Conjunctivitis (bacterialMANAGEMENT

INFECTIOUS DISEASE PRESENTATIONS · 12 SECTIONS

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486 items

☷ Legend

01Approach to the Critical Patient/attcp54

Red flags and immediate escalation

›Immediate threat screen

›Vision loss

›Decreased visual acuity compared with baseline

›New afferent pupillary defect

›Severe ocular pain

›Disproportionate pain for conjunctivitis pattern

›Pain with extraocular movements

›Photophobia

›Consensual photophobia

›Marked ciliary flush

›Corneal involvement

›Corneal opacity

›Corneal epithelial defect on fluorescein

›Proptosis

›Orbital cellulitis concern

›Increased intraorbital pressure concern

›Elevated intraocular pressure pattern

›Mid-dilated fixed pupil pattern

›Halos and headache pattern

›Contact lens wearer with pain

›Bacterial keratitis concern

›Pseudomonas risk

›Immunocompromised state

›Atypical infection concern

›HSV and fungal keratitis concern

›Neonate with conjunctivitis

›Gonococcal and chlamydial risk

›Systemic infection risk

›Chemical exposure

›Alkali injury concern

›Urgent irrigation pathway

›Immediate actions if red flags present

›If chemical exposure, initiate irrigation immediately

›Morgan lens if available

›Continue until ocular surface pH neutral

›If vision threatened, urgent ophthalmology

›Corneal ulcer concern

›HSV keratitis concern

›If orbital cellulitis concern, initiate systemic antibiotics and imaging pathway

