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.