TWiP 221: Delusional parasitosis

October 1, 2023

Michelle and Alexander join TWiP to solve their case of the 36 Year Old Male with shortness of breath, stinging pain in the extremities, fatigue, abdominal cramps, and bowel irregularities, and discuss host cell invasion by Trypanosoma cruzi.

Hosts: Vincent Racaniello, Dickson Despommier, Daniel Griffin, and Christina Naula

Guests: Michelle Naegeli and Alexander Grieb

Click arrow to play Download TWiP #221 (60 MB .mp3, 83 minutes)

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Case Study for TWiP 221

This is the case of a  man in his 50s, with no remarkable prior medical history, who received care at a hospital in northern California, USA, after experiencing a generalized seizure. Magnetic resonance imaging (MRI) demonstrated a solitary left temporal lobe T2 hyperintensity with gadolinium rim enhancement and surrounding edema. After receiving treatment with dexamethasone and levetiracetam, he was transferred to an academic medical center.

Examination by neurology consultants noted disorientation, inattention, moderate aphasia (difficulty communicating), and mild right hemiparesis. Cerebrospinal fluid (CSF) testing revealed increased nucleated cells up to 80/UL (60% lymphocytes, 17% neutrophils, 23% monocytes), protein concentration 38 mg/dL, and glucose concentration 100 mg/dL. 

They proceed to do a brain biopsy from the left temporal lobe lesion with cultures from the brain biopsy sample that did not grow bacteria, fungi, or mycobacteria. They performed metagenomic next-generation sequencing (mNGS) on a CSF sample and sent brain biopsy samples for universal broad-range PCR amplicon sequencing (uPCR) for bacteria, fungi, Mycobacterium tuberculosis, and nontuberculous mycobacteria. which is preliminarily reported as showing well-formed granulomata with acute inflammation. Rereview of neuropathology raised concern for certain round infectious forms that are about 50um in size with some surrounding clearing and a dark area within these forms.

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Music by Ronald Jenkees

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