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Discussion Starter · #1 ·
A 16 yr old girl is brought to the physician becouse of redness and yellowish discharge from her left eye over the past 2 days.she has had minimal crusting upon awakening in morning but has not had eye pain or previous trauma. physical examination shows diffuse cunjuctival hyperemia and mucoid discharge. The pupils are reactive to the light, but there is mild photophobia of the affected eye. gram stain of exudate shows pleomorphic gram negative bacilli. which of the following is necessary to culture the most likely causal organism on a blood agar plate?

A) Antibiotics to inhibit nornal flora
B) Cold temperature
C) Egg-yolk Cholesterol
D) Reduced oxygen tension
E) Staphylococcal aureus on blood agar
 

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This girl must be suffering from Neisseria gonorrhoeae conjuctivitis (crusting after sleeping, mucoid dishcarge, Gram-negative organisms).

Neisseria gonorrhoeae is cultivated in Thayer-Martin medium, a selective medium that is actually a chocolate agar with the addition of antibiotics (vancomycin, colistin, nystatin -- VCN). So, the correct answer must be A.
 

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Discussion Starter · #4 ·
yup its E

its E Staphylococcal aureus on blood agar

here the pt is suffering from cunjuctivitis caused by haemophillus influenza....
Remember, Acute bacterial conjunctivitis, chiefly affecting young children, is generally caused by one of three common pathogens, Haemophilus influenzae, Streptococcus pneumoniae and adenovirus. H. influenzae is the most prevalent causative organism. Some patients presenting initially with conjunctivitis subsequently develop acute otitis media, with H. influenzae the most common etiologic agent of what has been termed the "conjunctivitis-otitis" syndrome.
heamophilus is very fastidious organism, it requires factor V and factor X for its growth which must be released from whole blood preparation for its use..and its possible by RBC lysis either by Heating or co culturing with staphylococci...a beta haemolutic organism....:rolleyes:
 

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its E Staphylococcal aureus on blood agar

here the pt is suffering from cunjuctivitis caused by haemophillus influenza....
Remember, Acute bacterial conjunctivitis, chiefly affecting young children, is generally caused by one of three common pathogens, Haemophilus influenzae, Streptococcus pneumoniae and adenovirus. H. influenzae is the most prevalent causative organism. Some patients presenting initially with conjunctivitis subsequently develop acute otitis media, with H. influenzae the most common etiologic agent of what has been termed the "conjunctivitis-otitis" syndrome.
heamophilus is very fastidious organism, it requires factor V and factor X for its growth which must be released from whole blood preparation for its use..and its possible by RBC lysis either by Heating or co culturing with staphylococci...a beta haemolutic organism....:rolleyes:
Thanks . i was just gonna choose A. Guess i was wrong
 
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