Mooren's ulcer: a multifactorial autoimmune peripheral ulcerative keratitis and current treatment protocols

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, the work 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. This work recommend a tiered, individualized approach to treatment and advocate for future multicenter studies to validate diagnostic protocols and establish evidence-based clinical guidelines.