Invasive Radiologic Procedures Pose Low Risk of HIV Transmission From Doctor to Patient

The estimated risk of HIV transmission from doctor to patientduring an invasive radiologic procedure is quite low, slightlyless than the risk during surgery, according to a study from theUniversity of Texas Southwestern Medical Center at Dallas.

An invasive radiologic procedure is any technique that involvesuse of a needle or scalpel and some type of imaging guidance,such as ultrasound, CT, or fluoroscopy, said Dr. Margaret Hansen,of the university's Department of Radiology, who presented thestudy's findings at the 95th Annual Meeting of the American RoentgenRay Society in Washington, D.C. Common invasive procedures includearteriograms, angioplasty, and imaging-guided biopsies and drainages.

The risk of becoming infected with HIV after exposure to infectedblood is 1 in 250, according to previous studies. For a patientto become infected with HIV during a radiologic procedure, theradiologist must be infected and injured in a manner that causesbleeding. Then the radiologist's blood must contact the patientin a way that can transmit the virus. It is estimated that 0.4%to 0.7% of the US population is HIV positive.

Injuries occur less often during radiologic procedures than duringsurgery, according to studies by Dr. Hansen and others. A studyof five surgical specialties by the Centers for Disease Controlfound the rate of recontact (reuse of a contaminated instrument)during surgery to be 29%. The rate of recontact during an invasiveradiologic procedure is 0.2%, according to a survey of membersof the Society of Cardiovascular and Interventional Radiology(SCVIR) conducted by Dr. Hansen.

The current study found that the estimated risk of HIV transmissionfrom doctor to patient during an invasive radiologic procedureis only 0.03 per million procedures, if the radiologist's HIVstatus is unknown. The estimated risk of transmission during surgery,according to previous reports, is 0.01 to 0.9 per million procedures.If the radiologist is known to be HIV-positive, the risk is 7.4per million procedures. The estimated risk during during surgeryis 2.4 to 24 per million procedures, if the physician's HIV statusis known.

On average, an SCVIR member performs 665 invasive radiologic proceduresannually, and this number is rising. However, the estimated riskof HIV transmission from physician to patient is so low that globalpractice restrictions for interventional radiologists are notwarranted, said Dr. Hansen.

Occupational Safety and Health Administration regulations implementedin 1992 make universal precautions, including the use of protectiveclothing and equipment and prohibitions against recapping sharpinstruments, mandatory. "Despite the low risk of HIV transmission,radiologists need to be vigilant about taking all necessary precautionsto enhance procedure safety for everyone," said Dr. Hansen.