International Journal of Clinical Case Reports 2013, Vol.3, No.6, 31
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33
can inhibit microbes biofilm formation on m edical
implants like urinary catheter.
Catheter associated urinary tract infection (CAUTI)
was the se cond most common nosocomial infection
after ventilator associated
pneumonia
(
VAP), affecting
16.3%
of the patients with a urinary catheter (Sallam
et al., 2005). Despite relatively low m ortality rates,
CAUTI represent a large problem in hospitals due to
additional hospital stay and treatment cost. Nosocom-
ial associated urinary tract infection comprise
perhaps the largest institutional reservoir of
nosocomial antibiotic-resistant pathogens (Potic and
Ignjatovic, 2008). Organisms capable of infecting the
urinary tract during catheterization use approaches to
establish infection that are similar to those used by
organisms that cause uncomplicated UTIs (Ja cobsen
et al., 2008).
Clinical observations have established that the
microbial populations within CAUTI frequently
develop as biofilms, directly attaching to the surface
of catheters (Trautner and Darouiche, 2004). One
main strategy for c ontrol and prevention of bacterial
adhesion, on medical implant is changing the surface
properties of implants to prevent the initial attachment
of microorganisms and reduce the number of
persistent pathogens (Moons et al., 2009).
Marine bioactive compounds are frequently strong and
often are highly specific in their defense activities due
to a diversified exposure (Glaser and Mayer, 2009).
Though marine organisms are very sessile, they hold a
brilliant stock of suc h anti-microbial metabolites
factory to avoid formation of host hazardous biofilm
on their own exposed surfaces; provided the
overwhelming majority of planets’ microbial biomass
prefers to be in a biofilm state (Nicolas et al., 1999).
Hence, these organisms can be chosen to isolate the
compound that can be used for inhibition of bi ofilms
and for human use. Hence in the present study the
extracts of two marine sponges were tested against
microbial biofilm formation inhibition in uri nary
catheters.
2
Results and dicussion
Out of the 47 catheters screened, 46 were found with a
biofilm formation. The biofilm formation was heavy
on the catheters, which w ere used for a long t ime.
Catheters that were used for over 3 months had a
dense biofilm matrix. An examination of biofilm that
was detached from the catheter was found to harbour
consortia of microbial communities. Seven species of
microbial strains were isolated from the biofilm
matrix. An assessment of the d ifferent microbes that
constituted the biofilm revealed that the
Escherichia
coli
was a dominant unit in biofilm (30%) followed by,
Proteus mirabilis
(28%),
Staphylococcus epidermis
(17%)
and
S. aureus
(15%)
incidence. The incidence
of
Candida albicans
(11%),
Pseudomonas aeruginosa
(4%)
and
Neisseria gonnorhaea
(1%)
was found less
(
Table 1).
Table 1 Microorganisms screened and identified from infected
urinary catheters
Microorganisms
Occurrence of different micr-
obes in catheter biofilm (%)
Proteus mirabilis
30
Staphylococcus aureus
28
Staphylococcus
epidermidis
17
Pseudomonas aeruginosa
15
Escherichia coli
11
Neisseria gonnorrhaea
1
Candida albicans
4
In the present study six bacterial strains viz.,
Proteus
mirabilis
,
Escherichia coli
,
Staphylococcus epidermis
,
S. aureus
,
Pseudomonas aeruginosa
,
Neisseria gonno-
rhaea
and one fu ngal strain
Candida albicans
were
isolated from the t ips of urinary catheter associated
biofilm. The sensitivity of these microbial isolates was
tested using standard antibiotics and the extracts of
two marine sponges (
Ag
and
Si
).
Three different doses
of the extracts were used to find out the antibacterial
activity on biofilm forming microbes. Of the three
concentrations tested (20 µL, 40 µL and 60 µL) 60 µL
dose of both
Ag
and
Si
extracts showed a good
inhibitory activity of th e extracts of both
Si
and
Ag
was high on
Proteus mirabilis
,
followed by
S.
epidermis
and
S. aureus
(
Table 2).
The maximum inhibition 16.33 mm for
Ag
and
Si
was
observed. This inhibitory effect was h igh when
compared with s tandard antibiotics, Tetracycline.
Between the two sponges
Si
and
Ag
,
the inhibitory
action varied over bacterial isolates to the extracts of
Si
was very effective inhibitory (16.33 mm) the
growth of
C. albicans
when compared with
Ag
(12.33)
at 60 µL dose (Table 3).