Effective relapse prevention with monthly intravenous immunoglobulin therapy in a pediatric patient with anti-neutral glycolipid antibody-positive Encephalomyeloradiculoneuropathy

Encephalomyeloradiculoneuropathy (EMRN), a rare autoimmune disorder characterized by both central and peripheral neuropathy, is diagnosed by the detection of anti-neutral glycolipid antibodies in the serum and cerebrospinal fluid. Despite growing recognition, management strategies particularly for relapse prevention in children, remain unclear. A 6-year-old girl who was initially admitted to a local hospital for aseptic meningitis, was transferred to our hospital following rapid deterioration with altered consciousness and hypertension. Electroencephalography revealed diffuse high-amplitude slow waves and gadolinium-enhanced MRI showed contrast enhancement in the meninges of the brainstem and lumbar spinal cord. Based on the clinical course, autoimmune encephalitis was suspected, and methylprednisolone pulse therapy along with plasma exchange was administered. Although muscle weakness and loss of tendon reflexes were observed during the course of treatment, all symptoms completely resolved. Anti-lactosylceramide (LacCer), an anti-neutral glycolipid antibody, was detected in the serum and cerebrospinal fluid in the acute phase. However, because the antibody persisted in the convalescent serum and cerebrospinal fluid, regular immunoglobulin therapy was initiated. Fourteen months after treatment initiation, the antibodies disappeared from the cerebrospinal fluid and no clinical recurrence was observed. This case highlights the effectiveness of intravenous immunoglobulin therapy in preventing the recurrence of pediatric EMRN, even in the presence of persistent antibodies. Further studies are needed to establish a definitive therapeutic strategy for preventing disease recurrence.