Pauli N. AmornkulSomsit TansuphasawadikulKhanchit LimpakarnjanaratSirirat LikanonsakulNancy YoungBoonchuey EampokalapJaranit KaewkungwalThananda NaiwatanakulJennifer Von BargenDale J. HuTimothy D. MastroBureau of EpidemiologyNational Center for HIV/AIDS, Viral Hepatitis, STD, and TB PreventionBamrasnaradura Infectious Disease InstituteHIV/AIDS CollaborationMahidol UniversityThailand Ministry of Public Health2018-09-072018-09-071999-11-11AIDS. Vol.13, No.14 (1999), 1963-1969026993702-s2.0-0032735711https://repository.li.mahidol.ac.th/handle/20.500.14594/25426Background: Two HIV-1 envelope subtypes have accounted for virtually all infections in Thailand: subtype B' (Thai B), found mainly in injection drug users (IDU), and subtype E, found in over 90% of sexually infected persons and an increasing proportion of IDU in recent years. It remains unclear whether there are differences in pathogenesis associated with these HIV-1 subtypes. Methods: From November 1993 to June 1996, demographic, risk, clinical, and laboratory data were collected by enhanced surveillance from HIV-infected inpatients (≥ 14 years) at an infectious disease hospital near Bangkok. HIV-1 subtype was determined by V3-loop peptide enzyme immunoassay (EIA). Because of confounding, multivariate analyses were stratified by risk category and controlled for sex and age. Results: The infecting HIV-1 subtype was determined for 2104 (94.9%) of 2217 HIV-infected patients with complete data: 284 (13.5%) were subtype B', 1820 (86.5%) were E. Specimens from 113 (5.1%) patients were non-reactive or dually reactive on peptide EIA and were excluded. Among IDU, 199 (67.2%) had subtype B', and 97 (32.7%) had E. IDU accounted for 70.1% (199/284) of patients with subtype B' and 5.3% (97/1820) of those with E. Patients infected with HIV-1 subtypes B' or E had similar spectrums of opportunistic infections (OI), levels of immunosuppression, and in-hospital mortality rates. Of patients who did not inject drugs, more patients infected with subtype E had extrapulmonary cryptococcosis than those with subtype B' (adjusted odds ratio, 2.6; 95% confidence interval, 1.28-5.37). Conclusion: HIV-1 subtypes B' and E seem to be associated with similar degrees of immunosuppression and, with one exception, with similar OI patterns. These data do not suggest an association between HIV-1 subtype and differences in pathogenicity.Mahidol UniversityImmunology and MicrobiologyMedicineArticleSCOPUS10.1097/00002030-199910010-00020