Mucus Fishing Syndrome: Case Series and a Narrative Review of Literature

Mucus fishing syndrome (MFS) is a self-induced mechanical ocular surface disorder characterized by compulsive removal of mucus strands from the conjunctival fornices. MFS is frequently underrecognized and misdiagnosed because of its poorly characterized pathophysiology and discreet behavioral trigger. We present a case series of MFS and review the current literature addressing its epidemiology, pathophysiology, psychiatric associations, and management.

We report two clinical cases and provide a comprehensive literature search across PubMed, MEDLINE (Ovid), and Google Scholar describing the ocular surface biology and behavioral and neuropsychiatric mechanisms of MFS.

Two females, aged 37 and 24 years, presented with excessive mucus production and underlying psychiatric conditions. Across six studies, 59 cases were identified, with a mean age of 50.6 ± 18.4 years (range, 16-86 years). The majority were female (81.4%), and nearly all (96.6%) had a concurrent ocular surface disorder, most commonly dry eye disease, meibomian gland dysfunction, or blepharitis. Psychiatric or behavioral comorbidities were reported in 21.1% of patients, including anxiety, depression, insomnia, obsessive-compulsive disorder, and substance use disorders.

Ocular surface inflammation and maladaptive behavioral reinforcement contribute to the development of MFS. Following diagnosis, patient education and behavioral counseling are essential to disrupting the fishing cycle.