
Microbial
biofilms - structured consortium of bacteria that are embedded in layers of
self-produced polymer matrices, largely composed of polysaccharide, protein and
DNA – are well described and known problems for pharmaceutical water systems
and medical devices. What is less well-researched is the association of
biofilms with endotoxin, especially within the pharmaceutical and medical device
context. Here the association of biofilms and endotoxin is of significance to
the risks presented by biofilms to water systems and for patient risks in
relation to medical devices. With water systems the detection of endotoxin may
provide an early warning of a biofilm problem. While the screening of
Water-for-Injection systems for endotoxin is a GMP requirement, other types of
pharmaceutical grade water are not commonly sampled for endotoxin testing. The
introduction of this type of testing may prove useful where there is a concern
about biofilm formation. The same may also apply to medical devices, especially
given the risk posed from endotoxin. Detachment of cells or cell aggregates,
production of endotoxin, increased resistance to the host immune system, and
provision of a niche for the generation of resistant organisms are all biofilm
processes which could lead to infection.
In
relation to this, Tim Sandle has written a review paper. Here is an extract:
The
impact of endotoxin will be variable given that lipopolysaccharide size and
composition are highly dynamic and vary according to the strain and growth
conditions which contribute to the way by which bacteria adapt to changing
environments. Nevertheless, endotoxin can potentially provide earlier warnings
about biofilm developments than are possible with techniques like bioburden
testing and assessments can also assist with the design of materials,
especially those that do not readily bind endotoxin, and with in-use
assessments.
This
article discusses the association of biofilms and endotoxin; looks at the
challenges this association poses for water systems and medical devices; and
considers whether tests for endotoxin can function as part of a detection
method to support an endotoxin control strategy.
The
reference is:
Sandle,
T. (2019) Endotoxin testing as a detection method for bacterial biofilms, American Pharmaceutical Review: Endotoxin
Supplement 2019, 22 (6): 19-21
Posted by Dr. Tim Sandle,
Pharmaceutical Microbiology
No comments:
Post a comment
Pharmaceutical Microbiology Resources