Comorbidity of Keratoconus and Fuchs’ Corneal Endothelial Dystrophy: A Review of the Literature

Introduction: Comorbidity of keratoconus (KC) and Fuchs’ corneal endothelial dystrophy (FD) has been sporadically reported in the literature since the early nineties. This review summarizes findings from the related literature while examining the possibilities related to the concurrent development of these disorders and the clinical significance for the clinician. Methods: NLM/PubMed, Ovid, Google Scholar, Cornea, and Cochrane database were reviewed for research papers presenting cases of comorbid KC and FD published between January 1990 and July 2019. Results: Fifteen papers which presented 69 cases were included in the study. Most cases were women (56.5%), involvement was bilateral (59.4%), and the age range was wide (15–82 years) with a normal distribution. Incidence is expected to be approximately 1 per 100,000. FD is the most frequent comorbid corneal dystrophy diagnosed in KC patients. There are 4 distinct possibilities for the cooccurrence of KC and FD, the most likely being that of chance. Conclusion: The overall incidence of these disorders found in combination is very low and, in absence of other conclusively proven hypotheses, most likely attributable to chance. The treatment plan should be tailored to the needs of the individual patient, since the diagnosis can be made in any stage of life and could be part of a more complex presentation that includes another pathology of the cornea or senile cataract. The inclusion of preoperative topography and specular microscopy as routine in cataract preoperative assessment would protect against any postoperative complications in these patients.