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Discussion Starter · #1 ·
A 35-year-old female with a history of SLE and sporadic serious illness presents with a high fever and dyspnea of acute onset. Chest x-ray reveals bilateral infiltrates, and microscopic examination of sputum smears was inconclusive. Empirical broad-spectrum antibiotic therapy and supportive measures were begun, but the patient died two days after admission. A lung sample obtained on biopsy (below), shows infection with what organism?



  • Blastomyces dermatitidis
  • Cytomegalovirus
  • SNV hantavirus
  • Pseudomonas aeruginosa
  • Streptococcus pneumoniae
 

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The most correct answer is A) Blastomyces dermatitidis

I see a doughter cell attaches to the mother cell at a wide bud base. In this qn the pt is experiencing an acute illness like bacterial pneumonia, with symptoms of high fever, dyspnea, and productive cough.

Tx Itraconazole given orally.

Very good qn, plz post more, thank you
 

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Discussion Starter · #8 ·
A. is correct!

Jorgemorales and aktorque are correct - the answer is A. Blastomyces dermatitidis. The rounded budding yeast forms of blastomycosis are shown here (image from NEJM).
  • CMV was the trap foil - the "owl's eyes" of CMV are inclusions with perinuclear halos. As Sandeep pointed out, there are several things which might look like owl-eyes: RS cells, CMV inclusions, giardia, lacunar cells... it's easy to fall into a trap.
  • While you might see abnormal leukocytes and other indications of SNV hantavirus pathophysiology on a normal stain, you would need immunostaining to localize SNV.
  • Pseudomonas would show up as gram-negative rods, much smaller than cells, and pneumococcus would show gram-positive diplococci.
Meka and jorgemorales were right when they pointed out the SLE Hx as indicating possible immunosuppression. Thanks for the Tx, aktorque!
:)

Here are some pictures to help differentiate some owl-eye-looking things:



Above, blastomycosis again
Below, cyotmegalovirus



Above, cytomegalovirus
Below, Reed Sternberg cells



Above, Reed Sternberg cells
Below, Giardia lamblia

 
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