SELECTED PEDIATRIC EMERGENCIES, PART 2
From Topics in Emergency Medicine, presented October 24-27, 2005, by the University of California, San
Francisco, School of Medicine, Department of Medicine, Division of Emergency Medicine
Andrea Marmor, MD, Assistant Clinical Professor, Department of Pediatrics, University of California, San
Francisco, School of Medicine
How and When Should Urine be Collected to Test for Urinary Tract Infection (UTI)?
| Background: pyelonephritis most common occult bacterial infection in children <2 yr of age who have fever without
source (FWS); UTI or pyelonephritis may be associated with urinary tract abnormality (eg, obstruction, vesicoureteral reflux
[VUR])
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| Prevalence of UTI: infants <3 mo of age with FWS—at high risk for UTI (regardless of age, gender, or circumcision
status); rate ≈10% (in some studies, 19% of uncircumcised boys and 13% of girls); febrile UTI often accompanied by bacteremia;
infants 3 mo to 2 yr of age with FWS—in girls, prevalence of UTI 5% to 10%; in boys, circumcision most important
risk factor; young uncircumcised boys at higher risk than girls; after 3 mo of age, overall risk among boys less than in
girls; overall prevalence of UTI low among febrile, circumcised males (<1%); in uncircumcised boys, 5 to 20 times higher;
incidence significantly higher in boys, but drops off rapidly after 3 mo of age; in girls, prevalence constant through first 2 yr
of life; probability of UTI—increases with duration and severity of fever and other signs of systemic illness, and lack of
other source of fever
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 | Urinalysis (UA) in infants: leukocyte esterase (LE)—most sensitive single test (sensitivity 80% to 90%); specificity
75% to 85%; nitrates—specificity 90% to 100%; sensitivity range wide but lower; blood and protein—alone, insufficient
as screen for UTI; predictive value—sensitivity and specificity same regardless of age, but predictive value
different in young infants; if prior probability of disease low (5%), positive predictive value of LE 20%; negative predictive
value good (risk for UTI <1%); if prior probability high, positive predictive value of LE increases (negative
predictive value decreases)
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| Impact on management: low-risk infant—risk for UTI ≤5%, based on age, circumcision, and clinical factors; UA has
good negative predictive value (positive predictive value less helpful); high-risk infant—positive predictive value
good (treat empirically if prior probability high); negative UA does not rule out UTI in high-risk infant
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| Obtaining specimen: catheter specimen—accurate; gold standard for UA and culture of urine in infants; invasive; bag
specimen—helpful in selected patients; no studies directly compare predictive value of UA by bag specimen to catheter
specimens; slightly more false positives with bag specimen; culture—bag specimen positive if >100,000 of single
organism present; risk for false positive or negative almost identical using high threshold for positivity; prior
probability—in high-risk infant, use catheter (with bag, risk for false negative too great); in low-risk infant, negative
predictive value of bag specimen sufficient to rule out disease (sensitivity good and similar to LE from catheter UA)
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| Recommendations: pyelonephritis presumptive diagnosis in infants and children <2 yr of age with FWS; stratify risk
based on gender and circumcision status; test for UTI when prior probability ≥5% to 10% (includes all infants <3 mo of
age with FWS); infants 3 to 24 mo of age—test all girls; consider testing uncircumcised boys <6 to 12 mo of age; in circumcised
boys, risk quite low after 3 mo of age (lower after 6 mo of age); high-risk infant—<3 mo of age or looks sick
enough to require intravenous (IV) antibiotics, or uncircumcised boy <6 mo of age; obtain catheter specimen; begin empiric
therapy if UA positive (if negative and child high-risk, consider confirmatory culture); low- to moderate-risk
infants—obtain specimen by most convenient and appropriate method; negative UA—if prior probability low, reasonable
to skip culture (risk for UTI low); if prior probability more moderate, confirm with culture (bag specimen reasonable;
catheter specimen preferred in some circumstances); positive UA (LE alone)—good positive predictive value, but
not as good as combined LE and nitrate test; confirmatory culture recommended; if prior probability moderate, consider
empiric therapy; positive UA (nitrite alone)—very specific (empiric treatment recommended); culture guides management
of nonresponders
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How Should Pyelonephritis be Managed?
