Transcript Evaluation of the Anaeropack system for Growth of

Evaluation of the Anaero-pack system
for Growth of Clinically Significant
Anaerobes.
MARLY L DELANEY AND ANDREW B
ONDERDOND.
JOURNAL OF CLINICAL
MICROBIOLOGY,Mar.1997,p.558--562.
Presented By:
Dr.Salma Ahmed
M.Phil Thesis part
Introduction.
• Anaerobic bacteria are the causative agents in a wide
variety of human infection of the skin and soft tissues
and the respiratory, gastrointestinal and female genital
tracts.
• Many anaerobes grow more slowly than facultative or
aerobic bacteria .It is critical to optimize growth
conditions to obtain prompt and reliable culture results
Introduction
• Anaeropack, a novel anaerobic atmosphere
generating system, is a disposable oxygen
absorbing and carbon dioxide generating,
sealed, porous sachet for use in anaerobic jars
or pouches.
• The Anaeropack does not require the addition
of water or the use of palladium catalyst.
• The sachet contents become activated on
contact with oxygen.
Introduction
• Once
the Anaeropack is placed into a sealed
container, the atmospheric oxygen in the container is
absorbed and the oxygen level is reduced to less
than 1% in 30 min, Simultaneously carbon dioxide is
generated to a concentration of 18% 12 min.
•The BBL Gas pack Anaerobic system consists of the
Gas pack Hydrogen and carbon dioxide generator
envelop and a room temperature palladium catalyst
in the jar.
Introduction
• The system require the addition of water to
produce hydrogen ,which combines in the
presence of fresh palladium catalyst with
atmospheric oxygen to form water and
produce anaerobic condition . Within 2 h of
incubation at 35 degree c the oxygen
conc is less than 1% and carbon di oxide
is approxymately 4-10%.
Materials and Methods
• Bacterial isolates---A total 150 anaerobic strains
were obtained from the frozen stock culture
collection of the Anaerobic Research laboratory.
• Of the 150 strains, 140 from clinical specimen.
• Ten reference strains from the American Type
Culture Collection (ATCC).
• Coy anaerobic chamber flexible glove box
kept at 35 degree c and filled with an
atmosphere of carbon dioxide ,10%hydrogen
and 80% nitrogen.
M&M
• BBL gas pack system The Gas pak system
included the Gas pak jar with a catalyst
chamber containing new palladium pellets and
the Gas pak Anaerobe envelope.
• Gas pak anaerobe envelope was placed in each
jar and 10 ml 0f water was added to the envelop.
Freshly conditioned palladium catalyst was
added to the jar and the atmospheric conditions
in the jar system were monitored with a
disposible BBLDry Anaerobicindicator
strip(becton dickenson)
M&M
• Anaeropack system included the medium
sized anaeropack rectangular container
and two anaeropack sachets. The
sachets were removed from their foil
packs and placed in the containier along
with disposible BBL Dry Anaerobic
indicator strip to monitor the atmospheric
condition.
M&M
• Media Brucella base agar with 5% sheep
blood containing 0.01 g of both hemin and vit k
1 per litre.BMB.
• Brucella base agar with 5% laked sheep
blood,100 micro gram of kanamycin, 7.5 micro
gram of Vancomycin per ml and 0.01 g of both
hemin and vitamin k1 per litre .(KLV).
• Phenyl ethyl alcohol anaerobic agar with 5%
sheep blood.PEA.
Result
• The rate and quality of growth of the 150
anaerobic bacterial strains grown in a Coy
anaerobic chamber were compared with those
of the same strains grown in three anaerobic
atmosphere generating system ---the
anaeropack system, Gas Pac system and the
anaeropack sachet in the gas pak jar.
• At 24 hrs 95%of the isolates tested grew in the
Anaeropack and Gas pak system better than the
anaerobic chamber.Anaeropack sachetin the
Gas pack jar 96% grew.
Results
• At 48 hrs Anaeropack system performed slightly
better than the Gas pak system.
• A mean growth based on plate growth ,was
determined for each genus tested at the various
incubation periods, and the result following 24
and 48 h of incubation are presented .
• The growth differences seen were not
statistically significant .(p value more than0.05
by paired t test ) for the various genera tested
with the exception of bacteroids and
peptostreptococcus spp.
Results
• Following 24 h of incubation Bacteroids grew
better in al the atmosphere generating system
than in the chamber.
• By 45 h bacteroids isolates grown in the
chamber exhibited growth similar to those of
isolate grown in the atmosphere generating
system .
• However the Anaeropack system singficantly
bettergrowth compared to that in the Gaspac jar
p=0.0107 and p=0.0162 for anaeropac system
and the Anaeropack sachet in the gas pac jar .
Results
• Peptostreptococcus spp grew significantly better in the
atmosphere generating system than in the chamber
following 24 h of incubation (p=.0003,P=.ooo5, P less
than .ooo1) for the Anaeropack system, Gaspak system
and Anaeropack sachet in the Gaspac jar respectively.
• At 48 h peptostrepcoccus spp grew equally in the
chamber and in the Gas pac jar ,whereas growth in the
Anaeropack system was significantly better compared to
that in the chamber or the Gaspak jar(P=0.0438 for the
Anaeropac system and p=0.0182 for the anaeropack
sachet in the Gas pak jar vs chamber, P=0.0024 for the
Anaeropack system and p=o.oo15 for the Anaerpack
sachet in the Gaspak jar vs the Gaspack jar.
Discussion
• The present study indicates that the
Anaeropack sachet along with the
Anaeropack rectangular container is a
highly effective system for creates an
anaerobic atmosphere.
• The Gaspak system failed 15% of the
time.Anaeropack sachets in the Gas pak
jars failed 7% of the time.
Discussion
• The Anaeropack container were brand new.
Where as the Gas pak jar had been used for
several years.
• The anaeropack system is easier to use than
the Gas pak system .
• The initial growth in the Anaeropack system after
24 and 48 h of incubation was equal to or ,in
many cases ,better than growth after incubation
in the chamber or in the Gaspak system.
Conclusion
• The Anaeropack atmosphere-generating
system proved to be highly effective in
establishing and supporting the growth of
clinically significant anaerobic bacteria.
• The ease of setup and maintenance of the
Anaeropack system makes it an excellent
alternative to the Gas pak system.
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