Mooren's Ulcer: A Multifactorial Autoimmune Peripheral Ulcerative Keratitis and Current Treatment Protocols

Yiming Wu^1,2Yujie Zhang¹Yuchong Feng¹Xueer Zheng²Yuan Lin¹Liying Zhang²Su Zhao²Yu Su¹Han Cai¹Longqin Lin¹Hao Gu²Huping Wu^1*Shangkun Ou^1,2*

• ¹Xiamen University, Xiamen, China
• ²Department of Ophthalmology, Affiliated Hospital of Guizhou Medical University, Guiyang, China

Mooren's Ulcer (MU) is a rare, chronic, and painful form of autoimmune peripheral ulcerative keratitis (PUK), with an elusive etiology and a risk of corneal perforation and vision loss. Despite numerous proposed triggers, including parasitic infections, hepatitis C virus, ocular trauma, and surgery, the pathogenesis of MU remains unclear, and diagnosis continues to rely heavily on exclusion. A key controversy in current clinical practice lies in the absence of standardized diagnostic criteria and consensus treatment protocols. This review addresses this gap by presenting a comprehensive and structured diagnostic framework for MU, particularly emphasizing laboratory and immunological testing strategies to facilitate accurate differential diagnosis. To our knowledge, this is the first review to systematize these diagnostic components in detail. In addition to summarizing the latest findings on epidemiology, etiology, pathology, and classification, we also review the evolving role of advanced imaging, histopathology, and tear-based markers in MU diagnosis and monitoring. Treatment options, ranging from immunosuppressive therapy to surgical intervention, are discussed based on disease severity. We recommend a tiered, individualized approach to treatment and advocate for future multicenter studies to validate diagnostic protocols and establish evidence-based clinical guidelines.