title: Keratoconjunctivitis sicca of human T cell lymphotropic virus type 1 (HTLV-1) infected individuals is associated with high levels of HTLV-1 proviral load.
abstract: BACKGROUND
  A high HTLV-1 proviral load is found in HTLV-1-associated diseases, mainly HAM/TSP. However, the association between proviral load and keratoconjunctivitis sicca (KCS) has not been well established.
  
  
  OBJECTIVE
  To verify the association between KCS and HTLV-1 proviral load.
  
  
  METHODS
  104 HTLV-1 infected patients (51 asymptomatic and 52 with HAM/TSP) from the HTLV reference center in Salvador, Brazil were followed from June 2008 to May 2010. Evaluation of tear secretion was performed by BUT (break-up time), Rose Bengal and Schirmer I tests. The diagnosis of KCS was based upon the presence of symptoms and when at least two of three tests were positive. HTLV-1 proviral load was determined using real-time PCR.
  
  
  RESULTS
  The prevalence of KCS was 44.2%. KCS was more frequent among HAM/TSP patients (p = 0.022). Patients with KCS had higher proviral load (mean 134,672 ± 150,393copies/10(6) PBMC) than patients without the disease (mean 66,880 ± 109,525copies/10(6) PBMC) (p = 0.001). HTLV-1 proviral load>100,000copies/10(6) PBMC increased significantly the risk of developing KCS (OR = 4.05 and 95% CI = 1.40-11.76). After age>45 years and HAM/TSP status were excluded in stepway reward analysis, the variables PVL>100,000 (OR = 4.77 and 95% CI = 1.83-12.44) still remained statistically significant.
  
  
  CONCLUSIONS
  HTLV-1 proviral loads are higher in patients with KCS and may represent a relevant biological marker of disease.
authors.affiliation: Instituto Brasileiro de Oftalmologia e Prevenção da Cegueira (IBOPC), Salvador, BA, Brazil. bgalvao@bahiana.edu.br
authors.forename: Cristina
authors.initials: C
authors.lastname: Castro-Lima Vargens
authors.forename: Maria Fernanda Rios
authors.initials: MF
authors.lastname: Grassi
authors.forename: Ney
authors.initials: N
authors.lastname: Boa-Sorte
authors.forename: Regina Helena
authors.initials: RH
authors.lastname: Rathsam-Pinheiro
authors.forename: Viviana Nilla
authors.initials: VN
authors.lastname: Olavarria
authors.forename: Ramon
authors.initials: R
authors.lastname: de Almeida Kruschewsky
authors.forename: Bernardo
authors.initials: B
authors.lastname: Galvão-Castro
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D001938:Brazil; D002648:Child; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D015490:HTLV-I Infections / Q000175:diagnosis / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D007638:Keratoconjunctivitis Sicca / Q000175:diagnosis / Q000821:virology*; D008297:Male; D008875:Middle Aged; D015493:Paraparesis, Tropical Spastic / Q000175:diagnosis / Q000821:virology; D011533:Proviruses / Q000502:physiology*; D019562:Viral Load
chemical_list: D015415:Biomarkers; D004279:DNA, Viral