| Study by Hoberman: oral therapy as effective as IV cefepime in febrile infants and young children with UTI;
speaker’s first-line drug—cephalexin (covers Escherichia coli and most other likely organisms; sensitivities local and
may change); study by Keren—7- to 14-day course superior to shorter courses in young febrile child with UTI
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| Recommendations: treat promptly; indications for IV antibiotics—toxic appearance; patient <3 mo of age or unable to
tolerate oral therapy; questionable compliance with medications or follow-up; oral therapy—preferred in well-appearing
children >3 mo of age; first-line therapy cephalexin (Keflex); consider giving first dose intramuscularly (IM) or IV (using,
eg, ceftriaxone), especially if patient very young, or observe oral administration in clinic; recommended duration 10 to 14
days; follow-up—if no response to medication within 48 hr; increase surveillance of febrile illnesses (prompt diagnosis and
treatment of recurrent UTI important to prevent long-term damage)
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| First UTI in young infant: may be sign of urinary tract abnormality; imaging recommended in high-risk patients; risk factors
for urinary tract abnormalities—young or sick-appearing infant; history of recurrent UTI; abnormal urinary
stream, blood pressure, creatinine, or growth pattern; yield for significant urinary tract pathology low after normal third
trimester ultrasonography (US); majority of VUR low-grade
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| Recommended imaging: first UTI—infant <3 mo of age, unusually sick, or fails to respond to treatment; circumcised
boys <1 yr of age (consider possibility of urinary tract abnormality); recurrent UTI—any child <2 yr of age
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| NEW RECOMMENDATIONS FOR OTITIS MEDIA
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When is Observation without Antibiotics an Option for Infants and Children with Acute Otitis Media (AOM)?
| Potential benefits of observation: avoids side effects of antibiotics and reduces bacterial resistance rate;
disadvantages—illness may persist or complications may develop in untreated infants
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| Treatment vs observation (evidence): overall, majority of children with AOM do well with or without antibiotics
(60% to 75% have resolution of symptoms within few days); in randomized trial, improvement 86% in treatment group
(70% in untreated patients); Agency for Healthcare Research and Quality (AHRQ)—12% lower clinical failure rate
with antibiotics (number needed to treat [NNT] 8); 5% to 14% of children symptomatic 1 day less (NNT 7-20); across
studies, greatest differences between antibiotic and observation groups seen in children who were younger or sicker;
complications of AOM—rates of mastoiditis low in both groups (no significant difference between groups); little evidence
that treatment prevents complications
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| Recommendations: diagnostic criteria (acute onset of symptoms; middle ear effusion; middle ear inflammation; if met,
diagnostic certainty good); provide pain and fever relief in all children; routine antibiotics for patients—<6 mo of age;
6 mo to 2 yr of age (if diagnosis certain and child severely ill); >2 yr of age (if diagnosis certain or child severely ill);
consider observation option in—infants 6 mo to 2 yr of age, if diagnosis uncertain and illness not severe; infants >2 yr
of age (diagnosis certain, but illness nonsevere or diagnosis uncertain); organisms—Streptococcus pneumoniae (most
common); Haemophilus influenzae; Moraxella catarrhalis; resistance pattern—about one third of S pneumoniae resistant
to penicillin (of those, half have high-level resistance); 50% of H influenzae β-lactamase producers (resistant to
penicillin); H influenzae most likely pathogen in patients with recurrent or persistent otitis media; 100% of M catarrhalis
β-lactamase producers (not responsive to penicillin)
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How Has Changing Microbiology of OM Affected Recommendations for Treating Recurrent or Persistent OM?
