Letter to the Editor

Iran J Public Health, Vol. 50, No.1, Jan 2021, pp.203-204

A Case Report of Non-Herpetic Limbic Encephalitis with Psychological Symptoms and Parkinsonism*George IMATAKA, Shigemi YOSHIHARA
Department of Pediatrics, Dokkyo Medical University, Tochigi, Japan*Corresponding Author: Email: geo@dokkyomed.ac.jp(Received 05 Apr 2020; accepted 19 Apr 2020)

Dear Editor-in-Chief
Simple herpetic and non-herpetic limbic encephalitis (NHLE) are known causes of limbic
encephalitis. The age of onset of NHLE is higher
among young women (1). Moreover, NHLE isassociated with the development of malformative
teratomas in the abdominal cavity. The clinicalcourse is varied with symptoms such as hallucinations, visual delusions, and dementia-like symptoms (1).
Here, we report a case of a young female patientwith NHLE without teratoma who developed
parkinsonism with psychiatric symptoms as theinitial symptoms of her clinical course.
A 14-yr-old girl was hospitalized due to involuntary movements of her left arm and emotional
instability and informed consent was obtained
from parents. She had no prior disease historywhen we first showed signs of emotional instability and developed low-grade fever for a month

before hospitalization. She abused her parents 3days before admission, and had fever and shortterm impairment of consciousness in the time ofadmission. During the routine physical examination, she showed noticeable sweating, especiallyon her hands. A few days later, she developed afever and was unable to sleep during the night.
Her memory disorder got worse and conversation with her became problematic. She also developed a resting tremor in both hands. In addition, her movements became sluggish and she
was unable to walk normally. Her limbs were stiffand she suffered from severe constipation.
We diagnosed her clinical condition as Parkinsonism. Her handwriting was small and she could
write a continuous line using small letters. Whenshe was asked to draw, she could only generatesmall drawings (Fig. 1).

Fig. 1: Patient’s writing and drawing on the 4th day of admission.

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Imataka & Yoshihara: A Case Report of Non-Herpetic Limbic Encephalitis with …

Results from her blood test on the 3rd day after
her admission revealed WBC count of 1,400/μl,
CRP level of 0.68 mg/dl, and CK level of 872
U/l. Cerebrospinal fluid (CSF) examination
showed a cell count of 4/μl, protein level of 15
mg/dl, and glucose level of 59 mg/dl. CSF neopterin level was 33.35 pmol/ml; biopterin levelwas 11.21 pmol/ml; and the N/B ratio was 2.97.
Anti-NMDA receptor antibody and Anti-GluR
receptors were tested negative. PCR tests for CSF
herpes simplex virus were negative. Brain MRI
revealed no abnormalities and EEG results exhibited no epileptic discharges. Her abdominal
echogram was normal with no evidence of teratoma. On the 5th, brain 18F-fludeoxyglucose positron emission tomography (18F-FDG-PET) revealed an increase in hyper perfusion, predominantly in the right lenticular nucleus (Fig. 2A/B).
Based on her clinical course we diagnosed NHLEand we prescribed methylprednisolone at 1,000
mg/day for 3 days as steroid pulse therapy. Afterthe therapy, her consciousness level improved
over time. After a month, her Parkinsonism hadalmost disappeared and the lenticular nuclear hyper perfusion had improved (Fig. 2C/D). She
was discharged without sequelae 2 months afteradmission.

Fig. 2: Brain 18F-FDG PET on days 5 (A/B) and 30(C/D)

Parkinsonism is characterized by symptoms of
Parkinson’s disease, which can arise from different causes other than the classic disease. Parkinsonism is known to occur due to manganese poi-Available at:

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soning, drug side effects, degenerative diseases ofthe basal ganglia, and viral and post-viral infectious encephalitis (2). Parkinsonism associatedwith NHLE has been rarely reported (3). Ourcase developed limbic encephalitis, possibly following some non-herpetic viral infection. Parkinsonism in this case appeared when brain FDGPET revealed abnormalities in the lenticular nucleus of the basal ganglia. After steroid pulse
treatment, her symptoms as well as findings ofFDG-PET improved. Brain FDG-PET reflects
the metabolic capacity of glucose in the cerebrum. FDG-PET was useful for monitoring themechanism of parkinsonism in this case. Only afew studies have discussed FDG-PET as a useful
tool for the early detection of NHLE (4). Even
though NHLE is a very rare disease, steroid pulse
therapy may be an effective treatment in patientswith parkinsonism and brain FDG-PET investigations may be valuable for assessing its course.

Conflict of interest
The authors declare that there is no conflict ofinterest.

References
1. F Fujiki, Y Tsuboi, K Hashimoto, et al(2004).Non-herpetic Limbic Encephalitis Associated With Relapsing Polychondritis. J
Neurol Neurosurg Psychiatry, 75 (11):1646-7.
2. Tomás R Guilarte, Kalynda K Gonzales (2015).
Manganese-Induced Parkinsonism Is Not Idiopathic Parkinson's Disease: Environmentaland Genetic Evidence. Toxicol Sci, 146 (2):204-12.
3. Matsuzono K, Kurata T, Deguchi S, et al (2013).
Two unique cases with anti-glur antibodypositive encephalitis. Clin Med Insights Case Rep,
6: 113-7.
4. Cózar PS, Sanchez RJ, Sanz RL, Aguilar JB, Ferrer JR (2016). Limbic encephalitis diagnosed
with 18F-FDG PET/CT. Clin Nucl Med, 41(2): e101-3.

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