Flashcards in Bacterial infx LRT Deck (100):
Why are LRTIs more severe?
Lungs are generally sterile, and are full of goodies
What are the two major airway defenses?
What is the main mechanism that protects the lungs from particles?
What is pneumonia?
Inflammation of the lung as a result of a bacterial infection
What are the general features of pneumonia? (5)
pleuritic chest pain
What are the respiratory sounds that are present with pneumonia?
What is pneumonia often associated with?
Viral respiratory tract infx
Who is at increased risk for developing pneumonia?
Heart disease, DM, lung issues old and very young
What are the local effects of bacterial infx of the lung, that are produced from the inflammatory immune response?
What are the common virulence factors on bacteria in the lungs? (5)
Capsules, intracellular growth, IgA protease, exotoxins, and LPS
What is accumulated in pneumonia? (4)
Fluid, bacteria, PMNs, and fibrin
What are the pathogens that cause typical pneumonia? (5)
Most gram negative bateria
Which general type of bacteria usually cause typical pneumonia?
What are the pathogens that cause atypical penumonia?
Why aren't CXR 100% diagnostic for the type of bacterial infx?
Changes throughout course of infecion--must use lab results
What are things that can impair the mucociliary escalator? (4)
Viral infections, smoke, EtOH, narcotics
What are the three pathogens that usually cause typical pneumonia?
What does typical pneumonia look like on a CXR?
What does atypical pneumonia look like?
Patchy infiltrate throughout
What is the onset of typical pneumonia? Atypical?
Typical = sudden
Atypical = gradual
What is the facies associated with typical pneumonia?
Typical = toxic appearing
Atypical = normal appearing
Which type of pneumonia has a productive cough?
Typical = productive
Atypical = non-productive
What is the sputum like in typical pneumonia? Atypical?
Typical = Purulent
Atypical = Scant, watery
Which type of pneumonia has an associated fever (usually)?
Which type of pneumonia has pleurisy?
Which type of pneumonia has a consolidation present?
Which type of pneumonia has leukocytosis with a L shift?
What does the CXR usually show for typical pneumonia? Atypical?
Typical = lobar
Atypical = patchy
What is the most common cause of typical pneumonia? Atypical?
Typical = Streptococcus penumoniae
Atypical = Mycoplasma pneumoniae
Which type of pneumonia is also called "walking" pneumonia?
Infection with what bacteria will not follow the general pattern of symptoms of typical/atypical pneumonia?
What are the three major types of complications for pneumonia?
1. Pleural effusion
3. Chronic complications
What are the three hematologic complications that pneumonia have?
2. Disseminated intravascular coagulation
What are the chronic complications that can result from pneumonia?
1. lower arterial oxygen levels
2. weight loss/muscle atrophy
What is pleural effusion?
"excess fluid that accumulates in the pleural cavity, the fluid-filled space that surrounds the lungs. This excess can impair breathing by limiting the expansion of the lungs" wiki
What is aspiration pneumonia?
Introduction of foreign material into the bronchial tree (saliva, food nasal secretions etc). This dilutes surfactant immunity.
What is aspiration pneumonia associated with?
Alcoholics, coma/stroke pts
What is hospital acquired pneumonia usually associated with?
What is the most frequent cause of HOP?
MDR gram negative bacteria
What are the gram negative bacteria that usually cause HOP? (5)
What are the gram positive bacteria that are associated with HOP? (2)
What are the three conditions that should be ruled out when seeing a pulmonary infiltrate?
True or false: if a blood culture from a pneumonia pt is positive for the pneumonia causing agent, this is always a serious condition
What are the diagnostic criteria for evaluating sputum?
Must see >25 PMNs and <10 epithelial cells (to r/o contamination)
True or false: strep pneumo is a normal colonizer of the URT?
What is the gram stain and morphology of strep pneumo
Gram positive cocci
What is the blood hemolysis result of strep pneumo?
What is the test that distinguishes strep pneumo from staph?
Catalase test (is negative for strep)
What are the three test results of hemolysis testing?
Alpha = some RBC destruction
Beta = total RBC desctruction
Gamma = none
Why type of polysaccharide does strep pneumonia?
