ages 3-36 months b) Predicts serious infection (Occult Bacteremia) c) Quantifies "Toxic Appearance" in childrenII. Scoring: A) Quality of cry - strong, sob or weak B) Reaction to parents – brief cry, intermittent cry, persistent cry. C) State Variation: Awakens quickly, difficult to awaken, no arousal D) Color: Pink, acrocyanosis, pale or cyanotic E) Hydration: moist mucous membranes, slightly dry, dry F) Social response: alert, brief smile, no smile
Interpretationd) Score 10; incidence of serious illness is 2.7%f) Score 11-15; incidence is 26%c) Score > 16; incidence of serious illness is 92.3%
Sepsis EvaluationA) WBC’s and differential:a) Low risk - Count less than 15,000/mm and bandemia <1500/mmb) Count >15,000/mm and ANC> 10,000/mm predictive of SBI (sensitivity 69% and specificity 79%)
Urine Analysisa) UTI common in febrile females and uncircumcised malesb) Always obtain a culturec) Urethral catheterization is preferred method to obtain a specimen
Lumbar Puncture: Cell count Gram stain Gluc/prtn CxStool studies: Consider obtaining a stool culture to measure fecal WBCs and stool guaiac for diarrhea.
Chest X-RayA) Chest radiography is indicated when the patient has tachypnea, retractions, focal auscultatory findings, or oxygen saturation level (SO2) on room air of less than 95%.B) Chest radiographs should also be considered if WBC is >20,000 and rectal temp > 102.2 degree F.
Recommended Management Strategies• Treatment approach for each age group of patients presented here is consistent with guidelines from the American College of Emergency Physicians and Cincinnati Children’s Hospital.
Febrile Neonates (0-28 days)• Highest risk group• Admission required• Complete sepsis workup (CBC, cath UA and UCx, bld cx, CSF studies)• HSV PCR needs to be considered if herpes suspected• IV antibiotics (ampi and cefotaxime)• Observe for 48 hrs or until source found
Neonates (29-90 days)Two management options:Option One:a) CBC, bld Cx, CSF, UA and Ucxb) If WBC’s < 15,000 and ANC < 10,000, then give ceftriaxone 50mg/kg IM and follow up in 24 hrsc) Evaluate results of bld Cx,UCx, CSF and re- examine the child.
• Option Two:c) CBC, UA and Ucx. No bld Cx, CSFd) No abxe) Parents carefully observe the child at home and re-examination within 24 hrs.f) If laboratory tests are positive, appropriate action needs to be taken.
Age ( 3-36 months)• Many febrile children do not need testing• Selective testing based on temp >39 C• Selective testing based on WBC’s• Majority have received 3 doses of Prevnar• LP is rarely needed• UTI is most common occult bacteremia.
Age 3-36 months. Cont’d• Rectal temp < 102.2 degree F: No tests, no abx, follow up if symptoms lasts longer than 48 hrs or worsens.• Rectal temp > 102.2 degree F: No abx, no testing OR CBC with diff and UA, Ucx. If WBC > 15,000 or ANC > 10,000 then obtain bld cx. Reevaluate in 24-48 hrs and consider ceftriaxone 50mg/kg IM. CSF should be done before Abx. No CSF needed if no abx given.
Evaluation Summary• For children who appear ill, conduct a complete evaluation to identify occult sources of infection. Follow the evaluation with empiric antibiotic treatment and admit the patient to a hospital for further monitoring and treatment pending culture results.• Patients aged 2-36 months may not require admission if they meet the following criteria:• Patient was healthy prior to onset of fever.• Patient has no significant risk factors.• Patient appears nontoxic and otherwise healthy.• Patients laboratory results are within reference ranges defined as low risk.
Treatment• Treatment recommendations for children with fever of unknown etiology are based upon the childs appearance, age, and temperature.• For children who do not appear toxic, treatment recommendations are as follows: – Consider no antibiotics; however, if ANC is greater than 10,000, administer ceftriaxone (50 mg/kg/dose). – Schedule a follow-up appointment within 24-48 hours and instruct parents to return with the child sooner if the condition worsens. – Hospital admission is indicated for children whose conditions worsen or whose evaluation findings suggest a serious infection
Treatment Cont’d• For children who appear toxic, treatment recommendations are as follows: – Admit child for further treatment; pending culture results, administer parenteral antibiotics. – Initially administer ceftriaxone, cefotaxime, or ampicillin/sulbactam (50 mg/kg/dose).
Medical/Legal Pitfalls• The biggest pitfall is not considering the possibility that a febrile infant has a potentially life-threatening illness.• If not treated promptly, a small percent of febrile infants who have no obvious source of serious bacterial infection may suffer serious sequelae or death.• Physicians who approach their patients as if this is a possibility and who provide appropriate evaluation and treatment are doing their best to avoid a poor outcome.• Stress to parents and caregivers the importance of follow-up care after patients are discharged.• Also stress that an infant whose symptoms worsen should be evaluated prior to the scheduled follow-up appointment or taken to the nearest emergency department for treatment.