title: Why are young infants tested for herpes simplex virus?
abstract: BACKGROUND
  The polymerase chain reaction (PCR)-based test to detect herpes simplex virus (HSV) genome in cerebrospinal fluid (CSF) has become the test of choice for diagnosing this infection. The utility of this test in young infants undergoing sepsis evaluations is unknown.
  
  
  OBJECTIVE
  We sought to identify the factors that prompted physicians to include HSV PCR in their evaluation of young infants undergoing lumbar puncture. In addition, the impact of ordering this test on patient management was assessed.
  
  
  METHODS
  This case-control study included infants 0 to 60 days who were evaluated by lumbar puncture at the Alfred I. duPont Hospital for Children over a 5-year period. Case patients had CSF HSV PCR ordered as part of their evaluation and control patients did not.
  
  
  RESULTS
  Eighty-eight case patients and 83 control patients were identified. The median patient age was 12 days and most patients (55%) were male. Both groups were similar in demographics. Herpes simplex virus infection was diagnosed by PCR in 3.4% of cases. The occurrence of a seizure (adjusted odds ratio [OR], 8.3; 95% confidence interval [CI], 1.7-41.0), the performance of CSF enteroviral PCR testing (adjusted OR, 4.7; 95% CI, 1.4-15.8), and the decision to obtain hepatic transaminases (adjusted OR, 5.6; 95% CI, 2.7-11.8) were associated with the decision to perform CSF HSV PCR testing. Use of health care resources associated with PCR testing was considerable.
  
  
  CONCLUSIONS
  The occurrence of a seizure, the performance of CSF enteroviral PCR testing, and the decision to obtain hepatic transaminases were independently associated with the decision to perform CSF HSV PCR testing. Features traditionally associated with neonatal HSV infection, such as elevated numbers of CSF white blood cells or red blood cells, did not appear to influence the decision to perform CSF HSV PCR testing. The yield of testing in this population was low. Clinicians should weigh the benefits of early diagnosis in a few patients against the consequences of excessive testing in this population.
authors.affiliation: Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Kara L
authors.initials: KL
authors.lastname: Davis
authors.forename: Samir S
authors.initials: SS
authors.lastname: Shah
authors.forename: Gary
authors.initials: G
authors.lastname: Frank
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Eppes
mesh_terms: D016022:Case-Control Studies; D002452:Cell Count / Q000706:statistics & numerical data; D002555:Cerebrospinal Fluid / Q000821:virology*; D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data; D004569:Electroencephalography / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D020803:Encephalitis, Herpes Simplex / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D004769:Enterovirus Infections / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D005334:Fever / Q000209:etiology; D006776:Hospitals, Pediatric / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007902:Length of Stay / Q000706:statistics & numerical data; D007964:Leukocytosis / Q000209:etiology; D008111:Liver Function Tests / Q000706:statistics & numerical data; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D016133:Polymerase Chain Reaction / Q000706:statistics & numerical data*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology / Q000821:virology; D018139:Simplexvirus / Q000302:isolation & purification*; D013129:Spinal Puncture; D019564:Unnecessary Procedures