Conjuctival diseases

Introduction

• The conjunctiva is a thin vascularised mucous membrane consisting of a non keratinising, stratified, columno-squamous epithelium and a substantia propria.

• It leaves the posterior surface of the eyelids from which it is reflected forwards at the fornices, to cover the anterior sclera.

Subdivisions• 1. palpebral.

it is firmly adherent to the tarsal plate.

• 2. fornicial.

loose, redundant and swells easily.

• 3. bulbar.

covers ant sclera.

loosely attached to underlying Tenonexcept at limbus.

Histology

• 1. conjunctival epithelium2-5 cells layer

- epithelial basal wing and superficial polyhedral cells

- others : • - melanocytes (in the basal

layer)• - Langerhans antigen

presenting cells also (in the basal layer)

• - goblet cells more numerous in the fornices and plica (infro nasaly)

• 2. the stroma ( substantia propria)

- richly vascularized connective tissue.

Note:-

Adenoid superfacial layer doesn’t develop until age of 3 months.

Conjunctivitis

• Conjunctivitis is an inflammatory process involving the surface of the eye and characterized by vascular dilation, cellular infiltration, and exudation.

• Two forms of the disorder are distinguished:

• 1. Acute conjunctivitis. Onset is abrupt and initially unilateral with inflammation of the second eye within one week. Duration is less than four weeks.

• 2. Chronic conjunctivitis. Duration is longer than three to four weeks.

Conjunctivitis

• The most common ophthalmic symptom is one of "red sticky eyes" secondary to conjunctivitis.

• Types of conjunctivitis-Bacterial-Chlamydial-Viral-Allergic/Hypersensitivity-Toxic-Other

Others:• Blepharo-conjunctivitis.• Rosacea kerato-

conjunctivitis• Dry eye syndromes.• Fungal conjunctivitis.• Parasitic conjunctivitis.• Ligneous conjunctivitis.• Granulomatous

conjunctivitis.• Systemic disease.

Conjunctivitis may be a feature of a number of systemic disorders including rheumatoid arthritis, Wegener's granulomatosis, Stevens-Johnson syndrome, Lyell's syndrome (toxic epidermal necrolysis), scleroderma and linear IgA disease.

Clinical evaluation

• Differential diagnosis determined from:

a. symptoms (eg. pain, Itching).

b. discharge.

c. conjunctival reaction.

d. membranes

e. lymphadenopathy.

Discharge• It is exudate with epith debris, mucus and tears.

1. Watery (serous exudate+tears):

acute viral, allergic.

2. Mucoid :

vernal conj & keratoconj sicca.

3. purulent: severe acute bacterial.

4. mucopurulent:

mild bacterial, chlamydial.

Conjunctival reaction• 1. Injection: more in fornices.

• 2. subconjunctival hemorrhage

usually viral (mainly

picorna) highly infectious but self-

limiting.

also strep. Pnemonia & H. aegypticus do.

• 3. Oedema (chemosis)In severely inflamed conj due to protien rich fluid

• 4. Scarring

trachoma, ocular cicatricial pemphygoid, atopic conjunctivitis & prolonged use of topical medications.

6. Papillary reaction• Non specific.

• Hyperplastic conjunctival epithelium with central vessels & diffuse infiltrate of chronic inflamatorycells.

• Can develop only in palpebral conj & bulbar at limbus.

• Mostly seen in upper palpebral conj as fine mosaic-like elevated polygonal hyperemic areas separated by palor channels.

• Causes: chronic blepharitis, allergic & bactconjunctivitis, contact lenses and superior limbic keratoconjunctivitis.

• Note: the appearance of normal sup edge of tarsal plate( inf when inverted) may mimic papillae & follicles so should not be used as a clinical sign.

Membranes

• 1. pseudo membranes:

coagulated exudate

adherent w inflamed conj, easily peeled of leaving intact epithelium.

Causes: adenoviral, gonococcal, ligneous conj & Steven Johnson

syndrome.

• 2. true membrane:

infiltrate superfeciallayer of epithconj.

if removed bleeding occurs.

causes: strep pypgenes and diphtheria.

Lymphadenopathy

• Lymph drainage of the conj is to the preauricular and sub mandibular regions corresponding to the drainage of eye lids.

• Causes: viral, chlamydial, gonococcal and perinaud oculoglandular syndrome.

Lab investigations• Indications:

- sever purulent conjunctivitis.- follicular conjunctivitis.

to R/O chlamydial. - conjunctival inflammations

that are insufficient ti achieve diagnosis.- neonatal conjunctivitis.

• Cultures. These are usually made on blood (aerobic bacteria, fungi) and chocolate agar (neisseria, haemophilus), thioglycolate and meat broths(anaerobes) or on other special media when necessary. Sabouraud's agar and brain-heart broth may be used to grow fungi.

• Others: cytologic investigations, detection of viral or chlamydial antigens, impression cytology and PCR.

Simple bacterial conjunctivitis

• The commonest causative bacteria are Staphylococcus aureus (in children and adults), Streptococcus pneumonia and Haemophilus influenzas (especially in children) and others include Streptococcus viridans and pyogenes.

