Seminario de biologia molecular, tercer semestre medicina Medicina Universidad Pontificia Bolivariana

1. María Camila Rubio González
Semestre III
Universidad Pontificia Bolivariana

2. Klebsiella pneumoniae
● Rod-shaped bacterium
● Morphology: encapsulated
● Gram-negative
● Infection of K. pneumoniae occur in the lungs, where they cause
necrosis, inflammation, and hemorrhage within the lung
tissue.
● This is caused by aspirating oropharyngeal microorganisms into
the lower respiratory tract.
Characteristics:

3. OXA- 48/ KPC and KPC/NDM
OXA 48: Betalactamase
-Has the highest hydrolysis
capacity against carbapenems
-Generates resistance to
penicillins and beta-lactam with
beta-lactamase inhibitor
-Has intermediate sensitivity to
cephalosporins of 3 and 4
generation
KPC: klesiella pneumonie
carbapenemesa
-It produces multiresistance
involving penicillins,
cephalosporins of 3 and 4
generation, quinolones.
-Its main characteristic is the
resistance to ertapenem
NDM: Metalo- Betalactamase
Generates resistance to all antibiotics
except colistin, tigecycline and
phosphomycin.

4. General objective:
Identification of all 100 K. pneumoniae isolates and low
sensitivity to any of the carbapenem group antibiotics
were determined by Vitek-2
Identification of all 100 K. pneumoniae isolates and
low sensitivity to any of the carbapenem group
antibiotics were determined by Vitek-2

5. Métodos
MIC
01 02
Cultivo
Concentración inhibitoria minima
Fundamento: Son medios producidos
a partir de sustancias y nutrientes que
permiten el crecimiento y proliferación
bacteriana
Existen diferentes medios de cultivo y
se escogen según la bacteria que se
desea cultivar
Uso: Cultivar las bacterias estudiadas
para utilizar el MIC
Fundamento: Sensibilidad bacteriana
a una serie de diluciones del
antibiótico, determinando su mínima
concentración, la cual inhibe el
crecimiento bacteriano.
Uso: Determinar resistencia bacteriana
a los antibióticos

6. Fundamento: Separa fragmentos de ADN
induciendo su reorientación por cambios
periódicos en el campo eléctrico.
Uso: Analizar aislamientos de KP para
identificar cuáles eran los patrones
genéticos de las cepas para entender el
comportamiento con la respuesta a los
antibióticos
PFGE
Fundamento: Es una técnica que amplifica de
manera directa un gen o un fragmento de
DNA o indirecta de RNA, presentes en mezclas
de muy diversas fuentes
La técnica se basa en la amplificación
enzimática in vitro que aumenta el número de
copias de una secuencia particular del DNA
Uso: Se utilizó cebadores considerando los
genes más comunes responsables de la
resistencia al carbapenem en Turquía
03 04
Multiplex PCR
Pulsed-field gel electrophoresis

7. Resultados

8. Resultados

9. Discussion
Van Duin D, Doil Y.
The carbapenem resistant isolates in this study were
also resistant to this group of antibiotics. In addition,
resistance rates against the last choice of antibiotics
such as TG and polymyxins are increasing
Nordmann P,
Naas T, Poirel L.
Although carbapenem resistance level can be
significantly differ in KPC producing isolates
Kilic A, Baysallar
M.
The first OXA-48 + NDM-1 producing K.pneumoniae
strain in Turkey was reported by Kılıç et al.

10. Conclusion
● Molecular biology techniques have not only allowed us to identify
multidrug-resistant bacteria, but have also helped us to classify them
genetically, all of which has facilitated the design of treatment schemes and
new antibiotics for the resolution of infectious conditions.
● Bacterial resistance is a serious public health problem. Many researchers
have stated that future pandemics could be triggered by multidrug-resistant
bacteria. Fortunately, thanks to different genetic identification methods such
as PCR, we can characterize and identify these bacteria and prevent their
spread.