The National Institute of Environmental Health Sciences and the Centers for Disease Control and Prevention today announced a joint grant to Dorr G. Dearborn, Ph.D., M.D., of the Case Western Reserve University School of Medicine in Cleveland, Ohio, for a study, in mice, of how a black mold, or fungus, causes infant lungs to hemorrhage, often killing them.
If infant mice react like infant humans, the study may help doctors understand, control and perhaps prevent the Stachybotrys atra-related illness which has been serious in at least 34 infants, with bleeding from the lungs, and caused at least ten infants to die over the past four years in the Cleveland area alone.
Dr. Dearborn, who is in the medical school's pediatric pulmonary division, will expose infant mice to the fungus at three to seven days of age, and sacrifice them days to weeks later for microscopic examination of the lungs to understand how the fungus causes lung hemorrhage.
Dr. Dearborn said that, in mice, you can vary the spore exposure and can deliberately expose mice of different ages -- for controlled experiments you could not do in human infants. You can also determine when the resulting lung lesions occur -- and sacrifice the mice for study.
"Since secondary stress from environmental tobacco smoke seems to be involved in the triggering of the overt hemorrhage of the human infants, we'll also look at this and similar variables," Dr. Dearborn added.
Most of the Cleveland cases -- 28 of 34 -- have been reported in a seven zip code cluster area in eastern neighborhoods. Cases continue to occur.
"Concern that there may be a larger number of undetected young infants with this disorder led to the examination of all infant coroner cases over the past three years," Dr. Dearborn said. "This revealed six sudden infant death syndrome cases with evidence of preexisting major pulmonary bleeding -- cases in addition to the 28 patients seen at Rainbow Babies and Childrens Hospital."
Dr. Dearborn also thinks that the disorder probably extends beyond Cleveland. With CDC's Ruth Etzel, M.D., Ph.D., he continues an informal national survey of all pediatric pulmonary centers that so far has identified more than 60 similar cases of lung hemorrhage in infants across the country over the last four years.
The fungi Stachybotrys atra, one of a number of black molds, requires water soaked cellulose to grow, typical in homes where there has been water damage from flooding, plumbing leaks, or roof leaks that soak building materials such as insulation, gypsum board and ceiling tile.
"The spores of this fungus contain very potent mycotoxins--toxins produced by fungi -- which appear to be particularly toxic to the rapidly growing lungs of young infants," Dr. Dearborn explained.
The medical term for the condition observed in infants is pulmonary hemosiderosis. Its symptoms are coughing up blood or nose bleeds, particularly in infants under six months of age, and chronic cough and congestion, with anemia. The disorder requires immediate medical attention.
Case Western has an Internet home page devoted to this disorder. It recommends correction of water problems and a clean-up of mold growth with a solution of one cup of chlorine bleach solution in a gallon of water, with a little soap to remove dirt and oil that may hold the mold.
Mold growth covering large areas should be assessed by the local health department prior to cleanup. The home page address is: http://gcrc.meds.cwru.edu/stachy.htm