›CT orbit with contrast pathway

›Admission pathway

Triage classification

›Working diagnosis group

›Simple conjunctivitis pattern

›Mild discomfort

›Normal visual acuity

›Keratitis or uveitis pattern

›Photophobia

›Corneal findings or anterior chamber findings

›Preseptal cellulitis pattern

›Eyelid erythema and edema

›Full extraocular movements

›Orbital cellulitis pattern

›Pain with extraocular movements

›Proptosis or diplopia

02History/hx55

Symptom pattern and exposures

›Key history elements

›Laterality and timeline

›Unilateral onset with spread to other eye

›Sudden onset after exposure

›Discharge character

›Watery

›Mucopurulent

›Itch prominence

›Seasonal triggers

›Atopy history

›Contact lens use

›Overnight wear

›Water exposure with lenses

›Viral exposure and systemic symptoms

›Upper respiratory infection

›Sick contacts

›Recent ocular trauma or foreign body

›High-velocity risk

›Organic material exposure

›Chemical exposure details

›Alkali versus acid

›Time to irrigation

›Sexually transmitted infection risk

›Urethritis or cervicitis symptoms

›New partner exposure

›Medication and topical exposure

›New eye drops

›Preservative sensitivity

›Immunocompromise

›HIV

›Chemotherapy

›Neonatal context

›Day of life at onset

›Maternal STI history

Classic syndromes and pitfalls

›Phenotype clues

›Viral conjunctivitis pattern

›Watery discharge

›Gritty sensation

›Preauricular lymphadenopathy

›Bacterial conjunctivitis pattern

›Mucopurulent discharge

›Eyelids stuck shut on waking

›Minimal itch

›Allergic conjunctivitis pattern

›Intense itch

›Bilateral symptoms

›Clear watery discharge

›HSV ocular disease pattern

›Unilateral pain

›Recurrent episodes history

›Vesicular lid lesions history

›Gonococcal conjunctivitis pattern

›Hyperacute onset hours to 1 day

›Copious purulent discharge

›Rapid corneal involvement risk

03Physical Exam/exam44

Eye exam essentials

›Core exam elements

›Visual acuity

›Each eye separately

›Pinhole if reduced

›Pupils

›Afferent pupillary defect

›Anisocoria pattern

›Extraocular movements

›Pain with movement

›Diplopia

›External and lids

›Lid edema pattern

›Vesicles

›Conjunctiva and sclera

›Diffuse conjunctival injection

›Ciliary flush

›Discharge and tear film

›Watery versus mucopurulent

›Crusting

›Cornea

›Opacity or infiltrate

›Fluorescein uptake pattern

›Anterior chamber

›Cells and flare pattern

›Hypopyon

›Preauricular nodes

›Tender lymphadenopathy

›Unilateral predominance

Pitfalls and high-risk findings

›Findings inconsistent with simple conjunctivitis

›Marked photophobia

›Anterior uveitis concern

›Keratitis concern

›Corneal epithelial defect

›Ulcer risk

›Contact lens keratitis risk

›Proptosis

›Orbital cellulitis concern

›Cavernous sinus process concern

›Limited extraocular movements

›Orbital cellulitis concern

›Myositis concern

›Elevated intraocular pressure pattern

›Acute angle closure glaucoma concern

›Urgent ophthalmology pathway

04Differential Diagnosis/ddx38

Vision-threatening and must-not-miss

›High-risk alternatives

›Keratitis

›Bacterial keratitis

›HSV keratitis

›Anterior uveitis

›Photophobia dominant

›Small irregular pupil pattern

›Acute angle closure glaucoma

›Headache and nausea pattern

›Mid-dilated fixed pupil pattern

›Scleritis

›Deep boring pain

›Pain with eye movement

›Orbital cellulitis

›Proptosis

›Ophthalmoplegia

›Endophthalmitis

›Recent ocular surgery

›Severe pain with vision loss

Common mimics and coding anchors

›Common mimics

›Dry eye disease

›Foreign body sensation

›Worse with screens

›Blepharitis

›Lid margin debris

›Recurrent irritation

›Nasolacrimal duct obstruction

›Tearing predominant

›Medial canthal reflux

›Foreign body

›Focal discomfort

›Upper lid tarsal foreign body

›ICD-10 anchors

›Acute conjunctivitis unspecified H10.30

›Mucopurulent conjunctivitis H10.02

›Viral conjunctivitis H10.9 or H10.30 depending on documentation

›Allergic conjunctivitis H10.1

›Chronic conjunctivitis H10.4

05Laboratory Tests/lt30

When testing is needed

›Testing indications

›Severe purulent discharge

›Hyperacute gonococcal concern

›Culture and NAAT pathway

›Neonatal conjunctivitis

›Gonorrhea and chlamydia testing

›Sepsis evaluation if ill-appearing

›Immunocompromised host

›Atypical pathogens concern

›Low threshold for culture

›Recurrent or non-resolving symptoms

›Resistant bacterial concern

›Alternative diagnosis concern

Microbiology

›Pathogen tests

›Conjunctival swab culture

›Hyperacute purulence

›Failure of initial therapy

›NAAT for chlamydia and gonorrhea

›STI risk history

›Neonatal evaluation

›HSV testing

›Vesicular lesions

›Dendritic fluorescein pattern

Systemic labs when complications suspected

›Systemic evaluation

›CBC for orbital cellulitis concern

›Leukocytosis support

›Baseline for admission

›Blood cultures for toxic appearance

›Orbital cellulitis with systemic features

›Neonatal systemic illness concern

06Diagnostic Tests/dt36

Scoring Systems

›Decision support concepts

›No validated ED scoring system for conjunctivitis etiology

›Clinical phenotype predominance

›Red flag based escalation

›Orbital cellulitis clinical criteria cluster

›Pain with extraocular movements

›Ophthalmoplegia

›Proptosis

›Decreased visual acuity

MRI

›MRI indications

›Cavernous sinus thrombosis concern

›Cranial nerve palsies pattern

›Severe headache and fever pattern

›Intracranial extension concern

›Altered mental status

›Focal neurologic deficits

›Complicated orbital infection

›Subperiosteal abscess concern

›Poor CT correlation with exam

›CT orbit and sinuses

›Indications

›Orbital cellulitis concern

›Subperiosteal abscess concern

›Technique

›Contrast enhanced orbit CT preferred for cellulitis evaluation

›Sinus assessment for source control planning

›Findings supporting orbital cellulitis

›Postseptal fat stranding

›Abscess collection

Ultrasound (or US)

