病例18　44岁女性，右眼植物外伤后眼红痛1个月

CASE 18　A 44-year-old female injuried from plant, red eye and sever pain in the right eye for 1 month

见图1-29。See Fig. 1-29.

鉴别诊断

Differential Diagnosis

◎ 棘阿米巴性角膜炎：早期症状不典型，表现为角膜上皮假树枝状溃疡，上皮及上皮下浸润，放射状游走性神经炎。进展期表现为基质溃疡、环形浸润、卫星灶、前房积脓。晚期表现为角膜基质化脓或坏死、变薄和穿孔。

◎ Acanthamoeba keratitis: Early signs may be mild and nonspecif ic, including epithelial pseudodendrites, epithelial or subepithelial inf iltrates, and radial keratoneuritis. Later signs include stromal ulcer, ring-shaped inf iltrates, satellite lesions,hypopyon. Advanced signs include stromal suppuration,necrosis, thinning and corneal perforation.

◎ 真菌性角膜炎：角膜溃疡多呈灰白色羽毛状或干燥的豆腐渣样，可有伪足，前房可伴积脓，结膜充血明显。

◎ Fungal keratitis: The corneal lesion has a white/gray inf iltrate with feathery borders. There might be satellite lesions with hypopyon and conjunctival congestion as well as purulent secretions.

◎ 病毒性角膜炎上皮型：病毒性角膜炎上皮型可表现为上皮树枝状溃疡、地图状溃疡以及边缘性溃疡。典型的树枝状溃疡可见树枝末端膨大。而棘阿米巴性角膜炎的假树枝状上皮病变表现不同。

◎ Viral epithelial keratitis: Viral epithelial keratitis usually presents dendritic ulcer, geographic ulcer, and marginal keratitis. Dendritic epithelial keratitis has round spotlike widenings at the endings of the epithelial erosions.Pseudodendritiformic epitheliopathy in acanthamoeba keratitis is differential.

◎ 细菌性角膜炎：主要表现为角膜溃疡或者角膜脓性浸润，进展迅速，多伴前房积脓。棘阿米巴性角膜炎多表现为亚急性或者慢性。

◎ Bacterial keratitis: The corneal ulcer or corneal purulent inf iltration is rapidly formed and progressed, usually accompanied by severe hypopyon in the anterior chamber.Acanthamoeba keratitis generally presents the features of subacute or chronic onset and gradual progression.

◎ 表麻药相关性角膜病变：表现为持续性角膜上皮缺损、角膜溃疡以及角膜环形浸润。患者通常有表麻药滥用史。

◎ Anaesthetic abuse keratopathy: Anaesthetic abuse keratopathy has been characterised by persistent epithelial defects, keratitis ulcer and ring inf iltration of the cornea.The patient had the history of using topical anaesthetics.

病史询问

Asking History

◎ 疾病发生之前是否有长期角膜接触镜配戴史，是否用自来水清洗接触镜镜片以及配戴角膜接触镜游泳，有角膜异物及角膜擦伤史。

◎ The history of contact lenses wearing and their cleaning solutions, clean contact lens with tap water, wear contact lens in swimming pool, foreign bodies or minor bruises in cornea.

◎ 是否伴剧烈疼痛。

◎ Accompany with massive pain.

眼部检查

Examination

◎ 视力下降。

◎ Visual acuity is decreased.

◎ 裂隙灯检查：早期以角膜上皮假树枝状溃疡及放射状神经炎为主要表现；进展期为角膜基质溃疡、环形浸润、卫星灶、前房积脓；晚期出现角膜基质化脓或坏死、变薄和穿孔。

◎ Slit lamp examination: Early signs include epithelial pseudodendrites and radial keratoneuritis. Later signs include stromal ulcer, ring-shaped inf iltrates, satellite lesions,hypopyon. Advanced signs include stromal suppuration,necrosis, thinning and corneal perforation.

实验室检查

Lab

◎ 角膜刮片在表面麻醉后于裂隙灯下进行。滋养体和包囊可以用革兰氏和吉姆萨染色。

◎ Involved area of cornea can be scraped with a sterile instr ume nt under topical anesthesia at the slit lamp. Acanthamoeba trophozoites and cysts can also be identif ied with the help of Gram and Giemsa.

◎ 阿米巴培养可以用含大肠杆菌的非营养琼脂。

◎ The culture specimen can then be inoculated into a dish of E. coli plated over non-nutrient agar.

◎ 共聚焦显微镜检查：包囊表现为圆形，双壁，高密度影像，直径15~20μm（图1-30）；滋养体表现为不规则高密度影像，其中心或偏中心可见致密的核，直径25~40μm（图 1-31）。

◎ Laser Confocal microscope: The acanthamoeba cyst presentes a round high-contrast particle, 15 to 20 μm in diameter, with a double wall (Fig. 1-30). The trophozoite presentes an irregular high-contrast particle, without an apparent wall, 25 to 40 μm in diameter and with a round conspicuous nucleus (Fig. 1-31).

诊断

Diagnosis

棘阿米巴性角膜炎。

Acanthamoeba keratitis.

治疗

Management

◎ 彻底清创。

◎ Extensive epithelial lesion debridement.

◎ 局部抗阿米巴药：常用0.02%聚六亚甲基双胍(poly he x amethylene biguanide, PHMB)和 0.02%氯己定二葡萄糖酸盐。

◎ Topical polyhexamethylene biguanide (PHMB) 0.02%and chlorhexidine diglucoate 0.02% are commonly used biguanides.

◎ 控制疼痛：口服非甾体抗炎药。

◎ Systematic non-steroid anti-inf lammatory drug.

◎ 对药物治疗欠佳的患者，可行板层 / 穿透性角膜移植术。

◎ In therapy resistant cases, lamellar/penetrating keratoplasty may be applied.

患者教育和预后

Patient Education & Prognosis

◎ 避免自来水清洗镜片以及配戴角膜接触镜游泳。棘阿米巴性角膜炎由于早期易误诊及治疗困难，预后差。目前抗棘阿米巴的药物品种少且特异性不强，如果角膜穿孔须行穿透性角膜移植手术，但复发率较高。

◎ Do not clean contact lens with tap water or wear contact lens in swimming pool. There is often a poor prognosis because of a signif icant delay in diagnosis and frequently a lack of effective medical management. If corneal perforates,penetrating keratoplasty is only effective surgical option,but the risk of recurrence is high.