Officials at Forbes Regional Hospital in Monroeville are warning about 200 patients who underwent colon examinations that they may be at risk for infection because the colonoscopes used had not been adequately cleaned.

The risk of infection is extremely low, hospital officials and local and national health authorities said. But certain patients who had colonoscopies at Forbes between Oct. 28 and Feb. 26 nevertheless are being advised to have their blood tested for hepatitis and HIV as soon as possible.

The patients who have responded thus far have expressed emotions that "run the gamut," said Tom Chakurda, a spokesman for the hospital.

"There's concern, anxiety and, in some limited cases, there's anger, to be quite frank," he said. "And every one of those emotions is understandable."

Only patients who underwent procedures with two specific colonoscopes purchased last fall are being notified for testing. Lab workers only recently discovered that the two scopes were not being completely disinfected after each use.

Certified letters went out to those patients last weekend; 69 have responded thus far and 61 have made appointments for tests, Chakurda said.

Testing at the hospital is free. A toll-free hotline, 1-877-854-5450, has been established to provide information only to those patients who have received certified letters and to schedule them for testing. Repeat testing in six months also is recommended.

After being notified of the scope-processing problem at Forbes, the Allegheny County Health Department reviewed all cases of hepatitis B, hepatitis C and HIV reported since September.

"We could find no link to Forbes Regional," said Guillermo Cole, department spokesman. None of the new cases had undergone colonoscopies at the hospital or otherwise had contact with a Forbes colonoscopy patient.

The disinfection problem concerns two colonoscopes -- long, flexible fiberoptic tubes used to look inside a patient's rectum and large intestine -- refurbished by and purchased from Olympus Inc.

Hospital staffers did not immediately notice that the scopes had auxiliary channels, which give doctors additional capabilities for cleaning an examination area. The channels are not used by Forbes doctors and had not existed in other colonoscopes previously used at the hospital, Chakurda said.

"It appears the difficulty arose in not recognizing this was a different model of scope with an additional channel," Chakurda said. "Thus, we did not identify a need to either consult a manual or seek additional training." The unused, unrecognized channels thus were never specifically disinfected.

Laura Tyler, director of regulatory affairs and quality assurance for Olympus America's medical systems group, said all the company's colonoscopes and other types of endoscopes are accompanied by user manuals that contain specific instructions for cleaning.

Chakurda said there were no plans to discipline any staff members in response to the incident. But the hospital will implement a policy that no newly purchased equipment will be used without a training session, regardless of the equipment's similarity to other equipment already in use.

It's not the first time such cleaning concerns have arisen over auxiliary channels in colonoscopes. In 2003, disinfection problems also involving Olympus scopes were reported at hospitals in New York and California, resulting in thousands of patients being screened for hepatitis and HIV.

A possible or probable link between improperly disinfected colonoscopes has been established with two cases of hepatitis C, said Arjun Srinivasan, a medical epidemiologist at the U.S. Centers for Disease Control and Prevention. But so few such cases exist that it is difficult to even calculate the odds of infection from a colonoscope.

"The risk seems to be quite low," he noted.

Olympus issued a safety notice in February 2003 to remind customers of the channel and to stress that it had to be cleaned after each use. Two months later, the U.S. Food and Drug Administration issued its own alert, reminding hospitals that the auxiliary channels needed to be disinfected, regardless of whether they are used.

The CDC's Srinivasan said colonoscopes and endoscopes are such complicated pieces of equipment that problems with disinfecting them crop up from time to time. The CDC is not aware of any widespread or systemic problems with the scopes, however.

In 2002, a bacterial outbreak at Allegheny General Hospital that killed one patient was linked to contaminated bronchoscopes, another type of endoscope used to examine the lungs. Like Forbes, AGH is part of the West Penn Allegheny Health System.

AGH officials blamed the outbreak on a scope-cleaning machine made by Steris Corp., while the company insisted that hospital workers had not used the cleaning machine properly. An FDA investigation was unable to determine the exact cause of the contamination.