Primary corneal guttata: Distinctive observations and emerging insights – A scoping review

Abstract

Primary cornea guttata (PCG) is a corneal endothelial condition characterized by small, focal excrescences on Descemet’s membrane. Although it may mimic early Fuchs endothelial corneal dystrophy (FECD), PCG is usually asymptomatic, with no associated corneal edema or visual impairment. The clinical significance of PCG remains incompletely understood. This scoping review aimed to synthesize available evidence regarding the epidemiology, clinical presentation, endothelial morphometry, and risk factors associated with PCG. A systematic search was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews guidelines across multiple databases, including PubMed, ScienceDirect, ClinicalKey, EBSCOhost, Ovid, Web of Science, and Google Scholar, yielding 540 records. After removing duplicates and screening titles and abstracts, seven full-text articles were assessed, with five studies ultimately included in the final synthesis. Across these studies, PCG was most commonly observed in middle-aged to elderly individuals, with a higher prevalence in women. Most cases were detected incidentally during routine ophthalmologic examinations, without evidence of corneal edema or progression to FECD. Morphometric analyses reported decreased endothelial cell density and increased polymegethism and pleomorphism in specific populations, although findings varied. Prevalence differed across ethnic groups, with higher rates reported in Hispanic populations and variable findings among Asian cohorts. Identified risk factors included age, female sex, lower body weight, lower body mass index, and smoking history. Overall, PCG exhibits consistent demographic and clinical patterns but remains under-researched, with limited longitudinal data and an unclear natural history. These findings highlight the need for further studies to better understand the pathophysiology, progression, and clinical implications of PCG.