Changes

October 2022 — minor update. Links to some references were updated.

Update

Goals

To support primary healthcare professionals to:

• Make a diagnosis of infective conjunctivitis in primary care.
• Advise on self-care and infection control.
• Manage the symptoms of infective conjunctivitis.
• Refer to ophthalmology or seek advice as appropriate.

Outcome measures

No outcome measures were found during the review of this topic.

Audit criteria

No audit criteria were found during the review of this topic.

QOF indicators

No QOF indicators were found during the review of this topic.

QIPP - Options for local implementation

No QIPP indicators were found during the review of this topic.

NICE Quality standards

No NICE quality standards were found during the review of this topic.

What is it?

• Conjunctivitis is an inflammation of the conjunctiva due to allergic or immunological reactions, infection (viral, bacterial or parasitic), mechanical irritation, neoplasia, or contact with toxic substances [Castillo, 2015; AAO, 2019; BMJ Best Practice, 2021].
  • The conjunctiva is a thin, transparent mucous membrane lining the anterior part of the sclera (bulbar conjunctiva) and the under-surface of the eyelids (palpebral conjunctiva) [Azari, 2013; Alfonso, 2015].
  • Inflammation or infection of the conjunctiva causes dilation of conjunctival vessels leading to hyperaemia and oedema of the conjunctiva which may be associated with discharge [Azari, 2013].
• Infective conjunctivitis can be acute (persisting for less than 4 weeks), chronic (persisting for more than 4 weeks), or recurrent [Alfonso, 2015].
  • Hyperacute conjunctivitis is a rapidly developing severe conjunctivitis typically caused by infection with Neisseria gonorrhoeae.
  • Ophthalmia neonatorum (ON) is conjunctivitis occurring within the first four weeks of life — it can be infectious or non-infectious.
    • Infectious ON can be caused by Neisseria gonorrhoeae or Chlamydia trachomatis and is associated with serious complications if not treated promptly and appropriately [Matejcek, 2013; Canadian Paediatric Society, 2021; College of Optometrists, 2021a].

How common is it?

Infective conjunctivitis is common — acute infective conjunctivitis accounts for approximately 1% of all GP consultations in the UK.

• Viral conjunctivitis
  • Viral conjunctivitis is the most common infectious conjunctivitis — up to 80% of all cases of acute conjunctivitis may be caused by viral infection.
  • Herpes simplex virus is estimated to cause 1.3–4.8% of cases of acute conjunctivitis.
• Bacterial conjunctivitis
  • Bacterial conjunctivitis is the second most common cause of infectious conjunctivitis.
  • Between 50–75% of cases of infective conjunctivitis in children are thought to be due to bacterial infection.
  • A US study using data from the 2005 National Ambulatory Medical Care Survey (NAMCS) estimated the incidence of bacterial conjunctivitis in the United States to be 135 per 10,000 [Smith, 2009].
• Ophthalmia neonatorum (ON)
  • In the UK, the incidence of ON due to [College of Optometrists, 2021a]:
    • Chlamydia trachomatis is 6.9/100,000 live births.
    • Neisseria gonorrhoeae is 3.7/100,000 live births.
  • An analysis of hospital episode statistics from 2000 to 2011 in England found the incidence rate of hospitalised cases of ON to be 257 per 100,000 live births in 2011 (95% CI, 245–269). Marked cyclical fluctuations in incidence were noted over time [Dharmasena, 2015].
  • Viral ON (for example due to Herpes simplex, adenovirus, and enterovirus) is less common.

[Jefferis, 2011; Matejcek, 2013; RCGP, 2013; Azari, 2020; BMJ Best Practice, 2021; Canadian Paediatric Society, 2021]

What causes infectious conjunctivitis?

• Viral conjunctivitis
  • The most common cause of viral conjunctivitis is adenovirus (65–90% of cases).
  • Other viral causes include Herpes simplex, Varicella zoster, Molluscum contagiosum, Epstein-Barr, coxsackie and enteroviruses.
• Bacterial conjunctivitis
  • The most common bacterial causes of conjunctivitis are Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae.
  • Other bacterial causes include Moraxella catarrhalis, Chlamydia trachomatis, and Neisseria gonorrhoea.
  • In children, bacterial conjunctivitis is most often caused by Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis.
• Ophthalmia neonatorum (ON)
  • ON can be caused by many microorganisms including Chlamydia trachomatis (serotypes D–K), Neisseria gonorrhoea, haemophilus species, streptococcus species, staphlococcal species, Escherichia coli, pseudomonas, adenovirus, and Herpes simplex.
  • Non-sexually transmitted bacteria account for 30–50% of cases of ON.

