Unilateral Red Eye: Causes & Reasons

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Possible Causes for Unilateral Red Eye

Chlamydial Conjunctivitis

red eye. [optometry.org.au]

This 22-year-old white female suffered from an irritated, unilateral (left) red eye for several months. [clspectrum.com]

Signs & Symptoms of Chlamydial Inclusion Conjunctivitis The symptoms and signs of Chlamydia Conjunctivitis include a unilateral (only one eye) red eye, irritation, mucous [mastereyeassociates.com]

Chemical Conjunctivitis

[…] open Corneal opacity Fixed pupil Severe headache with nausea A unilateral red eye. [dermnetnz.org]

Herpes simplex conjunctivitis is usually unilateral. Symptoms include a red eye, photophobia, eye pain and mucoid discharge. [ncemi.org]

These conditions are typically unilateral. Nasolacrimal duct obstruction may produce a discharge, but usually the eye is not red. [clinicaladvisor.com]

Herpes Simplex Keratoconjunctivitis

Primary/recurrent episodes Herpes simplex infection may be either a primary or recurrent episode and usually presents as a unilateral red eye. [healio.com]

Topical latanoprost treatment (for glaucoma). [ 6 ] Symptoms Unilateral in about 88% of cases. (Immunosuppression: more likely to be bilateral.) Red eye. Pain. [patient.info]

Conjunctivitis

The following "red flags" point to other more serious diagnoses, such as keratitis ( inflammation of the cornea ), iritis, or angle closure glaucoma : Unilateral red eye Changes [dermnetnz.org]

The following "red flags" point to other more serious diagnoses, such as keratitis (inflammation of the cornea), iritis, or angle closure glaucoma: Unilateral red eye Changes [dermnetnz.org]

It is usually unilateral. it is the commonest cause of red eye (1) conjunctivitis in children is predominantly bacterial, with nontypeable H. influenzae being the most common [gpnotebook.co.uk]

Viral Conjunctivitis

Viral infection of conjunctiva Commonest reason for acute unilateral red eye Usually caused by adenovirus Usually preceding or concurrent symptoms of upper respiratory infection [kellogg.umich.edu]

The clinical picture is variable but usually features unilateral or bilateral eye involvement with redness, watery discharge, and swelling. [symptoma.com]

A search with fluorescein or another stain (rose bengal or lissamine green) must be done to ensure detection of conjunctival epithelial defect in a moderately red eye. [reviewofoptometry.com]

Scleritis and Episcleritis

red eye, but bilateral in a quarter to a half of cases Mild ache or burning sensation Sometimes tender on palpation Occasionally watery Condition commonly recurrent Signs [college-optometrists.org]

Most patients had unilateral involvement. The ocular symptoms at the initial visit were redness and ocular pain. [karger.com]

Symptoms Patients with episcleritis will report the acute or gradual onset of diffuse or localized eye redness, usually unilateral. [eyewiki.aao.org]

Keratitis Bullosa

Clinical Features It usually presents with a unilateral red eye. Pain is a common feature, which may be disproportionate to the clinical signs. [goodhopeeyeclinic.org.uk]

Keratitis

In the hospitalized patient with a unilateral red eye, always suspect herpes simplex keratitis. [infectiousdiseaseadvisor.com]

Answer and interpretation History: Painful red eye, altered vision, foreign body sensation, photophobia, tearing; usually unilateral Skin (e.g., eyelid) vesicular rash may [lifeinthefastlane.com]

eye Photophobia Signs of keratitis (marginal) Ulcer (stromal infiltrate with overlying epithelial loss) which may be round or arcuate, single or multiple, unilateral or bilateral [college-optometrists.org]

Anterior Uveitis

Conjunctivitis causes watering and discharge from the eye ACUTE ANTERIOR UVEITIS (IRITIS) Presentation * Painful red eye – usually unilateral. * Photophobia and watering of [redorbit.com]

Sudden onset Photophobia Ocular pain Eye redness Non-granulomatous Severe inflammation potentially resulting in: Hypopyon Anterior chamber fibrin Rarely: Papillitis Vitritis [eyewiki.org]

DIAGNOSIS Acute anterior uveitis Supporting points • Unilateral eye pain with photophobia and redness with excessive tearing for duration of 5 days. • Circumcorneal congestion [slideshare.net]

