Contrastive Latent Functional Model.

Delusional infestation (DI), historically known as Ekbom syndrome, is a rare phenomenological syndrome characterized by the fixed, false belief that one is infested by living organisms, such as parasites, worms, mites, bacteria, or fungi. While the term “Ekbom syndrome” is still used, “delusional infestation” is increasingly preferred in the literature to reflect the diverse range of pathogens reported by patients. The condition is categorized into two subtypes: primary DI, in which the delusion presents as the sole psychiatric manifestation, and secondary DI, in which the delusion occurs as a symptom of an underlying condition []. The latter may arise from other psychiatric disorders, organic medical conditions such as cerebrovascular disease or Parkinson’s disease, or as a direct result of substance use and abuse. DI carries a significant disease burden, often leading to social isolation and self-destructive behaviors, such as skin excoriation or the application of caustic substances. While some patients may maintain a degree of outward functionality, the condition frequently results in high healthcare utilization and significant distress. Although delusions often resist medical evidence, leading patients to seek help from dermatologists rather than psychiatrists, treatment can significantly reduce distress and improve quality of life, even when the underlying conviction remains [].