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A case of mumps-related acute encephalopathy with biphasic seizures and late reduced diffusion
Kyoko Hazama1, Takashi Shiihara1, Hiroyuki Tsukagoshi2
1Department of Neurology, Gunma Children's Medical Center, 779 Shimohakoda, Hokkitsu-machi, Shibukawa, Gunma 377-8577, Japan.
Background:
Mumps is a common childhood viral disease characterized by fever and swelling of the parotid gland. The prognosis is generally good, although some complications, such as encephalitis (0.1%), exist. Acute encephalopathy with biphasic seizures and late reduced diffusion is the most common type of acute encephalopathy. However, this type of encephalopathy has not been reported in association with mumps infection.
Patient:
A previously healthy 3-year-old Japanese boy had a brief convulsion after fever for 3days, and then had conscious disturbance and parotitis. After several days, he had a second brief convulsion and was admitted. Increased serum amylase levels and presence of anti-mumps immunoglobulin M antibody confirmed mumps parotitis. The patient had another brief seizure later the day of admission. He did not have status or cluster seizures, although the biphasic nature of his seizures, conscious disturbance between the seizures, no pleocytosis in cerebrospinal fluid, and brain magnetic resonance images were consistent with acute encephalopathy with biphasic seizures and late reduced diffusion.
Discussion:
In Japan, the mumps vaccine is not administered as a part of routine immunizations. It thus has low coverage (30-40%), and as a result, mumps infections are still common. However, this is the first case of mumps-related acute encephalopathy with biphasic seizures and late reduced diffusion. This case may be representative of only a minority of patients with mumps-associated central nervous system involvement. Nevertheless, this diagnostic possibility may be considered. In order to prevent mumps-related complications, routine mumps vaccination might be warranted.
Insights
This report details the first case of mumps-related acute encephalopathy with biphasic seizures and late reduced diffusion in a child. This rare neurological complication highlights the need for considering mumps vaccination.
Area of Science:
- Neurology
- Infectious Diseases
- Pediatrics
Background:
- Mumps is a common childhood viral illness, typically benign but can cause complications like encephalitis.
- Acute encephalopathy with biphasic seizures and late reduced diffusion is a known neurological condition.
- This specific type of encephalopathy has not previously been linked to mumps infection.
Observation:
- A 3-year-old boy presented with fever, parotitis, and seizures consistent with mumps.
- He experienced biphasic seizures and conscious disturbance, with MRI findings suggestive of acute encephalopathy with biphasic seizures and late reduced diffusion.
- Diagnostic tests confirmed mumps parotitis, but cerebrospinal fluid showed no pleocytosis.
Findings:
- This is the first documented case of mumps-associated acute encephalopathy with biphasic seizures and late reduced diffusion.
- The case suggests a potential, albeit rare, neurological complication of mumps infection.
- The patient's presentation met criteria for acute encephalopathy with biphasic seizures and late reduced diffusion.
Implications:
- Low mumps vaccination rates in Japan contribute to ongoing mumps infections and potential complications.
- This case expands the spectrum of central nervous system involvement in mumps.
- Routine mumps vaccination may be warranted to prevent such severe neurological sequelae.
