Eye infections Flashcards
(18 cards)
What is the most common cause of anterior blepharitis?
Staphylococci.
Name three bacteria that commonly cause bacterial conjunctivitis.
Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae.
What is the first-line treatment for anterior blepharitis?
Eyelid hygiene.
What additional treatment may be used in anterior blepharitis if hygiene is insufficient?
Antibacterial ointment (e.g. chloramphenicol).
How is posterior blepharitis commonly treated?
Systemic antibiotics such as tetracyclines (≥12 years old).
When should antibacterial eye drops/ointments be used in bacterial conjunctivitis?
If the infection is severe or rapid resolution is needed.
Why does keratitis (inflammation of the cornea) require specialist care?
It may need hospital admission and intensive treatment.
How is trachoma treated?
Trachoma is an infectious disease caused by bacterium Chlamydia trachomatis. The infection causes a roughening of the inner surface of the eyelids. This roughening can lead to pain in the eyes, breakdown of the outer surface or cornea of the eyes, and eventual blindness.
Oral azithromycin (WHO-recommended; unlicensed in UK).
What is the mechanism of action of chloramphenicol?
It inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit.
What are the main licensed indications for topical chloramphenicol?
Bacterial conjunctivitis and superficial eye infections.
What is the usual dosing for chloramphenicol eye drops in bacterial conjunctivitis?
1 drop every 2 hours for the first 48 hours, then reduce frequency; continue for 5 days.
What is the usual dosing for chloramphenicol eye ointment?
Apply 3–4 times daily for 5 days.
What age restriction applies to chloramphenicol eye drops and ointment in the UK?
Available OTC for children aged 2 years and over.
What are common side effects of topical chloramphenicol?
Transient stinging or burning, local irritation, hypersensitivity reactions.
Why is systemic use of chloramphenicol limited?
Risk of serious toxicity, including bone marrow suppression and aplastic anaemia.
What is the advice regarding contact lenses and chloramphenicol use?
Do not wear contact lenses during treatment or for at least 24 hours after.
What caution is advised for patients with a history of blood dyscrasias?
Avoid use or use with extreme caution due to risk of marrow suppression.
How should chloramphenicol eye drops be stored?
Store in the refrigerator (2–8°C); discard 5 days after opening (or 28 days if advised).
