title: Is a lumbar puncture necessary when evaluating febrile infants (30 to 90 days of age) with an abnormal urinalysis?
abstract: OBJECTIVE
  Guidelines for the management of febrile infants aged 30 to 90 days presenting to the emergency department (ED) suggest that a lumbar puncture (LP) should be performed routinely if a positive urinalysis is found during initial investigations. The aim of our study was to assess the necessity of routine LPs in infants aged 30 to 90 days presenting to the ED for a fever without source but are found to have a positive urine analysis.
  
  
  METHODS
  We retrospectively reviewed the records of all infants aged 30 to 90 days, presenting to the Montreal Children's Hospital ED from October 2001 to August 2005 who underwent an LP for bacterial culture, in addition to urinalysis and blood and urine cultures. Descriptive statistics and their corresponding confidence intervals were used.
  
  
  RESULTS
  Overall, 392 infants were identified using the microbiology laboratory database. Fifty-seven patients had an abnormal urinalysis. Of these, 1 infant (71 days old) had an Escherichia coli urinary tract infection, bacteremia, and meningitis. This patient, however, was not well on history, and the peripheral white blood cell count was low at 2.9 × 10⁹/L. Thus, the negative predictive value of an abnormal urinalysis for meningitis was 98.2%.
  
  
  CONCLUSIONS
  Routine LPs are not required in infants (30-90 days) presenting to the ED with a fever and a positive urinalysis if they are considered at low risk for serious bacterial infection based on clinical and laboratory criteria. However, we recommend that judicious clinical judgment be used; in doubt, an LP should be performed before empiric antibiotic therapy is begun.
authors: Infectious Diseases Division, Department of Pediatrics, The Montreal Children's Hospital, McGill University Health Center, McGill University, Montréal, Québec, Canada.
authors: Katryn
authors: K
authors: Paquette
authors: Matthew P
authors: MP
authors: Cheng
authors: David
authors: D
authors: McGillivray
authors: Christina
authors: C
authors: Lam
authors: Caroline
authors: C
authors: Quach
mesh_terms: D016470:Bacteremia / Q000150:complications / Q000453:epidemiology / Q000382:microbiology; D015897:Comorbidity; D003955:Diagnostic Tests, Routine / Q000592:standards / Q000706:statistics & numerical data; D005260:Female; D005335:Fever of Unknown Origin / Q000097:blood / Q000134:cerebrospinal fluid / Q000209:etiology* / Q000652:urine; D006776:Hospitals, Pediatric / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016920:Meningitis, Bacterial / Q000134:cerebrospinal fluid / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D017410:Practice Guidelines as Topic; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D012306:Risk; D013129:Spinal Puncture / Q000706:statistics & numerical data*; D019564:Unnecessary Procedures; D016482:Urinalysis; D014552:Urinary Tract Infections / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology