A telephone hotline at Forbes Regional Hospital was flooded with calls yesterday following an announcement that some equipment used for colon examinations had not been adequately cleaned.

Also yesterday, the U.S. Food and Drug Administration said it is investigating why hospital workers who cleaned colonoscopes -- the long, flexible instruments used to view the inside of the rectum and large intestine -- failed to disinfect an unused channel inside two of the devices.

About 1,000 calls had been received from Monday through yesterday afternoon, about five times the number of people who actually underwent colon examinations with the affected colonoscopes between October and February, said hospital spokesman Tom Chakurda.

Only those people who had colonoscopies with one of two suspect instruments are at risk for infection, he noted. Some callers may not have realized that only those patients -- all of whom are being notified by certified letter -- were being advised to call the hotline, 1-877-854-5450, for information and to arrange for free testing for hepatitis and HIV.

An FDA spokeswoman confirmed that the agency is reviewing the cleaning problems at the hospital, but did not elaborate on the extent of the probe.

"We're aware of the situation and we're looking into it," spokeswoman Cathy McDermott said.

Certified letters were mailed last weekend to about 200 of Forbes' colonoscopy patients, advising them to have their blood tested for hepatitis and HIV. Chakurda said the hospital has received confirmation that 172 people have received the letter. He said 104 patients have made arrangements for testing and 84 have been tested.

No test results were immediately available, he said, noting patients will be notified seven to 10 days after their tests.

More than one test, however, is necessary to eliminate the possibility of infection. A second test is recommended after six months.

Sometimes, not enough time has elapsed after infection for the initial test to indicate a positive result, said Richard McGarvey, a spokesman for the state Department of Health. And a second test also can suggest when a patient may have become infected.

Hospital officials and health authorities continued to emphasize yesterday that the risk of infection from the two colonoscopes is extremely low.

Chakurda said two scopesrecently purchased by the hospital contained auxiliary channels that doctors could use to cleanse an examination area. He said staffers did not immediately notice that the scopes were equipped with auxiliary channels; the channels are not used by Forbes doctors and did not exist in scopes previously used at the hospital. The hospital plans to implement a policy that no newly purchased equipment will be used without a training session, he said.

An official for the Pittsburgh Regional Healthcare Initiative, a consortium of hospitals, insurers and health plans, praised Forbes officials for their handling of the situation.

"It's not easy to admit an error," said Naida Grunden, the group's communications director. "The first step in fixing a system error is to expose it, and they are offering what they can to every affected patient."

Disinfection problems with colonoscopes also were reported in 2003 at hospitals in New York and California, resulting in the screening of thousands of patients for hepatitis and HIV.

But McGarvey said the case is one of only three known to have occurred in Pennsylvania in recent years regarding colonoscopes or similar equipment.

In December 2003, health officials said about 86 patients at Grand View Hospital in Sellersville, Bucks County, were examined with scopes that were not soaked in an appropriate disinfecting solution.

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