A 33-year-old woman with no past medical history comes to the emergency department complaining of progressive leg weakness and difficulty walking that started 2 days ago. Yesterday she had difficulty with urination. Two weeks ago, she had an upper respiratory tract infection and diarrhea that has since resolved. She is a vegan and takes daily multivitamin supplements. She does not use tobacco, alcohol, or illicit drugs.
Vital signs are within normal limits. Cranial nerve examination is unremarkable. Strength is 5/5 in the upper extremities and 2/5 in the lower extremities. Reflexes are 2+ in the arms but absent in the legs with decreased tone. Rectal tone is diminished. There is no response to plantar cutaneous stimulation in the big toes bilaterally. Superficial abdominal reflexes are absent. There is sensory loss to pain, temperature, vibration, and proprioception of both lower extremities.
Which of the following is the most likely diagnosis?

Question

A 33-year-old woman with no past medical history comes to the emergency department complaining of progressive leg weakness and difficulty walking that started 2 days ago.  Yesterday she had difficulty with urination.  Two weeks ago, she had an upper respiratory tract infection and diarrhea that has since resolved.  She is a vegan and takes daily multivitamin supplements.  She does not use tobacco, alcohol, or illicit drugs.
Vital signs are within normal limits.  Cranial nerve examination is unremarkable.  Strength is 5/5 in the upper extremities and 2/5 in the lower extremities.  Reflexes are 2+ in the arms but absent in the legs with decreased tone.  Rectal tone is diminished.  There is no response to plantar cutaneous stimulation in the big toes bilaterally.  Superficial abdominal reflexes are absent.  There is sensory loss to pain, temperature, vibration, and proprioception of both lower extremities.
Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

This patient's presentation suggests transverse myelitis (TM), a rare inflammatory disorder causing segmental spinal cord injury. Most cases of TM are idiopathic, likely due to an autoimmune process following a viral infection (50% of cases). Patients present initially with spinal shock - lower-extremity weakness, flaccidity, areflexia, and absent Babinski sign. There will be a sensory level to all primary sensory modalities. Bowel and bladder dysfunction are present. Some patients also complain of a "band-like" squeezing pain. After 1 week, patients usually develop spasticity, hyperreflexia, Babinski sign, and clonus. Diagnosis is suggested by magnetic resonance imaging with contrast, which shows enhancing cord segments with surrounding edema. Cerebrospinal fluid analysis usually shows elevated protein, moderate lymphocytosis, normal glucose, and no oligoclonal bands. Treatment is typically supportive (physical therapy). Intravenous corticosteroids can sometimes help patients with an autoimmune component of the disease. Recovery usually occurs within 3 months, with up to 40% of patients experiencing some residual disability. (Choice A) Cauda equina syndrome affects the lumbosacral roots as they exit the spinal cord and is usually caused by a herniated disk or tumor. Clinically, patients will present with severe unilateral pain in the saddle region that radiates down to the legs with associated asymmetrical lower-extremity weakness (proximal and distal). The presence of significant bowel/bladder/sphincter symptoms clinically distinguishes cauda equina syndrome from Guillain-Barré syndrome (GBS); the presence of severe shooting (lancinating) pain distinguishes it from TM. Cauda equina syndrome (Choice B) TM can mimic GBS in the setting of spinal shock, as reflexes and Babinski sign will be absent. However, patients with GBS will not have bowel/bladder symptoms or a sensory loss below a spinal cord segment. (Choice C) Spinal cord infarction usually presents with abrupt onset (minutes to hours) of back pain, weakness (and possibly paralysis), loss of sensation and reflexes, and autonomic dysfunction. Onset of symptoms (days) and antecedent viral illness are more suggestive of TM. (Choice D) Vitamin B12 deficiency results in slowly progressive weakness, ataxia, and neuropsychiatric disturbances. This patient's acute onset of symptoms is less consistent with cobalamin deficiency. Educational objective: Acute onset of weakness and sensory loss below a segmental spinal level, paresthesias, and bowel/bladder/sphincter dysfunction suggest transverse myelitis. Magnetic resonance imaging with contrast shows enhancing cord segments with surrounding edema. Treatment is mainly supportive and can include intravenous corticosteroids. __________ References: Transverse myelitis. (http://www.ncbi.nlm.nih.gov/pubmed/23186897)

A 33-Year-Old Woman with No Past Medical History Comes to the Emergency