The spectrum of coenzyme Q₁₀ (CoQ₁₀) deficiency syndromes comprises a variety of disorders, including a form of autosomal recessive cerebellar ataxia (ARCA2) caused by mutations in the AarF domain–containing kinase 3 gene (ADCK3). Due to the potential response to CoQ₁₀ supplementation, a timely diagnosis is crucial. Herein, we describe two siblings with a novel homozygous ADCK3 variant and an unusual presentation consisting of isolated writer’s cramp with adult-onset. Cerebellar ataxia developed later in the disease course and remained stable during the follow-up. This report highlights that ARCA2 should be considered in the differential diagnosis of familial writer’s cramp.

辅酶 Q ₁₀ (CoQ ₁₀ ) 缺乏综合征包括多种疾病，包括由含有 AarF 结构域的激酶 3 基因 (ADCK3) 突变引起的常染色体隐性小脑性共济失调 ( ARCA2 )。由于补充 CoQ ₁₀可能产生反应，因此及时诊断至关重要。在此，我们描述了两个兄弟姐妹，他们具有一种新颖的纯合ADCK3变异，并且具有一种不寻常的表现，包括成人发病的孤立性作家痉挛。小脑性共济失调在病程后期出现，并在随访期间保持稳定。该报告强调，在家族性写作痉挛的鉴别诊断中应考虑 ARCA2。