Association of Fuchs Heterochromic Iridocyclitis with Multiple Sclerosis.

Purpose: To draw attention to the higher proportion of Fuchs heterochromic iridocyclitis (FHI) cases in patients with multiple sclerosis (MS).

Materials and methods: Retrospective study of data collected at the Center for the Diagnosis and Treatment of Uveitis.

Results: An analysis of the medical records of 3016 patients with uveitis (in the years 2003-2020) was performed with a focus on MS. MS-associated uveitis was diagnosed in 90 patients (3%): anterior uveitis (n = 7), intermediate uveitis (n = 23), retinal vasculitis (n = 24), and panuveitis (n = 36). A clinical examination revealed signs of FHI in the anterior segment in 11 out of 90 cases (12%). Atypical manifestations of FHI included a higher incidence of bilateral involvement (45%), retinal vasculitis (27%), and vitreous snowballs (18%). The diagnosis of FHI preceded the diagnosis of MS in 4 cases. The median latency was 10.5 (range 8-15) years. In 4 patients, the diagnosis of demyelinating disease was established within one year of the diagnosis of FHI. We recommended a neurological examination for optic neuritis (n = 1), paresthesia (n = 3), relapse of motor deficit (n = 1), and screening of etiology in cases with involvement of the posterior segment (n = 3). In the other 3 cases, the diagnosis of MS preceded the diagnosis of FHI, with a median latency of 13 (range 8-19) years.

Conclusion: We detected clinical symptoms of FHI in 12% of uveitis cases associated with MS, more often in bilateral manifestations of intraocular inflammation. Based on our experience, we recommend an investigation of the medical history of patients with FHI for manifestations of sensitive, sensory and motor deficits, especially in bilateral cases.