[Matejcek, 2013; RCGP, 2013; Alfonso, 2015; Drew, 2015; AAO, 2019; Azari, 2020; College of Optometrists, 2020; BMJ Best Practice, 2021; College of Optometrists, 2021b; College of Optometrists 2021; College of Optometrists, 2021a] 

What complications are associated with infective conjunctivitis?

Complications due to infective conjunctivitis are uncommon but visual loss and structural damage can occur in some cases:

• Viral conjunctivitis
  • Adenoviruses can cause epidemic keratoconjunctivitis ­­— 30–50% of people with epidemic keratoconjunctivitis develop subepithelial infiltrates, which can cause persistent visual loss and light sensitivity.
• Bacterial conjunctivitis
  • Occasionally bacterial conjunctivitis can cause keratitis in people who wear contact lenses or who are immunocompromised.
  • Conjunctivitis caused by Neisseria gonorrhoeae is associated with a high risk of corneal perforation.
• Ophthalmia neonatorum (ON)
  • Complications of chlamydial ON include superficial corneal vascularization, conjunctival scarring and pneumonia.
  • Complications of gonorrheal ON include corneal scarring, ulceration, panophthalmitis, perforation of the globe and permanent visual impairment.
  • ON caused by pseudomonas is rare but can lead to serious complications including corneal perforation, endophthalmitis, blindness, and mortality.
• Trachoma
  • Trachoma is a chronic keratoconjunctivitis found mostly in sub-Saharan Africa. It is due to recurrent infection with Chlamydia trachomatis in childhood and can cause scarring of the eyelid, conjunctiva and cornea.
  • It is the most common cause of infectious blindness worldwide.

[Azari, 2013; Matejcek, 2013; Alfonso, 2015; Nwokolo, 2015; Azari, 2020; BMJ Best Practice, 2021; Canadian Paediatric Society, 2021; College of Optometrists, 2021a]

What is the prognosis?

Acute conjunctivitis is usually self-limiting and rarely causes loss of vision.

• Viral conjunctivitis
  • Most cases resolve in about 7 days.
  • The incubation and communicable intervals of conjunctivitis associated with adenoviruses are 5–12 days and 10–14 days respectively.
• Bacterial conjunctivitis
  • Most cases resolve within 5 to 10 days.
  • Contact lens wearers and immunocompromised people have the greatest risk of complications.
• Ophthalmia neonatorum (ON)
  • Most cases are mild, however, untreated infection (such as gonococcus, chlamydia, pseudomonas or herpes) can lead to serious complications including sight loss and mortality.

[Azari, 2013; Usher, 2014; Alfonso, 2015; Drew, 2015; BMJ Best Practice, 2021; College of Optometrists, 2021a]

What are the clinical features of infective conjunctivitis?

The clinical features of conjunctivitis include:

• Acute onset conjunctival erythema.
• Discomfort which may be described as ‘grittiness’, ‘foreign body’ or ‘burning’ sensation.
• Watering and discharge which may cause transient blurring of vision.

It is difficult to differentiate viral and bacterial conjunctivitis clinically.