›Point-of-care ultrasound roles

›Preseptal edema versus abscess screening

›Subcutaneous cobblestoning pattern

›Fluid collection pattern

›Ocular ultrasound contraindication reminders

›Suspected globe rupture

›Severe pain with trauma mechanism

07Disposition/dispo22

Outpatient versus urgent referral

›Disposition pathways

›Routine outpatient care

›Normal visual acuity

›Mild discomfort only

›No corneal findings

›Same-day ophthalmology or ED return precautions reinforced

›Contact lens wearer with pain

›Photophobia

›Decreased vision

›ED observation or admission

›Orbital cellulitis concern

›Systemic toxicity

›Immediate specialty involvement

›Suspected HSV keratitis

›Suspected gonococcal conjunctivitis

›Follow-up timing

›Reassessment window for bacterial treatment trial

›Worsening after 24 to 48 hours

›No improvement by 48 to 72 hours

›Allergic symptom persistence

›Consider allergen control plan

›Consider ophthalmology if severe or chronic

08Treatment/t90

Supportive care for all types

›Supportive measures

›Lubricating drops

›Preservative-free artificial tears

›Frequent dosing as needed

›Cool compresses

›Itch and swelling reduction

›Avoid shared towels

›Contact lens holiday

›Stop lenses until symptoms resolved

›Replace lenses and case after infection

›Infection control

›Hand hygiene

›Avoid sharing cosmetics

Bacterial conjunctivitis

›Empiric topical antibiotics

›First-line options for uncomplicated cases

›Trimethoprim polymyxin B drops

›1 drop every 6 hours

›Duration 5 to 7 days

›Erythromycin ophthalmic ointment

›1 cm ribbon 4 times daily

›Duration 5 to 7 days

›Bacitracin ophthalmic ointment

›1 cm ribbon 4 times daily

›Duration 5 to 7 days

›Contact lens associated coverage

›Fluoroquinolone drops

›Moxifloxacin 0.5 percent

›1 drop 3 times daily

›Duration 5 to 7 days

›Ciprofloxacin 0.3 percent

›1 to 2 drops every 2 hours while awake for 2 days

›Then 1 to 2 drops every 4 hours while awake for 5 days

›Severe purulence or hyperacute onset

›Gonococcal pathway

›Ceftriaxone IM or IV 1 g single dose

›If corneal involvement, ophthalmology and admission pathway

›Saline irrigation to clear discharge

›Chlamydia coinfection coverage

›Doxycycline 100 mg orally every 12 hours for 7 days

›If pregnancy or doxycycline contraindication, azithromycin 1 g orally single dose

›Evidence notes

›Uncomplicated bacterial conjunctivitis often self-limited

›Antibiotics shorten symptom duration modestly

›Shared decision-making for mild cases

Viral conjunctivitis

›Adenoviral pattern management

›Supportive care only

›Artificial tears

›Cool compresses

›Return precautions for keratitis signs

›Increasing photophobia

›Vision decrease

›HSV ocular disease

›HSV keratitis concern triggers ophthalmology

›Dendritic fluorescein uptake pattern

›Decreased corneal sensation pattern

›Antiviral options when HSV suspected and ophthalmology plan established

›Oral acyclovir

›400 mg orally 5 times daily

›Duration 7 to 10 days

›Oral valacyclovir

›500 mg orally every 12 hours

›Duration 7 to 10 days

›Steroid avoidance without ophthalmology

›Risk of worsening HSV keratitis

›Risk of corneal melt in ulcers

Allergic conjunctivitis

›Allergen-directed therapy

›Topical antihistamine or mast cell stabilizer

›Olopatadine 0.1 percent

›1 drop every 12 hours

›Use for seasonal symptoms

›Ketotifen 0.025 percent

›1 drop every 8 to 12 hours

›Over-the-counter option in some regions

›Oral antihistamines

›Cetirizine 10 mg orally daily

›Sedation risk counseling

›Dry eye worsening risk

›Severe chemosis or refractory symptoms

›Ophthalmology referral for steroid consideration

›Intraocular pressure monitoring need

›Infection exclusion prior to steroid

Medication safety and guideline framing

›Guideline and evidence framing

›ACEP Level C

›Topical antibiotics reasonable for suspected bacterial conjunctivitis when follow-up uncertain

›Contact lens wearers require pseudomonal coverage and close follow-up

›Class I

›Immediate irrigation for chemical ocular exposure

›Ophthalmology involvement for suspected corneal ulcer or HSV keratitis

›Class IIa

›Empiric fluoroquinolone drops for contact lens associated conjunctivitis symptoms with pain

