You are here:
GERMINATION, VIABILITY AND CLEARANCE OF STACHYBOTRYS CHARTARUM IN THE LUNGS OF INFANT RATS
Citation:
Yike, I., S J. Vesper, J. F. Tomashefski Jr., AND D. G. Dearborn. GERMINATION, VIABILITY AND CLEARANCE OF STACHYBOTRYS CHARTARUM IN THE LUNGS OF INFANT RATS. MYCOPATHOLOGIA 156(2):65-67, (2003).
Impact/Purpose:
To understand children's risks from exposure to molds in their environment and to explore risk management options for mitigating those risks.
Description:
The fungus Stachybotrys chartarum has been associated with many adverse health effects including the condition known as idiopathic pulmonary hemorrhage in infants. In order to gain some insight into possible mechanisms, viable conidia of S. chartarum were instilled into the lungs of 4 and 14 day-old rat pups. Germination was observed in the lungs by 24 h in the 4 day old but not until 72 h (and then only rarely) in the 14 day-old pups. Even two weeks after instillation of the conidia, the fungus could still be detected in the lung homogenates, both by dilution plating and quantitative PCR analysis.
In the 4 day-old pups, pulmonary inflammation with hemorrhagic exudates was observed and resulted in about 15% mortality rate compared to 0% for the controls instilled with phosphate buffered saline. In the 4 day-old pups, after 3 days, acute neutrophilic inflammation and intense interstitial pneumonia with poorly formed granulomas associated with fungal hyphae and conidia were obvious. The surviving experimental pups showed significantly slower weight gain for seven days. However, 14 day-old rat pups showed neither the lethal effects of exposures to instilled S. chartarum conidia nor the slower weight gain. Rat pup age may determine the response to exposures to S. chartarum conidia with the youngest pups being less able to clear the conidia resulting in more severe health effects.