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Bacterial conjunctivitis is common and caused by Staphylococcus
, Haemophilus influenzae
, Streptococcus pneumoniae
is acquired from infection in the mother's
genital tract and caused by Neisseria gonorrhoeae
, Escherichia coli
, S. aureus
and H. influenzae
. In hospital
if ocular equipment or drops are not adequately sterilized or
restricted to a single use, infection with Pseudomonas aeruginosa
may occur. Infection is also associated with contaminated personal
contact-lens cleaning equipment. Pseudomonas
infection may be
rapidly progressive, resulting in ocular perforation and loss of
vision. Bacterial conjunctivitis presents with hyperaemic, red conjunctivae
and a profuse, mucopurulent discharge. Conjunctival
swabs and corneal scrapings are submitted for laboratory examination.
The diagnosis is confirmed by bacterial culture or nucleic
acid amplification test (NAAT) including for C. trachomatis.
Treatment is with local antibiotics, which include fusidic acid,
tetracycline chloramphenicol or fluoroquinolones.
Half of the adenovirus serotypes have been associated with ocular
infection, but types 7, 3, 11, 19 and 37are most commonly
Varicella zoster virus
- Purulent conjunctivitis occurs, with enlargement of the ipsilateral
periauricular lymph node.
- Corneal involvement leads to punctate keratitis and subepithelial
inflammatory infiltration, anterior uveitis and conjunctival
- Treatment is symptomatic, with antibacterial agents being used
if there is evidence of secondary bacterial infection. Topical steroids
should be avoided. New drugs are in early phase trials.
The ophthalmic dermatome of the fifth cranial nerve is involved
in approximately 10% of recurrent varicella zoster virus (VZV)
infections (shingles). Ocular involvement, manifests in anterior
uveitis, keratitis, ocular perforation or retinal involvement.
Chronic disease occurs in about one-quarter of patients. The
condition is very painful and pain may continue after healing
of the rash (Postherpetic neuralgia
). Antiviral agents (e.g.
aciclovir) should be used early in the infection and may prevent
complications. Severe inflammation may benefit from topical steroids.
A live attenuated vaccine is available to prevent primary
Ocular infection with herpes simplex is the most common infectious
cause of blindness in developed countries.
Ocular manifestations of AIDS
- Ulcerative blepharitis, corneal involvement, follicular conjunctivitis
and regional lymphadenopathy occur.
- Relapses occur approximately every 4 years.
- Initially, a dendritic ulcer is present, but the later clinical picture
is dominated by inflammation in deeper tissues, keratitis, corneal
oedema and opacity.
- Primary infection and early relapses are treated with topical
aciclovir. Steroids worsen the keratitis.
- Progressive scarring that follows repeated attacks leads to
corneal opacity and is a common indication for corneal grafting.
'Cotton wool spots' are a common retinal manifestation of
untreated HIV infection due to infarction of the retinal nerve
fibre layer. Cytomegalovirus (CMV) and fungal infection may
develop in patients with very low CD4 counts. CMV causes a
slowly progressive retinitis characterized by necrosis and may
lead to blindness. The syndrome is difficult to differentiate from
ocular toxoplasmosis or syphilitic retinitis. Initial treatment with
parenteral ganciclovir followed by weekly maintenance therapy to
prevent relapse is used. Immune-recovery uveitis can occur after
the introduction of highly active antiretroviral therapy (HAART).
- Trachoma is a chronic keratoconjunctivitis caused by infection
with C. trachomatis, which is now largely confined to the tropics,
where poor social conditions make transmission easier and poverty
reduces access to health care.
- Symptoms develop 3-10 days after infection, with lacrimation,
mucopurulent discharge, conjunctival infection and follicular
hypertrophy. Treatment is with oral macrolides, such as
- An international campaign plan to eradicate trachoma by 2020
is under way using the SAFE strategy (Surgery for in-turned lids,
Antibiotics, Face washing and Environmental improvement).
- Endophthalmitis can develop after an ocular operation, following
trauma, due to the presence of a foreign body or as a complication
of systemic infection.
- Early postoperative infections are commonly with S. aureus,
Staphylococcus epidermidis, streptococci or Gram-negative
- Late postoperative infections are with streptococci or H.
- Post-traumatic infections are caused by S. epidermidis, Bacillus
- Endogenous infections secondary to bacteraemia or fungaemia
are most often with Candida, streptococci and enteric Gramnegative
- Rarely, endophthalmitis is caused by the nematode Toxocara
canis (see Zoonoses
- The diagnosis is made by vitreous aspiration or vitrectomy
- Bacterial endophthalmitis is managed by systemic antibiotics or
intravitreal injection, depending on the spectrum and pharmacokinetics
of the agents.