08.19 - Pneumonia, CAP Part 1&2 (Cross) - Questions Flashcards
Most of the time, the etiologic agent for CAP is
never identified
Definition of HAP
Appears >48 hours after hospital admission - Was not incubating at time of admission
Leading cause of death among hospital-acquired infections
Pneumonia
Highest risk for HAP is in patients ____
on mechanical ventilation
Gram stain of H Influenze
Gram Positive Diplo
Gram stain of Mycoplasma pneumoniae
Gram stain negative
Gram stain of Strep pneumoniae
Gram positive Diplo
Gram stain of Staph Aureus
Gram positive cocci in clusters
3 Main Categories of Risk Factors for Strep Pneumo
Alcohol/Drugs; Respiratory Tract abnormalities; Abnormal circulatory dynamics
How does alcohol/drug intoxication predispose to Strep Pneumo
Cerebral impairment –> Depressed cough reflex and increased aspiration of secretions
What abnormal circulatory dynamics predispose to Strep Pneumo
Pulmonary Congestion; Heart Failure
Why is sickle cell a risk factor for Strep Pneumoniae
Auto-splenectomy –> Encapsulated pathogens normally cleared from circulation by spleen
3 Main Virulence Factors of Strep Pneumo
Capsule; Lipoteichoic Acid; IgA Protease
Lipoteichoic Acid (Strep Pneumo)
Activates complement, induces cytokine production
IgA Protease (Strep Pneumo)
Enhances ability to colonize mucosa of URT
How is Strep Pneumo dx?
Urinary antigen and Gram Stain/Culture
4 features of Gram Stain/Culture of Strep Pneumo, other than Gram positive diplot lancet
A-Hemolytic; Catalase negative; Optochin Sensitive, Quellung Reaction
Hemolysis, Catalase status of Strep Pneumo
Alpha Hemolytic, Catalase negative
Quellung Reaction
Antibodies bind to capsule and it swells
Which can be used for Strep Pneumo: Ceftriaxone, Amoxicillin, Levofloxacin, Azithromycin
Any
If you have penicillin allergy and bad strep pneumo pneumonia, use what Ab?
Vancomycin
For strains of Strep Pneumo with reduced penicillin susceptibility, use
3rd gen Cephalosporin (Ceftriaxone) or Fluoroqinolones
For whom is Pneumovax recommended
All >65; 19-64 who are at increased risk
For whom is Prevnar recommended
Children and infants
Classic beta hemolytic bug
Strep pyogenes
Optochin test is used to distinguish
S Pneumoniae (sensitive) from Strep Viridans (resistant)
OVR,PS
Optochin Viridans Resistant, Pneumoniae Sensitive
S Pneumoniae pneumonia is usually of the ___ type
Lobar (as opposed to bronchial)
Leading cause of invasive bacterial disease in children, the elderly, and immunocompromised
S. pneumoniae
Most important virulence factor of Strep Pneumo
Capsule
Initial event in invasive pneumococcal disease
Attachment to epithelial cells, enhanced by pili
Cell wall componentes of strep pneumo contribute to
Inflammatory processes
Which strep pneumo component causes much of inflammatory processes
Cell Wall components
Walking pneumonia in 16 y/o
Mycoplasma Pneumoniae
Who gets Mycoplasma pneumonia most commonly
School-age children and military recruits
Most common cause of pneumonia in school-age children
Mycoplasma Pneumoniae
CXR in Mycoplasma pneumonia
usually looks worse than disease
Capsule that protects against phago is a property of
Strep Pneumo
Adhesin
Mycoplasma: Binds to ciliated epithelial cells and causes reduced ciliary clearance