Differentials
Ocular lymphoma
SIGNS / SYMPTOMS
Ocular lymphoma and uveitis presentation are often similar and overlap. Differentiation is difficult without testing.
Ocular lymphoma is considered to be a neoplastic masquerade syndrome.
INVESTIGATIONS
Flow cytometry and cell phenotype show tumour cells and vitrectomy aids in removal of cells for analysis.
Leukaemia
SIGNS / SYMPTOMS
Leukaemia is considered to be a neoplastic masquerade syndrome.
Inflammatory cell infiltration of the eye is a relatively rare manifestation of leukaemia. This can cause a layering of white blood cells in the anterior chamber, forming a 'pseudohypopyon' that can occur during blast crisis or during relapse.
Leukaemic pseudohypopyon should be considered based on non-response to topical corticosteroids, as well as the absence of a fibrin reaction in the anterior chamber.
INVESTIGATIONS
Anterior chamber tap can be performed for cytology to confirm.
Intra-ocular solid tumours
SIGNS / SYMPTOMS
Intra-ocular solid tumours, both primary and metastatic, are considered to be neoplastic masquerade syndromes.
Ocular metastatic tumours may infiltrate the uveal tract, mimicking granulomatous inflammatory diseases or scleritis.
INVESTIGATIONS
Cases of suspected metastatic disease may require a comprehensive radiographical metastatic evaluation using CT/PET imaging.
Intra-ocular foreign body
SIGNS / SYMPTOMS
A complete history may identify a recent traumatic injury or high-risk activities (e.g., metal hammering). Therefore, a painful, red eye is more likely to be due to a foreign body than to uveitis.
An intra-ocular foreign body is considered to be a non-neoplastic masquerade syndrome.
INVESTIGATIONS
Initial test is ultrasound of the globe to visualise the foreign body. A CT scan may identify a metallic foreign body. An electroretinogram may help to identify the level of iron and copper toxicity.
Ocular ischaemia syndrome
SIGNS / SYMPTOMS
Patients have a history of poorly controlled diabetes, severe cardiovascular disease, and/or symptoms of transient ischaemic attack or stroke.
Ocular ischaemia syndrome is considered to be a non-neoplastic masquerade syndrome.
INVESTIGATIONS
Delay in filling of the blood vessels of the retina and choroid on fluorescein angiogram.
Echocardiogram, carotid Doppler, magnetic resonance angiography, and magnetic resonance venography aid in the diagnosis of the cardiovascular or cerebrovascular aetiology.
Retinal detachment
SIGNS / SYMPTOMS
In cases of chronic rhegmatogenous retinal detachment, intra-ocular inflammation, hypotony, or choroidal detachment may occur.
Retinal detachment is considered to be a non-neoplastic masquerade syndrome.
Anterior segment inflammation related to retinal detachment is also known as Schwartz syndrome.
INVESTIGATIONS
A careful peripheral retinal exam is required to rule out this condition. Scleral depression or B-scan ultrasonography may be required.
Glaucoma (acute angle closure)
SIGNS / SYMPTOMS
There may be a red eye, reduced visual acuity, and aching eye or brow pain. The patient may see ‘halos’ around lights. There may be headache, nausea, and vomiting.
The patient is typically older than 40 years and is long sighted.[21] Women are more likely to have angle-closure glaucoma than men.[21] Eskimo, Chinese, and Indian people are also more at risk of angle-closure glaucoma.[21]
Anticholinergic topical pupil dilators (e.g., cyclopentolate or atropine) or systemic medication (e.g., sulfonamides, topiramate, phenothiazines) can induce angle narrowing.
INVESTIGATIONS
Gonioscopy is the definitive test for diagnosing angle closure. The trabecular meshwork is not visible in angle closure because the peripheral iris is in contact with it.
Slit-lamp examination shows a shallow anterior chamber and signs of glaucoma: large optic cup, narrowing of the neuroretinal rim, splinter haemorrhage, nerve fibre loss.
