Abstract: During the hot-humid climate in rainy season in the middle and lower regions of Yangtze river, filamentous fungi are easy to grow. The children with severe disease or immunocompromised status treated with blood purification are at high risk of getting nosocomial infection. In June 2021, the Blood Purification Room of Children's Hospital of Soochow University conducted the supervision of monthly microbial culture, and found that filamentous fungi were positive in several dialysis water samples and dialysis solutions, including microbial colony 76 cfu/ml in the initial terminal of the dialysis water from the water treatment room, microbial colony 6 cfu/ml in the dialysis solution from the No.1 dialysis machine, and microbial colony 4 cfu/ml in the dialysis solution from the No.2 dialysis machine. We immediately started an emergency plan, adjusted the dialysis regimen, monitored the inflammation markers and fungal infection indicators, analyzed the causes of filamentous fungi pollution, and revised the disinfection process in the blood purification room during rainy season. The fungal contamination can be effectively eliminated by strictly controlling the disinfection quality, and increasing the disinfection frequency for surfaces, ground, environment, air outlets  in the dialysis room and water treatment room.

Key words: Children's blood purification room, Filamentous fungus, Rainy season, Air culture