Micro: LRT infection Flashcards
Criteria for Chronic Bronchitis.
Cough with excessive mucous production for at least 3 months within a 2 year period.
How can you exclude Acute bronchitis from pneumonia on H and P?
Low grade fever with bronchitis
or no fever at all
3 routes of entry into the lungs for bacteria to cause pneumonia.
- Aspiration of Normal Flora
- Hematogenous Spread from another site
- Inhalation of Aerosols
1 cause of typical pneumonia.
Strep pneumo
Major virulence factor of Strep pneumo.
Capsule
also uses IgA protease, pneumolysin, adhesins
What kind of operation predisposes patients to acquire a Strep pneumo infection?
Splenectomy
Best Tx for Strep pneumo infection.
Ampicillin or Erythromycin
Virulence Factor for Klebsiella p.
Capsule
What groups are at risk for Klebsiella infection leading to pneumonia?
Alcoholics
IC, hospitalized, ventilator
Tx for Klebsiella
Gentamicin, Cipro
What is Klebsiella’s form of antibiotic resistance?
Carbapenamase (only present in some strains)
-this enzyme hydrolyzes carbapenam, a large component of the beta lactam ring
Plate used to diagnose Haemophilus influenza.
Chocolate agar
- Factor V (NAD)
- Factor X (hemin: iron-containing porin)
Salmon Pink sputum.
Staph aureus pneumonia
Presentation of Atypical pneumonia
Non-productive cough
-fever, headache, myalgia, nausea, diarrhea
organisms don’t gram stain well or at all
Cause of walking pneumonia.
Mycoplasma pneumoniae
Virulence factors of Mycoplasma.
Capsule
Adhesins: will bind cilia and destroy them
Rapid test to detect Mycoplasma infection.
Cold Agglutinins (There is actually a disease called Cold Agglutinin Disease, it's autoimmune and patients make IgM autoantibodies against RBCs that agglutinate at lower temperatures. The Mycoplasma antigens have epitomes very similar to RBCs and the body makes IgMs that will recognize Mycoplasma and RBCs simulating the actual disease) just FYI
Describe the pathogenesis of Chlamydophila pneumonia.
Obligate Intracellular with 2 stages
1. Elementary body: the infectious form that enters host cells
- Reticulate Body: metabolically active form that replicates within the host cell
The reticulate body must convert back to an elementary body before it lyses the cells and searches for other host cells
Tx for mycoplasma.
Macrolides or Doxycycline
Tx for Chlamydophila p.
Macrolides or Doxycycline
Pneumonia from handling birds.
Chlamydophila psittaci
Source of Legionella pneumophila.
Water cooling towers, air conditioners
-intracellular and resides inside amoebas
(once humans are infected it invades alveolar macrophages)
Lab plate used to diagnose Legionella
Buffered Charcoal Yeast agar
-requires iron and cysteine
Most common population to acquire a Pseudomonas infection in the lungs.
CF patients
What should you suspect if a patient presents coughing up lots of smelly sputum?
Anaerobe infection
-Bacteroides sp. or Fusobacterium sp.
Tx for anaerobe lung infection.
Metronidazole
2-4 months
Unique characteristic of Bacillus anthracis and its major virulence factor.
Polyglutamic Acid Capsule
VF: anthrax toxin
Bipolar or safety pin staining.
Yersinia pestis (plague)
Tx for Y. pestis
Immediate
- Stretomycin or
- Tetracycline or
- Chloramphenicol
and Isolate them
Unpasteurized milk from cattle, goats, or sheep
Coxiella burnetii (Q fever)
Rabbits
Francisella tularensis
-causes ulceroglandular disease
Treatment for Tularemia
Streptomycin
