A chemical or other substance in a blood filtering machine is suspected of causing severe eye inflammation in blood transfusion patients in 14 states.
The problem was noticed in mid-December by nurses at 178-bed St. John Medical Center in Longview, Wash., after three cancer patients became nauseated within hours of receiving blood transfusions that had been specially processed to remove white cells called leukocytes. The patients began vomiting, then reported pounding headaches that began behind their eyes, which became bright red and inflamed. Gradually, the symptoms subsided and disappeared within four to five days.
Since then, the federal Centers for Disease Control and Prevention has received similar reports involving 74 patients in 14 states.
A recent CDC report linked the symptoms to transfusions of blood prepared by American Red Cross blood centers, using a filter manufactured by HemaSure of Marlborough, Mass.
Blood used in the first reported cases was processed at the Red Cross' Pacific Northwest blood center in Portland, Ore.
As of early January, the Red Cross had stopped using the HemaSure filters and had quarantined all blood products prepared with the filters since Oct. 1. No cases have been reported since Jan. 8, the CDC said.
Michele Pearson, M.D., an epidemiologist with the CDC's Hospital Infections Program in Atlanta, said the problems are being investigated.
Doctors, however, suspect a chemical or an allergic response to some other contaminant in the collection filtration system.
Pearson said most of the people receiving the red cells were cancer patients who were being treated for solid tumors or who had been treated with cancer-fighting drugs that damaged the bone marrow.
Patients who need blood transfusions on a routine basis generally receive blood without white cells because white blood cells can release cytokine, a cellular component that can cause fever.
Pearson said the CDC is doing detailed epidemiological studies in Michigan, Oregon and Washington -- the three states with the greatest number of cases.
Gene Chin, M.D., a medical epidemiologist with the Oregon Health Division, said 10 of Oregon's 13 cases were people who live in the Salem area.
"We don't think this is a hospital- or clinic-specific problem, but how the blood is distributed," he said.