• It is a common self limiting condition mostly affecting children.

• Spread by direct contact with infected secretions.

-Usually the onset is relatively acute.

-The patient usually has discomfort and a purulent discharge in one eye that characteristically spreads to the other eye. The eye may be difficult to open in the morning because the discharge sticks the lashes together. There may be a history of contact with a person with similar symptoms.

- Discharge initially watery

mimiking viral.

History:

• —The vision should be normal after the discharge has been blinked clear

of the cornea. The discharge usually is mucopurulent and there is uniform engorgement of all the conjunctival blood vessels. When fluorescein drops are instilled in the eye there is no staining of the cornea.

• Injection maximal at fornices and less at limbus.

- Valvety, beefy red tarsal conjunctiva.

- Superfacial punctate epithelial erosions.

Examination

Management

• even without treatment, simple types resolves within 10-14 days .

• Topical antibiotic eye drops (for example, chloramphenicol) should be instilled every two hours for the first 24 hours to hasten recovery, decreasing to four times a day for one week. Chloramphenicol ointment applied at night may also increase comfort and reduce the stickiness of the eyelids in the morning. Patients should be advised about general hygiene measures; for example, not sharing face towels.

Gonococcal keratoconjunctivitis• Caused by gram –ve diplococcus

Neisseria gonorrhoeae.• It is capable of invading intact

corneal epith.

• Gonococcal conjunctivitis:-- acute profuse purulent discharge.

- edematous tender eye lids, hyperemia, chemosisand pseudo membranes.

- lymphadenopathy.

• Gonococcal keratitis:

- if conjunctivitis not treated well, keratitis occurs as follows:

1- marginal ulceration.

2 - coalescence to form a pereferal ring ulcer.

3 - central ulceration that may rapidly lead to perforation and endopthalmitis.

• Treatment:

1. admit, take cultures and remove discharge.

2. systemic

cefotaxime 1gm I.V b.d

( only 1 day if only conj involved).

3. topical gentamycin or bacitracin at very

frequent intervals.

Note: recognize and treat any associated chlamydialinfection.

Ophthalmia neonatorum

• is conjunctivitis occuring within the first three weeks of life.

• The most serious cause is infection with Neisseriagonorrhoeae,but in the UK it is caused more commonly by Chlamydia trachomatis (neonatal inclusion conjunctivitis - NIC) and by staphylococci or pneumococci. Herpes simplex type 2 virus is a relatively rare cause.

• Follicles and lymphadenopathy do not occur

• has an early onset from between 1 and 3 days post partum.

Management

• Specimens should be obtained from the child, the mother and her sexual partners).

• frequent irrigation.

• systemic and local antibiotics is appropriate for bacterial conditions and aciclovir is used in herpetic infection.

• Inclusion conjunctivitis is treated with systemic and topical erythromycin.

• In all cases, the mother and her sexual partner require appropriate treatment.

Adenoviral conjunctivitis

• varies from very mild to very severe.

• It is an occupational hazard of opthalmologists.

• It is highly contagious and transmitted via respiratory or ocular secretions & dissimination by towels and equipments as tonometer.

• Incubation period 4-10 days.

Adenoviral conjunctivitis.

• Adenoviral conjunctivitis can be classified into 3 types:

• -pharyngoconjunctival fever (PCF),type 3, 4or 7 & may be 5fever and general malaiseusually bilateral,

• -epidemic keratoconjunctivitis (EKC).adenovirus type 8 or 19absence of major systemic symptoms.usually unilateral

• -non-specific follicular conjunctivitis (NFC).mild adenoviral conjunctivitis, which is usually self-limiting

and requires no treatment.

Diagnosis is clinical, but can be aided by serology, or ELISA.

• Viral keratitis

• Stage 1:

- within 7-10 days

- punctate epith keratitis.

• Stage 2:

- focal white sub epithelial opacity, represents immune response.

• Stage 3:

- anterior stromal infiltrates fades over months to years.

• Clinical presentation

• acute watering, redness, discomfort & photophobia. Both eyes.

• usually lasts longer than bacterial conjunctivitis and may go on for many weeks; patients need to be informed of this.

• Photophobia and discomfort may be severe if the patient goes on to develop discrete corneal opacities.

• Examination

• bilateral diffuse conjunctival injection.

• clear discharge.

• Small white lymphoid aggregations may be present on the conjunctiva (follicles).

• Subconjunctivalhemorrhage.

• pre-auricular or submandibularlymphadenopathy

Management• Viral conjunctivitis is generally a self limiting condition,

So only symptomatic, they mostly resolves spontaneously within 2 weeks.

• but antibiotic eye drops (for example, chloramphenicol) provide symptomatic relief and help prevent secondary bacterial infection. Viral conjunctivitis is extremely contagious, and strict hygiene measures are important for both the patient and the doctor; for example, washing of hands and sterilizing of instruments. The period of infection is often longer than with bacterial pathogens and patients should be warned that symptoms may be present for several weeks. In some patients the infection may have a chronic, protracted course and steroid eye drops may be indicated if the corneal lesions and symptoms are persistent.