In acute attacks, intra-ocular pressure rises rapidly to relatively high levels, typically above 40 mmHg.
Scleritis
SIGNS / SYMPTOMS
There is severe ocular pain and redness (prominent feature), but no discharge. Reduced visual acuity may be present. Often associated with systemic diseases, such as rheumatoid arthritis, granulomatosis with polyangiitis, systemic lupus erythematosus, and relapsing polychondritis.
On exam, there is deep scleral vessel engorgement and pain on ocular palpation. Visual acuity and pupillary reactions may be abnormal depending on the position of the scleritis on the globe (anterior or posterior).
INVESTIGATIONS
Erythrocyte sedimentation rate and C-reactive protein may be elevated in inflammatory conditions.
Rheumatoid factor may be positive in some patients with rheumatoid arthritis or systemic lupus erythematosus.
c-antineutrophil cytoplasmic antibody may be positive in granulomatosis with polyangiitis.
Absence of fluorescein staining.
Episcleritis
SIGNS / SYMPTOMS
There is acute onset of redness and pain. Often the patient describes the redness in a specific area of the eye and may have noticed a small nodule adjacent to this area. There is no discharge. The patient may have associated underlying rheumatoid arthritis, granulomatosis with polyangiitis, or systemic lupus erythematosus.
On exam, there is sectoral redness in one or both eyes. A nodule can be present over the area. Visual acuity and pupillary reactions are normal.
INVESTIGATIONS
Erythrocyte sedimentation rate and C-reactive protein may be elevated in inflammatory conditions.
Rheumatoid factor may be positive in some patients with rheumatoid arthritis or systemic lupus erythematosus.
c-antineutrophil cytoplasmic antibody may be positive in granulomatosis with polyangiitis.
Absence of fluorescein staining.
Allergic conjunctivitis
SIGNS / SYMPTOMS
Typically presents with a red eye and discharge but without significant pain, photophobia, or changes in vision. There is no history of trauma.
With allergic conjunctivitis, there may be a history of allergen exposure (could include topical eye medication), possible seasonal recurrence, or associated atopic symptoms (vernal conjunctivitis). There is a rapid onset after allergen exposure, itch, and/or watery, stringy discharge.
All forms of allergic conjunctivitis are bilateral. On exam, the conjunctivae are diffusely injected, and there may be chemosis. There may be lid erythema and edema.
INVESTIGATIONS
No definitive test, but generally lacks fluorescein uptake on eye exam.
Bacterial conjunctivitis
SIGNS / SYMPTOMS
Typically presents with a red eye and discharge but without significant pain, photophobia, or changes in vision. There is no history of trauma.
With bacterial conjunctivitis, there may be discomfort, a foreign body sensation, and a mucoid or purulent discharge (if severe, consider gonococcal aetiology). It is often initially unilateral, becoming bilateral. There may be eyelid erythema and oedema. Vision is minimally affected or unaffected. It is not itchy. On exam, the conjunctiva is diffusely injected.
INVESTIGATIONS
No definitive test, but generally lacks fluorescein uptake on eye exam.
Conjunctival swabs for microscopy, culture, and sensitivity may show a bacterial or fungal cause.
Viral conjunctivitis
SIGNS / SYMPTOMS
Typically presents with a red eye and discharge but without significant pain, photophobia, or changes in vision. There is no history of trauma.
With viral conjunctivitis, there may be discomfort, a foreign body sensation, and watery discharge (not purulent) that may be profuse. It is usually initially unilateral, becoming bilateral. There may be associated upper respiratory tract infection symptoms or recent contact with someone with a red eye. Vision is minimally affected or unaffected. On exam, the conjunctiva is diffusely injected. There may be tarsal conjunctival follicles. The cornea may be clear initially, with possible small patches of sub-epithelial infiltrates developing 2 to 3 weeks after onset. Occasionally, pre-auricular lymphadenopathy is present.
INVESTIGATIONS
No definitive test, but generally lacks fluorescein uptake on eye exam.
Use of this content is subject to our disclaimer