Gram Negative Rods Respi Flashcards
What medium is used to culture Haemophilus influenzae?
Chocolate agar
With factor x (hemin) and v (NAD)
Gram negative rods that cause epiglottitis, meningitis and septic arthritis?
Haemophilus influenzae
What phenomenon is shown by Haemophilus influenzae when it grows around Staph aureus colonies?
Satellite phenomenon
What confers virulence to Haemophilus influenzae?
Polyribitol phosphate capsule
Type b - bad (most invasive)
vs.
Anthrax (poly d glutamate)
What window are children most susceptible to Haemophilus influenzae infections?
6 months to 3 years
Decline in maternal antibodies and antibody formation does not start until 3
Characteristic finding in epiglottitis?
Cherry red epiglottis
Stridor, dysphagia
Complication if cherry red epiglottis is manipulated?
Laryngeal spasm
Will need intubation
Most common bacterial and viral cause of exacerbation in COPD?
Bacterial - Haemophilus influenzae
Viral - influenza virus
Compare epiglottitis with LTB
Epiglottitis - Cherry red, due to Hib, thumbprint sign, ceftriaxone
LTB - parainfluenza virus, steeple sign, aerosolized racemic epinephrine
Hib vaccine conjugated to what toxoid and given between?
To diphtheria toxoid
Given between 2-18 months
Special culture medium used for Bordetella pertussis?
Bordet Gengou or Regan Lowe charcoal medium
Virulence factor of Bordetella pertussis that weakens the phagocytic ability of host neutrophils and lymphocytes?
False adenylate cyclase
Grenades
Virulence factor of Bordetella pertussis that permit binding to ciliated epithelial cells in the bronchi?
FHA
Filamentous hemagglutinin
Virulence factor of Bordetella pertussis, toxin thought to be responsible for whooping cough?
Tracheal cytotoxin
What stage of pertussis is the patient MOST contagious?
Catarrhal stage
1-2 weeks with flu like symptoms
Incubation period of pertussis?
7-10 days no symptoms
What stage of pertussis when fever subsides and violent cough develops?
Paroxysmal stage
Final stage of pertussis when attacks become less frequent and secondary complications may develop?
Convalescent stage
Secondary complications of pertussis?
Pneumonia
Seizures
Enceph
DOC for pertussis?
Erythromycin
Also treat household contacts
Primary prevention for pertussis?
DTaP vaccine or DPT
2,4,6,15-18months
Top three causes of atypical pneumonia?
Mycoplasma pneumoniae - small, unable to be stained
Legionella pneumophila - poor uptake of stain
Chlamydia
Special stain used for Legionella pneumophila due to its poor uptake of gramstain?
Silver stain
Legion of the silver pontiac
Legionella pneumophila is a facultative intracellular organism similar to?
M. tuberculosis