title: Clinical features of cytotoxic CD8+ T-lymphocyte deficiency in chronic rhinosinusitis patients: a demographic and functional study.
abstract: BACKGROUND
  Identification of Staphylococcus aureus intracellularly in chronic rhinosinusitis (CRS) suggests an underlying cellular immunodeficiency. Supporting this, we have previously reported low CD8+ (cytotoxic) T-lymphocyte levels in a subpopulation of CRS patients and identified polymorphisms in the CD8A gene associated with CRS. In order to better understand the role of low CD8+ in CRS, we wished to determine the phenotype for CRS/Low CD8+ in comparison to that of conventional CRS.
  
  
  METHODS
  Sixty-seven low CD8+ CRS patients identified during investigation of CRS were compared for demographics, disease evolution, and bacteriology on endoscopic culture were compared with an existing population of 480 patients with CRS with nasal polyposis previously recruited for genetic association studies.
  
  
  RESULTS
  Mean level of CD8+ in the CRS/Low CD8+ population was 0.15 × 10(9)/L (range, 0.20-1.5 × 10(9)/L). There was no difference between both groups in terms of history of allergy, asthma, eczema, acetylsalicylic acid (ASA) intolerance or smoking. The bacteriology was similar between both groups (S. aureus: CRS/Low CD8+: 35%; CRS 32%, p = 0.643). Evolution of disease was somewhat milder in CRS/Low CD8+, with fewer patients requiring surgery, and first surgery performed at a more advanced age. However, antibiotic use was higher in CRS/Low CD8+. Subgroup analysis restricted to CRS with nasal polyposis (CRSwNP)/Low CD8 or CRS without nasal polyposis (CRSsNP)/Low CD8 phenotypes did not substantially alter these results.
  
  
  CONCLUSIONS
  Low CD8+ levels are often identified in CRS patients; however, these patients have disease remarkably similar to those with conventional CRS. This suggests that immune deficiency, whether systemic or locally mediated, is well tolerated and may be present in other forms in CRS. CRS patients with low CD8+ levels may possibly require antibacterial therapies as part of ongoing management.
authors.affiliation: Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Gabra
authors.forename: Saud
authors.initials: S
authors.lastname: Alromaih
authors.forename: Leandra Mfuna
authors.initials: LM
authors.lastname: Endam
authors.forename: Rose Marie
authors.initials: RM
authors.lastname: Brito
authors.forename: Françoise
authors.initials: F
authors.lastname: Larivière
authors.forename: Sawsan
authors.initials: S
authors.lastname: Al-Mot
authors.forename: Françoise
authors.initials: F
authors.lastname: LeDeist
authors.forename: Martin
authors.initials: M
authors.lastname: Desrosiers
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D002478:Cells, Cultured; D002908:Chronic Disease; D018450:Disease Progression; D004363:Drug Utilization / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000188:drug therapy / Q000276:immunology* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009298:Nasal Polyps / Q000188:drug therapy / Q000276:immunology* / Q000382:microbiology; D012220:Rhinitis / Q000188:drug therapy / Q000276:immunology* / Q000382:microbiology; D012852:Sinusitis / Q000188:drug therapy / Q000276:immunology* / Q000382:microbiology; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000276:immunology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents
keywords: Bacteriology; chronic rhinosinusitis; disease severity; immunodeficiency; rhinosinusitis; superantigen