Association of HIV-1 Viral Phenotype in the MT-2 Assay With Perinatal HIV Transmission.LaRussa, Philip; Magder, Laurence S.; Pitt, Jane; Sill, Anne; Hillyer, George; Hollinger, Blaine F.; Lew, Judy; McIntosh, Kenneth; Kufera, Joseph; Bremer, Jim; Blattner, William; for the Women Infants Transmission StudyJAIDS Journal of Acquired Immune Deficiency Syndromes: May 1, 2002 Artides: PDF Only Abstract Abstract : A case-control design study was used to investigate the association of maternal HIV-1 phenotype in MT-2 cells at or near the time of delivery with perinatal transmission of HIV-1, controlling for maternal CD4 percentage and duration of rupture of membranes, in 48 transmitting and 96 nontransmitting HIV-1-infected mothers who gave birth between 1990 and 1995. The nonsyncytium-indueing (NSI) phenotype was more commonly seen in transmitting mothers compared with nontransmitting mothers (90% vs. 75%, p = .04). In a multivariable logistic regression model, the following maternal characteristics were significantly associated with HIV transmission: NSI phenotype (odds ratio [OR] = 6.08; 95% confidence interval [CI]: 1.73- 21.35) and log10 viral load (OR = 2.11; CI: 1.19-3.74). Finally, the association of NSI phenotype with transmission was stronger in transmitting women who received azidothymidine during pregnancy compared with transmitters who did not. (C) 2002 Lippincott Williams & Wilkins, Inc.