Adult-onset leukoencephalopathy with brain stem and spinal cord involvement in Chinese Han population: a case report and literature review.

Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a recently described disorder with an autosomal recessive mode of inheritance. We report a case of rare adult-onset LBSL with typical magnetic resonance imaging (MRI) features. The DARS2 gene mutation analysis has identified a c. 228-20_21delTTinsC (p.R76SfsX5) mutation and a c. 850G > A (p. 284E > K) mutation. With glucocorticosteroid treatment the patient has had improvement in bladder symptoms. This is the first reported adult-onset LBSL case in the Chinese Han population. A review of the literature suggests that brain lactate elevation in adult-onset LBSL is lower than early-onset cases (P < 0.01), and early-onset cases show mild intelligence and cognition decline. These observations suggest that age of onset and brain lactate levels probably influence the prognosis of LBSL.