title: Structural normalization of the lymphoid tissue in asymptomatic HIV-infected patients after 48 weeks of potent antiretroviral therapy.
abstract: BACKGROUND
  The hallmark of HIV infection is the involution and destruction of lymphoid tissue. However, very little information exists on the effect of highly active antiretroviral therapy (HAART) on lymphoid tissue structure.
  
  
  OBJECTIVE
  To evaluate the effect of a HAART regimen after 48 weeks on the architecture and cell regeneration of tonsil lymphoid tissue in HIV-infected patients with CD4 T cell counts > or = 500/microl.
  
  
  METHODS
  From June 1997 to February 1998 all asymptomatic HIV-infected patients with CD4 T cell counts > or = 500/microl seen at our unit were offered quadruple antiretroviral therapy. Tonsil biopsies were obtained at baseline and at 48 weeks. Tonsil tissue sections were examined to evaluate structural and immunohistochemical changes by two blinded and independent pathologists. Cell numbers were counted for selected markers in T-dependent zones.
  
  
  RESULTS
  Eleven patients were evaluable, six were excluded because of insufficient or inadequate sampling in at least one of the biopsies. Cellular depletion, plasma cell accumulation and prominent vessels were observed in all cases; three excluded patients with evaluable baseline biopsies showed similar tissue lesions. Follow-up biopsies demonstrated some degree of improvement in all patients. Germinal centres appeared in seven cases that were not seen at baseline. CD4 cell counts increased and CD8 cell counts decreased significantly in lymphoid tissue. An increase in CD45RA+ cells was observed; however, the proportion of CD45+Ki67+ cells did not differ between baseline and 48 weeks.
  
  
  CONCLUSIONS
  This study shows an unexpected range of moderate to severe lymphoid tissue lesions in mildly immunosuppressed HIV-infected patients, which was partly restored after 48 weeks of HAART.
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Virgen de Valme, Ctra. Cádiz s/n, 41014 Seville, Spain. jmacias@cica.es
authors.forename: J
authors.initials: J
authors.lastname: Macías
authors.forename: M A
authors.initials: MA
authors.lastname: Japón
authors.forename: M
authors.initials: M
authors.lastname: Leal
authors.forename: C
authors.initials: C
authors.lastname: Sáez
authors.forename: J A
authors.initials: JA
authors.lastname: Pineda
authors.forename: D I
authors.initials: DI
authors.lastname: Segura
authors.forename: J
authors.initials: J
authors.lastname: Ortega
authors.forename: E
authors.initials: E
authors.lastname: Lissen
mesh_terms: D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D014066:Palatine Tonsil / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D012367:RNA, Viral / Q000097:blood; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D019380:Anti-HIV Agents; D012367:RNA, Viral