| Effect of 7-valent pneumococcal conjugate vaccine (PCV-7) on microbiology and patterns of AOM:
dramatic decrease in incidence of AOM due to S pneumoniae; overall reduction in AOM small (7%-10%); most strains in
vaccine do not cause typical OM; substantial decrease in incidence of recurrent OM; decrease in vaccine-associated strains
of S pneumoniae; slight increase in incidence of H influenzae and nonvaccine-associated S pneumoniae as causes of
OM; resistant strains of S pneumoniae in vaccine less prevalent causes of OM; minority of cases of OM affected by pneumococcal
vaccine (Prevnar)
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| Initial therapy: antibiotic choice—high-dose amoxicillin first- line (80-90 mg/kg per day; 10-day course for infants <2
yr of age with OM); minimal inhibitory concentration (MIC) effective against moderate- or intermediate-resistance
strains of S pneumoniae, and most with high-level resistance; microbiologic cure in ≈80% of OM; severe illness—
consider amoxicillin-clavulanate (90 mg/kg per day; covers broad spectrum of organisms); penicillin-allergic
patients—some cephalosporins have reasonable coverage against microbiology of OM; single-dose ceftriaxone IM
good choice in uncomplicated OM; patients with history of anaphylaxis—consider erythromycin/sulfonamide combinations;
azithromycin (however, much S pneumoniae resistance to macrolides; clarithromycin similar); persistent
OM—H influenzae most likely pathogen (majority of strains β-lactamase producers; one third have high-level resistance
to penicillin)
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| Recommendations for recurrent infection: persistence of initial organism more likely if recurrence within 7 days
(rate 40%; rate 10% in late recurrences); high-dose amoxicillin-clavulanate achieves clinical cure in majority of patients;
alternative regimens (studies)—3 doses of ceftriaxone superior to 1 dose for recurrent or persistent disease (1 dose sufficient
for uncomplicated OM); high-dose azithromycin superior to amoxicillin-clavulanate in late follow-up and had
fewer side effects; gatifloxacin superior to amoxicillin-clavulanate (no evidence of associated arthropathy; not available
for routine use in children <12 yr of age); children initially treated with amoxicillin—amoxicillin-clavulanate good
choice; consider high-dose azithromycin, 3 doses of ceftriaxone, or gatifloxacin; children initially treated with amoxicillin-clavulanate
—consider ceftriaxone IM or other options discussed
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Best Method of Hydration for Moderately Dehydrated Child
| American Academy of Pediatrics (AAP) recommends: oral hydration for children with mild-to-moderate dehydration
due to acute gastroenteritis
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| Hydration of moderately dehydrated child who is vomiting (study by Nager): children 3 to 36 mo of age;
compared IV hydration to oral or nasogastric (NG) hydration; all groups equivalent in clinical outcomes, but NG superior
in cost effectiveness and complication rate; laboratory results (electrolytes or UA) did not alter treatment or help with diagnosis;
clinical findings best to assess dehydration; study by Atherly-John—in older children, decreased time in emergency
deparment and fewer complications with NG, compared to IV
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| Managing dehydration due to gastroenteritis: minimize blood draws and IVs (unlikely to be helpful); oral or NG
hydration effective even in patients who are vomiting (shortens treatment time and reduces cost); consider NG in young
infants (more difficult to get IV in; more likely to tolerate NG tube than older child)
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Role of Adjuvant Medications or Supplements in Child with Gastroenteritis
| Pharmacologic therapy: antiemetics and antimotility agents more toxic to children than adults and cause more significant
side effects; side effects—drowsiness; dystonic reactions with prochlorperazine (Compazine); ileus with some anticholinergics;
data limited about safety and efficacy of antimotility and antiemetic agents in children; loperamide associated with increased
morbidity and mortality in infants; newer drugs—racecadotril and ondansetron effective and safe, but editorials
criticize routine use because of cost and possibility of side effects
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| Nutritional supplements: zinc—improves intestinal permeability and decreases severity of diarrhea in children
with osmotic diarrhea (studies primarily in developing countries); optimal mode of delivery and efficacy in developed
countries unknown; probiotics—associated with reduction in severity or duration of infectious and antibiotic-associated
diarrhea in children (primarily using lactobacillus); studies vary in sample size, type and dose of supplementation,
and populations studied
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| Recommendations: mainstays of therapy include oral rehydration and restoring proper nutrition as quickly as possible;
some newer drugs may be safe, but likely to add unnecessary cost and less likely to be significantly effective; educate
parents about safe use of nutritional supplements (yogurt natural source of lactobacillus); encourage return to nutritionally
appropriate diet as soon as possible (improves nutrition, gut motility and healing); never need to put breast-feeding
infant on clear fluids, and formula does not need to be diluted; avoid full-strength juices; some patients have temporary
intolerance to milk
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| MENINGITIS: ROLE OF CORTICOSTEROIDS
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| Bottom line: for S pneumoniae and H influenzae meningitis in children, corticosteroids beneficial (best when given before
or with antibiotics; no benefit if given after antibiotics); consider corticosteroids in patient with clinical diagnosis of
meningitis (initiate treatment as soon as possible); decreases inflammation and neurologic devastation associated with
meningitis
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Educational Objectives
| The goal of this program is to educate the listener about selected pediatric emergencies. After hearing and assimilating this
program, the clinician will be better able to:
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| 1. Describe how and when urine should be collected to test for urinary tract infection (UTI).
