This document summarizes a study characterizing Clostridioides difficile isolates recovered from hospitalized patients and environments in Iranian hospitals. 700 stool samples and 1435 environmental air samples were collected and tested using pulsed-field gel electrophoresis to differentiate genetic patterns. Isolates were also tested for antibiotic resistance using minimum inhibitory concentration assays. The results found genetically diverse C. difficile isolates in patients and hospital air, with some isolates showing resistance to antibiotics like metronidazole and ciprofloxacin. The study provides evidence of C. difficile in hospital environments that could impact acquisition of infection in patients.

1. Mariana García Campuzano
Medicine student
Third semester 2019-2
UPB

2. INTRODUCTION
2
The toxin produced by
them is responsible for
gastrointestinal
diseases associated
with antibiotics
Most important cause
of
pseudomembranous
colitis
Bacterial species of gram
positive bacilli
It is part of the normal
intestinal microbiota in
a small number of
healthy individuals and
hospitalized patients
Anaerobes
Is resistant to most
antibiotics, moreover,
it is able to grow under
those conditions
CLOSTRIDIOIDES DIFFICILE

3. INTRODUCTION
3
C. difficile infection commonly occurs by
direct contact
with contaminated surfaces, health workers,
visitors or
patient to patient
Contamination of surfaces with toxigenic and
hypervirulent C. difficile strains can generate an
alarm about the acquisition of infection,
particularly in seriously ill patients

4. GENERAL OBJECTIVE
4
Characterize isolates of
Clostridioides difficile
recovered from
hospitalized patients and the
hospitals environment and air

5. MATERIALS AND METHODS
5
The study was developed
between April 2016 and August
2017 in 4
tertiary hospitals of Tehran, Iran
*Characteristics of the study
A total of 700 stool samples were
obtained from hospitalized patients
aged between 2 to 95 years old,
suspected of Clostridioides difficile
infection
A total of 1435 environmental
air samples were collected
from hospital surfaces and
equipment .

6. 6
Pulsed field gel electrophoresis process
(PFGE)
For what?
Allow the differentiation and
classification of different genetic
patterns of a microorganism
Materials and methods
Its foundation
Separation of samples of
DNA, RNA or other
macromolecules according
to their size and charge
using a special gel

7. 7
Polymerase Chain Reaction (PCR)
For what?
Amplify a DNA fragment
gene or an RNA through
an in vitro enzymatic
reaction
Its foundation
Replicate strands of DNA
with a DNA polymerase
using a primer
Materials and methods

8. 8
Minimum inhibitory concentration
(MIC)
For what?
Confirm the resistance of
microorganisms to an
antimicrobial agent, and
analize the activity of new
antimicrobial agents
Its foundation
inhibits the growth of a
microorganism after its
incubation
Materials and methods

9. The isolate PC111 and PC118, include a
identical pulsotype (PT18), that is because
they have the same banding, but respect
to the others, they keep conserving
differences
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RESULTS

10. The ones that have more differences are
the pulsotypes PT29 and PT30
10
RESULTS

11. The isolate ECD41, is resistant to some
antibiotics like Ciprofloxacin, Levofloxacin,
Clindamycin
11
RESULTS

12. The isolate ECD47 is resistant to
antibiotics like Metronidazole,
Ciprofloxacin, Tetracycline
12
RESULTS

13. DISCUSSION
13
AUTHOR CONCEPT YES OR NO
Dubberke E.R etal
“Contamination of surfaces
with toxigenic and
hypervirulent C. Difficile strains
can raise an alarm about the
acquisition of infection
particularly in severely-ill
patients”
Bahani A etal
“The antibiotic-resistant
phenotypes of clinical C.
Difficile isolates were
previously recognized in
patients who had been
admitted to the target
hospitals of the current study.”
Fawley W.N etal
“CE-ribotyping was performed
for the isolates that were non-
typeable by PFGE due to DNA
degradation”
Kikuchi E etal
“All the clinical, environmental
and aerial C. difficile isolates
that were phenotypically
confirmed were examined for
C. difficile 16S rDNA specific
gene”

14. CONCLUSIONS
The study provided evidence of the presence of
the C. difficile population in the hospital air and
its patients, obtaining genetically diverse and
hypervirulent isolates.
14
Investigations as this one shows the impact that
molecular biology has in the medical field,
allowing through its rapid and precise techniques,
the easy obtaining of a clinical diagnosis,
especially when it is a infectious diseases or
cancer.