Unknown #5 The infant with seizures

S. aureus• Thomas Rohan• Jeanette Daniels• Kristina Arcena

Pathogen Id: Staphylococcus aureusDiagnosis: Acute Bacterial Meningitis.

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

Signs and Symptoms

• Irritability• High pitched cry• Vomiting• Fever• Bulging anterior frontonals • Lethargic

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.

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

Unknown #5 Results.• Macromorphology: Creamy-tan • Indicative of

Staphylococcus aureus.

• FTM: (-)• Catalase: (+)• MSA:

Colorless/yellow colonies

Unknown #5 Results.• Hemolysis: Alpha

Prime Beta Hemolysis.

• Motility: non motile.• Novo-bio:

susceptable.

Results after isolation:• Oxidase: (-)• TGA :Black colonies.• Catalase :(+)• Coagulase:(+)• Motility: Non motile• Staphylococcus

aureus presenting more evidence as possible unknown #5 pathogen.

Unknown identified as S. aureus• Coagualase: (+)• Causative agent for

infant Meningitis• Sensitivity tests show

appropriate resistance and sensitivity for Staphylococcus aureus as the pathogen.

Diagnosis: Acute bacterial Meningitis

• Mode of transmission: Nosocomial introduction of pathogen caused during surgical repair of diaphragmatic hernia after caesarian birth.

Infant mortality rate 20-40%

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,oxacillin as well as caphalosporins.

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.

If treatment and precautions are followed infant should recover.

If treatment fails the infant expires due to brain lesions from cerebral

pressure from swollen brain.