Balo concentric sclerosis: scientific review and own observation

Abstract

Balo concentric sclerosis is a rare demyelinating di­sease characterized by the emergence of concentric foci of demyelination as a specific pathomorphological substrate. These foci look like rings on a sawn tree or onion slice with alternating layers of remyelination and demyelination. Pathogenesis of Balo concentric sclerosis probably corresponds to a variant of distal oligodendrocytopathy. There are also suggestions on the hypoxic principle of causality of demyelinating lesions in Balo concentric sclerosis and multiple sclerosis. The true prevalence of Balo concentric sclerosis is unknown, however it is considered that this pathology refers to rare diseases of the nervous system, with a slightly higher prevalence in Asian countries. Most cases of the disease occur at the age of 20–50 years. Semiology has often subacute character, within a few days or weeks. Balo concentric sclerosis usually clinically manifests with severe focal neurological symptoms (pyramidal, cerebellar symptoms, retrobulbar neuritis, cognitive impairment) in combination with general brain symptoms (headache, epileptic syndrome), often with cognitive deficits. Low lymphocytic pleocytosis and normal protein level can be found in cerebrospinal fluid. Also oligoclonal IgG obligatory for multiple sclerosis is detected in 10 % of patients with Balo concentric sclerosis. Concentric rings resembling curls or ‘sawn tree’ on T2- and T1-weighted images with alternating of patterns that are changed and unchanged in the corresponding mode of MR signal refer to the typical MRI characteristics of this pathology. There are only data of IV class evidence in the treatment of Balo concentric sclerosis. The main methods for choosing therapy of this pathology are pulse therapy with glucocorticosteroid drugs, high-volume plasmapheresis or cytostatics (mitoxantrone). The article describes a clinical analysis of diagnostic of this disease in 52-year old man and the conclusion of pathoanatomical section.