UPMC Eye Center, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
UPMC Eye Center, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
Br J Ophthalmol. 2019 Apr;103(4):499-503. doi: 10.1136/bjophthalmol-2018-312306. Epub 2018 Jun 6.
Central cysts of the iris pigment epithelium, or iris flocculi, are frequently reported in the literature in association with thoracic aortic aneurysm and dissection due to smooth muscle alpha-actin 2 () mutations. Children with mutations may also present with congenital mydriasis. We report our experience regarding the frequency of mutation in children with the above iris anomalies.
This is a retrospective, consecutive case series of all children presenting for iris flocculi or congenital mydriasis at a single tertiary centre from October 2012 to December 2016.
13 children with iris flocculi and 3 with congenital mydriasis presented during the study period. 10 children with iris flocculi completed genetic testing, and none were positive for mutation. All children with congenital mydriasis presented with a multisystem smooth muscle dysfunction syndrome; two of these three children tested positive for missense R179 mutations.
In this series, mutation or copy number variation was not detected in children presenting for iris flocculi, whereas congenital mydriasis was associated with R179 mutation in both cases that tested positive for mutation. The case of congenital mydriasis without typical cardiac features of the R179 phenotype or intracranial vasculopathy was negative for mutation. While all children presenting with these iris anomalies should be offered a genetic evaluation, incidence data should inform genetic counselling, particularly in the absence of a family history of aneurysm or sudden death, or systemic signs of smooth muscle dysfunction.
中央虹膜色素上皮囊肿，又称虹膜絮状物，常与胸主动脉瘤和夹层相关，其发生与平滑肌α-肌动蛋白 2 （）突变有关。携带 突变的儿童也可能出现先天性瞳孔散大。我们报告了在单一三级中心就诊的具有上述虹膜异常的儿童中 突变的频率。
这是一项回顾性、连续的病例系列研究，纳入了 2012 年 10 月至 2016 年 12 月期间在单一三级中心就诊的所有因虹膜絮状物或先天性瞳孔散大的儿童。
研究期间，共有 13 例虹膜絮状物和 3 例先天性瞳孔散大的儿童就诊。10 例虹膜絮状物患儿完成了基因检测，均未发现 突变。所有先天性瞳孔散大的患儿均表现为多系统平滑肌功能障碍综合征；其中 3 例患儿中有 2 例携带 R179 错义突变。
在本系列中，未在因虹膜絮状物就诊的儿童中检测到 突变或拷贝数变异，而先天性瞳孔散大与 2 例阳性患儿的 R179 突变相关。未发现具有典型 R179 表型的心脏特征或颅内血管病变的先天性瞳孔散大患儿的 突变阴性。虽然所有因这些虹膜异常就诊的儿童都应接受基因评估，但发病数据应告知遗传咨询，特别是在无动脉瘤或猝死家族史或无平滑肌功能障碍全身表现的情况下。
