- Published on
Ophthalmology – Serpiginous Choroiditis
What the Disorder Represents
Serpiginous choroiditis (SC) is a rare, chronic, recurrent inflammatory chorioretinopathy primarily involving the:
- Choriocapillaris
- Retinal pigment epithelium (RPE)
- Outer retina
- Deeper choroid to a variable degree
The classic lesion begins near the:
Optic disc
and extends outward in an irregular, geographic or snake-like pattern.
Disease is usually:
- Bilateral
- Asymmetric
- Recurrent
- Potentially progressive
Vision is threatened mainly when inflammation involves the:
- Fovea
- Papillomacular region
or when secondary:
Choroidal neovascularization (CNV) develops.
Who Usually Develops It
Serpiginous choroiditis is uncommon and represents only a small proportion of posterior uveitis cases.
It most often affects:
- Young to middle-aged adults
- Men somewhat more frequently in many reported series
There is no consistent:
- Familial pattern
- Racial predilection
Prevalence appears higher in some regions, particularly parts of:
South Asia
where tuberculosis-associated serpiginous-like choroiditis must be carefully considered.
How the Inflammation Behaves
The inflammatory process primarily targets the:
Choriocapillaris–RPE–outer retinal complex
leading to:
- Choriocapillaris nonperfusion
- RPE dysfunction
- Photoreceptor injury
- Subsequent chorioretinal atrophy
Repeated inflammatory episodes produce:
Progressive geographic scars
that frequently extend from the edges of previous lesions.
What Causes It
The exact cause of classic serpiginous choroiditis remains:
Unknown
It is generally regarded as an:
Immune-mediated inflammatory choriocapillaropathy
However, a major modern diagnostic issue is that a similar phenotype can occur with infection, especially:
Mycobacterium tuberculosis
This infectious form is generally termed:
Serpiginous-like choroiditis
rather than classic autoimmune serpiginous choroiditis.
Why Tuberculosis Matters
Tubercular serpiginous-like choroiditis is particularly important in:
- TB-endemic regions
- Patients with TB exposure
- Patients with positive TB testing
- Multifocal or atypical lesions
Treating undiagnosed infectious disease with immunosuppression alone can:
Worsen infection
so infectious causes must be considered before prolonged immunomodulatory treatment.
Genetic Associations
No causative genetic mutation has been established.
Certain HLA associations have been reported, including:
- HLA-B7 in some populations
but these findings are:
Not used routinely for diagnosis.
Typical Symptoms
Patients commonly notice:
- Painless blurred vision
- Metamorphopsia
- Paracentral or central scotoma
- Reduced contrast
- Photopsias
Symptoms are often initially:
Unilateral
even though the fellow eye may later become involved.
Pattern of Recurrence
The disease is characteristically:
Chronic and relapsing
Recurrences often develop:
- At the advancing edge of an old lesion
- Adjacent to previous scars
and may occur after intervals of:
- Weeks
- Months
- Years
Repeated attacks can progressively enlarge the area of:
Chorioretinal atrophy.
What the Anterior Segment Usually Looks Like
The anterior segment is often:
Quiet
although mild anterior chamber inflammation may occasionally occur.
Likewise, vitreous inflammation is generally:
- Minimal
- Mild
Marked vitritis should prompt consideration of another diagnosis, particularly:
- Tubercular serpiginous-like disease
- Multifocal choroiditis
- Infectious posterior uveitis
Classic Peripapillary Form
The most typical form is:
Peripapillary geographic serpiginous choroiditis
Lesions begin adjacent to the optic disc and extend centrifugally in:
- Geographic
- Irregular
- Serpentine
patterns.
Appearance of Active Disease
Active lesions are usually:
- Gray-white
- Cream-colored
- Deep retinal/choroidal
and occur at the:
Leading edge of previously inactive scar
They may appear relatively subtle clinically despite significant choriocapillaris inflammation on imaging.
Appearance After Healing
Healed lesions leave:
- RPE atrophy
- Choroidal atrophy
- Hyperpigmented borders
- Hypopigmented central scar
The resulting lesion may appear:
Geographic and sharply demarcated.
