Bacteria Unit 2
Sterile body sites vs non-sterile body sites and what constitutes normal flora vs
asterile body sites
● Sterile
a. Blood
b. CSF
c. Sinuses (normally)
● Non-sterile → normal flora (supposed to be there)
a. Respiratory
b. Urine
c. Stool
d. Skin
Bacterial agents associated with bacteremia/sepsis
● Bacteremia → the presence of viable bacteria in the blood, as determined by
growth in the blood culture (may or may not indicate infection)
● Septicemia → bacteremia that reflects true infection and results in systemic
physiological responses that indicate serious infection
○ Ex. shaking, fever, nausea, vomiting, diarrhea, etc.
● S. aureus
● E. coli
● S. epidermidis
● CoNS
● Enterococcus spp.
● Candida albicans
● Klebsiella pneumoniae
● Viridans steptococci
● Strep pneumoniae
● Enterobacter cloacae
● Proteus spp.
● B-hemolytic strep
● Anaerobic: Bacteroides/Clostridium spp.
Bacterial agents associated with meningitis/Differentiating bacteria, viral, fungal,
tubercular meningitis
, ● CSF → provides cushioning and buoyancy for the brain and carries essential
metabolites
○ Made from choroid plexus cells of the third and fourth ventricle
○ Important defense mechanism → blood brain barrier (BBB)
● Meningitis → inflammation of the tissues surrounding the brain and spinal
cord caused by infection
○ GNRs, S. agalactiae → Neonates and infants
○ Listeria monocytogenes → Neonates and old people
○ H. influenzae → Infants
○ S. pneumoniae, N. meningitidis → All except neonates
Leukocytes Glucose Protein Appearance Predominant Cell
Type
Viral meningitis Increased Normal Normal Clear Mononuclear
Lymphocytes
(80 WBCs
Bacterial Increased Decreased Increased Cloudy Polymorphonuclear
meningitis Neutrophils
(800 WBCs)
Tubercular and 100 WBCs Normal/Low Increased Mononuclear
fungal meningitis
Bacterial agents associated with skin/wound infections
- Wound, Tissue, Body fluid
● Pathogens
○ GNR
○ Enterococcus spp.
○ S. aureus
○ Beta Step
○ Yeast
Bacterial agents associated with eye, ear, sinus infections
● Eye, ear, sinus infections
a. All should be direct gram stained
b. Increased PMNs
Sterile body sites vs non-sterile body sites and what constitutes normal flora vs
asterile body sites
● Sterile
a. Blood
b. CSF
c. Sinuses (normally)
● Non-sterile → normal flora (supposed to be there)
a. Respiratory
b. Urine
c. Stool
d. Skin
Bacterial agents associated with bacteremia/sepsis
● Bacteremia → the presence of viable bacteria in the blood, as determined by
growth in the blood culture (may or may not indicate infection)
● Septicemia → bacteremia that reflects true infection and results in systemic
physiological responses that indicate serious infection
○ Ex. shaking, fever, nausea, vomiting, diarrhea, etc.
● S. aureus
● E. coli
● S. epidermidis
● CoNS
● Enterococcus spp.
● Candida albicans
● Klebsiella pneumoniae
● Viridans steptococci
● Strep pneumoniae
● Enterobacter cloacae
● Proteus spp.
● B-hemolytic strep
● Anaerobic: Bacteroides/Clostridium spp.
Bacterial agents associated with meningitis/Differentiating bacteria, viral, fungal,
tubercular meningitis
, ● CSF → provides cushioning and buoyancy for the brain and carries essential
metabolites
○ Made from choroid plexus cells of the third and fourth ventricle
○ Important defense mechanism → blood brain barrier (BBB)
● Meningitis → inflammation of the tissues surrounding the brain and spinal
cord caused by infection
○ GNRs, S. agalactiae → Neonates and infants
○ Listeria monocytogenes → Neonates and old people
○ H. influenzae → Infants
○ S. pneumoniae, N. meningitidis → All except neonates
Leukocytes Glucose Protein Appearance Predominant Cell
Type
Viral meningitis Increased Normal Normal Clear Mononuclear
Lymphocytes
(80 WBCs
Bacterial Increased Decreased Increased Cloudy Polymorphonuclear
meningitis Neutrophils
(800 WBCs)
Tubercular and 100 WBCs Normal/Low Increased Mononuclear
fungal meningitis
Bacterial agents associated with skin/wound infections
- Wound, Tissue, Body fluid
● Pathogens
○ GNR
○ Enterococcus spp.
○ S. aureus
○ Beta Step
○ Yeast
Bacterial agents associated with eye, ear, sinus infections
● Eye, ear, sinus infections
a. All should be direct gram stained
b. Increased PMNs