• Bacterial conjunctivitis may be associated with:
  • Purulent or mucopurulent discharge with crusting of the lids which may be stuck together on waking.
    • If discharge is mucopurulent and copious, infection with Neisseria gonorrhoeae should be considered.
  • Mild or no pruritus.
  • Pre-auricular lymphadenopathy — often seen with hyperacute bacterial conjunctivitis (such as Neisseria gonorrhoea).
• Viral conjunctivitis may be associated with:
  • Mild to moderate erythema of the palpebral or bulbar conjunctiva, follicles on eyelid eversion and lid oedema.
  • Petechial (pin-point) subconjunctival haemorrhages.
  • Pseudomembranes — may form on tarsal conjunctival surfaces in severe cases.
    • Epidemic keratoconjunctivitis (due to adenovirus) can lead to pseudomembrane formation along with severe pain, subconjunctival haemorrhage, visual changes, and photophobia.
  • Less discharge (usually watery) than bacterial conjunctivitis.
  • Mild to moderate pruritus.
  • Upper respiratory tract infection and pre-auricular lymphadenopathy.
    • Pharyngoconjunctival fever (due to adenovirus) can lead to fever, pharyngitis, periauricular lymphadenopathy, and bilateral conjunctivitis occasionally with corneal involvement.
• Herpes virus may be indistinguishable from other viral infections:
  • Herpes simplex typically presents as unilateral red eye with vesicular lesions visible on the eyelid and watery discharge.
  • Ocular involvement in Herpes zoster infection should be assumed if lesions are present at the tip of the nose (Hutchinson's sign).
  • For further information, see the CKS topics on Herpes simplex - ocular and Shingles.
• Contact lens associated conjunctivitis
  • Inflammation may be seen in the superior conjunctiva especially under the upper lid — topical fluorescein may identify corneal staining (epithelial defect).
• Sexually transmitted infection (STI) — conjunctivitis due to STI is often more severe and associated with prolonged mucopurulent discharge.
  • Chlamydia trachomatis
    • Often presents with a chronic (longer than 2 weeks) low-grade irritation and mucous discharge in a sexually active person. Pre-auricular lymphadenopathy may be present.
    • Most cases are unilateral but may be bilateral.
  • Neisseria gonorrhoea (GC)
    • Symptoms usually develop rapidly (over 12–24 hours) with copious mucopurulent discharge, eyelid swelling, and tender preauricular lymphadenopathy.
    • GC conjunctivitis has a high risk of complications including uveitis, severe keratitis, and corneal perforation.
• Ophthalmia neonatorum (ON)
  • Chlamydial ON — typically presents with a watery or mucopurulent discharge about 5–14 days after birth.
  • Gonococcal ON — typically presents within the first 5 days of life but can also present up to 3 weeks after delivery. It is characterised by copious purulent discharge and eyelid swelling which may be severe.
  • Viral ON — most commonly due to adenovirus or Herpes simplex virus. May present with petechial or occasionally large subconjunctival haemorrhages and lymphadenopathy.

How should I assess a person with suspected infective conjunctivitis?

Assess all people presenting with a unilateral red eye for features indicating a serious and potentially sight-threatening cause (such as acute glaucoma, corneal ulcer, anterior uveitis, scleritis, or trauma) — for further information, see the CKS topic on Red eye.

Take a history asking about:

• Onset and duration of symptoms.
• Clinical features:
  • Distribution of symptoms — unilateral or bilateral.
  • Amount and character (watery, purulent, or mucopurulent) of discharge and when it is worst (for example on waking from sleep).
  • Itching.
  • Changes in vision such as blurring.
  • Eyelid changes such as swelling, flaking and vesicles.
• Recent exposure to an infected person.
• Red flags which indicate the need for urgent ophthalmological assessment such as:
  • Reduced visual acuity.
  • Marked eye pain, headache or photophobia — always consider serious systemic conditions such as meningitis in a person presenting with photophobia.
  • Red sticky eye in a neonate (within 30 days of birth).
  • History of trauma (mechanical, chemical or ultraviolet) or possible foreign body.
  • Copious rapidly progressive discharge — may indicate gonococcal infection.
  • Infection with a herpes virus.
  • Soft contact lens use with corneal symptoms (such as photophobia and watering).
• Associated symptoms such as:
  • Upper respiratory tract infection.
  • Enlarged tender lymph nodes.
• Past medical history including:
  • History of atopy, allergy and similar episodes.
  • Immunocompromise for example HIV, chemotherapy or immunosuppressant treatment.
  • Associated systemic conditions such as rheumatoid arthritis, systemic lupus erythematous, and reactive arthritis.
  • Ophthalmic surgery.
  • Drug history including prescribed and over-the-counter topical and systemic drugs such as mydriatics, anticholinergics and anticoagulants.
  • Social history including smoking, occupation, hobbies, sexual activity, and travel.

