Acute Disseminated Encephalomyelitis Presenting as Conversion Disorder

SIR: Acute disseminated encephalomyelitis (ADEM) is an uncommon inflammatory demyelinating disease of the central nervous system (CNS). This immune-mediated, inflammatory disease usually occurs after systemic viral or bacterial infection, or vaccination. The signs and symptoms of ADEM consist of various combinations of motor, sensory, visual, gait, and memory disturbances. Some case reports of ADEM presented as psychiatric disorders in the literature. One such reported case is that of acute Korsakoff’s syndrome; other such cases are of acute psychosis.^2,3,4

Conversion disorder, one of the most common psychiatric disorders, is characterized by the presence of one or more neurological symptoms, such as paralysis, blindness, and mutism, which cannot be explained by a known neurological or medical disorder.

We herein report the first case of ADEM, initially diagnosed as conversion disorder.

Case Report

The patient was a 29-year-old, married woman who was brought to the emergency room at Trakya University Hospital due to mutism and contractions in her extremities. Her husband noticed that she looked nervous for a few weeks because she did not menstruate, and she thought that she might be pregnant. She had no significant past psychiatric history, but she caught a cold 2 weeks prior to being brought into the emergency room, which resolved spontaneously within a few days. In the emergency room, thorough physical examination, complete blood count (CBC), biochemical assays, ultrasonography of the abdomen, and cranial computed axial tomography (CT) revealed no pathological findings. On neurological examination, she was awake, partly cooperative, but aphasic. She was ataxic, and she had astasia. On psychiatric evaluation, she was mutistic and agitated, with blunted affection. Because it was not possible to explain the symptoms on the basis of any known neurological or medical disorder, the patient was admitted to the psychiatric inpatient unit with a diagnosis of “conversion disorder.” No medication was administered during follow-up. Her condition remained unchanged while in the psychiatric unit, and evaluation for an underlying medical disorder continued. Electroencephalography (EEG) was normal at admission and at the end of the first week. The patient underwent lumbar puncture 5 days after admission to the psychiatric unit. Cerebral spinal fluid (CSF) contained no cells, 63 mg/dl protein, and the IgG index was 0.38 (normal value was <0.77), without a detectable oligoclonal band. T₂-weighted magnetic resonance imaging (MRI) scan of the brain was performed on day 12 of admission to the psychiatric unit and revealed bilateral multiple areas of increased signal intensity in the periventricular deep white matter, which was suggestive of demyelination. Lesions demonstrated no enhancement with gadolinium. Magnetic resonance imaging findings indicated a diagnosis of ADEM, and the patient was transferred to the Neurology Unit, where her condition improved gradually. She underwent intravenous immunoglobulin therapy for the next 5 days. She was able to walk with help, she had slight spasticity in the upper and lower extremities, her mutism disappeared and her speech was spontaneous and fluent when discharged from hospital.

On a follow-up MRI performed 3 months after symptom onset, the lesions in the periventricular deep white matter did not disappear, which was in contrast to clinical improvement.

Comment

Our patient had ADEM following upper respiratory tract infection. At first, she was admitted to the psychiatric inpatient unit with the diagnosis of conversion disorder because no neurological or medical disorder was detected in the emergency room, and it was thought that there was significant association between the symptom onset and a stressor (suspicion of unexpected pregnancy). We know that symptoms of most patients with conversion disorder resolve in a few days. The symptoms experienced by our patient were still present during the subsequent weeks, and therefore we continued to evaluate her. A diagnosis of ADEM via brain imaging was finally made.

We can conclude that patients must have thorough medical and neurological evaluations at the time of the diagnosis of conversion disorder, even though a stressor is associated with the initiation of the symptoms.