This document analyzes antibiotic susceptibility and clonal distribution of Staphylococcus aureus bacteria found in pediatric patients at a children's hospital in Colombia over an 8-year period. Researchers used PCR, restriction enzymes, and sequencing to detect genes in the bacteria and determine resistance. They found that some samples contained genes indicating resistance to methicillin. The overall goal was to evaluate changes in S. aureus strains and antibiotic susceptibility trends over time in this pediatric patient population.

1. Valeria Ortiz Tabares
Tercer semestre
Universidad Pontificia Bolivariana
2022

2. This is a gram positive bacteria
How its spread
- Physical contact
- Sharing personal stuff
- Cough and sneezes
It causes:
- Food poisoning
- Bacteremia
- Septic arthritis
Staphylococcus aureus

3. Antifungal resistance: it occurs
when viruses, bacteria and fungi
fight off the medicine effect.
ANTIBIOTIC
SUSCEPTIBILITY
The staphylococcus aureus is
resistant to methicillin

4. OBJECTIVE
The overall objective is to evaluate clonal
Distribution and Antibiotic Susceptibility of
Staphylococcus aureus from Pediatric
Patients: 8-Year Trends in a Children’s
Hospital in Colombia.

5. METHODS
PCR
It´s a polymerase chain
reaction , it finds the DNA
and RNA of a pathogen
➔ They used a multiplex PCR to
detect nuc, mecA and
lukS/lukF-PV genes
➔ They amplified 7 housekeeping
genes such as arcC, gmk, aroE,
glpF, pta, tpi and yqil
RESTRICTION OF ENZYMES
The restriction enzyme prevents
replication of the bacterial DNA
by cutting it into many pieces.
➔ They used HhaI
(restriction enzyme) that
amplified product for the
gmk gene

6. METHODS
SEQUENCING
It is used to determine
de orden of bases
within DNA.
The fragments of DNA
were subjected to
sequencing.
ANTIBIOTIC SUSCEPTIBILITY
It detects an inducible
resistance.
The D-zone test for
inducible clindamycin
resistance was performed
for all the isolates resistant
to erythromycin to detect
the inducible MLSB (iMLSB)
phenotype.

7. RESULTS
ATCC 29213, SA-6, SA-7- it only has the nuc gene

8. RESULTS

9. DISCUSSION
AUTHOR STATEMENT AGREE / DISAGREE
Chambers H F et al “Epidemic clones of MRSA have disseminated glo- bally with some of them reaching high
prevalence in different geographical areas.”
✅
Melles DC et al “Analysis of the population structure of pathogenic S. aureus clones has
determined that certain clones are more virulent than others.”
✅
Choo EJ “The emergence of community- associated MRSA (CA-MRSA) strains in healthcare settings
has changed the hospital epidemiology of MRSA in the last few years.”
✅

10. CONCLUSION
Through molecular biology we can analice
how some type of bacteria and viruses
can identify their resistance to certain
type of antibiotics.
Using different studies all followed up by
molecular biology it can identify different type of
antibiotics that a the Staphylococcus Aureus is
resistant to, this information can be used later to
treat infections caused by this gram positive
bacteria.