Examine the person to assess the:

• Conjunctiva — look for injection, chemosis (swelling), follicles, papillae and membranes. Pull on lower eyelid and evert upper lid to examine the palpebral conjunctiva.
• Follicles (small yellowish elevations of lymphocytes) can be associated with adenovirus and chlamydia.
• Papillae (small conjunctival elevations with central vessels) can be associated with allergic conjunctivitis and contact lens intolerance.
• Conjunctival membranes (yellow/white layer of fibrin adherent to underlying conjunctival tissue) can form in severe viral or bacterial infections and cause complications such as conjunctival scarring and severe dry eye.
• Cornea – look for ulceration and opacities.
• If available, consider evaluation of the cornea with a Wood lamp and fluorescein staining to identify pathology such as corneal dendrites in HSV keratitis and corneal ulcers.
• Sclera — look for localized or widespread oedema and erythema which indicates a serious cause such as scleritis.
• Pupil — assess shape, size and pupillary reaction (with a pen torch) and look for asymmetric or unreactive pupils.
• Visual acuity (using a Snellen chart) and visual fields — compare with previous measurements of visual acuity, if possible. 
• Eyelids – look for discharge, swelling, inflammation, malposition, nodules, loss of lashes (may indicate sebaceous gland carcinoma), vesicles (herpes) or blepharitis.
  • Herpes simplex (HSV) — may present as unilateral red eye with vesicular lesions on the eyelid.
  • Herpes zoster — assume ocular involvement if lesions are present on the tip of the nose (Hutchinson's sign).
• Periorbital area — look for swelling and erythema which may indicate orbital or periorbital cellulitis. Periorbital cellulitis can develop from conjunctivitis in young children.
• Lymph nodes — look for regional lymphadenopathy.

Arrange appropriate investigations:

• Do not routinely take swabs – swabs may be appropriate, if the person does not need to be referred, but fails to respond to initial treatment.
• Swabs need to be good quality and well labelled with appropriate clinical detail — ensure that the correct medium is used and care is taken to avoid contamination of the culture with skin flora from eyelids and lashes.
• Swabs for severe purulent discharge (which may indicate gonococcal infection) or conjunctivitis in neonates, should be carried out urgently in secondary care.

What else might it be?

There are many causes of red eye, some of which are serious or sight threatening and require same day assessment by ophthalmology — for further information, see the CKS topic on Red eye. The differential diagnosis for infective conjunctivitis includes:

• Serious conditions such as:
  • Acute glaucoma.
  • Scleritis.
  • Episcleritis.
  • Keratitis.
  • Uveitis.
  • Iritis.
  • Corneal ulcer, abrasion or foreign body.
• Non-infectious conjunctivitis:
  • Atopic or allergic conjunctivitis — may be recurrent due to seasonal or environmental factors.
  • Toxic conjunctivitis — for example drop allergy and preservative-related red eye.
    • Overuse of cosmetic drops to whiten the conjunctiva can lead to permanently dilated vessels and red eyes.
  • Irritative or mechanical conjunctivitis — for example due to contact-lens use, floppy eyelid syndrome, Pediculosis palpebrarum (Phthirus pubis) or medication.
  • Immune-mediated inflammation (such as Stevens-Johnson syndrome) or neoplasia (such as sebaceous carcinoma or melanoma).
• Other conditions affecting the eye such as:
  • Nasolacrimal duct obstruction — discharge without red eye in neonates can be due to congenital obstruction of the nasolacrimal duct(s).
  • Subconjunctival haematoma.
  • Dry eye.
  • Blepharitis.
  • Blepharokeratoconjunctivitis — chronic inflammation of the surface of the eye and eyelids which can lead to corneal scarring, vascularisation and opacity.
  • Thyroid eye disease.

Scenario: Who should I refer to ophthalmology?

From birth onwards.

Scenario: Management in primary care

From age 1 month onwards.

Topical chloramphenicol

Topical fusidic acid

Search strategy

Scope of search

A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on primary care management of conjunctivitis - infective.

Search dates

May 2017 - April 2022

Key search terms

Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline.

• exp Conjunctivitis/, exp Conjunctivitis, Bacterial/, exp Conjunctivitis, Viral/, conjunctivitis.tw., (infect$ ADJ conjunctivitis).tw., (bacterial ADJ conjunctivitis).tw., (neonatal ADJ conjunctivitis).tw.

