A 16-year-old teenage boy with a history of a germinal testicular tumor presents with short-term memory loss, refractory seizures, and panic reaction.
What is your diagnosis?
A.Herpes simplex encephalitis
B.Drug-induced neurotoxicity
C.Paraneoplastic limbic encephalitis
D.Mesial temporal sclerosis
A
B
?
?
?
The answer is Paraneoplastic Limbic Encephalitis (PLE)
Paraneoplastic limbic encephalitis (PLE) is characterized by a constellation of neuropsychiatric symptoms caused by the effects of a malignant neoplasm located outside the CNS.
These paraneoplastic manifestations are thought to be due to a misdirected, tumor-activated antibody response.
The classic case is a testicular germ cell tumor, as in our patient who was found having an antineuronal antibody against Ma2 (an intracellular antigen).
The classic MRI findings are bilateral/unilateral temporal lobe swelling and FLAIR hyperintensity (A, arrows) with or without mesial temporal atrophy.
With treatment, the signal hyperintensity can return to normal (B, arrows).
The major differential diagnosis is herpes simplex encephalitis, in which a coexisting neoplasm is not present.
中文版;
男性，16歲，既往睪丸生殖細胞腫瘤病史，現表現為短期記憶喪失，頑固性癲癇，驚恐反應
診斷？
A.單純皰疹病毒性腦炎
B.藥物性神經毒性損害
C.副腫瘤性邊緣系統腦炎
D.顳葉內側硬化
診斷：副腫瘤性邊緣系統腦炎
副腫瘤性邊緣系統腦炎（PLE），以中樞神經系統以外的惡性腫瘤引起神經精神症狀為特徵。
這些副腫瘤症狀被認為是由腫瘤錯誤引導、激活的抗體引起的反應性表現。
最經典的原發腫瘤為睪丸生殖細胞腫瘤，正如本病例，患者體內存在抗神經元抗體，對抗Ma2（細胞內抗原）。
典型MRI表現：雙側/單側顳葉腫脹，T2FLAIR呈高信號（A,箭頭），可伴有或不伴有顳葉內側萎縮。
治療後，異常信號區域可恢復正常（B,箭頭）。
主要鑑別診斷為單純皰疹病毒性腦炎，該病不合併腫瘤。
From AJNR Classic Case