gram negative opportunistic infections Flashcards
examples of compromised patients
- decreased or altered immune system
- alterations in innate protective mechanisms
- breach in physical barriers
what are nosocomial infections?
acquired in the hospital
what is the most common cause of gram negative infections?
E. coli
E. coli can cause
- gastrointestinal infections
- UTIs
- bacteremia
- meningitis
What are UPEC
uropathogenic E. coli
what is a bacteriurial infection?
one in which at least 10^5 orbs/ml are present in urine
what is cystitis?
- burning during urination
- change in frequency, urgency, suprapubic tenderness
- typically lower UT but sometimes upper UT
acute pylonephritis
- UTI disseminated to kidney
- flank pain, tenderness, fever, dysuria, frequency, urgency
What is the leading cause of nosocomial bacteremia?
E. coli
bacteremia proceeds from a UTI most often when:
urinary flow is obstructed
what is a K1 capsule?
a polysialic acid capsule similar to that of neisseria meningitidis. because sialic acids are common constituents of host glycoproteins and glycolipids, there is often no immune response against them
what is the hallmark of gram-negative bacteremia?
the systemic reaction to endotoxin or LPS which is life threatening due to sepsis and shock
What is the most common neonatal pathogen?
E. coli
where do chronic infections with p. aeruginosa occur?
lungs, associated with CF or COPD
what toxins does P aeruginosa secrete?
- endotoxin (gram-negative)
- exotoxins:
1) elastases - break down elastin leading to tissue damage
2) phospholipases - break down phospholipids in lung surfactant
