Medical clinicians - doctors, nurses, and physician assistants - are less likely than dentists and dental hygienists to notice oral lesions that indicate infection with the human immunodeficiency virus (HIV).

A study in New York, Illinois, California and Washington, DC involved 355 women with HIV. Each woman visited a dental clinician and a medical clinician within a one-week time span. The clinicians looked for and described any oral lesions they found, and gave a preliminary diagnosis for each lesion. Before the study began, all the health-care providers were trained in how to identify HIV-related oral lesions.

Medical clinicians recognized only 40 percent to 75 percent of the HIV-related oral abnormalities found by dentists and dental hygienists. They also were much less likely (12 percent to 20 percent) to diagnose the lesions correctly. The major oral lesions found in the study were candidiasis, a fungal infection, and hairy leukoplakia, an infection caused by the Epstein-Barr virus.

Dental professionals found at least one suspicious lesion in 135 of the women. Medical professionals identified only 61 of these women (45 percent) as having at least one lesion.

If a woman saw a dentist on day 1 and a doctor on day 7, oral lesions could have changed over that time period and affected what the doctor saw compared with the dentist. The study did not find this to be the case, however.

"We found that inter-exam interval was not an issue, so diagnostic expertise seemed to be the only other variable," said Joan F. Hilton, Sc.D., M.P.H., first author on the study. "We're not trying to say that only dentists can do these exams, but medical clinicians need more training."

Oral lesions occur relatively early on in the course of HIV infection. More importantly, they may be the only specific indicator of HIV. Most other early symptoms of HIV infection — fever, nausea, fatigue, aches and pains — can be attributed to many other diseases or conditions. The presence of oral candidiasis or hairy leukoplakia indicates a weakened immune system, which is a hallmark of HIV infection.

The importance of oral lesions in diagnosing HIV infection has been shown in many studies. The results of this study only strengthen that. "If clinicians who see these lesions tend to underdiagnose them, but the lesions are still noted as strong predictors of AIDS, then their value as signals [of HIV infection] must be even stronger than we thought," said Dr. Hilton, an associate professor of biostatistics at the University of California San Francisco School of Medicine.

The study was published in the October issue of Community Dentistry and Oral Epidemiology.