[Clinical features and treatment prognoses of Pythium keratitis]

Objective: To analyze the clinical features and evaluate the prognoses of Pythium keratitis. Methods: It was a retrospective study. The clinical characteristics, confocal microscopic image characteristics, treatment and curative effect of 6 cases of Pythium keratitis identified by DNA sequencing from June 2017 to June 2019 were reviewed retrospectively. Results: Among the 6 patients, there were 4 males and 2 females. All cases were monocular. The age was (58.7±11.3) years (range, 52 to 72 years). Keratopathy under a slit lamp was characterized by a dry ulcer surface, burr signs, satellite foci and pseudopodia around the ulcer. An elevated lesion was observed in 2 patients, and no obvious immune ring structure was observed in all patients. Confocal microscopy did not reveal any specific characteristics of Pythium infection. All patients did not respond well to antifungal drugs and received keratoplasty. Three patients had postoperative recurrence. The recurrence time was 4-6 days after the first operation and 2-3 days after the second operation. Two patients underwent two and three corneal transplants, respectively, after recurrence, but evisceration was required finally. Conclusions: Pythium keratitis is rare and can hardly be distinguished from common fungal infections in clinical manifestations and auxiliary examinations. The disease progresses rapidly, the rates of recurrence and evisceration after keratoplasty are both high, and DNA sequencing is the key to identifying the etiology, which should be paid more attention. (Chin J Ophthalmol, 2021, 57: 589-594).