I am trying to help a group deal with contamination of a medical
device by Candida parapsilosis. A rather thick mat of the organism
appears to have grown on a medical device, which is disinfected with
10% bleach and H2O2 in a non-critical area of the device. Yet the
people are concerned that this is happening. I'm about to do some
SEM work to see just how thick the mat is, and to test its sensitivity
as a function of depth (maybe 100-500 cells thick) to 70% EtOH. The
organism I understand can be a pathogen and may be derived from city
water that goes through an RO treatment. The water is not sterile. I
would like to hear from anyone who has worked with this Candida
sp. and how they effectively disinfect their labware (the device
cannot be autoclaved or heated). It is normally in a nutrient medium
at 37 degrees so it is not surprise that something grows in it. The
mat is so thick though that it smells like "beer", I have been told.
Ted Crusberg, Ph.D.