The main interest in the presence of pseudomonads of any type (including Burkholderia cepacia complex (BCC) – the former Pseudomonas cepacia) is that they are strictly water-borne organisms (deionized water) which is used as the main ingredient in all of the medicaments listed in this report. Gram negative bacilli of this type thrive heartily in deionized water because of the sparse nutritional requirements. Pseudomonas cepacia was first discovered by Walter Burkholder in 1949 while studying the cause of onion rot and gained more recognition in the 1980’s after it was found to cause a 35% death rate in cystic fibrosis patients that became infected, and subsequently was renamed in his honor.
Burkholderia cepacia is from a group of catalase-positive, lactose-negative, gram negative aerobic bacteria. Gram negative bacilli are divided into three biochemical groups based on their metabolism of glucose fermenters, non-fermenters, oxidizers. E. coli, acaligenes and Pseudomonas/cepacia are examples of these three groups, respectively. They are motile due to a polar flagellum. Sometimes referred to as the Burkholderia cepacia complex (BCC) the group is comprised of B. ambifaria, B. anthina, B. cenocepacia, B. cepacia, B. dolosa, B. multivorans, B. pyrrocinia, B. stabilis, B. vietnamiensis and several others. BCC organisms are typically isolated from water, soil and agricultural products.
BCC organisms are naturally multi-drug resistant to many common antibiotics such as polymyxin B and aminoglycosides. There is a special agar called “Oxidation-fermentation polymyxin-bacitracin-lactose (OFPBL) that contains polymyxin (which inhibits most gram negative bacteria, including Pseudomonas aeruginosa) and bacitracin (which inhibits most gram positive bacteria as well as Neisseria sp.). The presence of lactose distinguishes between fermenting and non-fermenting gram negative bacilli by rendering the medium yellow in the presence of lactic acid and bromthymol blue.
The microbe is able to remain viable for many months in harsh conditions such as low and high temperature extremes (12C to 48C) and in the presence of organic solvents, low nutrients, antiseptics, preservatives, antibiotics and preservatives. It has been found to survive for months in water (low nutrient) but for only maybe 1 week on a dry surface. Its ability to survive such conditions is due to its ability to produce a biofilm.
Over the years B. cepacia has become notorious for its ability to grow in the presence of the substances it is supposed to inhibit e.g., benzalkonium chloride in the barber shop and povidone-idoine antiseptics. A famous paradoxical case of antiseptic drug resistance occurred several years ago with the incident of pseudobacteremia where blood cultures grew cepacia but the organism did not come from blood – it came from contaminated PVP-I that was used to decontaminate the blood culture bottle.
Gibraltar recommends adding this organism to preservative challenge testing, disinfectant validations for facilities and USP <61/62> as our experience has indicated that it can be more resistant to standard preservatives than organisms in the current battery of USP methods. It can be noted though that finished product testing can yield false-negative results due to “nutrient shock” when using nutrient rich media. Special cultivation is necessary (pre-enrichment step) confirmatory identification.