Opsoclonus-Myoclonus Syndrome in Children and Adolescents: A Therapeutic Challenge

Abstract

Opsoclonus-myoclonus syndrome (OMS) is a neurological non-fatal disease that usually responds to immunotherapies. However, the real challenge is to counteract the high frequency of relapses and long-term developmental sequelae. Since the OMS is extremely rare, a common consensus regarding therapeutic guidelines is still lacking. The goals of this study were to test whether ACTH was superior to other immunotherapies and to investigate whether an early treatment could improve the outcome. Sixteen children affected by OMS were retrospectively reviewed. Eight children had a neuroblastic tumor. The other eight patients were affected by non-paraneoplastic OMS. Overall, the most commonly used treatment was corticotherapy (n = 11). However, ACTH (n = 10), rituximab (n = 7), immunoglobulins (n = 4), cyclophosphamide (n = 3), and mycophenolate (n = 2) were also administered. ACTH was associated with a high percentage of patients who healed (80%) and, as a first-line therapy, was associated with a lower incidence of relapses. An early treatment was associated with a favorable long-term outcome. Long-term sequelae occurred in 42% of patients who were treated early and in all of those who were treated late. It is advisable for the affected children to be identified at an early time, as they may benefit from an early treatment. ACTH represents an effective treatment with a high probability of recovery and low rate of relapses.

Review of Opsoclonus-Myoclonus Ataxia Syndrome in Pediatric Patients

“…However, early treatment is indicated and has been shown to be associated with better long-term outcomes [ 53 ]. Mizia-Malarz et al found that long-term sequelae occurred in all patients that were treated late, but only in 42% of patients that were treated early [ 54 ]. In some cases whereby OMAS is associated with neuroblastoma, tumor resection has led to the alleviation of symptoms, but, in others, the symptoms persisted [ 30 , 37 , 55 ].…”

“…In some cases whereby OMAS is associated with neuroblastoma, tumor resection has led to the alleviation of symptoms, but, in others, the symptoms persisted [ 30 , 37 , 55 ]. Adrenocorticotropic hormone (ACTH) [ 54 ], steroid therapies [ 56 , 57 ], and IVIG are commonly used in the treatment of OMAS. A randomized controlled trial of 53 participants demonstrated a significantly superior response in patients who were given a combination of IVIG and prednisolone as compared to prednisolone alone [ 58 ].…”

Paraneoplastic syndromes in childhood neuroblastoma

“…[19] An early diagnosis and treatment correlate with an improved prognosis and a decreased likelihood of neurological or neuropsychiatric complications. [20] Long-term outcomes following OMS in children have shown that patients typically achieve relatively good recovery, albeit incompletely in terms of motor function. [21,22] However, cognitive, and behavioral deficits are often observed, which can significantly impact functioning.…”