Gonococcal Conjunctivitis

Answer: Bacterial Conjunctivitis 1,2 Presentation and Pathogens: Often begins with unilateral eye redness and crusting +/- irritation/pain. [emdocs.net]

Chlamydial conjunctivitis is often a unilateral disease but can involve both eyes. [webeye.ophth.uiowa.edu]

Herpes simplex conjunctivitis is usually unilateral. Symptoms include a red eye, photophobia, eye pain and mucoid discharge. [intechopen.com]

Foreign Body in the Eye

[…] protection Symptoms Typically unilateral Irritation/foreign body sensation/pain Lacrimation Blurred vision Red eye Signs Foreign body adherent to ocular surface Linear corneal [college-optometrists.org]

Aetiology Patient often gives history of foreign body entering eye wind blown high velocity (hammering, grinding) DIY and gardening Predisposing factors Lack of suitable eye [college-optometrists.org]

Chalazion

It usually presents as an acute onset of unilateral eyelid oedema, with a red and painful eye. [evidence.nhs.uk]

[…] eyelid oedema, with a red and painful eye. [evidence.nhs.uk]

Orbital cellulitis (an infection involving the deep soft tissue surrounding the eyeball, located posterior to the orbital septum) usually presents as an acute onset of unilateral [evidence.nhs.uk]

Iritis

red, painful eye. [bestbets.org]

Signs & Symptoms Acute iritis of sudden onset: Severe eye pain; Sensitivity to light; Eye redness; Smaller pupil in the affected eye (sometimes); Increased tearing. [rxmed.com]

[…] reactive pupils and eye redness. [morancore.utah.edu]

Herpes Simplex Dendritic Keratitis

History Key aspects to inquire about in the history of patients with suspected HSV include past infections (history of recurrent "red eye", particularly unilateral), underlying [eyewiki.aao.org]

Topical latanoprost treatment (for glaucoma). [ 6 ] Symptoms Unilateral in about 88% of cases. (Immunosuppression: more likely to be bilateral.) Red eye. Pain. [patient.info]

Uveitis

Symptoms [ 11 ] Acute anterior uveitis Usually unilateral. Pain, redness and photophobia are typical. Eye pain is often worse when trying to read. [patient.info]

Patients with unilateral anterior uveitis have ocular ache in the affected eye if light is shined in the unaffected eye (true photophobia), which is uncommon in conjunctivitis [merckmanuals.com]

Differential diagnosis Any cause of a red eye or visual disturbance should be included in the differential diagnosis. [patient.info]

Acute Angle Closure Glaucoma

Often, closed angle glaucoma presents acutely as a painful red eye. Reference: (1) European Glaucoma Society (EGS) 2008. [gpnotebook.co.uk]

Frequently associated symptoms include eye redness, headache (classically unilateral and periorbital), nausea, vomiting, and photophobia.[3] Rarely, acute ACG can present [tamingthesru.com]

The condition is frequently bilateral and its incidence increases with age. 90% of acute attacks are unilateral (2). [gpnotebook.co.uk]

Vernal Conjunctivitis

Figure 1 Flow diagram for classification of red eye and its most frequently occurring causes Figure 2 Principal causes of unilateral acute red eye Both eyes should always [aerzteblatt.de]

Symptoms may be mild to severe, with unilateral redness and serous discharge spreading to the second eye one to two days later. [reviewofoptometry.com]

Keratitis : presents with a unilateral, acutely painful, photophobic, injected eye. Scleritis : severe, boring ocular pain, which may radiate to the head and face. [patient.info]

Cluster Headache

Usually unilateral. Deep stabbing pain around the temple or the eye. [diffen.com]

Cluster headaches Deep stabbing pain around the temple or the eye, which is usually on one side (unilateral) Stuffy or runny nose Tearing or redness in eyes, droopy eyelids [belmarrahealth.com]

Stuffy or runny nose Tearing or redness in eyes, droopy eyelids Migraine Moderate to severe, throbbing head pain. [diffen.com]

Subconjunctival Hemorrhage

Presentation Red eye, usually unilateral. It is usually asymptomatic. [patient.info]

