Letters to the Editor
Conversion Disorder in a Patient With Diffuse Axonal Injury
Dear Editor:
Diffuse axonal injury (DAI) results from traumatic brain injury (TBI) and particularly from head acceleration or rotational force (1). Magnetic resonance imaging, single photon emission computed tomography, and positron emission tomography are more sensitive for DAI than CT scan, but they are generally not available for diagnosis of acute TBI. Thus, DAI is largely a clinical diagnosis in patients presenting with such an injury. These patients demonstrate cognitive and behavioural symptoms of frontal lobe pathology, such as reduced attention, emotional distance, psychomotor slowing, disinhibition, aggressivity, unrealistic judgment, communication disorder, and impaired executive functioning (1). We describe a case of conversion disorder in a patient with DAI.
Mr A, aged 29 years, presented with a closed head injury following motor vehicle accident. On scene, the patient had a Glascow Coma Scale score of 3 that rapidly improved to 15. Nonetheless, he continued to have paucity of speech, to respond inappropriately, and to preseverate. He demonstrated spontaneous movement in all limbs but was unable to sit up or walk.
Neurological testing was inconsistent. Mr A showed a protective response on provocative testing, pointing away from an organic cause. However, pain testing failed to elicit a response, and he had a left-facial paralysis. Investigations, including 2 head CT scans, were apparently normal.
The team diagnosed mild DAI on the basis of the frontal lobe pathology demonstrated by the patient’s reduced attention and communication deficits. Treatment comprised seizure and anticoagulation prophylaxis with dilantin and heparin, respectively. The patient received physiotherapy and speech– language therapy.
However, the extent of the patient’s cognitive and motor dysfunction could not be explained by mild DAI alone and suggested psychiatric comorbidity. Information obtained from his brother was remarkable for significant psychosocial stressors. A refugee for 1 year, the patient had left his birth country because of threats to his safety. He was recently divorced, and he was under financial pressure.
The psychiatric functional inquiry was negative for substance or alcohol abuse, suicidal and homicidal ideation, mood and anxiety disorders, psychosis, delirium, and dementia. Mr A had suffered what appeared to be a dissociative episode 10 years earlier. There were no apparent medical, personal psychiatric, or family psychiatric histories. There was no obvious motivation for malingering.
The team ultimately concluded that Mr A met DSM-IV criteria for conversion disorder. He had multiple and significant stressors in his life over the course of 1 year and subsequently presented to us with vague neurologic findings that affected both motor and sensory function. The neurosurgical team could not offer a diagnosis to explain all his symptoms.
At 3-week follow-up, he showed minimal improvement. His behaviour was childlike and largely nonverbal, and he was not walking. The persistence and severity of these symptoms indicates that the underlying DAI pathology is more severe than once thought. This case demonstrates the difficulty encountered in diagnosing conversion disorder in the context of pathology that is not detectable with imaging, such as DAI.
Reference
1. Wallesch CW, Curio N, Galazky I, Jost S, Synowitz H. The Neuropsychology of blunt head injury in the early postacute stage: effects of focal lesions and diffuse axonal injury. J Neurotrauma 2001;18:11–20.
Shree Bhalerao, BSc, BA, Pgd, MD, FRCPC
Moumita Barua, BSc
Toronto, Ontario
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