title: Delays in initiation of acyclovir therapy in herpes simplex encephalitis.
abstract: BACKGROUND
  Diagnosis of herpes simplex encephalitis (HSE) is based on clinical findings, MRI, and detection of herpes simplex virus (HSV) DNA in cerebrospinal fluid (CSF) using polymerase chain reaction amplification. Delays in starting treatment are associated with poorer clinical outcomes. We assessed the timing of initiation of acyclovir therapy in HSE.
  
  
  METHODS
  Inpatient databases from seven hospitals in Winnipeg, Manitoba were used to identify individuals diagnosed with encephalitis and HSE from 2004 to 2009. The time taken to initiate therapy with acyclovir and the reasons for delays were determined.
  
  
  RESULTS
  Seventy-seven patients were identified; 69 (90%) received acyclovir; in the others a non-HSV infection was strongly suspected. Thirteen patients were subsequently confirmed to have HSE. Acyclovir was initiated a median of 21 hours (3-407) after presentation in encephalitis cases, and a median of 11 hours (3-118) in HSE. The most common reason for delay was a failure to consider HSE in the differential diagnosis, despite suggestive clinical features. Where therapy was delayed in HSE patients, the decision to begin acyclovir was prompted by transfer of the patient to a different service (55%), recommendations by consultants (18%), imaging results (18%), and CSF pleocytosis (9%).
  
  
  CONCLUSIONS
  Delays in initiating acyclovir for HSE are common, and are most often due to a failure to consider HSE in a timely fashion on presentation. In order to improve patient outcomes, physicians should be more vigilant for HSE, and begin acyclovir therapy expeditiously on the basis of clinical suspicion rather than waiting for confirmatory tests.
authors.affiliation: Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Peter S
authors.initials: PS
authors.lastname: Hughes
authors.forename: Alan C
authors.initials: AC
authors.lastname: Jackson
mesh_terms: D000212:Acyclovir / Q000009:adverse effects / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000998:Antiviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D004279:DNA, Viral / Q000134:cerebrospinal fluid; D003937:Diagnosis, Differential; D020803:Encephalitis, Herpes Simplex / Q000134:cerebrospinal fluid / Q000175:diagnosis* / Q000188:drug therapy*; D005260:Female; D006561:Herpes Simplex / Q000134:cerebrospinal fluid / Q000235:genetics; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D000212:Acyclovir