The Chicago AIDS autopsy study: opportunistic infections, neoplasms, and findings from selected organ systems with a...

The Chicago acquired immunodeficiency syndrome (AIDS) autopsy study evaluated the first 38 AIDS autopsies through January 1, 1985 from 14 participating institutions in the Chicago area. A complete analysis of neoplasms and opportunistic infections from this material as well as a discussion of pathologic features that may be associated only with human immunodeficiency virus (HIV) infection is presented and compared with national data. Among the neoplasms nodular Kaposi's sarcoma was present post-mortem in only 15.8% of cases as compared with a national autopsy incidence of approximately 50%. This figure was highly significant (Z = -5.439 where significance occurs at more than +/- 1.96) and indicates that the Chicago AIDS population is distinct from the national AIDS population in terms of Kaposi's sarcoma. There were no parallel differences in possible cofactors to account for this lower incidence in Chicago. Inflammatory Kaposi's sarcoma was present in 3 cases but did not approach the near 100% figure reported by others. A discussion of this entity and possible reasons for confusion in its diagnosis are discussed. Chicago continues to have a low incidence of AIDS for a large metropolitan area (308 cases/million population) and a continuing low incidence of nodular Kaposi's sarcoma reported clinically. We hypothesize that either some as yet unidentified agent, not generally present in the Chicago population at risk for AIDS, is responsible for the initiation of Kaposi's sarcoma or that the particular HIV-1 isolate in Chicago is not associated with this malignancy.