09Special Populations/sp40

Pregnancy

›Pregnancy considerations

›Medication selection

›Erythromycin ophthalmic ointment preferred safety profile

›Avoid systemic tetracyclines

›STI related conjunctivitis

›Chlamydia treatment with azithromycin option

›Partner notification and treatment pathway

›Red flags unchanged

›Vision changes require urgent evaluation

›Photophobia requires keratitis or uveitis exclusion

Geriatric

›Geriatric considerations

›Baseline ocular disease prevalence

›Dry eye disease common mimic

›Blepharitis contribution common

›Higher stakes for vision changes

›Glaucoma risk

›Herpetic eye disease recurrence risk

›Medication tolerability

›Preservative irritation risk

›Prefer preservative-free lubricants when frequent dosing

Pediatrics

›Pediatric considerations

›Etiology distribution

›Viral common in school outbreaks

›Allergic common with atopy

›School and daycare considerations

›Symptom-based return guidance

›Hygiene reinforcement

›Topical dosing practicality

›Ointment easier administration for younger children

›Drop technique coaching for caregivers

›Neonatal conjunctivitis

›Day 0 to 2 onset pattern

›Chemical conjunctivitis possible

›Supportive care after exclusion of infection

›Day 2 to 5 onset pattern

›Gonococcal concern

›Ceftriaxone pathway and admission consideration

›Day 5 to 14 onset pattern

›Chlamydial concern

›Systemic macrolide therapy pathway

10Background/b37

Epidemiology

›Epidemiology overview

›Viral conjunctivitis

›Most common infectious conjunctivitis overall

›Adenovirus common cause

›Bacterial conjunctivitis

›More common in children than adults

›Self-limited course common

›Allergic conjunctivitis

›Seasonal prevalence in atopic patients

›Often recurrent pattern

Pathophysiology

›Mechanisms

›Viral

›Conjunctival epithelial infection

›Follicular response and watery discharge

›Bacterial

›Neutrophilic inflammation

›Mucopurulent discharge and crusting

›Allergic

›IgE mediated mast cell activation

›Histamine driven itch and chemosis

›Contact lens risk

›Microtrauma to epithelium

›Pseudomonas keratitis risk

Therapeutic Considerations

›Rationale and tradeoffs

›Antibiotics

›Benefit greatest in moderate to severe purulence

›Reduced symptom duration in some trials

›Resistance pressure with unnecessary use

›Fluoroquinolones

›Pseudomonas coverage for contact lens risk

›Reserve for higher-risk presentations

›Antihistamine mast cell stabilizers

›Rapid itch relief

›Prevention with regular use during season

›Steroids

›Avoid without ophthalmology in infectious presentations

›Intraocular pressure rise risk

11Patient Discharge Instructions/pdi27

copy discharge instructions

›Discharge instructions

›Diagnosis explanation

›Conjunctivitis types include viral, bacterial, allergic

›Most cases improve with supportive care

›Medication use

›Drops and ointment technique

›Complete prescribed course if antibiotics started

›Contact lens guidance

›No contact lenses until symptoms fully resolved

›Replace lenses and case after infection

›Hygiene

›Hand washing after touching eyes

›Do not share towels, pillows, or eye makeup

›Replace eye makeup after infection

›Symptom control

›Cool compresses

›Artificial tears as needed

›Return to ED now

›Vision worse

›Moderate or severe eye pain

›Light sensitivity

›New severe headache, vomiting, or halos around lights

›Swelling around eye with pain on eye movement

›Contact lens wearer with pain or worsening redness

›Follow-up

›If not improving in 48 to 72 hours

›Earlier follow-up for contact lens wearers

12References/r13

Guidelines and evidence sources

›Core references

›American Academy of Ophthalmology conjunctivitis guidance and preferred practice patterns

›Hygiene and supportive care for viral conjunctivitis

›Steroid avoidance without specialist evaluation for suspected infection

›Systematic reviews of topical antibiotics for acute bacterial conjunctivitis

›Modest reduction in time to clinical cure

›High spontaneous resolution rates

›STI guidelines for gonococcal and chlamydial conjunctivitis treatment

›Ceftriaxone systemic therapy for gonococcal infection

›Systemic therapy for chlamydial infection

›Emergency medicine consensus recommendations

›Imaging and admission criteria for orbital cellulitis concern

›Contact lens wear as keratitis risk trigger

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed June 16, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.