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| 2. Identify effective strategies for managing pyelonephritis.
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| 3. Decide whether observation without antibiotics is an option in a patient with acute otitis media (AOM).
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| 4. Choose the best method of hydration for children with acute gastroenteritis.
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| 5. Describe the role of corticosteroids in pediatric meningitis.
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Discussed on This Program
Amoxicillin (several formulations and trade names]
Amoxicillin and potassium clavulanate (co-amoxiclav) [Augmentin, Augmentin ES-600, Augmentin XR]
Azithromycin [Zithromax, Zmax]
Ceftriaxone sodium [Rocephin]
Cephalexin [Biocef, Keflex]
Clarithromycin [Biaxin, Biaxin XL]
Gatifloxacin [Tequin, Zymar]
Lactobacillus [Bacid, Kala, Lactinex, MoreDophilus, Pro-Bionate, Superdophilus]
Loperamide HCl (several formulations and trade names)
Ondansetron HCl [Zofran, Zofran ODT]
Penicillin G [Bicillin C-R, Bicillin C-R 900/300, Bicillin L-A, Permapen, Pfizerpen, Wycillin]
Penicillin V (phenoxymethyl penicillin) [Penicillin VK, Veetids]
Pneumococcal 7-valent conjugate vaccine (diphtheria CRM197 protein) [Prevnar]
Prochlorperazine [Compazine, Compro]
Suggested Reading
[No authors listed]: Vaccine news: new meningitis vaccine approved for children and should we be giving all
schoolchildren flu vaccine? Child Health Alert 23:1, 2005; Chavez-Bueno S, McCracken GH Jr: Bacterial meningitis
in children. Pediatr Clin North Am 52:795, 2005; Craig JC, Hodson EM: Treatment of acute pyelonephritis in
children. BMJ 328:179, 2004; Dalby-Payne J, Elliott E: Gastroenteritis in children. Clin Evid 13:343, 2005; Ilyas
M et al: Age-related radiological imaging in children with acute pyelonephritis. Pediatr Nephrol 17:30, 2002; Leibovitz
E: Acute otitis media in pediatric medicine: current issues in epidemiology, diagnosis, and management. Paediatr
Drugs 5:1, 2003; Lozano JM et al: Treatment of acute pyelonephritis in children: conclusions should have been more
cautious. BMJ 328:957, 2004; O’Neill P, Roberts T: Acute otitis media in children. Clin Evid 13:227, 2005; Orenstein
SR: Oral rehydration versus intravenous therapy for treating dehydration due to gastroenteritis in children. Curr
Gastroenterol Rep 7:209, 2005; Paradise JL: A 15-month-old child with recurrent otitis media. JAMA 288:2589, 2002;
Reynolds EE: A 15-month-old child with recurrent otitis media, 2 years later. JAMA 292:2515, 2004; Rothman R et
al: Does this child have acute otitis media? JAMA 290:1633, 2003; Schaad UB et al: Cefepine vs ceftazidime treatment
of pyelonephritis: a European, randomized, controlled study of 300 pediatric cases. European Society for Paediatric Infectious
Diseases (ESPID) Pyelonephritis Study Group. Pediatr Infect Dis J 17:639, 1998; Strawser D: Pediatric bacterial
meningitis in the emergency department. J Emerg Nurs 23:310, 1997; Tasic V et al: Imaging of children with culture-
negative acute pyelonepritis. Acta Paediatr 92:1228, 2003;
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship
with the manufacturer or provider of any commercial product or service discussed. For this issue, Dr. Marmor reported
nothing to disclose.
Dr. Marmor was recorded at Topics in Emergency Medicine, presented October 24-27, 2005, by the University of California,
San Francisco, School of Medicine, Department of Medicine, Division of Emergency Medicine. The Audio-Digest
Foundation thanks Dr. Marmor and the University for their cooperation in the production of this program.
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