Comparison of Mycobactericidal Activity of 12 Kinds of Disinfectants for Mycobacterium chelonae / 병원감염관리

BACKGROUND: Cleaning and disinfection of fiberoptic bronchoscope requires careful attention, especially to mycobacterium species because the contamination of mycobacteria could raise confusion on diagnosis. Recently, we detected contamination of Wydex(R) solution used in bronchoscope washer with Mycobacterium chelonae. In this study, we evaluated the mycobactericidal effect of 12 kinds of disinfectants for M. chelonae. METHOD: To evaluate the bactericidal effect of Wydex(R) 2%, Cidex(R) 2.25%, Cidex(R) 3%, Bacteriokiller (BK) disinfectant, Perasafe(R), HICLO-S(R), Lamicine(R), ethanol, Instrusept(R), Virkon(R), Betadine(R), and Vipon(R) against M. chelonae, culture was performed after exposure of two M. chelonae strains (ATCC 35749, the type strain and the strain isolated from contaminated Wydex(R) solution) to each disinfectant solution. The growth of organism was examined for up to 8 weeks. RESULTS: Growth of M. chelonae (reference strain of ATCC 35749 and isolated strain) was observed after a week incubation for Wydex(R) 2%, Cidex(R) (2.25%, 3%) and control. For BK disinfectant and Perasafe(R), they grew after 2-3 weeks, and 3-4 weeks, respectively. For HICLO-S(R) and Lamicine(R), only the contaminated strain grew after two and three weeks, respectively. For ethanol, Virkon(R), Betadine(R), Vipon(R), and Instrusept(R) , growth was not observed from either strain. CONCLUSIONS: On the basis of these results, Instrusept(R), virkon(R), ethanol, Betadine(R), and Vipon(R) were effective for the disinfection of M. chelonae. Especially, Instrusept(R) was thought to be useful as a disinfectant for bronchoscopes because it has advantages including non-corrosiveness, chemical stability, and non-irritativeness. And additional washing with ethanol might be effective. The finding that strain isolated from contaminated bronchoscopes was more resistant to disinfectants than reference strain suggested that the more resistant strains are selected throughout the improper disinfection.

Screening of Apheresis Platelet Donors for Human Parvovirus B19 by Gel Card Test / 대한수혈학회지

BACKGROUND: As apheresis platelet concentrates are widely used recently, the risk of transfusion associated infections is increased. Parvovirus B19 causes transfusion associated infections especially in chronic hemolytic anemia, haemophilia or immunosuppressed patients. We evaluated the significance of Parvovirus B19 antigen test to be one of the apheresis platelet donor screening test. METHODS: Three hundred forty eight serum (or plasma) samples from apheresis platelet donors were tested for Parvovirus B19 antigen test which was based on haemagglutination in gel technology. The tubes arranged in special gel cards (DiaMed) were added with 25 microL P antigen positive red cell and 10 microL patient's serum and then centrifuged at room temperature, 85 g for 10 minutes without incubation. The result was read and scored from 0 to 4 positive. Also the antibody screening test was performed for all of the positive samples on the Parvovirus B19 gel card test to exclude false positive reaction due to red cell alloantibody. We investigated directed recipient's disease state for all of positive donors and compared the result of the Parvovirus B19 antigen test with the routine screening test. RESLUTS: Six of the 348 samples were positive for Parvovirus B19 antigen test, the frequency was 1.7%. All of the six positive samples on gel card test reveal negative result by the antibody screening test. All of four directed recipients are immunosuppressed states. If the Parvovirus B19 antigen test was included in routine screening test, the rejection rate is expected to be increased about 1.4%. CONCLUSION: Screening for Parvovirus B 19 in apheresis platelet donors is considered to prevent transfusion mediated viral infection of susceptible recipients including immunocompromised patients.