1. Unknown #5
The infant with seizures
S. aureus
• Thomas Rohan
• Jeanette Daniels
• Kristina Arcena

2. Pathogen Id: Staphylococcus aureus
Diagnosis: Acute Bacterial Meningitis.

3. Diagnosis Information Sheet
• Patient name: Jaden Hallens
• Date of Birth: 05/22/11
• Weight: 3.9 kg
• Height: 20.5 in
• Vital signs:
Temperature: 103.6
Pulse: 154
Respiration: 43
B/P: 141/91
Oxygen level: 94

4. Signs and Symptoms
• Irritability
• High pitched cry
• Vomiting
• Fever
• Bulging anterior frontonals
• Lethargic

5. Day 1 and Day 2
• Gram stain resulted
bacilli rod; di-bacilli
observed and cocci.
• Secondary gram stain
resulted Gram (-) rods
and cocci.
• Suspect a pathogen
that causes
Meningitis deduced
from infants signs
and symptoms.
• Blood agar test’s
inconclusive due to
incorrect incubation
temperatures of test
environment. Kristina
initiates new series of
testing on unknown #
5 organism. Thomas
observes results and
orders next series
• of testing.

6. Secondary organism identified.
Escherichia coli identified
from isolating the
organisms.
• FTM: Facultative
anaerobe.
• Motility: (+)
• Catalase: (+)
• EMB :black w/ Green
metallic sheen. Indicative
of E. coli
• HEA: yellow/orange
• TSI: yellow slant/yellow
butt

7. Unknown #5 Results.
• Macromorphology:
Creamy-tan
• Indicative of
Staphylococcus
aureus.
• FTM: (-)
• Catalase: (+)
• MSA:
Colorless/yellow
colonies

8. Unknown #5 Results.
• Hemolysis: Alpha
Prime Beta
Hemolysis.
• Motility: non motile.
• Novo-bio:
susceptable.

9. Results after isolation:
• Oxidase: (-)
• TGA :Black colonies.
• Catalase :(+)
• Coagulase:(+)
• Motility: Non motile
• Staphylococcus
aureus presenting
more evidence as
possible unknown #5
pathogen.

10. Unknown identified as S. aureus
• Coagualase: (+)
• Causative agent for
infant Meningitis
• Sensitivity tests show
appropriate
resistance and
sensitivity for
Staphylococcus
aureus as the
pathogen.

11. Diagnosis: Acute bacterial
Meningitis
• Mode of transmission:
Nosocomial
introduction of
pathogen caused
during surgical repair
of diaphragmatic
hernia after caesarian
birth.

12. Infant mortality rate 20-40%

13. Treatment
• Metastatic spread of
pathogen has occurred.
MSSA: superiority of
beta-lactoms makes a
clear favorite over using
vancomycin.
• Prefered treatment: 2g IV
oxacillin or nafcillin q4h.
• Brain abscess, subdural
empyema & epidural
abscess-requires urgent
neurosurgical consult for
drainage.
• Duration of therapy: 28
days is standard course
of therapy.
• MRSA (Methicillian-
resistant Staphylococcus
aureus) “super-bug”-
resistant evolved to beta-
lactam anti-biotics which
include the penicillins-
methicillin,
dicloxacillin,nafcillin,oxaci
llin as well as
caphalosporins.

14. Treatment continued.
• •Meningitis
• ◦MSSA: nafcillin or oxacillin 2g IV q4h.
• ◦MRSA:
• ■Preferred: vancomycin 15-20 mg/kg IV 12h (consider loading dose;
guidelines recommend 25-30 mg/kg, although we favor 20-25 mg/kg,
particularly in patients with any baseline renal dysfunction). Strive for trough
level ~20 µg/mL.
• ■Alternatives:
• ◦Linezolid 600mg IV q12h (limited data for meningitis but has good CNS
penetration).
• ◦TMP/SMX 5mg/kg (trimethoprim component) q8-12h.
• ■Some add rifampin 600mg PO/IV q24 or 300-450mg IV/PO q12h.
• ■Refractory infection: consider intrathecal vancomycin, 5-20mg daily.
• ◦Duration: 14d.
• ◦CNS shunt infection: remove device. Replace only when CSF cultures
repeatedly sterile.
• •Brain abscess, subdural empyema, epidural abscess
• ◦Consult neurosurgery urgently for drainage.
• ◦Duration: 4-6 wks.

15. If treatment and precautions are
followed infant should recover.

16. If treatment fails the infant expires
due to brain lesions from cerebral
pressure from swollen brain.