In a first-person special to the Los Angeles Times (, 5/12), Marc Siegel, MD, examines the ethical debate faced by many doctors who learn that an HIV-positive patient may be concealing his status while having unprotected sex with a negative partner.

Dr. Siegel recounts the story of a patient, “Carlos,” who contracted HIV from another one of Siegel’s patients, “Miguel.” Siegel knew that Miguel was HIV positive, but Carlos didn’t. After finding out that he himself was HIV positive, Carlos asked Siegel if he’d known that his partner had HIV.

“You have to ask him,” Siegel replied. “I can’t say.”

According to the article, the encounter, for Siegel, raised questions about the tension between a doctor’s obligation to confidentiality and his moral obligation to help prevent others from becoming infected with the virus.

“If I had known in advance [that the two patients had a sexual relationship], would I have found the legal and ethical basis to warn Carlos?” Siegel asks. “Or would I have had to let it happen?”