What are the key components of a physical exam for bacterial conjunctivitis?

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Physical Examination of Bacterial Conjunctivitis

The physical examination for bacterial conjunctivitis should include visual acuity assessment, external examination, and slit-lamp biomicroscopy with particular attention to purulent discharge, conjunctival injection, and absence of corneal involvement. 1

Initial Assessment

Visual Acuity

  • Document baseline visual acuity
  • Note: Visual acuity may be compromised by patient discomfort, tearing, and inflammation 1
  • Ensure consistency with anterior segment examination findings

External Examination

Eyelids and Adnexae

  • Check for swelling, discoloration, malposition
  • Assess for ulceration, nodules, ecchymosis
  • Look for lateral flare and lash loss

Regional Lymphadenopathy

  • Particularly examine for preauricular lymphadenopathy 1

Skin

  • Evaluate for signs of associated conditions:
    • Rosacea
    • Eczema
    • Seborrhea

Slit-Lamp Biomicroscopy

Conjunctival Findings

  • Discharge: Purulent discharge is characteristic of bacterial conjunctivitis 1
  • Inflammation: Assess distribution (diffuse vs. sectoral)
  • Laterality: Unilateral or bilateral (often starts unilateral and becomes bilateral)
  • Chemosis: Evaluate degree of conjunctival edema
  • Hemorrhage: Note any subconjunctival hemorrhage

Eyelid Margins

  • Inflammation and edema
  • Meibomian gland dysfunction
  • Discharge characteristics (purulent in bacterial cases)
  • Ulceration, nodules, vesicles

Eyelashes

  • Crusting
  • Presence of scurf or mites (Demodex)
  • Trichiasis

Cornea

  • Critical: Rule out corneal involvement (epithelial defects, infiltrates) 2
  • Apply fluorescein staining to detect epithelial defects
  • Assess for stromal infiltrates which would suggest keratitis rather than simple conjunctivitis

Anterior Chamber

  • Check for inflammatory reaction (cells and flare)
  • Presence of hypopyon would indicate more severe infection

Distinguishing Features of Bacterial Conjunctivitis

  • Discharge: Mucopurulent or purulent discharge (thicker than viral conjunctivitis)
  • Conjunctival Reaction: Papillary rather than follicular reaction
  • Eyelids: Often stuck together upon waking due to discharge
  • Time Course: Typically acute onset

Red Flags Requiring Immediate Referral

  • Moderate to severe pain (bacterial conjunctivitis typically causes irritation but not severe pain) 2
  • Visual loss
  • Corneal involvement (infiltrates or epithelial defects)
  • Severe purulent discharge (may indicate hyperacute conjunctivitis from Neisseria)
  • Lack of response to therapy within 48-72 hours
  • Immunocompromised patient

Diagnostic Testing Considerations

  • Cultures are not routinely needed for uncomplicated bacterial conjunctivitis 1
  • Consider cultures for:
    • Recurrent, severe, or chronic purulent conjunctivitis
    • Cases not responding to initial treatment
    • Suspected hyperacute conjunctivitis (Neisseria)
    • All cases of neonatal conjunctivitis 1

Documentation Pearls

  • Document laterality and onset pattern
  • Note specific discharge characteristics (color, consistency, amount)
  • Record presence or absence of corneal involvement
  • Document response to lid eversion (to assess for foreign body or papillary reaction)
  • Specify any associated systemic symptoms

By following this systematic approach to the physical examination of bacterial conjunctivitis, clinicians can accurately diagnose the condition, distinguish it from other causes of red eye, and identify cases requiring specialty referral or additional testing.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Ocular Infections and Emergency Referral

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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