Objective:

To report a rare case of pemphigus vulgaris complicated by pontine and extrapontine myelinolysis, emphasizing the critical importance of cautious hyponatremia management in autoimmune blistering disorders and the value of multidisciplinary care in preventing severe iatrogenic neurological complications.

Background:

Pemphigus vulgaris is a potentially fatal autoimmune blistering disease characterized by acantholysis and cutaneous-mucosal erosions. Its management requires high-dose immunosuppressants, leading to frequent complications. Hyponatremia is common in severe cases due to fluid loss or SIADH. Rapid sodium correction can provoke osmotic demyelination syndrome, particularly in malnourished or chronically ill patients.

Design/Methods:

A 66-year-old hypertensive woman presented with severe pemphigus vulgaris featuring extensive erosive plaques on the trunk and limbs, with oral and genital involvement. During hospitalization, she developed hospital-acquired pneumonia, steroid-induced diabetes, and severe hyponatremia (112 mEq/L). Hyponatremia was rapidly corrected, triggering neurological deterioration. Brain MRI was performed for diagnosis.

Results:

MRI revealed symmetric T2/FLAIR hyperintensities in the central pons and basal ganglia, confirming extra- and centropontine myelinolysis. The patient received high-dose corticosteroids (1mg/kg initially, increased to 2mg/kg) and L-dopa for movement disorders. Neurological symptoms improved gradually over six weeks. Pemphigus was controlled after three months of immunosuppressive therapy.

Conclusions:

This case highlights myelinolysis as a life-threatening complication of pemphigus management. Hyponatremia correction must be cautious, not exceeding 6-8 mEq/L/24h. MRI is essential for early diagnosis. Multidisciplinary care involving dermatology, neurology, and intensive care is crucial. Rituximab should be considered first-line to minimize corticosteroid-related complications.