Sources of guidelines

• National Institute for Health and Care Excellence (NICE)
• Scottish Intercollegiate Guidelines Network (SIGN)
• Royal College of Physicians
• Royal College of General Practitioners
• Royal College of Nursing
• NICE Evidence
• World Health Organization
• Guidelines International Network
• TRIP database
• Agency for Healthcare Research and Quality
• Institute for Clinical Systems Improvement
• National Health and Medical Research Council (Australia)
• Royal Australian College of General Practitioners
• British Columbia Medical Association
• Canadian Medical Association
• Alberta Medical Association
• Michigan Quality Improvement Consortium
• Singapore Ministry of Health
• National Resource for Infection Control
• RefHELP NHS Lothian Referral Guidelines
• Medline (with guideline filter)
• Driver and Vehicle Licensing Agency
• NHS Health at Work (occupational health practice)

Sources of systematic reviews and meta-analyses

• The Cochrane Library:
  • Systematic reviews
  • Protocols
  • Database of Abstracts of Reviews of Effects
• Medline (with systematic review filter)
• EMBASE (with systematic review filter)

Sources of health technology assessments and economic appraisals

• NIHR Health Technology Assessment programme
• The Cochrane Library:
  • NHS Economic Evaluations
  • Health Technology Assessments
• Canadian Agency for Drugs and Technologies in Health
• International Network of Agencies for Health Technology Assessment

Sources of randomized controlled trials

• The Cochrane Library:
  • Central Register of Controlled Trials
• Medline (with randomized controlled trial filter)
• EMBASE (with randomized controlled trial filter)

Sources of evidence based reviews and evidence summaries

• Bandolier
• Drug and Therapeutics Bulletin
• TRIP database
• Central Services Agency COMPASS Therapeutic Notes

Sources of national policy

• Department of Health
• Health Management Information Consortium (HMIC)

Patient experiences

• Healthtalk
• BMJ - Patient Journeys

Sources of medicines information

The following sources are used by CKS pharmacists and are not necessarily searched by CKS information specialists for all topics. Some of these resources are not freely available and require subscriptions to access content.

• British National Formulary (BNF)
• electronic Medicines Compendium (eMC)
• European Medicines Agency (EMEA)
• LactMed
• Medicines and Healthcare products Regulatory Agency (MHRA)
• REPROTOX
• Scottish Medicines Consortium
• Stockley's Drug Interactions
• TERIS
• TOXBASE
• Micromedex
• UK Medicines Information

Stakeholder engagement

Our policy

The external review process is an essential part of CKS topic development. Consultation with a wide range of stakeholders provides quality assurance of the topic in terms of:

• Clinical accuracy.
• Consistency with other providers of clinical knowledge for primary care.
• Accuracy of implementation of national guidance (in particular NICE guidelines).
• Usability.

Principles of the consultation process

• The process is inclusive and any individual may participate.
• To participate, an individual must declare whether they have any competing interests or not. If they do not declare whether or not they have competing interests, their comments will not be considered.
• Comments received after the deadline will be considered, but they may not be acted upon before the clinical topic is issued onto the website.
• Comments are accepted in any format that is convenient to the reviewer, although an electronic format is encouraged.
• External reviewers are not paid for commenting on the draft topics.
• Discussion with an individual or an organization about the CKS response to their comments is only undertaken in exceptional circumstances (at the discretion of the Clinical Editor or Editorial Steering Group).
• All reviewers are thanked and offered a letter acknowledging their contribution for the purposes of appraisal/revalidation.
• All reviewers are invited to be acknowledged on the website. All reviewers are given the opportunity to feedback about the external review process, enabling improvements to be made where appropriate.

Stakeholders

• Key stakeholders identified by the CKS team are invited to comment on draft CKS topics. Individuals and organizations can also register an interest to feedback on a specific topic, or topics in a particular clinical area, through the Getting involved section of the Clarity Informatics website.
• Stakeholders identified from the following groups are invited to review draft topics:
  • Experts in the topic area.
  • Professional organizations and societies (for example, Royal Colleges).
  • Patient organizations, Clarity has established close links with groups such as Age UK and the Alzheimer’s Society specifically for their input into new topic development, review of current topic content and advice on relevant areas of expert knowledge.
  • Guideline development groups where the topic is an implementation of a guideline.
  • The British National Formulary team.
  • The editorial team that develop MeReC Publications.
• Reviewers are provided with clear instructions about what to review, what comments are particularly helpful, how to submit comments, and declaring interests.

