Diffuse Encephalitis Diagnosed on PET/CT Acquired in a Patient in Status Epilepticus with Negative...
-
Upload
ralf-roy-knight -
Category
Documents
-
view
212 -
download
0
Transcript of Diffuse Encephalitis Diagnosed on PET/CT Acquired in a Patient in Status Epilepticus with Negative...
Diffuse Encephalitis Diagnosed on PET/CT Acquired in a Patient in Status Epilepticus
with Negative MRI
J Cain1,2, J Hill2, C Coutinho2, S Mathur2 1University of Manchester, Manchester, UK, 2Lancashire Teaching Hospitals, Preston, UK
Excerpta Extraordinaire EE-03
Purpose
• To describe a case of encephalitis diagnosed on PETCT performed in a ventilated patient.
• The patient had previous and subsequent MRI within normal limits.
Case Report
• 23 year old previously well female presented with seizures, reduced GCS, left sided neglect and left focal motor seizures.
• A focal abnormality was identified in temporal region on EEG.
• Patient entered prolonged period of status epilepticus.
• Seizures not controlled with quadruple anticonvulsants.
• Intubated and ventilated on ICU.
Imaging Findings
• PET/CT (FDG) – • Diffuse reduced tracer uptake (hypo-metabolism) in
posterior frontal, temporal, occipital and parietal lobes bilaterally, with relative sparing of the anterior frontal lobes and posterior fossa.
Raw axial PET
Imaging Findings
• Follow up MRI 1 month after presentation:• No focal signal abnormities, However there is moderate generalised
atrophy which seem to have been progressive.
Axial T2
SagittalT1Coronal FLAIR
Imaging Findings • Follow up MRI 4 months after presentation:• No focal signal abnormities, No obvious cortical abnormalities.
Less pronounced atrophic changes compared to previous exam.
AxialT2
Coronal FLAIR
LP findings
• Diagnosed with anti MNDA receptor encephalitis on CSF analysis.
• The remainder of the full body PETCT was within normal limits.
• No underlying malignancy identified.
Anti MNDA receptor encephalitis
• Discovered in 2005• Antibodies against NR1–NR2 heteromers of the NMDA receptor.• Progressive illness presents with psychosis, memory deficits, seizures,
and language disintegration. • Later features coma, catatonic, abnormal movements, autonomic and
breathing instability.• The disorder predominantly affects adolescents and young adults
mean 23 , 7 to 1 F>M.• Responds well to treatment but can relapse. • High incidence of underlying tumour (e.g. ovarian teratoma)• >75% of patients have substantial recovery that occurs in inverse order
of symptom development associated with a decline of antibody titres.
Patient Outcome
• Patient made good recovery on immune modulating therapy.
• Discharged home.• Slight persistent cognitive impairment.• No associated malignancy was identified.
Summary
• PET/CT is able to detect hypo-metabolism in encephalitis even in the presence of normal MRI imaging.
• The case demonstrates a possible role of performing PETCT in such patients.
• The technical difficulties of performing a PET CT in a ventilated patient are less onerous than performing a MRI.
References
• Mohr, Brandt C., and Satoshi Minoshima. "F-18 fluorodeoxyglucose PET/CT findings in a case of anti- NMDA receptor encephalitis." Clinical nuclear medicine 35, no. 6 (2010): 461-463.
• Dalmau, J; Lancaster, E; Martinez-Hernandez, E; Rosenfeld, MR; Balice-Gordon, R "Clinical experience and laboratory investigations in patients with anti-NMDAR encephalitis.” The Lancet. Neurology 10 2011(1): 63–74