Chandran, S.

Macaden, R.

Nagaraj, S.

Yoganand, R.

International Journal of Infectious Diseases

Elsevier - Publisher Connector 

Profile of genes coding for Carbapenemases among resistant acinetobacter species from a tertiary care centre: A laboratory based study 

17th International Congress on Infectious Diseases / International Journal of Infectious Diseases 45S (2016) 1–477 107
Type: Poster Presentation
Final Abstract Number: 41.080
Session: Poster Session I
Date: Thursday, March 3, 2016
Time: 12:45-14:15
Room: Hall 3 (Posters & Exhibition)
Molecular serogrouping of serologically
atypical shigella isolates from South India
D.P. Muthuirulandi Sethuvel ∗, S. Anandan, D.N.
Kumar, B. Veeraraghavan
Christian Medical College, Vellore, Tamil Nadu, India
Background: Shigellae are the causative agents of bacil-
lary dysentery, represents a signiﬁcant public health problem
worldwide especially in developing countries. New serotypes or
subserotypes in Shigella are not uncommon and are reported from
different parts of the world. Notably, atypical Shigella exhibit
greater antibiotic resistance than typical Shigella serotypes and
also found to harbour integrons which has the ability to acquire
resistance genes. The purpose of this work was to amplify rfb
regions (contains the genes coding for the enzymes responsible
for O-antigen synthesis) of non-agglutinating Shigella isolates to
characterize these by endonuclease restriction and to study the
presence of antimicrobial resistance genes (AMR).
Methods & Materials: A total of 3647 faeces specimens were
processed between January to December 2014, among these, 27.5%
(n=176) were identiﬁed as Shigella spp. Eight non-agglutinable
Shigella isolates obtained were included in the study for molecular
characterization. These strains were tested for their antimicrobial
susceptibility against six antibiotics by Kirby Bauer disc diffusion
method. All the isolates were screened for the AMR genes (dhfr1A,
sulII, bla-OXA, bla-TEM, bla-CTX-M, AmpC and qnrA,B,S) by PCR. The
isolates were also ampliﬁed for their O-antigen gene cluster using
Expand long template PCR system and the amplicons were further
restricted using MboII enzyme.
Results: The prevalence of shigellosis during the study period
was 4.8%. The antimicrobial resistance for the atypical Shigella
were 50% for ampicillin, co-trimoxazole (87%), nalidixic acid (37%),
ceﬁxime (12.5%) and all were susceptible to norﬂoxacin and cefo-
taxime. The AMR gene PCR results showed 25% of dhfr1A (n=2),
62.5% sulII (n=5), 50% bla-TEM (n=4), 50% qnrS (n=4) and all the
isolates were negative for bla-OXA, bla-CTX-M and AmpC genes. rfb-
RFLP results showed clearly identiﬁable and reproducible pattern,
six different patterns were obtained.
Conclusion: This study revealed the description of O-speciﬁc
patterns allowing serotype identiﬁcation without the use of antis-
era. Although the number of atypical Shigella strains in this study
was only eight, thorough and strict monitoring of isolation of such
atypical strains would help to understand the actual disease bur-
den caused by the new Shigella serovars and consequently to study
the epidemiology of shigellosis.
http://dx.doi.org/10.1016/j.ijid.2016.02.275
Type: Poster Presentation
Final Abstract Number: 41.081
Session: Poster Session I
Date: Thursday, March 3, 2016
Time: 12:45-14:15
Room: Hall 3 (Posters & Exhibition)
Proﬁle of genes coding for Carbapenemases
among resistant acinetobacter species from a
tertiary care centre: A laboratory based study
S. Nagaraj1,∗, S. Chandran2, R. Yoganand3, R.
Macaden4
1 St. Johns Medical College and Hospital, Bangalore,
Karnataka, India
2 RD Gardi Medical College, Ujjain, India
3 ESICMC and PGIMSR, Bangalore, India
4 St. Johns Research Institute, Bangalore, India
Background: Acinetobacter species are being increasingly
reported to be associated with infections among seriously ill indi-
viduals. These infections are difﬁcult to treat due presence of genes
coding for resistance to most of the available antibiotics. The study
was conducted to identify the presence of commonly described
genes coding for carbapenemases among the isolates.
Methods & Materials: The study was a cross-sectional
laboratory based observational study from a tertiary care hos-
pital. 89 consecutive (single isolate per patient) isolates of
Acinetobacter species were included. Study period: isolates col-
lected during 2011-2012 from clinical samples and molecular
studies done in 2013. Organisms identiﬁed as Acinetobacter
baumanii complex(Acb complex) using biochemical tests were
included in the study. Antibiotic susceptibility test was done
by Kirby Bauer Disc diffusion. Resistance to carbapenems was
conﬁrmed by Microbroth dilution.PCR was done to identify
the presence of the following genes using published primers,
Oxa(23like,24like,58,51like,NDM,VIM and IMP .ERIC PCR was done
to identify if there was any clonal similarity among these isolates.
Results: The isolates demonstrated resistance to nearly all
antibiotics tested except for Netilmicin for which 11%(10/89) were
susceptible.
The samples from which the Acb complex were isolated:
Respiratory secretions(n =60,67%), pus samples(n =25,28%), urine
(n=10,11%) blood 2 and other ﬂuids 3 isolates.
53,(60%) of the samples were from patients admitted to the
intensive care unit.
The common mechanisms of Resistance for carbapenems were
found to belong to the OXA carbapenemases(23) in 92% of
isolates,followed by VIM(65%). Around 82% also had AmpC beta-
lactamases.NDM detected in 12.
ERIC PCR: Isolates showing >90% of similaritywere grouped into
4 different clusters, genetic heterogeneity was noticed among each
cluster.
Conclusion:Acinetobacter speciesthoughpreviously thought to
be contaminants have now gained notoriety as multidrug resis-
tant, hospital acquired pathogens due to acquisition of a number
of resistance genes. Genes coding for Carbapenem resistance iden-
tiﬁed commonly in our study were the OXA 23like and VIM.NDM
was also detected. Considerable heterogeneity was noted by ERIC
PCR.
http://dx.doi.org/10.1016/j.ijid.2016.02.276


file:///data/remote/core/dit/data/elsevier/pdf/59d/aHR0cDovL2FwaS5lbHNldmllci5jb20vY29udGVudC9hcnRpY2xlL3BpaS9zMTIwMTk3MTIxNjMwMjU1Nw==.pdf

Profile of genes coding for Carbapenemases among resistant acinetobacter species from a tertiary care centre: A laboratory based study

Abstract

Similar works

Full text

Available Versions

Elsevier - Publisher Connector

Elsevier - Publisher Connector