Posterior Polymorphous Corneal Dystrophy: A Case Report

Abstract

Background: Posterior polymorphous corneal dystrophy (PPCD) is a rare hereditary disorder of the corneal endothelium and Descemet’s membrane. Its heterogeneous clinical presentation accounts for the term "polymorphous" and may lead to diagnostic confusion, particularly in the presence of anterior segment abnormalities, with potential implications for patient management. Case Presentation: We describe a female patient presenting with a corneal epithelial lesion initially suggestive of a primary epithelial pathology. Careful examination of the fellow eye revealed subtle endothelial alterations. Anterior segment optical coherence tomography (AS-OCT) demonstrated irregularities of Descemet’s membrane, while specular microscopy (SM) showed endothelial cell polymorphism and polymegathism, consistent with PPCD. No family history of corneal dystrophy was identified. Conservative ocular surface treatment was initiated, resulting in clinical improvement and epithelial healing. Long-term follow-up was recommended, and endothelial keratoplasty was discussed as a potential therapeutic option. Discussion: This case emphasizes the importance of systematic endothelial evaluation in patients presenting with unexplained epithelial corneal lesions. The polymorphous nature of PPCD may mimic other endothelial or inflammatory corneal disorders, such as herpetic keratitis or early Fuchs endothelial dystrophy, potentially leading to misdiagnosis. Multimodal imaging, including AS-OCT and SM, is essential for accurate diagnosis and assessment of endothelial involvement. Conclusion: PPCD may present with anterior corneal epithelial changes, highlighting the need for careful endothelial assessment in atypical presentations. Early recognition is critical to ensure appropriate monitoring and to prevent progression to endothelial decompensation.