Case report of leukoencephalopathy with predominant brainstem and spinal cord involvement and lactate elevation behind the mask of multiple sclerosis

Abstract

Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a rare or underdiagnosed autosomal-recessive mitochondrial disease that sometimes mimics progressive multiple sclerosis (MS). Difficulties in diagnosing LBSL are due to the possibility of the onset of the disease in adulthood, and the nonspecific clinical picture in the form of slowly progressive neurological symptoms (pyramidal, cerebellar, sensory and cognitive impairments) without the involvement of other organs and systems characteristic of mitochondrial pathology. However, a notable feature of LBSL is its pathognomonic magnetic resonance imaging of the white matter of the brain and spinal cord, which allows a reliable diagnosis when certain criteria are met. Currently, there are no drugs registered for the specific treatment of LBSL, however, correct diagnosis is necessary to complete the epidemiological data, and to prevent the prescription of drugs with side effects that worsen the quality of life of patients. The number of clinical publications about LBSL is small, both in Russian and foreign publications, and therefore each identified case is of great interest. The article presents a brief review of the literature and a case report of a patient with the adult-onset LBSL, who received disease modifying therapy of multiple sclerosis for a long time. The patient’s main problems were progressive lower paraparesis and ataxia. To make clinicians more aware, we have reviewed the difficulties in differential diagnosis between LBSL and MS, we provided detailed medical history, neurological status, and magnetic resonance imaging findings.