Why Recurrences Are Easy to Recognize
A highly characteristic pattern is:
New creamy active border surrounding or extending from an older pigmented atrophic lesion
This reflects reactivation along the margin of previously affected tissue.
Macular Serpiginous Choroiditis
A less common variant begins in the:
Macula
without direct continuity with the optic disc.
This form has a worse visual prognosis because:
- Foveal involvement occurs early
- CNV risk is higher
- Scar formation directly affects central vision
Amphiginous Choroiditis
Amphiginous choroiditis describes a phenotype with overlapping features of:
- APMPPE
- Serpiginous choroiditis
Patients may initially present with multiple placoid lesions and subsequently develop:
- Recurrent
- Progressive
- Serpiginous-like extension
This entity is often considered within the broader spectrum of:
Placoid inflammatory chorioretinopathies.
Relentless Placoid Chorioretinitis
Relentless placoid chorioretinitis (RPC) is characterized by:
- Numerous placoid lesions
- Involvement extending from posterior pole to far peripheral retina
- Prolonged or recurrent disease course
It differs from classic serpiginous choroiditis by its:
- Much greater number of lesions
- Wider retinal distribution
- More prolonged inflammatory activity
Tubercular Serpiginous-Like Choroiditis
This form may differ from classic SC by showing:
- Multifocal lesions
- More peripheral involvement
- Greater vitritis
- Less strict peripapillary origin
- More prominent inflammation
However, overlap is substantial.
Diagnosis depends on combining:
- Clinical appearance
- TB exposure/risk
- IGRA or other testing
- Chest imaging
- Systemic assessment
No single test proves ocular TB in every case.
Establishing the Diagnosis
Diagnosis is primarily:
Clinical plus multimodal imaging
There is no single laboratory marker for classic serpiginous choroiditis.
Important goals are to:
- Confirm active choriocapillaris/RPE disease
- Identify foveal involvement
- Detect CNV
- Exclude infection, especially TB and syphilis
Fundus Photography
Color or wide-field photography is useful to document:
- Lesion borders
- Active extension
- Atrophic scars
- Recurrence patterns
Serial images can help demonstrate:
Centrifugal expansion from old lesions.
Fundus Autofluorescence
FAF is particularly useful for identifying activity and monitoring progression.
Active lesions may show:
- Early hypoautofluorescence
- Followed by hyperautofluorescent borders or mixed patterns
Healing lesions become:
Hypoautofluorescent
as RPE atrophy develops.
FAF often reveals lesion activity more clearly than clinical examination alone.
Fluorescein Angiography
Active lesions typically demonstrate:
- Early hypofluorescence
- Late staining or hyperfluorescence
Early hypofluorescence reflects:
- Choriocapillaris nonperfusion
- Blockage by inflammatory material
Late hyperfluorescence reflects:
- Staining
- RPE alteration
- Leakage at active margins
Angiographic Appearance of Old Scars
Inactive atrophic lesions generally show:
- Early transmission hyperfluorescence
- Late staining
depending on the degree of:
- RPE loss
- Choroidal atrophy
Indocyanine Green Angiography
ICGA is particularly sensitive for:
Choroidal and choriocapillaris involvement
Active lesions usually appear as:
- Persistent hypofluorescent areas
and may extend beyond the clinically visible lesion.
This can help determine:
True extent of inflammatory activity.
Optical Coherence Tomography
OCT is essential for assessing:
- Outer retinal disruption
- Ellipsoid-zone loss
- RPE abnormalities
- Subretinal hyperreflective material
- Retinal thinning after healing
- Secondary CNV
OCT During Active Disease
Active lesions may show:
- Hyperreflectivity of outer retinal layers
- Disruption of the ellipsoid zone
- RPE irregularity
- Outer retinal thickening
As inflammation resolves:
- Outer retinal thinning
- RPE atrophy
- Photoreceptor loss
may remain.
OCT Angiography
OCTA may help demonstrate:
- Choriocapillaris flow deficits
- Secondary CNV
It is particularly useful when CNV is suspected but hemorrhage or inflammation complicates conventional angiographic interpretation.
However:
OCTA does not show leakage, so it complements rather than replaces FA.
Visual Field Changes
Visual field defects correspond to areas of chorioretinal damage.
