1. Clayton Wiley, M.D., Ph.D.

2. Question 1
The patient is a 56 year-old male S/P lung transplantation 2 years previously, presenting with altered mental status. Patient was well until 2 months ago when he developed a facial droop and left sided weakness. He did not see a physician at that time, and was only brought in at his family’s insistence. He reports he does feel confused but cannot elaborate any more. He denies headache, neck pain, or photophobia. Radiologic scans of his brain are done. Describe the scans.

7. Question 2
What is your differential at this time?

8. Answer Toxoplasmosis Lymphoma Aspergilloma Candidiasis Tuberculosis
Bacterial abscess
Cryptococcus
JC/PML
High grade glioma

9. Question 4
To confirm the brain mass etiology, a stereotactic biopsy was performed. Describe the intraoperative smear. What is your diagnosis? Click here to view slide.

10. Question 5
The next day you receive a permanent section of the biopsy. Describe what you see. Does it correlate with the intraoperative smear? Click here to view slide.

11. Question 6
What additional test can the neuropathologist order on this tissue that will absolutely confirm the diagnosis?

12. Answer
A Toxoplasma gondii immunostain

13. Question 7
The Toxoplasma gondii immunostain arrives. Is it positive? Where is the positivity? Click here to view slide.

14. Question 8
What is the reservoir of T. gondii?  How is it usually acquired, and in what tissue(s) does it normally reside?