What are the five most important virulence factors that pneumococcal bacteria produce?
Thick polysaccharide capsule
What is the effect of pneumolysin?
Virulence factor found on strep penumo that forms pores in host cells
What is the role of teichoic acid/peptidoglycan in pneumonia?
What is rust colored sputum specific for (but not sensitive to)?
Is penumococcal pneumoia a self-limiting disease?
Which type of pneumonia is pneumococcal pneumonia
What are the three tests that can be used to diagnose S. pneumoniae? (4)
Gram stain sputum (positive)
Culture (alpha hemolysis)
Urine collection for pneumococcal polysaccharide
What is the bile test result for S.pneumoniae?
What is the test that can differentiate S. pneumonia from Strep mutans? Result?
S. pneumonia is sensitive to it
What is the treatment for S. pneumo?
Empiric therapy with penicillin or macrolides
Serious cases of strep pnuemo should be treated with what?
Azithromycin + cephalosporin
What is the gram stain and morphology of staph aureus?
Gram positive cocci
What is the catalase test result for staph?
What is the coagulase test result for staph aureus? How does this compare to other staph?
Positive, unlike other staph species
What are the virulence factors for staph aureus?
Panton valentine leukocidin?
What is the protein A part of staph aureus do?
Binds Fc portion of an antibody, and coats itself with antibody
What is the panton valentine leukcidin virulence factor that staph aureus produces?
Pore forming cytotoxin that leads to necrotizing penumonia
What is MRSA, and what is it resistant to?
Methicillin resistane staph, that is also resistant to all beta lactams
Is MRSA more virulent?
No, just harder to treat
What is the treatment for MRSA?
vancomycin or linezolid
What is the treatment for staph infections that are not MRSA?
What are the five gram negative, facultative anerobes bacteria that cause pneumonia?
What are the two gram negative aerobes that cause pneumonia?
Which type of bacteria are more likely to be associated with aspiration pneumonia?
Which type of bacteria causes pneumonia more often in patient who already have an underlying disease?
Which type of bacteria produce foul smelling sputum?
Which type of pneumonia are gram negative pneumonias (typical or atypical)?
What are the two labs that can aid in the diagnosis of gram negative bacterial pneumonia?
What is the treatment for gram negative pnuemonias?
Broad spectrum abx with abx synergism, including gentamycin/cephelxxin
What are the three abx used to treat psuedomonas?
What is the gram stain and morphology of klebsiella pneumoniae?
Gram negative rod
Is klebsiella motile or note?
What is the enzyme that klebsiella produces that makes them harder to treat?
Infection with what bacteria results in currant jelly sputum?
What type of pneumonia does klebsiella produce (lobar vs bronchiolar)
What are the two virulence factors that klebsiella has?
What is the treatment for infection with klebsiella?
Same as other gram-negative pneumonias---
What is the gram stain and morphology of pseudomonas aeruginosa? Specialization?
Gram negative rods, with flagella?
Is pseudomonas aeruginosa an anaerobe or aerobe? Oxidase positive or negative? sugar fermentation positive or negative?
Sugar ferment negative
What do pseudomonas aeruginosa colonies smell like?
pseudomonas aeruginosa usually grows where?
hand soaps, water with minimal nutrients, dilute antiseptics
Most infection sources of pseudomonas aeruginosa are what?
Humidifiers, sink traps
What are the other infections that pseudomonas aeruginosa can cause?
Septicemia, UTIs, wound infections, meningitis in severe burns
What are the 6 virulence factors that pseudomonas aeruginosa has?
1. Toxin A
3. Phospholipase C
What is the effect of toxin A that pseudomonas aeruginosa produces?
ADP ribosylation of EF-2
What is the effect of phospholipase C that pseudomonas aeruginosa produces?
What is the effect of pyocyanin that pseudomonas aeruginosa produces?
What is the effect of pyoverdin that pseudomonas aeruginosa produces?
Green fluorescent virulence factor
What is the treatment for pseudomonas aeruginosa?
Ticarcillin or piperacillin plus an aminoglycoside