Contamination with hepatitis B virus DNA in gastrointestinal endoscope channels: risk of infection on reuse after on-site cleaning.
OBJECTIVE
The incidence of viral contamination in the air, water and suction/accessory channels of gastrointestinal endoscopes was examined in order to evaluate the risk of infection.


METHODS
After endoscopic examinations, including biopsy procedures, in 17 patients who were positive for hepatitis B virus surface antigen and eight patients who were positive for hepatitis C virus antibody, the endoscopes were cleaned on site by suctioning and flushing the air and water channels with an enzyme detergent. First samples were then collected by flushing 5 ml of sterile water through each channel. After mechanical reprocessing, second samples were collected in the same way. Virological studies were carried out with real-time polymerase chain reactions for hepatitis B virus DNA and hepatitis C virus RNA.


RESULTS
Hepatitis B virus DNA was detected in five of the first samples recovered from the suction/accessory channels of the endoscopes (titers of 1.3 x 10 (4) to 2.5 x 10 (5) copies/ml), while no contamination was detected after reprocessing ( P = 0.0445). The first samples from one water channel and three air channels were also positive for hepatitis B virus DNA, but were negative after reprocessing ( P > 0.5, P = 0.227, respectively). No hepatitis C virus RNA was detected in any of the samples.


CONCLUSIONS
These results indicate that all of the channels were potential sources of viral infection.
Ishino
Y
Y
Dept. of Gastroenterology, Jichi Medical School, Tochigi, Japan. ishino@jichi.ac.jp
Ido
K
K
Sugano
K
K
D001706:Biopsy / Q000295:instrumentation; D004279:DNA, Viral / Q000032:analysis*; D003902:Detergents / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods*; D020776:Endoscopes, Gastrointestinal / Q000821:virology*; D004866:Equipment Contamination; D017743:Equipment Reuse; D005976:Glutaral / Q000494:pharmacology*; D006509:Hepatitis B / Q000517:prevention & control / Q000635:transmission / Q000821:virology; D006511:Hepatitis B Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D016133:Polymerase Chain Reaction
D004279:DNA, Viral; D003902:Detergents; D006511:Hepatitis B Antigens; D005976:Glutaral