Liu Yingna, Chen Alexander S, Kamphaengkham Siripim, Leenasirimakul Prattana, Jirawison Choeng, Ausayakhun Somsanguan, Margolis Todd P, Keenan Jeremy D
Harvard Medical School, Boston, Massachusetts, United States of America.
Francis I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America.
PLoS One. 2016 Oct 27;11(10):e0165564. doi: 10.1371/journal.pone.0165564. eCollection 2016.
Cytomegalovirus (CMV) retinitis remains a leading cause of blindness in countries with a high burden of AIDS. Although dilated fundus examinations are recommended for those with CD4 counts below 100 cells/μL, in practice only those with poor vision and/or symptoms are routinely referred for screening. Therefore, the predictive value of this common practice should be assessed.
This is a prospective cross-sectional study. Patients with known HIV and a CD4 count of less than 100 cells/μL attending an HIV clinic in Chiang Mai, Thailand completed a standardized questionnaire about visual symptoms and underwent visual acuity testing and dilated fundus examination. Participants without CMV retinitis were invited for repeated examinations every 3 months until their CD4 count exceeded 100 cells/μL. Patient-level statistical analyses were conducted to calculate diagnostic test characteristics, with bootstrapping to account for correlated data.
Of 103 study participants, 16 had CMV retinitis diagnosed at some point during the study. Participants with CMV retinitis were more likely to complain of visual symptoms compared to those without CMV retinitis (p = 0.01), including scotoma (p = 0.0002), itchy or watery eyes (p < 0.0001), and eye pain (p = 0.003); they were also more likely to have visual acuity worse than Counting Fingers (p = 0.0003). However, the absence of eye symptoms and the absence of poor vision did not strongly affect the probability that a patient did not have disease (negative likelihood ratio 0.56 and 0.76, respectively).
Ocular symptoms and poor visual acuity were poor diagnostic indicators for the presence of CMV retinitis. Systematic screening of HIV patients with CD4 counts below 100 cells/μl should be carried out to detect disease at an early stage, when blindness can still be prevented.
在艾滋病负担较重的国家，巨细胞病毒（CMV）视网膜炎仍然是导致失明的主要原因。尽管建议对CD4细胞计数低于100个/微升的患者进行散瞳眼底检查，但实际上只有视力差和/或有症状的患者才会被常规转诊进行筛查。因此，应评估这种常见做法的预测价值。
这是一项前瞻性横断面研究。在泰国清迈一家艾滋病诊所就诊的已知感染HIV且CD4细胞计数低于100个/微升的患者，完成了一份关于视觉症状的标准化问卷，并接受了视力测试和散瞳眼底检查。没有CMV视网膜炎的参与者每3个月被邀请进行重复检查，直到他们的CD4细胞计数超过100个/微升。进行患者层面的统计分析以计算诊断测试特征，并采用自抽样法处理相关数据。
在103名研究参与者中，有16人在研究期间的某个时间点被诊断为CMV视网膜炎。与没有CMV视网膜炎的参与者相比，患有CMV视网膜炎的参与者更有可能抱怨视觉症状（p = 0.01），包括暗点（p = 0.0002）、眼睛瘙痒或流泪（p < 0.0001）以及眼痛（p = 0.003）；他们的视力也更有可能比数指差（p = 0.0003）。然而，没有眼部症状和视力不差对患者没有疾病的概率影响不大（阴性似然比分别为0.56和0.76）。
眼部症状和视力差是CMV视网膜炎存在与否的不良诊断指标。对于CD4细胞计数低于100个/微升的HIV患者，应进行系统筛查，以便在仍可预防失明的早期阶段发现疾病。
