Anterior uveitis of unknown etiology characterized by diffuse stellate keratic precipitates (KP) with iris heterochromia.
- Triad:
- Heterochromia
- Predisposition to cataract & glaucoma
- Keratitic precipitates on the posterior corneal surface
History:
Ernst Fuchs was the first in 1906 to report both the clinical and pathologic features of a consistent number of patients with a chronic low grade anterior chamber inflammation, heterochromia, and cataract. This association was named after as Fuchs’ Heterochromic Iridocyclitis (FHI). Nowadays FHI is one of the most common forms of anterior uveitis, accounting for up to 8% of endogenous uveitis seen in referral center.
Aetiology
Aetiology is unknown.
Associated conditions:
Secondary to which FHIC may develop
- Toxoplasmosis, toxocariasis
- Sarcoidosis
- Rubella vaccination
- Cytomegalovirus (CMV), herpes simplex virus, chikungunya virus infections
- Retinitis pigmentosa
- Horner’s syndrome
- Usher’s syndrome
- Previous trauma
Clinical features
Slow progression over time, without substantial reduction of visual acuity until the development of significant vitreous opacities or cataract.
- Blurred vision (M/C)
- Mild discomfort
Complications
- Cataract
- Secondary glaucoma (M/serious)
- Refractory to medical management
- Vitreous opacities
Diagnosis
Usually diagnosed 2 years after symptoms onset on average.
- Keratic precipitates (M/C)
- Iris heterochromia
- Iris atrophy (moth-eaten appearance)
Amsler–Verrey sign:
Presence of blood (hyphema) in the aspirated vitreous fluid, in paracentesis of the anterior chamber
Due to iris atrophy usually seen in FHI and exposure of the fragile iris vasculature to the vitreous fluid
Management
- Short course of topical corticosteroids (DOC)