Orbital Cellulitis

[…] of eye Unilateral presentation most common +/- fever Physical exam Suggestive of periorbital cellulitis : Conjunctival discharge No vision changes Pronounced edema Suggestive [fprmed.com]

[…] are most common causes H. influenzae now an uncommon agent d/t widespread vaccination Hematogenous spread to periorbital area Rare Hx/signs & symptoms Acute swelling and redness [fprmed.com]

Central Corneal Ulcer

4 More common complaints include redness, pain, pain with eye movements (suggestive of associated scleritis), blurred vision, photophobia and tearing. [ophthalmologymanagement.com]

Presentation - acute unilateral/bilateral exacerbations characterised by decreased visual acuity, with variable pain and redness (there may be none). [patient.info]

Although PUK can be bilateral and extensive, it's more often unilateral or asymmetric in its presentation, and the pathology is limited to one sector of the peripheral cornea [ophthalmologymanagement.com]

Corneal Ulcer

Affected eyes are seen to be red and congested but inflammation does not extend beyond 3 mm from the limbus. [eyewiki.aao.org]

[…] colleagues classified the disease into three types based on clinical features, anterior segment fluorescein angiographic findings, and treatment response [1] : The first type, unilateral [eyewiki.aao.org]

Chemical Burn of the Cornea

Case report A 32-year-old male reported painful discomfort, redness, photophobia, and a decrease in visual acuity in the left eye after a unilateral burn with ammonium defluoridate [dovepress.com]

Exposure Keratitis

Presentation - acute unilateral/bilateral exacerbations characterised by decreased visual acuity, with variable pain and redness (there may be none). [patient.info]

Management - treatment involves systemic immunosuppression, topical immunosuppression, ocular lubricants and globe protection (such as an eye shield). [patient.info]

Chronic Catarrhal Conjunctivitis

The process is usually unilateral. There is a marked redness and swelling of the conjunctiva, serous discharge. [medicalency.com]

The virus is transmitted by contact way, sometimes through eye drops, tools. [medicalency.com]

Epidemic Keratoconjunctivitis

Clinical Pearls Suspect HSV in cases of unilateral adult-onset red eye that is inconsistent with the symptoms (i.e., the patient seems to be in far less discomfort than the [medicalstudy.blogspot.com]

Herpes Simplex Keratitis Signs and Symptoms The keratitis caused by the herpes simplex virus (HSV) typically presents as a unilateral "red eye" with a variable degree of pain [medicalstudy.blogspot.com]

Allergic Conjunctivitis

Keratitis : presents with a unilateral, acutely painful, photophobic, injected eye. Scleritis : severe, boring ocular pain, which may radiate to the head and face. [patient.info]

Episcleritis : mildly uncomfortable acute-onset red segment in one or both eyes. Orbital cellulitis. Foreign body Ocular herpes simplex. Herpes zoster ophthalmicus. [patient.info]

Acute Hemorrhagic Conjunctivitis

[…] of eyes with subconjunctival haemorrhages and epiphora (Fig. 2). 33 Initially unilateral, it becomes bilateral within 24 hours and may persist for 3 - 7 days before spontaneous [samj.org.za]

unilateral at first, becoming bilateral, first eye usually more affected Blurred vision if central cornea involved Systemic malaise Signs Watery discharge Conjunctival hyperaemia [college-optometrists.org]

[…] its spread. 30-32 The disease affects all age groups, is self-limiting and is characterised by abrupt onset of ocular pain, eyelid oedema, foreign body sensation, rash, redness [samj.org.za]

Acute Contagious Conjunctivitis

[…] open Corneal opacity Fixed pupil Severe headache with nausea A unilateral red eye. [dermnetnz.org]

Physical examination Symptoms Red eye: Either unilateral, bilateral, or sequentially bilateral Discharge: Classically purulent, but may be thin or thick muco-purulent or watery [eyewiki.aao.org]

Chlamydial conjunctivitis is often a unilateral disease but can involve both eyes. [webeye.ophth.uiowa.edu]

Eyeball Injury

An extreme eye injury can cause a globe rupture where the eyeball can split open. This can be due to trauma directly on the eye or around the eye. Watch this episode of A State of Sight with Isaac Porter, MD to learn more about this injury and the eye surgery options to help save the eye and restore vision.[…] [eyeporter.com]