Patients may develop:
- Paracentral scotomas
- Enlarged blind spot
- Central scotoma
- Irregular field loss
Some scotomas may become less dense after active inflammation resolves, but permanent defects can remain after atrophy.
Laboratory Evaluation Strategy
Classic SC has no diagnostic blood test.
Testing is directed toward excluding:
- Tuberculosis
- Syphilis
- Other infectious/inflammatory mimics
rather than confirming idiopathic serpiginous disease.
Tuberculosis Evaluation
Depending on local prevalence and clinical suspicion, evaluation may include:
- IGRA
- Tuberculin skin testing
- Chest X-ray
- Chest CT when needed
A positive IGRA indicates sensitization to TB but does:
Not by itself prove ocular TB.
Syphilis Screening
Syphilis should be excluded because it can mimic virtually any posterior uveitis pattern.
Testing usually includes:
- Treponemal test
- Nontreponemal test
When Additional Systemic Evaluation Is Needed
Further testing may be considered when clinical features suggest:
- Sarcoidosis
- Autoimmune disease
- Other infectious choroiditis
Broad indiscriminate laboratory panels are generally less useful than:
Targeted investigations based on phenotype.
Disorders That Can Look Similar
Important differentials include:
- Tubercular serpiginous-like choroiditis
- APMPPE
- Relentless placoid chorioretinitis
- Multifocal choroiditis
- Toxoplasmosis
- Syphilis
- Sarcoidosis
- Choroidal ischemia
- VKH
- Posterior placoid syphilitic chorioretinitis
Distinguishing It From APMPPE
Serpiginous Choroiditis
- Chronic
- Recurrent
- Often starts peripapillary
- Expands from old scars
- More likely to require prolonged immunosuppression
APMPPE
- Usually acute
- Multiple placoid lesions
- Often self-limited
- Commonly follows viral prodrome
- Recurrence less typical
Distinguishing It From Tubercular Serpiginous-Like Disease
Classic Serpiginous Choroiditis
- Usually peripapillary origin
- Minimal vitritis
- Recurrent edge progression
- Immune-mediated
Tubercular Serpiginous-Like Choroiditis
- Often multifocal
- May involve peripheral retina
- More vitritis
- Associated TB evidence
- Requires antituberculous treatment
Primary Goal of Treatment
The central objective is:
Stop active lesion expansion before the fovea becomes involved and prevent recurrent inflammation.
Because permanent chorioretinal atrophy develops after each episode:
Delayed treatment can produce irreversible visual loss.
Corticosteroid Treatment
Active noninfectious serpiginous choroiditis is commonly treated initially with:
Systemic corticosteroids
especially when lesions threaten:
- Fovea
- Papillomacular bundle
High-dose oral prednisone is commonly used.
Severe or rapidly progressive disease may require:
IV methylprednisolone
for rapid suppression.
Why Steroid Monotherapy Is Often Insufficient
Although corticosteroids can suppress acute activity:
Relapses are common during tapering or after discontinuation.
Therefore recurrent, bilateral, or vision-threatening disease frequently requires:
Early steroid-sparing immunomodulatory therapy.
Long-Term Immunomodulatory Therapy
Common agents include:
- Mycophenolate mofetil
- Methotrexate
- Azathioprine
- Cyclosporine
Choice depends on:
- Disease severity
- Comorbidities
- Treatment response
- Specialist experience
Biologic Therapy
Refractory disease may occasionally require biologic therapy such as:
- Adalimumab
- Infliximab
usually under management by:
- Uveitis specialist
- Rheumatologist
Evidence is less extensive than for more common uveitic disorders, but biologics can be useful in difficult recurrent disease.
Role of Alkylating Agents
Older treatment protocols used:
- Cyclophosphamide
- Chlorambucil
These agents can control severe disease but are now used much less often because of:
- Bone marrow toxicity
- Infertility
- Secondary malignancy risk
- Other serious adverse effects
Local Steroid Therapy
Periocular or intravitreal corticosteroid can reduce local inflammation, but:
Local therapy alone is generally inadequate for bilateral recurrent serpiginous choroiditis.
It may be used selectively as adjunctive treatment.
