Reversible splenial lesion syndrome associated with encephalitis/encephalopathy presenting with great clinical heterogeneity

A 23-year-old man with the complaints of fever for 6 days, disturbance of consciousness for 4 h was admitted to the hospital on March 14, 2012. The patient initially presented with cold symptoms including fever, nasal congestion, and pharyngalgia 6 days ago. At the day of admission, he had temperature up to 39 °C, severe headache, and vomiting. He suddenly lost consciousness and experienced a seizure at that night. The symptom of seizure completely stopped after 2–3 min, but coma was persistent. Physical examination on admission revealed comatose state (Glasgow Coma Scale, GCS: 7), cyanosis, stiff neck, and no voluntary movements. The emergent therapy included mechanical ventilation, antiviral (acyclovir), and antibiotics (cefoperazone). At 1 day after admission, he can detach from the ventilator, but still was in comatose state. Cerebral MRI revealed an isolated lesion in the splenium of corpus callosum with slight hyperintense on T2 weighted images (T2WI), slight hypointense on T1 weighted images (T1WI), no enhancement on contrast images, obvious hyperintense on diffusion weighted imaging (DWI) (Fig. 1a), and decreased apparent diffusion coefficient (ADC) values (Fig. 1b). Fractional anisotropy map revealed mildly decreased value of SCC lesion (Fig. 1c), but with normally projecting direction of white matter fibers (Fig. 1f). At 4 days after admission, the patient experienced several seizures again, and became deep comatose (GCS: 5). The patient was administrated with carbamazepine (400 mg/d), methylprednisolone (1000 mg/d), and intravenous immunoglobulin (IVIG) (2 g/kg). The symptoms of seizure gradually disappeared, and the temperature returned to normal limits, while disturbance of consciousness was persistent. Laboratory examination revealed serum chemistry, blood routine, thyroid function, serum ammonia, tumor biomarkers, extractable nuclei antigen (ENA) polypeptide spectrum, and anti-neutrophil cytoplasmic antibody (ANCA) were normal. A lumbar puncture revealed a mild lymphocytic pleocytosis (20 cells/μL) with normal protein and glucose contents. Oligoclonal bands were negative in serum and CSF. The quantity of myelin basic protein (MBP) was 3.8ug/L (normal <4ug/L) in CSF. Intrathecal IgG synthesis rate was 0.55 mg/24 h (normal <0.7 mg/24 h). The etiological procedure found a positive PCR for influenza A in nasopharyngeal swabs, while other extensive microbiological workups were negative. At 17 days after admission, second MRI showed the abnormalities of SCC nearly disappeared on DWI (Fig. 1d) and ADC (Fig. 1e). Spinal cord MRI was normal. At 45 days, he was transferred back to local hospital for nursing care. After 1 year follow-up, the patient was in vegetative state, nasogastric tube feeding, and bedridden.

A 16-year-old boy with the complaints of fever and headache for 5 days, delirious behaviors for 3 days, and consciousness disturbance for 1 day was admitted to the hospital on February 12, 2014. The boy initially had fever, cough, and headache. After 3 days, the patient presented with severe headache, vomiting, and irritability, so antiviral drug (acyclovir) was administrated. After 4 days, he had consciousness disturbance, but no seizures were observed in the disease course. Physical examination on admission revealed comatose state (GCS: 8), slight limb movements responsive to pain stimulus, and negativity of bilateral pathological reflex. On admission, cerebral MRI showed an isolated lesion in the central SCC with slight hyperintense on T2WI (Fig. 2a), slight hypointense on T1WI (Fig. 2b), hyperintense on DWI (Fig. 2c), and apparent decreased ADC values (Fig. 2d). A lumbar puncture revealed a mild elevation of cell counting (15 cells/uL) with normal protein and glucose content. Oligoclonal bands were negative in serum and CSF. The quantity of MBP was 3.3ug/L in CSF. Intrathecal IgG synthesis rate was 0.61 mg/24 h. Laboratory examination revealed serum chemistry, thyroid function, serum ammonia, tumor biomarkers, ENA polypeptide spectrum, and ANCA were normal. At 1 day after admission, patients experienced more severe disturbance of consciousness, low blood pressure (70/50 mmHg), and breathing difficulty with hypoxemia and acidosis, so mechanical ventilation was administrated immediately. Meanwhile, the patient was administrated with methylprednisolone (1000 mg/d), IVIG (2 g/kg), antiviral (acyclovir), and antibiotics (vancomycin). At 10 days after admission, the patient had stable vital signs, while he was still in comatose state. At 32 days after admission, second MRI showed abnormal signals of the SCC completely disappearing on T2WI (Fig. 2e), T1WI (Fig. 2f), DWI (Fig. 2g) and ADC (Fig. 2h). After 7 months follow-up, the patient was in a condition of agrypnocoma, nasogastric tube feeding, and bedridden.

This study was approved by the ethics committee of the First Affiliated Hospital of Nanchang University.

Written consent for publication had obtained from patients or their parents.