Bortadella, Brucella, Nocardia

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The Deets On These 3 Critters

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What is the pathogenesis of Whooping Cough like (its toxins and their paths)?
Pertussis Toxin is the main virulent factor - it helps Bordetella attach to cilia cells in the tracheal or bronchial tree.  The cilia become immobilized and the toxin begins to destroy cilia.  The tracheal cytotoxin also kills ciliated epithelial cells.
This phase of Whooping Cough is characterized by profuse runny nose.
Catarrhal Phase (first phase) - 1-2 weeks, when its most contagious; only period of antibiotic susceptibility.
What is the key characteristics (2) of the Paroxysmal Phase of Whooping Cough, and how long does it last?
The "whoop" cough, and post-tosis vomitting.  Last 2-10 weeks.   
What is different about the new DPaT Vaccine (instead of just the DPT vaccine)?
DPaT has an acellular Pertusis component - it uses the purified protein pertussis toxin instead of pertussis toxin cells.  
How is Whooping Cough detected in lab today?  What used to be popular (what name of Agar plate was associated with this)?
PCR detection of bacterial DNA.  Before - Nasopharyngeal Swab, grow it on a Bordet-Gengou agar plate.  
Who is most at risk for getting Bordetella pertussis?  
Infants <1 year-old.  No immunity built-up.  The immune adult can still pass it on to these children too. 
Give 2 types of people who would most likely present with Brucellosis.
1) The butcher (contracted it from cattle or cattle aborted placenta maybe).  2)Traveler who ate unpastuerized cheese in Mexico.  
What is Brucellosis?  Does this fever peak in the evening or in the morning?
Brucellosis = Undulating Fever.  Peaks at night, goes away in morning.  
What is the relationship between Reticuloendothelial Cells and Brucella?  
Brucella is an intracellular organism - lives within the macrophages of Reticuloendothelial cells (liver, spleen, lymph cells). 
What are 2 ways of preventing Brucella abortus?
Pastuerize milk.  Give all cattle a live attenuated B. abortus vaccine (this is done in the US).  
What antibiotic(s) would you treat Brucellosis infection?
Combination of Tetracycline (Doxycycline) + Aminoglycoside or Rifampin.  *Note: Beta-lactams will not work because the organism lives intracellularly.  Must inhibit protein synthesis.
What is the difference in transmission between Nocardia brasiliensis and Nocardia actinomyces?
N. brasiliensis is contracted cutaneously through direct inoculation.  N. actinomyces is contracted non-cutaneously, usually via respiratory transmission as an opportunistic infection in immunocompromised patients.  
What is one risk factor (characteristic) that someone may have to increase their chance of a Nocardia actinomyces infection?
1) Chronic respiratory problems - increases risk of resp. contraction of N. actionomyces and results in Pneumonia.  2) A second risk factor is anyone taking steroids (decreased immune response) or anyone who is immunocompromised. 
Besides Pneumonia, what is another main clinical presentation with Nocardia actinomyces?
Abcesses on the brain, kidney or lung. 
Morphologically, why is Nocardia often confused with Tuberculosis?
They are both Acid-Fast.