Table 1.
Comparison of the clinical features between the common viral anterior uveitis aetiologies
| Variables | Herpes simplex virus (HSV) | Varicella-zoster virus (VZV) | Cytomegalovirus (CMV) | Rubella virus (RV) Rubella associated FUS | ||
|---|---|---|---|---|---|---|
| Acute (Posner Schlossman like syndrome) | Chronic | |||||
| Chronic CMV anterior uveitis | CMV-associated Fuchs uveitis syndrome (FUS) | |||||
| Age | 40-50 years | >60 years Immuncompromised patients (any age) | 30-50 years | 40-70 years | 40-70 years | 20-40 years (Mean: 35±12 years) |
| Gender | No predilection | No predilection | Males (65%) | Males | Males (80%) | No predilection |
| Race | All | All | Predominantly Asian population | Western population | Predominantly Asian population | Western population |
| Laterality | Mostly unilateral (bilateral in 18%) | Unilateral | Unilateral | Mostlty unilateral (bilateral in 7%) | Mostly unilateral (bilateral in 7%) | Mostly unilateral (bilateral in 14%) |
| Course | Acute, recurrent | Acute, recurrent | Acute, recurrent | Chronic | Chronic | Chronic |
| Intraocular pressure | Acute spikes (38-90%) | Acute spikes (40-75%) | Very high (up to 50 mmHg) during acute episodes (100%) | Very high (43.5±9.8 mmHg); persistently elevated | Very high (43.5±9.8 mmHg); persistently elevated (73.3%) | Persistent elevation (25%) |
| Dermal manifestations | h/o fever or blisters/grouped vesicles occurring at the border of the eyelids with diffuse edema | Vesicular rash involving the ophthalmic division of the trigeminal nerve | None | None | None | None |
| Conjunctival injection | Moderate to severe | Moderate to severe | Mild | Mild | Mild | None |
| Corneal sensation | May be reduced | May be reduced (more profound and diffuse hypoaesthesia than HSV) | Intact | Intact | Intact | Intact |
| Epithelial keratitis | Dendritic ulcers (usually branching, with well-developed terminal bulb) | Pseudodendritic ulcers (less regular branching, few terminal dilatations) | None | None | None | None |
| Stromal keratitis | Disciform keratitis; Interstitial keratitis; Immune ring keratitis | Nummular keratitis; Limbal keratitis; Immune ring keratitis | Immune ring keratitis | None | ||
| Corneal scars | Present (33%) | Present (25%) | Rare | None | ||
| Endotheliitis | May be present | May be present | May be present | May be present | Nodular endothelial lesions surrounded by a translucent halo and occasional pigmentation | None |
| Keratic precipitates | ||||||
| Size | Small to medium | Small to medium | Medium to large (39%) | Small | Fine and stellate (44%) | Fine, may be stellate |
| Distribution | Central, paracentral, diffuse, may be in Arlt’s triangle or in the same distribution as inflamed cornea | Central, paracentral, diffuse, may be in Arlt’s triangle or in the same distribution as inflamed cornea | Single or few, distributed centrally or in peripheral cornea; may have coin like lesions | May have a coin like lesions | Diffusely distributed; may have a coin like lesions (ring or linear pattern) | Diffuse |
| Colour | White, may be pigmented | White, may be pigmented | White or gray | White or gray, may be brown | White or gray, may have pigmentation | White, never pigmented |
| Endothelial cell count | Normal | Normal | Reduced | Reduced | Reduced | Normal |
| Anterior chamber inflammation | Moderate to severe | Severe. Usually more than HSV | Mild | Mild | Mild | Mild |
| Iris | ||||||
| Iridoplegia | May be present during acute phase causing pupil flattening or D shaped pupil | May be present during acute phase causing pupil flattening or D shaped pupil | Absent | Absent | Absent | Absent |
| Iris atrophy | Sectoral or patchy atrophy with transillumination defects, spiral iris atrophy | Sectoral atrophy with transillumination defects, rarely massive iris atrophy with gross sphincter damage | Mostly absent, rarely diffuse stromal iris atrophy | Rarely sectoral, stromal iris atrophy, no transillumination defects | Diffuse stromal iris atrophy, no transillumination defects | Diffuse atrophy, fine iris transillumination defects |
| Posterior synechiae | May be present | May be present | Absent | Absent | Absent | Absent |
| Pupil shape | May be irregular | May be irregular | Round | Round | Round | Round |
| Elevated IOP | Elevated (38-90%) | Elevated (40-75%) | Elevated (100%) | Elevated (69%) | Elevated (25%) | |
| Cataract | Present in 28-35%, later in onset | Present in 27-30%, later in onset | 23%, later in onset | 75%, later in onset | At the time of presentation (47%) | |
| Glaucoma | Present in 18-54% | Present in 30-40% | 23% | 36% | ||
| Vitritis | 43% | 83% | 0% | 9% | Very rare | Always present |