title: Clinical relevance of and risk factors for HSV-related tracheobronchitis or pneumonia: results of an outbreak investigation.
abstract: BACKGROUND
  Herpes simplex virus (HSV) type 1 was identified in respiratory specimens from a cluster of eight patients on a surgical intensive care unit within 8 weeks. Six of these patients suffered from HSV-related tracheobronchitis and one from HSV-related pneumonia only. Our outbreak investigation aimed to determine the clinical relevance of and risk factors associated with HSV-related tracheobronchitis or pneumonia in critically ill patients, and to investigate whether the cluster was caused by nosocomial transmission.
  
  
  METHODS
  A retrospective cohort study was performed to identify risk factors for the outcomes of HSV-related tracheobronchitis or pneumonia and death using univariable analysis as well as logistic regression analysis. Viruses were typed by molecular analysis of a fragment of the HSV type 1 glycoprotein G.
  
  
  RESULTS
  The cohort of patients covering the outbreak period comprised 53 patients, including six patients with HSV-related tracheobronchitis and one patient with pneumonia only. HSV-related tracheobronchitis or pneumonia was associated with increased mortality (100% in patients with versus 17.8% in patients without HSV-related tracheobronchitis or pneumonia; P < 0.0001). The interaction of longer duration of ventilation and tracheotomy was associated with HSV-related tracheobronchitis or pneumonia in multivariable analysis. Identical HSV type 1 glycoprotein G sequences were found in three patients and in two patients. The group of three identical viral sequences belonged to a widely circulating strain. The two identical viral sequences were recovered from bronchoalveolar lavages of one patient with HSV-related tracheobronchitis and of one patient without clinical symptoms. These viral sequences showed unique polymorphisms, indicating probable nosocomial transmission.
  
  
  CONCLUSIONS
  HSV-related tracheobronchitis or pneumonia is associated with increased mortality in critically ill patients. Care should be taken to avoid nosocomial transmission and early diagnosis should be attempted.
authors.affiliation: Institute of Virology, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany. engelmann.ilka@mh-hannover.de
authors.forename: Ilka
authors.initials: I
authors.lastname: Engelmann
authors.forename: Jens
authors.initials: J
authors.lastname: Gottlieb
authors.forename: Astrid
authors.initials: A
authors.lastname: Meier
authors.forename: Dorit
authors.initials: D
authors.lastname: Sohr
authors.forename: Arjang
authors.initials: A
authors.lastname: Ruhparwar
authors.forename: Cornelia
authors.initials: C
authors.lastname: Henke-Gendo
authors.forename: Petra
authors.initials: P
authors.lastname: Gastmeier
authors.forename: Tobias
authors.initials: T
authors.lastname: Welte
authors.forename: Thomas Friedrich
authors.initials: TF
authors.lastname: Schulz
authors.forename: Frauke
authors.initials: F
authors.lastname: Mattner
mesh_terms: D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D001991:Bronchitis / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D015331:Cohort Studies; D003422:Critical Care / Q000639:trends; D003937:Diagnosis, Differential; D004196:Disease Outbreaks; D005260:Female; D006561:Herpes Simplex / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D018259:Herpesvirus 1, Human / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D011024:Pneumonia, Viral / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D012189:Retrospective Studies; D012307:Risk Factors; D014136:Tracheitis / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology