目的：了解中国华南地区眼科患者近年术前四项指标的感染状况及阳性患者在不同眼病中的分布。方法：回顾性分析2017年1月-2023年12月在中山大学中山眼科中心进行乙型肝炎表面抗原(hepatitis B surface antigen, HBsAg)、丙型肝炎病毒抗体(hepatitis C virus antibody, 抗-HCV)、梅毒螺旋体抗体(treponema pallidum antibody, 抗-TP)、人类免疫缺陷病毒抗体(human immunodeficiency virus antibody, 抗-HIV)指标筛查的门诊、手术和(或)住院患者资料，并记录和分析患者各项指标的阳性情况。结果：共纳入253 246例患者，HBsAg、抗-HCV、抗-TP和抗-HIV阳性率分别是9.00%、0.45%、1.55%、0.13%。两种或两种以上感染指标阳性的患者共有686例， HBsAg和抗HCV同时阳性的例数最高(57.29%)，其次为抗-HIV和抗-TP(15.74%)。2017-2023年HBsAg阳性率逐年递减，而抗-HCV、抗-HIV、抗-TP阳性率变化不明显。男性的HBsAg、抗-HCV、抗-TP、抗-HIV阳性率均高于女性，差异均有统计学意义(P <0.001)。HBsAg、抗-HCV、抗-TP、抗-HIV阳性率在不同年龄段比较差异均有统计学意义(P <0.001)。在HBsAg、抗-HCV、抗-TP阳性患者中，晶状体病的病例数占比最高，分别为36.72%、39.12%、46.97%。其次是玻璃体/视网膜疾病，占比分别为22.52%、19.65%、19.69%。在抗-HIV阳性患者中，玻璃体/视网膜疾病的病例数占比最高，为42.99%，其次是晶状体病，占26.17%，葡萄膜炎占8.72%。结论：本研究揭示了眼科患者术前四项指标的感染情况及感染患者在不同眼病中的分布，这对于评估眼科手术风险、制定感染控制措施具有重要意义。

Objective: To understand the infection status of four blood-borne pathogens among ophthalmology patients in South China and the distribution of positive patients across different eye diseases. Methods: A retrospective analysis of data from outpatient and inpatient or surgical ophthalmic patients who underwent screening for hepatitis B surface antigen (HBsAg), hepatitis C virus antibody (anti-HCV), treponema pallidum antibody (anti-TP) and human immunodeficiency virus antibody (anti-HIV) at Zhongshan Ophthalmic Center of Sun Yat-sen University from January 2017 to December 2023. The positivity rates of these markers were recorded and analyzed. Results: A total of 253246 patients were included in the study, with positivity rates for HBsAg, anti-HCV, anti-TP, and anti-HIV at 9.00%, 0.45%, 1.55% and 0.13%, respectively. Among these, 686 patients tested positive for two or more markers, with the highest co-positivity observed for HBsAg and anti-HCV (57.29%), followed by anti-HIV and anti-TP (15.74%). The positivity rate of HBsAg showed a yearly decline, while the rates for anti-HCV, anti-HIV, and anti-TP remained relatively stable from 2017 to 2023. Males had significantly higher positivity rates for HBsAg, anti-HCV, anti-TP, and anti-HIV compared to females (P < 0.001). Significant differences in positivity rates for these markers were also observed across different age groups (P < 0.001). In patients with positive HBsAg, anti-HCV, and anti-TP, the proportion of cases with lens diseases were the highest, at 36.72%, 39.12%, and 46.97%, respectively. Vitreoretinal diseases followed, with proportions of 22.52%, 19.65%, and 19.69%, respectively. Among patients with positive anti-HIV, the proportion of cases with vitreoretinal diseases was the highest, at 42.99%, followed by lens diseases at 26.17%, and uveitis at 8.72%. Conclusions: This study reveals the infection status of four blood-borne pathogens in ophthalmology patients and the distribution of infected patients across different eye diseases, which is significant for assessing the risks of ophthalmic surgery and formulating infection control measures.

目的：探讨获得性免疫缺陷综合征（acquired immune deficiency syndrome, AIDS）合并巨细胞病毒性视网膜炎（cytomegalovirus retinitis，CMVR）抗病毒治疗后眼内液特征，为临床优化治疗方案、评估疗效提供参考。方法：回顾性分析2018年11月—2024年12月广州医科大学附属市八医院收治的49例AIDS合并CMVR患者的临床资料，按治疗方式的不同分为全身用药组（n=23，30眼）及联合组（n=26，30眼），全身用药组予静脉滴注膦甲酸钠全身抗病毒治疗，联合组在此基础上加用玻璃体腔注射更昔洛韦，比较两组的眼内液特征。结果：治疗后两组眼内液CMV核酸载量、白细胞介素（interleukin, IL）-6、IL-8、IL-10、血管内皮生长因子（vascular endothelial growth factor, VEGF）、碱性成纤维细胞生长因子（basic fibroblast growth factor，BFGF）、血管细胞黏附分子（vascular cell adhesion molecule, VCAM）水平低于治疗前，且联合组低于全身用药组（P＜0.05）；治疗前后两组均未检出单纯疱疹病毒（herpes simplex virus, HSV）、水痘-带状疱疹病毒（varicella-zoster virus, VZV）、爱泼斯坦-巴尔病毒(epstein-barr virus, EBV)、人疱疹病毒6型（human herpesvirus 6, HHV-6）。Spearman秩相关分析显示，房水中CMV核酸载量与IL-6、IL-8、IL-10、VEGF、BFGF、VCAM均呈正相关（P＜0.05）。结论：AIDS合并CMVR患者经全身联合局部抗病毒的疗效更佳，可更显著降低眼内液CMV核酸载量及相关炎症、生长因子水平，且房水CMV核酸载量与上述细胞因子水平呈正相关系。

Objective: To investigate the intraocular fluid characteristics of acquired immunodeficiency syndrome (AIDS) complicated with cytomegalovirus retinitis (CMVR) after antiviral treatment. Method: A retrospective analysis was conducted on the clinical data of 49 patients with AIDS and concomitant CMVR admitted to our hospital from November 2018 to December 2024. They were divided into a control group (n=23, 30 eyes) and a combination group (n=26, 30 eyes) according to different treatment methods. The control group received systemic antiviral treatment with intravenous sodium phosphonate, while the combination group received intravitreal injection of ganciclovir (GCV) on this basis. The intraocular fluid characteristics of the two groups were compared. Result: After treatment, the levels of CMV nucleic acid load, interleukin-6, IL-8, IL-10, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (BFGF), and vascular cell adhesion molecule (VCAM) in the intraocular fluid of both groups were lower than before treatment, and the combined group was lower than the control group (P<0.05); No HSV was detected in both groups before and after treatment EBV、VZV、HHV-6。 Spearman correlation analysis showed that the CMV nucleic acid load in aqueous humor was positively correlated with IL-6, IL-8, IL-10, VEGF, BFGF, and VCAM (P<0.05). Conclusion: AIDS patients with CMVR showed better efficacy after systemic and local antiviral treatment, and exhibited significant decreases in CMV nucleic acid load and related cytokines in aqueous humor.

目的：探讨临床分离的铜绿假单胞菌感染所致眼内炎的临床特点及对常用抗菌药物耐药情况，为临床合理使用抗菌药物提供治疗依据。方法：回顾2013年1月—2024年12月在中山大学中山眼科中心确诊感染铜绿假单胞菌的眼内炎患者资料，记录并分析患者临床特点及对常用抗菌药物耐药情况。结果：44例确诊感染铜绿假单胞菌的眼内炎患者，2例患者采取保守治疗，42例患者接受外科手术治疗。其中13例患者行玻璃体腔内注射抗菌药物及玻璃体切割术，10例患者行玻璃体切割术，19例患者行眼球摘除术。治疗后，1例患者视力达到20/400，3例患者视力为指数视力（finger count, FC），9例患者视力为手动视力（hand move, HM），5例患者视力为光感（light perception, LP），26例患者视力无光感（no light perception, NLP）。体外药敏试验显示，铜绿假单胞菌对阿米卡星、美罗培南、妥布霉素敏感度为100.0%；对庆大霉素敏感度为97.5%；对左氧氟沙星、环丙沙星敏感度为95.0%；对头孢吡肟、亚胺培南敏感度为80.0%；对头孢他啶、氧氟沙星敏感度为75.0%；对氯霉素、头孢唑啉、头孢呋辛、头孢曲松及复方磺胺甲噁唑的敏感度均为0%。结论：铜绿假单胞菌性眼内炎患者的视力预后较差，眼球摘除率居高不下。铜绿假单胞菌对阿米卡星、美罗培南、妥布霉素表现出较好的敏感性。

Objective: To explore the clinical characteristics and antibiotic resistance patterns of endophthalmitis induced by Pseudomonas aeruginosa at our hospital from January 2013 to December 2024, with the aim of providing evidence to support the rational clinical use of antimicrobial agents. Methods: A retrospective analysis was conducted on patients diagnosed with Pseudomonas aeruginosa endophthalmitis at Zhongshan Ophthalmic Center, Sun Yat-sen University, during the period from January 2013 to December 2024. Clinical features and antibiotic resistance profiles of the patients were documented and analyzed. Results: Among the 44 patients, 2 received conservative treatment. The remaining 42 patients underwent surgical intervention: 13 patients received intravitreal antibiotic injection combined with vitrectomy, 10 patients underwent vitrectomy alone, and 19 patients required enucleation. Post-treatment visual outcomes were as follows: 1 patient achieving 20/400 vision, 3 patients had with finger count (FC) vision, 9 with hand move (HM), 5 patients with light perception (LP), and 26 patients with no light perception (NLP). In vitro drug susceptibility tests revealed that Pseudomonas aeruginosa was 100.0% sensitive to amikacin, meropenem and tobramycin; 97.5% sensitive to gentamicin; 95.0% sensitive to levofloxacin and ciprofloxacin; 80.0% sensitive to cefepime and imipenem; 75.0% sensitive to ceftazidime and ofloxacin; and 0% sensitive to chloramphenicol, cefazolin, cefuroxime, ceftriaxone and cotrimoxazole. Conclusions: The visual prognosis of patients with Pseudomonas aeruginosa endophthalmitis remains poor, with a high rate of enucleation. The pathogen demonstrated favorable susceptibility to amikacin, meropenem, and tobramycin.

目的：分析染色体外环状DNA（extrachromosomal circular DNA, eccDNA）的分子特征及潜在功能，初步探索eccDNA在合并人类免疫缺陷病毒（human immunodeficiency virus, HIV）感染患者的白内障发病过程中的作用机制。方法：收集4例合并HIV感染的并发性白内障（complicated cataract, CC）患者及性别、年龄与之匹配的4例年龄相关性白内障（age-related cataract, ARC）患者晶状体囊膜，通过提取、滚环扩增及circle-seq对eccDNA进行全长测序，分析比较合并HIV感染的CC患者及ARC患者之间晶状体囊膜eccDNA的数量、长度分布、基因组元件分布及eccDNA相关差异基因功能富集情况。结果：合并HIV感染的CC患者晶状体囊膜中eccDNA数量较ARC患者增多，鸟嘌呤（guanine, G）和胞嘧啶（cytosine，C）碱基所占的比例（GC含量）较ARC患者减少。在CC患者及ARC患者中，eccDNA的长度在1 200 ~1 800 bp均分布最多，CC患者在2 000~2 200 bp之间呈现另一部分高峰，ARC组则在此区间eccDNA丰度极低。CC患者eccDNA来源基因组元件在CpG岛占比低于ARC组。 CC患者组eccDNA差异基因富集的通路多与钙信号通路、Apelin信号通路及cGMP-PKG信号通路相关。结论：合并HIV感染的CC患者与ARC患者晶状体囊膜eccDNA的分子特征存在差异，提示eccDNA可能通过基因表达调控晶状体前囊膜代谢功能影响CC的发生、发展。

Objective: To perform full-length sequencing of extrachromosomal circular DNA (eccDNA) in the lens capsule of patients with human immunodeficiency virus (HIV)-infected complicated cataract (CC) and age-related cataract (ARC). The aim is to analyze the molecular characteristics and potential functions of eccDNA and initially investigate the mechanism by which eccDNA contributes to the pathogenesis of cataract related to HIV infection. Methods: Lens capsules were collected from 4 CC patients who were co-infected with HIV and from ARC patients matched for gender and age. The eccDNA was sequenced following a process that included extraction, rolling circle amplification, and circle-seq. We then analyzed and compared the number, length distribution, genomic element distribution, and enrichment of differential gene functions associated with eccDNA in the lens capsules of CC patients co-infected with HIV and ARC patients. Results: The number of eccDNA molecules in the lens capsule of CC patients co-infected with HIV was significantly higher than that in ARC patients, while the GC content was lower.. In both CC and ARC patients, the majority of eccDNA lengths felll within the range of 1200 to 1800 bp. However, CC patients exhibited an additional peak between 2000 and 2200 bp, where the abundance of eccDNA in the ARC group was extremely low. Regarding genomic elements derived from eccDNA, the proportion in CC patients was lower than that in the ARC group within CpG islands. The pathways associated with differential gene enrichment of eccDNA in CC patients were primarily related to the calcium signaling pathway, Apelin signaling pathway, and cGMP-PKG signaling pathway. Conclusions: There are notable differences in the molecular characteristics of lens capsule eccDNA between CC patients with HIV infection and ARC patients.These finding suggest that eccDNA may influence the onset and progression of CC by regulating the metabolic functions of the anterior lens capsule through gene expression.

蜡样芽孢杆菌性眼内炎（Bacillus cereus endophthalmitis）是由蜡样芽孢杆菌经外源性/内源性途径感染引发的严重眼部疾病，以暴发性进展、预后不良为特征。典型临床表现为眼组织咖啡样溶解、前房咖啡色积脓及视网膜不可逆损伤，即使采用万古霉素抗感染联合玻璃体手术治疗，仍有75%～91%的患者难以恢复有效视力，约30%的患者因眼球内容物剜除或眼球摘除而致残。当前临床诊疗仍面临双重瓶颈：其一，蜡样芽孢杆菌致病机制复杂，核心因素尚未明确；其二，玻璃体切割术联合万古霉素治疗虽可延缓病程，但多数患者预后仍较差，诊疗策略有待优化。本文系统综述蜡样芽孢杆菌性眼内炎分子致病机制研究进展，基于溶细胞毒素[溶血素BL（hemolysin BL, HBL）/非溶血性肠毒素（non-hemolytic enterotoxin, NHE）/细胞毒素K（cytotoxin K, CytK）/溶血素(hemolysin）]的膜破坏作用和炎症反应、磷脂酶类的侵袭性与超氧化物歧化酶的免疫逃逸、菌体结构组分（鞭毛、菌毛、S层蛋白）致病效应以及宿主免疫应答[Toll样受体（Toll-like receptor, TLR）/NLRP3炎症小体（NLRP3 inflammasome）]失衡四个方面，整合分析国内外基础研究数据，以期为该病致病机制深度解析、靶向治疗策略探讨和转化医学前景展望等提供理论框架。

Bacillus cereus endophthalmitis is a severe ocular infection characterized by rapid progression and a poor prognosis, which can originate from either exogenous or endogenous sources. Clinically, it manifests as coffee-colored hemorrhages in ocular tissues, coffee-colored hypopyon in the anterior chamber, and irreversible retinal damage. Despite the implementation of infection control measures, such as vancomycin treatment and vitrectomy, 75%–91% of patients are unable to regain functional vision. Moreover, approximately 30% of patients require enucleation or removal of ocular contents, resulting in significant disability. The current clinical diagnosis and treatment of Bacillus cereus infections are confronted with two major challenges. Firstly, the pathogenic mechanisms are complex, and key contributing factors remain unidentified. Secondly, although vitrectomy combined with vancomycin can slow down the progression of the disease, the prognosis for most patients remains dismal, highlighting the urgent need for improved diagnostic and treatment strategies. This review conducts a systematic examination of the molecular pathogenic mechanisms of B. cereus endophthalmitis, integrating findings from both domestic and international studies. Specifically, this paper offers a comprehensive and systematic review of the latest research on the molecular pathogenic mechanisms of Bacillus cereus endophthalmitis, with a focus on four main areas: the membrane-damaging effects and inflammatory responses induced by cytolytic toxins (HBL/NHE/CytK/hemolysin); the invasiveness of phospholipases and immune evasion by superoxide dismutase; the pathogenic effects of bacterial structural components (flagella, pili, S-layer proteins);  the imbalance in host immune responses (TLR receptors/NLRP3 inflammasome). By integrating and analyzing research data from both domestic and international, this review aims to establish a theoretical framework. This framework is intended to enhance in-depth understanding of the disease’s pathogenic mechanisms, facilitate the exploration of targeted therapeutic strategies, and offer insights into the future prospects of translational medicine.

登革热是由登革病毒引起的全球性虫媒传染病，近年来发病率在全球范围内呈指数级增长。随着登革热的流行，其相关眼部并发症逐渐受到眼科医生的关注。登革相关眼病（dengue-associated ocular diseases, DAOD）作为登革热感染的重要系统性并发症其病理机制涉及多个方面，包括病毒亚型、非结构蛋白 1（non-structureprotein, NS1）病毒抗原、宿主的抗 DENV NS1 抗体及免疫炎症反应等，这些因素的相互作用，引发一系列眼部并发症。DAOD的临床谱系复杂，可累及结膜、葡萄膜、视网膜、视神经和眼外肌等多个眼部结构，病变严重程度个体间差异较大，从自限性结膜出血到威胁视力的视神经炎等，临床表现多样，进一步增加了诊断和治疗的难度。由于缺乏明确的诊断金标准，DAOD的诊断通常需结合患者的全身症状、登革热特异性抗体血清学检测，以及眼部症状、临床特征和影像学检查等进行综合分析。治疗上则需根据患者具体情况制定个性化方案，以缓解症状、防止病情恶化并促进康复。本文旨在全面综述 DAOD的流行病学特征、发病机制、临床表现、诊断及治疗策略等方面的研究进展，为临床医生提供更全面、更准确的指导，从而提高 DAOD的诊治水平，降低患者致残率。

Dengue fever is a globally prevalent insect-borne disease caused by dengue virus, and its incidence has witnessed an exponential rise worldwide in recent years. Alongside the dengue fever epidemic, its related ocular complications have gradually drawn the attention of ophthalmologists. As a significant systemic complication of dengue infection, Dengue-associated Ocular Diseases (DAOD) have a multifaced pathological mechanism. This encompasses various factors, such as viral subtypes, non-structural protein 1 (NS1) viral antigens, host anti-DENV NS1 antibodies, and immune inflammatory responses. The clinical spectrum of DAOD is intricate, affecting multiple ocular structures including the conjunctiva, uvea, retina, optic nerve and extraocular muscles. The severity of lesions varies greatly among individuals, ranging from self-limited conjunctival hemorrhage to vision-threatening conditions like optic neuritis. This wide array of clinical manifestations further complicates the diagnosis and treatment process. Given the absence of a definitive gold standard for diagnosis, the diagnosing DAOD typically necessitates a thorough analysis encompassing the patient's systemic symptoms, dengue-specific antibody serological testing, ocular symptoms, clinical features, and imaging examinations. Treatment approaches are tailored to each individual, aiming to alleviate symptoms, prevent exacerbations, and facilitate recovery. The objective of this article is to conduct a comprehensively review of the research advancements in the epidemiological characteristics, pathogenesis, clinical manifestations, diagnosis and treatment strategies of DAOD. It aims to furnish clinicians with more comprehensive and precise guidance, thereby enhancing the diagnosis and treatment of DAOD and reducing the disability rate among patients.

Fuchs葡萄膜炎综合征是一种主要累及眼前节的慢性前葡萄膜炎。由于病因不明，诊断主要依赖于临床表现，因此眼部结构改变对该病的诊治极为关键。长期慢性炎症致使Fuchs葡萄膜炎综合征患眼从角膜、前房至视网膜及脉络膜，均存在或明显或隐匿的结构改变。本文综述了患眼眼前节的特征性改变：角膜存在特征性的角膜后沉着物以及内皮细胞密度降低、形态改变；前房出现闪辉和细胞，房水中可检测到炎症因子和病毒；虹膜可见特征性萎缩，表现为脱色素和自体荧光改变。三者的结构改变直接反应炎症状态，可为病因机制研究提供线索。白内障和飞蚊症作为常见并发症，与反复的炎症相关，亦伴随着晶状体和玻璃体的结构改变。晶状体-玻璃体界面结构的改变为理解并发症的进展机制与防治方案提供了新思路。Fuchs葡萄膜炎综合征的眼底结构改变隐匿。黄斑区视网膜厚度是否改变尚未定论，另有多项研究认为视网膜血流密度降低。视盘神经节细胞层厚度降低可能与并发性青光眼相关。脉络膜也存在血管层厚度和血流密度改变，也许是慢性炎症的表现。总而言之，关于Fuchs葡萄膜炎综合征的眼部结构改变，尚有诸多疑问有待深入探索。

Fuchs uveitis syndrome is a chronic anterior uveitis that predominantly impacts the anterior segment of the eye. Since its etiology remains unclear, diagnosis largely relies on clinical manifestations.  Consequently, alternations in ocular structure play a pivotal role in both the diagnosis and treatment of this disease. Due to the persistent nature of chronic inflammation, a range of structural changes occur, spanning from the cornea and anterior chamber to retina and choroid. This article provides a detailed account of the characteristic changes in the anterior segment. In the cornea, characteristic keratic precipitates are observable, accompanied by a reduction in endothelial cell density and morphological alterations. The anterior chamber exhibits aqueous flashes and cells, where inflammatory factors and viruses can be detected. Additionally, characteristic iris atrophy is visible, presenting  as depigmentation and altered autofluorescence. These three factors collectively reflect the inflammatory state and progress with the course, potentially offering insights into the etiological mechanism. Concurrent cataract and floates, which are common complications associated with recurrent inflammation, accompanied by structural changes in the lens and vitreous. Structural alterations at the vitreol enticular interface, located between the posterior lens capsule and anterior vitreous, provide valuable clues regarding the pathogenesis of complications and provide new perspectives for therapeutic strategies. The structural changes in the fundus of Fuchs syndrome are often insidious. While it remains undetermined whether the retinal thickness in the macular region undergoes changes, numerous studies suggest a decrease in retinal blood flow density. Thinning of the ganglion cell layer in the optic disc may be linked to concurrent glaucoma. The choroid also experiences changes in the thickness of vascular layer and blood flow density, which could be a manifestation of chronic inflammation. In conclusion, numerous questions regarding the ocular structural changes in Fuchs uveitis syndrome still await further exploration.

目的：分析免疫抑制状态下，无猫接触史、不伴玻璃体混浊且视网膜呈现大片状黄白色坏死灶的弓形虫视网膜炎患者的误诊原因及临床表现。 方法：病例系列研究。收集2021年9月—2023年4月于中山大学中山眼科中心确诊的不典型弓形虫视网膜炎患者临床资料,分析其误诊原因、临床表现及治疗预后。结果：纳入3例患者（5眼），患者均为女性，其中1例对侧眼1年前诊断为“葡萄膜炎”导致无光感，其余2例均为双眼先后发病。年龄为31~34岁，从发病到确诊，病程1~2个月。3例患者均无猫接触史。均因全身疾病而使用大剂量免疫抑制药物：2例为慢性系统性红斑狼疮患者，不规则治疗后出现复发；1例患者因“暴发性肝坏死”，进行肝移植手术，术后使用免疫抑制抗排斥药物。眼底检查显示玻璃体无明显混浊，眼底图上有大片状黄白色视网膜病灶，在光学相干断层扫描（optical coherence tomography, OCT）上表现为坏死样改变。首诊均误诊为急性视网膜坏死或巨细胞病毒性视网膜炎，2例患者还伴有EB病毒阳性，行局部及全身抗病毒治疗，视力进一步下降伴坏死灶进一步扩大。转诊至中山大学中山眼科中心后，补充房水检测均提示弓形虫DNA强阳性。予抗弓形虫治疗后视网膜坏死灶明显吸收，视力提高。结论：在免疫抑制状态下，弓形虫视网膜炎可表现为非典型的大片状视网膜坏死、无玻璃体混浊及无猫接触史，易被误诊为其他视网膜炎症。临床医生应高度警惕免疫抑制人群中弓形虫视网膜炎的可能性，及时进行房水弓形虫DNA检测有助于明确诊断并改善预后。

Objective: Vitreous opacity and cat contact history are two major diagnostic criteria for toxoplasmic retinochoroiditis. This study aimed to explore the causes of misdiagnosis and the clinical manifestations of patients with toxoplasmic retinochoroiditis who present with large yellowish-white necrotic retinal lesions but lack both a history of cat exposure history and vitreous opacity. Methods: This was a case series study. We collected clinical data from three patients diagnosed at Zhongshan Ophthalmic Center, Sun Yat-sen University between September 2021 and April 2023. All patients presented without a history of cat contact or vitreous opacity.The causes of misdiagnosis, clinical features, and treatment outcomes were analyzed. Results: The study included three patients (five eyes), all of them were female. One patient had no light perception in the contralateral eye after a 3-year disease course, while the other two exhibited bilateral involvement. The patients’ ages ranged from 31 to 34 years, and the duration of symptoms before diagnosis was 1–2 months. None reported exposure to cats, but all were immunocompromised: two had systemic lupus erythematosus (SLE) with irregular treatment and relapse, and one had underwent liver transplantation for "fulminant hepatic necrosis" and was receiving post-transplant immunosuppression. Fundus examination revealed no vitreous opacity, and retinal lesions appeared as large yellowish-white changes on fundus photography and necrotic changes on optical coherence tomography(OCT). Initially, all cases were misdiagnosed as acute retinal necrosis or cytomegalovirus retinitis, with 2 cases testing positive for herpesvirus DNA. Antiviral therapies were applied, which led to worsened vision and progression of the lesions. Subsequent referral testing of aqueous humor confirmed the presence of Toxoplasma gondii DNA. Anti-toxoplasma treatment resulted in significant resolution of the lesions and improvement in vision. Conclusions: In immunocompromised individuals, the presence of large necrotic retinal lesions without vitreous opacity or a history of cat exposure should raise suspicion for toxoplasmic retinochoroiditis. This awareness is crucial to prevent delayed diagnosis and subsequent vision loss.

本文基于实验室实践经验，探讨病原宏基因组测序（metagenomic next-generation sequencing, mNGS）技术在眼部感染性疾病中的应用策略与挑战。尽管mNGS凭借无偏倚检测优势成为疑难感染诊断的重要工具，但受限于流程复杂、干扰因素多及解读门槛高，目前尚不宜作为一线常规检测手段。针对眼部标本微量、类型多样及背景复杂的特殊瓶颈，本文提出了湿实验环节保留人源核酸、构建本地化背景微生物库、以及利用宿主数据同步筛查肿瘤风险等关键解决方案。文章强调，通过强化临床与实验室的多学科协作（multidisciplinary teams, MDT），可有效提升结果解读的准确性，从而推动该技术在眼科诊疗中的规范化与精准化应用。

Based on laboratory experience, this article reviews the applications and challenges of metagenomic next-generation sequencing (mNGS) in ocular infectious diseases. While mNGS serves as a valuable tool for diagnosing difficult infections due to its unbiased detection capabilities, it is not yet suitable as a first-line routine test given its complex workflow and interpretation requirements. Ocular specimens, characterized by trace nucleic acid amounts, high diversity, and complex backgrounds, present unique technical bottlenecks. To address these, this article proposes key strategies, including retaining human nucleic acids during wet-lab processing, constructing a localized background microbial library, and utilizing host data for concurrent tumor screening. The study emphasizes that strengthening multidisciplinary teams (MDT) between clinical and laboratory departments is essential to promote the standardization and precision of mNGS applications in ophthalmology.