Department of Pathology, University of Oklahoma Health Sciences Center

NeuroTest Question #8 Next question Previous question

Answer: B (Mycobacteria) Level of difficulty: 1 NeuroTest NeuroLearn NeuroHelp

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Discussion: 

• Pathology of the case: The specimen was obtained from the mass of a thoracic spine. The adipose cells strongly suggest that the specimen is not taken from the brain or spinal cord where mature adipose tissue is not normally found. There are many "globules" of epithelioid cells surrounded by lymphocytes. These structures are known as granuloma and this is a chronic granulomatous inflammation (Panel A). A Langhan's giant cell is present (Panel B). This type of histopathologic changes are seen in mycobacterial infection and also in fungal infection. An acid fast stain on this case revealed scant acid fast positive bacilli consistent with mycobacterial. Bacterial culture results in this case revealed Mycobacteria tuberculerosis.
• Pneumococcus: They usually cause meningitis with or without suppurative changes. They are not associated with chronic granulmatous inflammation.
• Herpes simplex virus: Herpes simplex virus usually affect bilateral temporal lobes. The amount of inflammation can vary from light to intense. Viral inclusions can be seen with routine hematoxyline-eosin stain but are best detected by immunohistochemistry. Granulomatous inflammation is not usually associated with herpes simplex encephalitis. [Click here to see more about Herpes simplex virus encephalitis]
• Rabies: Rabies is a viral encephalitis that is typically associated with a minimal amount of inflammation and Negri body. Granulomatous inflammation is not a usually part of rabies encephalitis. [Click here to see more about rabies] [Click here to see a case]
• Cytomegalovirus: Cytomegalovirus of the central nervous system usually occur as a periventriculitis. Chronic granulomatous inflammation is not a usual part of cytomegalovirus infection. Typical gigantic eosinophilic nuclear inclusions are seen (the so-called "bulls eye"). Cytoplasmic inclusions can also occurs. [Click here to see more about cytomegalovirus infection]

Comment: KarMing-Fung@ouhsc.edu