Résumé : To the Editor: In a letter in the January 16 issue,1 Dr. Edelbaum noted the rarity of reports of the acquired immunodeficiency syndrome (AIDS) in patients on hemodialysis. He speculated about the possible protective effect of renal failure. I would suggest that the absence of AIDS among such patients is more apparent than real. The Centers for Disease Control case definition of AIDS in adults requires (1) the presence of a reliably diagnosed disease at least moderately predictive of a defect in cell-mediated immunity and (2) the absence of another cause of such immunodeficiency other than infection due to human. © 1986, Massachusetts Medical Society. All rights reserved.