title: Human metapneumovirus infection in hematopoietic stem cell transplant recipients.
abstract: Human metapneumovirus (hMPV) was described in 2001 and has been associated with both upper and lower respiratory tract infection (URTI and LRTI, respectively), especially in children, the elderly, and in immunocompromised patients. The objective of this study was to identify hMPV as the etiological agent of acute respiratory infection in hematopoietic stem cell transplant (HSCT) patients and to determine the clinical features of hMPV infection in these patients.
  
  
  METHODS
  The study was performed retrospectively in 769 respiratory samples obtained from immunocompromised patients submitted to HSCT over a period of 6 years. RNA was extracted by the guanidinium thiocyanate method, and reverse transcription polymerase chain reaction assay was performed to amplify a 928pb fragment of the hMPV N gene.
  
  
  RESULTS
  hMPV was present in 19 (2.5%) samples. The mean age of infected patients was 18.3+/-10.8 (range, 3-41). Sixty-six percent of hMPV infections occurred during autumn, winter, and spring months. Three episodes showed co-infection with more than 1 virus. Two patients (11.1%) were infected a few days into the conditioning period and 9 (50%) in the first 3 months after the transplant. The majority of patients (72.2%) presented URTI alone with flu-like symptoms (cough, fever, headache, wheezing), while 5 patients (27.8%) had LRTI (pneumonia). No patient died from complications associated with the hMPV infection.
  
  
  CONCLUSIONS
  hMPV has been reported as a respiratory pathogen in HSCT patients. We suggest that hMPV infection should be routinely investigated in this population, mainly in children, to prevent nosocomial transmission during transplant proceedings and to avoid the risk of progressing to complications due to LRTI.
authors.affiliation: Laboratory of Virology, Hospital de Clínicas da Universidade Federal do Paraná, Curitiba, Brazil.
authors.forename: M C
authors.initials: MC
authors.lastname: Debur
authors.forename: L R
authors.initials: LR
authors.lastname: Vidal
authors.forename: E
authors.initials: E
authors.lastname: Stroparo
authors.forename: M B
authors.initials: MB
authors.lastname: Nogueira
authors.forename: S M
authors.initials: SM
authors.lastname: Almeida
authors.forename: G A
authors.initials: GA
authors.lastname: Takahashi
authors.forename: I
authors.initials: I
authors.lastname: Rotta
authors.forename: L A
authors.initials: LA
authors.lastname: Pereira
authors.forename: C S
authors.initials: CS
authors.lastname: Silveira
authors.forename: C M
authors.initials: CM
authors.lastname: Bonfim
authors.forename: S M
authors.initials: SM
authors.lastname: Raboni
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D016867:Immunocompromised Host; D015994:Incidence; D008297:Male; D029121:Metapneumovirus / Q000302:isolation & purification*; D018184:Paramyxoviridae Infections / Q000453:epidemiology*; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000821:virology*; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons