Genotypic study documents divergence in the pathogenesis of bloodstream infection related central venous catheters in neonates

1. Danny Arroyave Zuluaga
Estudiante de III semestre, Medicina
Universidad Pontificia Bolivariana

2. Morphologically Staphylococcus are gram-positive
cocci.
It grows best in the middle mannitol salt
agar and blood.
It is a facultative anaerobic coco.
Producing catalase.
Has medical significance especially S.
aureus, and human addition to it, the S.
saprophyticus and S. epidermidis.

3. Consisting of Gram-positive cocci.
Grows by aerobic respiration.
We can found in the skin of humans and
animals and mucous membranes.
It is sensitive to the antibiotic novobiocin.

4. It is used to determine the genetic
information of an organism, or genotype, and
to distinguish it from the rest.
Viruses or bacteria: extension pathogen-associated
gene characterization diseases.
Human: paternity tests to determine the
existence of kinship.

5. Genotyping can be applied in this case, since
you have to investigate the genetic
information in order to know the genus and
species of the organism, and it is also
important to know that disease can be
associated and patient treatment.

6. To investigate the pathogenesis of
bloodstream infection by Staphylococcus
epidermidis, using the molecular
epidemiology, in high-risk neonates.

7. Sólo se incluyeron 63 de 318 neonatos, de forma
aleatoria.
Sólo neonatos de alto riesgo.
Que tuvieran un CVC por mas de 24h.
Por cada 1000 catéteres, el 15.1 presentaban la
infección, y el 12.6 de los neonatos pesaban
menos de 1500g.
La tasa de mortalidad fue diferente en los
neonatos que tenían un peso menor a 1500g.

8. Catéter Característica
Umbilical Permite tomar sangre de un bebé
en diferentes momentos
Flebotomía
Es la extracción de sangre desde
una vena periférica.
PICC
(Catéter central de inserción
periférica)
Es una forma de acceso
intravenoso que se puede utilizar
durante un período prolongado
de tiempo.

9. Se obtuvieron muestras de sangre de PICC.
Se realizaron hemocultivos con 1.0ml de sangre
del paciente.
Los cultivos que dieron un resultado positivos se
subcultivaron adicionalmente en placas con agar
sangre.
Se determino su pureza y se observar su
morfología y color específico.

10. Las cepas fueron sometidas a pruebas de
catalasa y coagulasa para determinar la
especie.
Los análisis moleculares se realizaron en
Staphylococcus coagulasa negativa.
Se utilizó el sistema RapID STAPH PLUS
(Oxoid) para confirmar su identidad.

11. Son reacciones que amplifican
simultáneamente diferentes secuencias
diana.
Nos permite la detección e identificación
simultanea de distintos genes de interés.

12. Es una técnica de electroforesis en gel de
campo pulsado que permite la resolución de
grandes fragmentos de ADN que no pueden
ser resueltos por electroforesis en gel
convencional.

13. mecA: Le permite a una bacteria la resistencia
a los antibióticos, tales como la meticilina,
penicilina y otros antibióticos similares.
icaAD: Produce una biofilm la cual le da una
multiresistencia a la bacteria

14. Pte 1
Pte 2
Pte 3
Pte 4
Pte 5(negro)
Pte 6
Fig. 1.
Dendogram of genotypic strains of Staphylococcus
epidermidis after fragmentation with restriction enzyme
SmaI and computer analysis of PFGE

15. AUTHOR WHAT DID HE SAY? THEY ARE AGREE? YES
OR NOT
Garland et al...
2008
“Most catheter-related
BSIs in neonates with
PICCs are caused by
CoNS and derive from
intraluminal
contamination”
NO
Mahieu et al..
2001
“Certain manipulations
and disconnection of the
central venous catheter,
which necessitates
disinfection of the
catheter hub, increase
the risk of CABSI, while
other, protect against
CABSI in neonates.
YES

16. 1. Even knowing that it must have a very
good asepsis in these procedures, do not
respect, and something that can cause an
alteration in patients, and therefore the
results.
2. You have to study very well by other adults
and infants, because the pathogenesis is
very different, and the sources of infection
of the CVC can be very different.

17. 3. The study CVC used by phlebotomy, and we
know that this type of puncture presents high
risks of infection and can cause other diseases,
having other ways like PICC having a much
higher margin of safety should be used these to
a study of more reliable results.
4. It must be quickly identified as the mecA gene
and icaAD as to generate a resistance to
antibiotics, are decreasing the chance of survival
of the patient, and increasing the time of
treatment, therefore, cost.