Baló-like lesion associated with psoriasis and chronic autoimmune thyroiditis

Pathologist Jozsef Balo described a particular form of demyelinating disease, leukoencephalitis periaxialis concentrica, classically named Balo’s concentric sclerosis (BCS). Nowadays, this is defined as a variant of multiple sclerosis. The intensive use of magnetic resonance showed an increasing number of different types of demyelinating lesions. Some of these are specific, but a large variety is under debate regarding the classification. Tumefactive demyelinating lesions (pseudotumoral) can sometimes present a degree of concentricity and can be easily mistaken for a genuine Balo lesion, or at least a Balo-like demyelinating lesion. Historically, the variants of multiple sclerosis were regarded as serious disabling inflammatory damages of the central nervous system, but recent works have demonstrated that the course of the disease may be more variable, at least regarding BCS. Imagistic studies can lead to a better appreciation on the prognosis of BCS and its association with other types of demyelinating lesions [1]. The pathological mechanism behind it still remains a debate, although one can find similarities with multiple sclerosis (MS) and even overlapping lesions of these conditions.