Delusions of ocular parasitosis

Purpose: To describe four cases of delusions of parasitosis in which self-inflicted ocular trauma occurred. Delusions of parasitosis is a somatic delusional disorder in which patients have the irrational belief that their bodies are infested by parasites or other infectious organisms. Self-inflicted trauma can result from attempts to eliminate the supposed infestation. Methods: We reviewed the case histories of four patients (one male, three females, 35 to 45 years of age) who presented with complaints of ocular infestation but had no evidence of infectious ocular disease. The characteristics of these cases were compared with the features of delusions of parasitosis. Results: All patients maintained their beliefs regarding infestation, despite extensive clinical and laboratory investigations that found no evidence of infectious diseases. Self-inflicted eye injury, associated with attempts to eliminate the infestation, occurred in each case. Conclusions: The cases presented in this report are consistent with a diagnosis of delusions of parasitosis. The eye can be a principal focus of attention in this disorder, which may lead to vision loss caused by self-inflicted injury.