Evidence for Genetic Regulation of Susceptibility to Toxoplasmic Encephalitis in AIDS Patients

J Infect Dis. 1996 Jan;173(1):265-8. doi: 10.1093/infdis/173.1.265.


The frequency of HLA-DQ antigens in AIDS patients with toxoplasmic encephalitis (TE) were examined. HLA-DQ3 was significantly more frequent in white North American AIDS patients with TE (85.0%) than in the general white population (51.8%; P = .007, corrected P = .028) or randomly selected control AIDS patients who had not developed TE (40.0%; P = .016). In contrast, the frequency of HLA-DQ1 was lower in TE patients than in healthy controls (40.0% vs. 66.5%, P = .027), but this difference did not reach statistical significance when corrected for the number of variables tested (corrected P = .108 for the general white population). HLA-DQ3 thus appears to be a genetic marker of susceptibility to development of TE in AIDS patients, and DQ1 may be a resistance marker. These HLA associations with disease indicate that development of TE in AIDS patients is affected by a gene or genes in the HLA complex and that HLA-DQ typing may help in decisions regarding TE prophylaxis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • AIDS-Related Opportunistic Infections / genetics*
  • AIDS-Related Opportunistic Infections / immunology
  • CD4 Lymphocyte Count
  • CD4-Positive T-Lymphocytes / immunology
  • Disease Susceptibility
  • Encephalitis / genetics*
  • Gene Frequency*
  • Genetic Markers
  • Genotype
  • HLA-DQ Antigens / genetics*
  • Humans
  • Toxoplasmosis, Cerebral / genetics*


  • Genetic Markers
  • HLA-DQ Antigens