title: Timing and severity of community acquired respiratory virus infections after myeloablative versus non-myeloablative hematopoietic stem cell transplantation.
abstract: BACKGROUND
  Respiratory virus infections are important causes of morbidity and mortality after hematopoietic cell transplantation. Their clinical course can be severe with progression to lower respiratory tract infection, co-infection with serious pulmonary co-pathogens, and high mortality. Non-myeloablative conditioning regimens achieve engraftment without eradication of host hematopoietic cells, which potentially allows for protection against infections commonly seen in hematopoietic cell transplantation patients treated with standard intensity conditioning regimens.
  
  
  METHODS
  We performed a retrospective cohort study to measure the incidence and severity of parainfluenza types 1-4, influenza (A and B), respiratory syncitial virus and human rhinovirus disease in myeloablative versus non-myeloablative versus autologous hematopoietic cell transplantation patients.
  
  
  RESULTS
  The incidences of all respiratory virus infections were similar in the non-myeloablative and myeloablative cohorts but less in the autologous cohort (33/420 [7.9%], 150/1593 [9.4%], and 37/751 [4.9%], respectively, p<0.0001). However, respiratory virus lower tract infections were significantly less common during the first 100 days after transplantation in non-myeloablative patients compared to myeloablative and autologous patients (1/420 [0.2%], 34/1593 [2.1%] and 16/751 [2.1%], respectively, p=0.005. Respiratory virus lower tract infection had high co-infection and attributable mortality rates.
  
  
  CONCLUSIONS
  Respiratory virus lower tract infection during the first 100 days after hematopoietic cell transplantation was less common in persons receiving non-myeloablative conditioning regimens compared to myeloablative conditioning, despite a similar overall rate of acquisition.
authors: Fred Hutchinson Cancer Research Center, Seattle, WA 98102, USA. jschiffe@fhcrc.org
authors: Joshua T
authors: JT
authors: Schiffer
authors: Kate
authors: K
authors: Kirby
authors: Brenda
authors: B
authors: Sandmaier
authors: Rainer
authors: R
authors: Storb
authors: Lawrence
authors: L
authors: Corey
authors: Michael
authors: M
authors: Boeckh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003139:Common Cold / Q000175:diagnosis / Q000209:etiology; D017714:Community-Acquired Infections / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D018184:Paramyxoviridae Infections / Q000175:diagnosis / Q000209:etiology; D018357:Respiratory Syncytial Virus Infections / Q000175:diagnosis / Q000209:etiology; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000209:etiology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors; D014182:Transplantation, Autologous; D014185:Transplantation, Isogeneic; D014777:Virus Diseases / Q000175:diagnosis* / Q000209:etiology; D055815:Young Adult