title: Higher HTLV-1c proviral loads are associated with blood stream infections in an Indigenous Australian population.
abstract: BACKGROUND
  An association between blood stream infections (BSI) and HTLV-1 seropositivity in Indigenous Australians might result from HTLV-1 mediated inflammation and parasite coinfections that provide portals of entry for bacteria.
  
  
  OBJECTIVE
  To determine whether BSI risk increases with HTLV-1c proviral load (PVL) and to identify the pathogens responsible in the context of HTLV-1 related conditions.
  
  
  METHODS
  Indigenous adults admitted to Alice Springs Hospital, central Australia, were recruited as cases or controls according to whether they had a BSI. Clinical data were extracted from case notes and the hospital pathology database. HTLV-1 serology and PVL assays were then performed and risk factors for BSI were determined for HTLV-1 infected subjects.
  
  
  RESULTS
  Risk factors were compared between 44 cases and 30 controls who were HTLV-1 Western blot positive. In a multivariable model, high HTLV-1c PVL was predictive of BSI during the study period (OR, 9.10; 95% CI, 2.40-34.4). Median (IQR) HTLV-1c PVL (copies per 100 PBL) was 39-fold higher for patients recording any BSI (0.116 (0.009, 0.277)) relative to those who had no BSI (0.003 (0.000, 0.067))(p=0.0007). Mean (SD) PVL for subjects with no BSI (n=27), 1 BSI (n=37) and ≥2 BSI (n=10) during the study period were 0.120 (0.301), 0.271 (0.622) and 0.500 (0.654) copies per 100 PBL, respectively (p=0.0007). Five BSI were associated with possible complications of HTLV-1; strongyloidiasis (3), infective dermatitis (1), HTLV-1 associated bronchiectasis (1).
  
  
  CONCLUSIONS
  Higher HTLV-1c PVL predicts BSI risk; however; most BSI were not associated with recognised complications of HTLV-1 infection.
authors.affiliation: Northern Territory Rural Clinical School/Flinders University, Northern Territory of Australia, Australia; Department of Medicine, Alice Springs Hospital, Alice Springs, Australia. Electronic address: lloyd.einsiedel@nt.gov.au.
authors.forename: Lloyd
authors.initials: L
authors.lastname: Einsiedel
authors.affiliation: Institut Pasteur, Unité EPVO, Département de Virologie, F-75015 Paris, France; CNRS, UMR 3569, F-75015 Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Cassar
authors.affiliation: Northern Territory Rural Clinical School/Flinders University, Northern Territory of Australia, Australia.
authors.forename: Tim
authors.initials: T
authors.lastname: Spelman
authors.affiliation: Northern Territory Rural Clinical School/Flinders University, Northern Territory of Australia, Australia.
authors.forename: Sheela
authors.initials: S
authors.lastname: Joseph
authors.affiliation: Institut Pasteur, Unité EPVO, Département de Virologie, F-75015 Paris, France; CNRS, UMR 3569, F-75015 Paris, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Gessain
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D016470:Bacteremia / Q000453:epidemiology*; D005260:Female; D015490:HTLV-I Infections / Q000150:complications* / Q000453:epidemiology / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D044382:Population Groups; D011533:Proviruses / Q000302:isolation & purification*; D018570:Risk Assessment; D019562:Viral Load; D055815:Young Adult