Case 1 history, examination
In 2013 30 years old male patient developed a right calf muscle crampy.
Already in 2014 patient developed right leg weakness, fasciculations in
right leg muscles, shin atrophy, right foot drop. At that time the
neurological examination revealed the muscle strength in the left limbs
5/5 points, in the right limbs 5/5 points, except for the extensors of
the foot — where it was 2/5 points; amyotrophy of the right shin
muscles, the absence of sensation disturbances (Fig.1). Disease
progression was slow and in 2015 amyotrophy involved right thigh
muscles. By the end of 2015, the patient developed fasciculations
throughout the body, painful cramps and muscle weakness in the left
shin. During this time, the examination revealed brisk knee reflexes,
the Babinsky sign on the right side. In 2016 patient developed left leg
amyotrophy, in 2017 left foot drop. In 2018 weakness involved left thigh
and upper extremities.
The patient was observed in dynamics and in 2019 neurological assessment
revealed restricted movements mostly in lower limbs, excessive
amyotrophy of the right and left legs, but no observable amyotrophy of
the upper limbs (Fig.2). Generalized fasciculations were noted. Motor
examination showed excessive muscle weakness of the lower limbs more
pronounced in distal part, and mild weakness of the upper limbs. Deep
tendon reflexes were brisk with wide spread, pathological signs on upper
limbs, Achilles reflex and Babinsky sign absent on both sides. Sensation
to pinprick, vibration and proprioception were normal. There were no
speech, swallowing, and breathe disturbances.
During the disease course the patient underwent MRI and EMG. In 2015 MRI
of the spinal cord showed slit-like syrinx cavity and looking as dilated
central canal of the thoracic spinal cord at the ThIII - ThIX vertebrae
level, no Chiari malformation or other extramedullary factors
predisposing to syringomyelia (Fig.3). MRI of the brain showed no
pathology. In 2015 EMG showed signs of damage to the lower motor neurons
of the of the lumbar and cervic spinal cord (both motor unit remodeling
and denervation), and no conduction blocks. In 2016 EMG showed the
negative trend of damage. Follow-up imaging in both 2016 and 2019 showed
no significant changes in cavity size (Fig.4). Also the patient was
tested for the titer of GM-1 and GM-2 antibodies (markers of multifocal
motor neuropathy), which was low. Other laboratory tests of blood and
CSF were normal.