Patient engagement

Clarity Informatics has enlisted the support and involvement of patients and lay persons at all stages in the process of creating the content which include:

• Topic selection
• Scoping of topic
• Selection of clinical scenarios
• First draft internal review
• Second draft internal review
• External review
• Final draft and pre-publication

Our lay and patient involvement includes membership on the editorial steering group, contacting expert patient groups, organizations and individuals.

Evidence exclusion criteria

Our policy

Scoping a literature search, and reviewing the evidence for CKS is a methodical and systematic process that is carried out by the lead clinical author for each topic. Relevant evidence is gathered in order that the clinical author can make fully informed decisions and recommendations. It is important to note that some evidence may be excluded for a variety of reasons. These reasons may be applied across all CKS topics or may be specific to a given topic.

Studies identified during literature searches are reviewed to identify the most appropriate information to author a CKS topic, ensuring any recommendations are based on the best evidence. We use the principles of the GRADE and PICOT approaches to assess the quality of published research. We use the principles of AGREE II to assess the quality of published guidelines.

Standard exclusions for scoping literature:

• Animal studies
• Original research is not written in English

Possible exclusions for reviewed literature:

• Sample size too small or study underpowered
• Bias evident or promotional literature
• Population not relevant
• Intervention/treatment not relevant
• Outcomes not relevant
• Outcomes have no clear evidence of clinical effectiveness
• Setting not relevant
• Not relevant to UK
• Incorrect study type
• Review article
• Duplicate reference

Organizational, behavioural and financial barriers

Our policy

The CKS literature searches take into consideration the following concepts, which are discussed at the initial scoping of the topic.

• Feasibility
  • Studies are selected depending on whether the intervention under investigation is available in the NHS and can be practically and safely undertaken in primary care.
• Organizational and Financial Impact Analysis
• Studies are selected and evaluated on whether the intervention under investigations may have an impact on local clinical service provision or national impact on cost for the NHS. The principles of clinical budget impact analysis are adhered to, evaluated and recorded by the author. The following factors are considered when making this assessment and analysis.
  • Eligible population
  • Current interventions
  • Likely uptake of new intervention or recommendation
  • Cost of the current or new intervention mix
  • Impact on other costs
  • Condition-related costs
  • In-direct costs and service impacts
  • Time dependencies
• Cost-effectiveness or cost-benefit analysis studies are identified where available. 

We also evaluate and include evidence from NICE accredited sources which provide economic evaluations of recommendations, such as NICE guidelines. When a recommended action may not be possible because of resource constraints, this is explicitly indicated to healthcare professionals by the wording of the CKS recommendation.

Declarations of interest

Our policy

Clarity Informatics requests that all those involved in the writing and reviewing of topics, and those involved in the external review process to declare any competing interests. Signed copies are securely held by Clarity Informatics and are available on request with the permission of the individual. A copy of the declaration of interest form which participants are asked to complete annually is also available on request. A brief outline of the declarations of interest policy is described here and full details of the policy is available on the Clarity Informatics website. Declarations of interests of the authors are not routinely published, however competing interests of all those involved in the topic update or development are listed below. Competing interests include:

• Personal financial interests
• Personal family interest
• Personal non-financial interest
• Non-personal financial gain or benefit

Although particular attention is given to interests that could result in financial gains or losses for the individual, competing interests may also arise from academic competition or for political, personal, religious, and reputational reasons. An individual is not obliged to seek out knowledge of work done for, or on behalf of, the healthcare industry within the departments for which they are responsible if they would not normally expect to be informed.

Who should declare competing interests?

Any individual (or organization) involved in developing, reviewing, or commenting on clinical content, particularly the recommendations should declare competing interests. This includes the authoring team members, expert advisers, external reviewers of draft topics, individuals providing feedback on published topics, and Editorial Steering Group members. Declarations of interest are completed annually for authoring team and editorial steering group members, and are completed at the start of the topic update and development process for external stakeholders.

Competing interests declared for this topic:

None.