Differential diagnosis, investigations and treatment
Subacute progressive extremities weakness with painless visual loss
strongly suggests inflammatory and demyelinating disorders such as
neuromyelitis optica spectrum disorder (NMOSD) or multiple sclerosis
(MS), as well as autoimmune and paraneoplastic syndromes like systemic
lupus erythematosus (SLE), sarcoidosis, or paraneoplastic neurological
disorders. Other considerations include vascular causes (e.g., Susac
syndrome, ischemic optic neuropathy), infectious etiologies (e.g.,
neurosyphilis, HIV), metabolic and toxic causes (e.g., vitamin B12
deficiency, methanol toxicity), and mitochondrial disorders (e.g.,
mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes,
MELAS) Investigations included MRI of the brain and spine with contrast
to evaluate for demyelination, CSF analysis for oligoclonal bands and
inflammatory markers, serological tests for aquaporin-4 (AQP4) and
myelin oligodendrocyte glycoprotein (MOG) antibodies and autoimmune
panels (ANA, dsDNA, ACE, paraneoplastic antibodies)
Cerebrospinal fluid analysis revealed significantly elevated protein and
decreased glucose levels, no white blood cells, positive oligoclonal
bands, mild elevation in lactate dehydrogenase, and negative CSF
cultures for various pathogens. Serum ACE levels were within normal
limits, ESR levels were not elevated, ANA, dsDNA were negative and
screening tests for HIV, syphilis, tuberculosis, and Coccidioides were
negative. Anti- AQP4 and anti-MOG antibodies were also negative.
MRI Brain with and without contrast [Figure 1,2] showed
leptomeningeal enhancements within the intraorbital portion of the right
optic nerve, in the left hypothalamic region, along the left superior
cerebellar hemisphere, along the surface of the cervicomedullary
junction, and along the anterior surface of the pons, without evidence
of abnormal enhancement in the brain parenchyma. MRI C-T-L spine with
and without contrast [Figure 3,4] revealed multifocal nodular
leptomeningeal enhancements along the surface of the cervical cord,
thoracic cord, and along the cauda equina nerve roots, with suspected
intramedullary enhancement associated with leptomeningeal enhancing
lesions at the C6, C7, T1, T4, T7-8, T11, and T12 levels.
The patient was treated with 5 days of IVIG at 0.4 g/kg/day due to a
diagnosis of possible neurosarcoidosis, but his clinical status remained
unchanged after treatment. He was discharged to a rehabilitation
facility.