Clinical and Genetic Analysis of Retinitis Pigmentosa with Primary Angle Closure Glaucoma in the Chinese Population

Retinitis pigmentosa (RP) constitutes a class of common inherited retinal dystrophies. Patients with RP and comorbid primary angle-closure glaucoma (PACG) have been described, but the relationship between the diseases remains unclear. This study investigated the clinical and genetic characteristics of Chinese patients with RP and comorbid PACG. Of 1356 patients with RP, we analyzed the genetic features of 39 RP patients with PACG using next-generation sequencing and reviewed their clinical characteristics. In total, 18 patients with acute PACG and 21 patients with chronic PACG were included in this study; their age at examination was 50.54 ± 12.99 years (range, 25.0–71.0 years), and their age at PACG onset was 46.04 ± 14.50 years (range, 24.9–68.0 years). Additionally, the mean lens thickness (LT) was 4.49 ± 0.44 μm, and the mean axial length (AL) was 22.63 ± 1.17 mm. Notably, the prevalence of PACG in patients with RP was 2.88%; this was higher than the prevalence in the general population. This could be explained by nanophthalmos, thickened lentis, ectopia lentis, or zonular insufficiency. Furthermore, patients with a shorter AL, a greater LT, iridociliary cysts, or nanophthalmos exhibited earlier development of PACG. Overall, 30 disease-causing variants spanning 17 genes were identified in 56.41% of the patients, and <i>PRPH2</i> was the most common mutation gene. Our findings revealed that there is a strong association between RP and PACG. Furthermore, intraocular pressure (IOP) should be measured in patients with RP to protect them from the aggravated damage of an elevated IOP.

色素性视网膜炎（Retinitis pigmentosa, RP）属于一类常见的遗传性视网膜退行性疾病。临床中曾有色素性视网膜炎合并原发性闭角型青光眼（primary angle-closure glaucoma, PACG）患者的报道，但二者之间的关联机制尚未明确。本研究针对中国人群中合并原发性闭角型青光眼的色素性视网膜炎患者的临床与遗传学特征展开探究。本研究纳入1356例色素性视网膜炎患者，对其中39例合并原发性闭角型青光眼的患者采用下一代测序（next-generation sequencing, NGS）技术分析其遗传学特征，并回顾性整理其临床资料。本研究共纳入18例急性原发性闭角型青光眼患者与21例慢性原发性闭角型青光眼患者，患者就诊时年龄为50.54±12.99岁（范围：25.0~71.0岁），原发性闭角型青光眼发病年龄为46.04±14.50岁（范围：24.9~68.0岁）。此外，患者平均晶状体厚度（lens thickness, LT）为4.49±0.44μm，平均眼轴长度（axial length, AL）为22.63±1.17mm。值得注意的是，色素性视网膜炎患者中原发性闭角型青光眼的患病率为2.88%，高于普通人群的患病率。该现象可通过小眼球、晶状体增厚、晶状体异位或悬韧带功能不全予以解释。进一步分析显示，眼轴更短、晶状体更厚、存在虹膜睫状体囊肿或合并小眼球的患者，其原发性闭角型青光眼发病更早。总体而言，56.41%的患者中共检出覆盖17个基因的30个致病性变异，其中PRPH2为最常见的突变基因。本研究结果证实色素性视网膜炎与原发性闭角型青光眼之间存在显著关联。临床中应对色素性视网膜炎患者检测眼压（intraocular pressure, IOP），以避免眼压升高加重眼部损伤。