Maintaining confidentiality in a look-back investigation of patients treated by a HIV-infected dentist

The spread of human immunodeficiency virus (HIV) from a Florida dentist with acquired immunodeficiency syndrome (AIDS) to several of his patients has generated considerable concern about the risk of HIV transmission during dental treatment. Accordingly, self-reporting of HIV infection and subsequent AIDS by a dentist at our medical center prompted notification and testing of patients at risk. Key features of the notification and testing process were (a) only patients who had undergone procedures deemed to pose appreciable risk of exposure to the dentist's blood were notified, (b) the identity of the dentist was shielded by not including in notification letters any identifying information other than the name of the medical center, and (c) patients' blood specimens were tested promptly for HIV antibodies and results were reported immediately to each patient to minimize the period of anxiety. HIV antibody testing was requested by 41 of the 88 patients to whom notification letters were sent, and all 41 were HIV negative after having undergone 395 procedures by the HIV-infected dentist. Review of the 88 patients' medical and dental records showed that at least 77 had received treatment by other health care providers at the medical center so that they would not be able to ascertain which provider had HIV infection. None of the patients who were notified by the medical center subsequently queried the dentist concerning possible HIV infection. Our experience demonstrates that look-back investigations can be conducted by institutions in a manner that substantially protects the identity of health care workers with HIV infection, minimizes the number of patients discomfitted, and avoids excessive utilization of personnel time. Even greater protection of the identity of health care workers with HIV infection presumably can be achieved when notification is undertaken by a public health agency.