Cognitive and acquired neurodevelopmental deficits have been reported in children with opsoclonus–myoclonus syndrome (OMS) and are known to be associated with more severe and relapsing disease course. However, there is a paucity of data regarding cognitive dysfunction in children with stable neurological disease. We report three children with OMS and evolving cognitive dysfunction in the context of a mild disease course. The children’s ages at disease onset were between 17 and 35 months and they were followed up for 4–10 years. Neuroblastoma was identified in one child. OMS severity scores ranged between 8 and 12/15 at presentation. They underwent immunotherapy and all were in remission by 7 months (range 4–13 months), with treatment maintained for 1 year. One child remained relapse-free, while two others had one clinical relapse each and were immunotherapy-responsive again. In all cases, evolving cognitive dysfunction was reported despite being in remission and stable off treatment for a median of 20 months (range of 12–31 months; two OMS scores of 0/15 and one of 2/15). In children with OMS who have completed treatment and have made full or near full neurological recovery, concerns remain regarding long-term outcome in terms of future learning and cognitive development.

A 10-year-old girl presented with a month long history of episodic limb movements. She had a normal neurological examination and after thorough investigation, she was thought to have possible tics. Anxiety was reported as being a trigger. Unusually, these ‘tics’ were not directly witnessed during hospital visits. Eighteen months after the initial presentation, the clinician observed dystonic posturing after the child stood up from having been seated during a consultation. Paroxysmal kinesigenic dyskinesia (PKD) was then suspected and confirmed on genetic testing. She was successfully treated with carbamazepine. In hindsight, it became apparent that her anxiety was related to a fear of uncontrolled movements, rather than it being a trigger. The abnormal involuntary movements in PKD are precipitated by sudden voluntary movement. Lack of recognition of this typical feature, normal examination and/or features such as coexisting anxiety can lead to misdiagnosis or delayed diagnosis of this easily treatable condition.

The lipodystrophies are an extremely rare group of metabolic conditions which are categorised based on their pathogenesis and phenotype. While primarily known for the striking loss of subcutaneous adipose tissue which they induce, they may also be associated with significant liver injury. In most cases, this results from the secondary deposition of lipid within hepatic parenchyma and is seen predominantly in generalised lipodystrophy. More rarely, patients may develop autoimmune hepatitis. We report a rare case of a 17-month-old boy who developed features of acquired partial lipodystrophy in association with anti-LKM1-positive autoimmune hepatitis following initial presentation with a Henoch-Schönlein purpura-like illness. We describe his challenging path to diagnosis and discuss his ongoing management in an effort to further our understanding of this rare but significant association. This report highlights the need for close clinical observation and a high index of suspicion for recognising early features of lipodystrophy.