Managing Tubercular Serpiginous-Like Choroiditis
If tuberculosis is suspected or confirmed, management generally requires:
Appropriate multidrug antituberculous therapy
with infectious-disease or respiratory-medicine collaboration.
Corticosteroids may be added to control ocular inflammation but should generally be used:
Alongside appropriate antimicrobial therapy, not as isolated treatment.
Treating Choroidal Neovascularization
Secondary CNV is an important cause of visual loss.
Modern first-line treatment is:
Intravitreal anti-VEGF therapy
such as:
- Aflibercept
- Ranibizumab
- Bevacizumab
Simultaneous control of active underlying inflammation is also important.
How CNV Presents
Suspect CNV with:
- New metamorphopsia
- New central blur
- Subretinal hemorrhage
- New subretinal/intraretinal fluid
- Hyperreflective neovascular complex on OCT
OCTA and FA can help confirm the diagnosis.
Monitoring During Active Disease
Active lesions require:
Frequent follow-up
because progression toward the fovea can occur quickly.
Monitoring commonly uses:
- Visual acuity
- OCT
- FAF
- Fundus photography
- FA/ICGA when needed
Monitoring During Remission
Even apparently inactive disease requires long-term surveillance because:
Recurrences can occur months or years later.
Patients should report promptly:
- New scotoma
- Metamorphopsia
- Blurred vision
- New photopsias
Expected Long-Term Course
The disease is typically:
Chronic and recurrent
with progressive chorioretinal scarring.
Some patients maintain good vision if:
- Fovea remains uninvolved
- Recurrences are rapidly controlled
Others develop substantial central visual loss through:
- Foveal atrophy
- CNV
- Repeated inflammatory damage
Features Associated With Worse Vision
Poorer prognosis is associated with:
- Macular involvement
- Repeated recurrences
- Delayed suppression of active lesions
- Secondary CNV
- Bilateral progressive disease
Macular serpiginous disease generally carries a worse prognosis than classic peripapillary disease.
Long-Term Complications
Potential complications include:
- Choroidal neovascularization
- Foveal chorioretinal atrophy
- Subretinal fibrosis
- Serous retinal detachment
- Cystoid macular edema
- Retinal vasculitis
- Branch retinal vein occlusion
- Rare anterior uveitis
- Permanent central scotoma
High-Yield Takeaways
- Serpiginous choroiditis is a chronic recurrent inflammatory choriocapillaropathy involving the choriocapillaris, RPE, and outer retina.
- The classic lesion begins peripapillary and spreads centrifugally in a geographic or serpentine pattern.
- Recurrences typically occur at the active edge of an old chorioretinal scar.
- The anterior segment is often quiet and vitreous inflammation is usually mild.
- Macular involvement and secondary CNV are the major threats to central vision.
- Multimodal imaging is essential: FAF, OCT, FA, and ICGA are particularly useful for detecting activity and defining lesion extent.
- Active lesions usually show early hypofluorescence and late staining/hyperfluorescence on FA.
- ICGA commonly demonstrates persistent hypofluorescence corresponding to choriocapillaris involvement.
- OCT shows active outer retinal/RPE disruption and later permanent outer retinal atrophy.
- One of the most important modern distinctions is between classic autoimmune serpiginous choroiditis and tubercular serpiginous-like choroiditis.
- TB-associated disease is especially relevant in endemic regions and should be considered before starting prolonged immunosuppression.
- A positive TB test supports exposure but does not by itself establish ocular tuberculosis.
- Active noninfectious disease generally requires prompt systemic corticosteroid therapy.
- Because recurrences are common with steroid tapering, recurrent or vision-threatening disease often requires steroid-sparing immunomodulatory therapy, such as mycophenolate, methotrexate, azathioprine, or cyclosporine.
- Tubercular serpiginous-like choroiditis requires appropriate antituberculous therapy, with corticosteroid added when needed for inflammatory control.
- Secondary CNV is treated primarily with intravitreal anti-VEGF therapy while controlling the underlying inflammation.
- Long-term surveillance is essential because recurrence may occur months or years after apparent quiescence.
- The final visual outcome depends mainly on whether recurrent inflammation or CNV damages the fovea.
