Background and Aims

Demyelinating diseases are characterised by damage to the myelin sheath, resulting in neurological problems.The most common demyelinating diseases are multiple sclerosis, acute disseminated encephalitis, neuromyelitis optica, and other autoimmune encephalitis.

A 37-year-old woman was referred to Neurology for vertiginous syndrome, headaches, paraesthesia and difficulty in ambulation. Otorhinolaryngology ruled out the aetiology of her speciality.

Methods

Several imaging tests (cranial and spinal MRI) were carried out; cerebrospinal fluid (CSF) análisys and microbiological culture; search for autoantibodies: antinuclear, anti-ENA, anti-DNAds, anti-Scl70, anti-Jo1, anti-LKM, anti-mitochondrial and anti-smooth muscle antibodies; intracellular anti-neuronal antibodies (Hu, Yo, Ri, CV2, Ma2, Amphiphysin, Tr) and anti-GAD antibodies.

All these tests and determinations were repeated over 4 years, with unchanged results. Finally, in the last year, the determination of Ac against neuronal surface receptors (anti-NMDAr, AMPAr, GABAr B, LGI1, CASPR-2, DPPX), and anti-neuronal Ac related to demyelination (AQP4 and MOG) was performed.

Results

All serum and CSF antibody studies initially studied were normal or negative.

However, the anti-neuronal antibodies related to demyelination were positive for anti-MOG antibodies at medium titre.

With the results obtained, a diagnosis of autoimmune encephalomyelitis with demyelination by anti-MOG antibodies was made.

Conclusions

The differential diagnosis of demyelinating diseases is complex, as clinical manifestations may be similar and imaging and laboratory tests are not completely specific.
In a group of demyelinating diseases of the central nervous system including acute disseminated encephalitis and autoimmune demyelinating encephalomyelitis anti-MOG is produced. For their determination, indirect immunofluorescence is performed on MOG-transfected HEK cells and their determination is a very useful diagnostic tool.