Birdshot chorioretinopathy

What it is

From: Orphanet

Birdshot chorioretinopathy is a posterior uveitis characterized by multiple cream-colored, hypopigmented choroidal lesions in the fundus and a strong association with HLA-A29 and clinically presenting with blurred vision, floaters, photopsia, scotoma and nyctalopia.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abnormal choroid morphology · Very frequent (99-80%)

Any structural abnormality of the choroid (the posterior part of the uvea, the middle tunic of the eye, consisting mainly of blood vessels).

Abnormal retinal vascular morphology · Very frequent (99-80%)

A structural abnormality of retinal vasculature.

Chorioretinal abnormality · Very frequent (99-80%)

An abnormality of the choroid and retina.

Cystoid macular edema · Very frequent (99-80%)

Cystoid thickening of the retina that takes place due to accumulation of extracellular fluid in the macula as a nonspecific response to blood-retinal barrier breakdown. Histological studies show that radially orientated cystoid spaces consisting of ophthalmoscopically clear fluid are often clinically detectable in the macula area.

Ocular hypertension · Very frequent (99-80%)

Intraocular pressure that is 2 standard deviations above the population mean.

Photoreceptor layer loss on macular OCT · Very frequent (99-80%)

Loss of the outer nuclear layer (photoreceptor layer) as assessed by ocular coherence tomography.

Visual loss · Very frequent (99-80%)

Loss of visual acuity (implying that vision was better at a certain time point in life). Otherwise the term reduced visual acuity should be used (or a subclass of that).

Vitritis · Very frequent (99-80%)

Inflammation of the vitreous body, characterized by the presence of inflammatory cells and protein exudate in the vitreous cavity.

Attenuation of retinal blood vessels · Frequent (79-30%)

Narrowing of the retinal blood vessels, both arterioles and venules.

Blurred vision · Frequent (79-30%)

Lack of sharpness of vision resulting in the inability to see fine detail.

Cataract · Frequent (79-30%)

A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule.

Epiretinal membrane · Frequent (79-30%)

An epiretinal membrane is a thin sheet of fibrous tissue on the surface of the retina along the inner limiting membrane. It appears as a greyish semi-translucent avascular membrane over the internal limiting membrane (ILM) on the surface of the retina.

Inflammatory abnormality of the eye · Frequent (79-30%)

Inflammation of the eye, parts of the eye or the periorbital region.

Macular hole · Frequent (79-30%)

A macular hole is a full thickness gap in the macula, located in the center of the retina.

Other findings in the same source

From: Orphanet

Additional reported features include Macular scar (Frequent (79-30%)); Optic disc pallor (Frequent (79-30%)); Photophobia (Frequent (79-30%)); Retinal thinning (Frequent (79-30%)); Vitreous floaters (Frequent (79-30%)); Blind-spot enlargment (Frequent (79-30%)); Choroidal neovascularization (Occasional (29-5%)); Retinal detachment (Occasional (29-5%)); Arcuate scotoma (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adult; Elderly

Inheritance in the source

From: Orphanet

Unknown

Frequency and the population described

From: Orphanet

Point prevalence: 1-9 / 1 000 000; Worldwide; Value and class. Point prevalence: 1-9 / 1 000 000; United States; Value and class.

Which doctor should you see?

The suggested department for discussing Birdshot chorioretinopathy is Ophthalmology, with a ophthalmologist as the relevant type of clinician. Ophthalmologist; paediatric services for children as appropriate.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which part of the eye or visual pathway is affected?
• What change in vision requires immediate contact with the eye service?
• What are the aims and alternatives of any proposed eye treatment?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Birdshot chorioretinopathy. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.