Red eye: Infections Flashcards
Blepharitis
Glands around eye gets clogged and secretions build up -> inflammation of lid margin
- Caused by Staph aureus or Meibomian gland abnormality
Symptoms of blepharitis
Lid crusting
Redness
Telangiectasia
Misdirected lashes
FB sensation
Itch
A/w chalazion and stye
Treatment of blepharitis
- Lid hygiene, diluted baby shampoo
- Topical Abx (Fucithalmic or tetracycline eye ointment)
- Lubricants
- Oral doxycycline if severe
Chalazion
Nodule within tarsal plate (Meibomian cyst) -> Inflammation (redness, bump) of eyelid gland that has been clogged
If Infected –> + painful
Complications of chalazion
- Orbital cellulitis
- Pre-septal cellulitis
- Cavernous sinus thrombosis
- Mass effect on cornea causing astigmatism and BOV
Treatment of chalazion
- Self-resolves within several days to weeks
- Lid hygiene
- Warm compress and topical Abx
- Incision and curettage if recurrence
Stye
- Staph aureus abscess of lash follicle and its associated gland
- Red, swollen, painful, tender nodule in lid margin pointing through skin
Tx with hot compress, epilation of lash a/w the infected follicle and topical Abx ointment
Symptoms of chalazion
Hard, firm
Painless (unless infected)
Nodule over the tarsus
Difference between chalazion and stye
Cause
Chalazion is due to inflammation of an eyelid gland that has become clogged but is not infected
Stye is due to a bacterial infection of a lash follicle in the eyelid by Staphylococcus aureus
Symptoms
Chalazion is a firm, non-tender, painless (if not infected) lump while stye is painful, swollen and tender to touch
Location
Stye is most commonly found at or near eyelash follicle while chalazion is most commonly found above eyelashes of upper lid
*chalazion is more obvious when eyelid is inverted
Preseptal vs orbital cellulitis
Orbital cellulitis is the infection of the ocular adnexal tissue posterior to the orbital septum while preseptal cellulitis is infection that only involves structures anterior to the septum, such as eyelid tissue.
Causes of orbital/preseptal cellulitis
Adjacent infection in surrounding structures
- Sinusitis (ethmoid/maxillary)
- Eyelids (stye/chalazion)
- Lacrimal sac
- Dental infections
External causes
- Trauma (bites)
- Surgery
Pathogens
- Haem influenza B
- Staph aureus
- Strep pyogenes
Ophthalmic causes (e.g. endophthalmitis with extraocular extension)
Symptoms of preseptal cellulitis
Pain of the eyelid
Eyelid redness and swelling
Induration
*NO eye involvement
Symptoms of orbital cellulitis
Symptoms of preseptal cellulitis
AND
- Proptosis
- Chemosis
- thickened eyelid
- Ophthalmoplegia -> Double vision
- Decreased visual acuity -> BoV*
- Pain on eye movements + EOM involvement*
- RAPD
- Fever
Treatment of preseptal cellulitis
PO Augmentin
Warm compress
Topical Abx
Management of orbital cellulitis
Admit, refer
Analgesia
FBC, gram stain & culture
CT scan of sinuses and orbits
- confirm ddx
IV Abx (Ceftriaxone/ Vancomycin)
Resolve underlying etiology
Surgery to drain abscess
What classification to be used for preseptal/orbital cellulitis?
Chandler’s classification
- describes level of involvement of cellulitis
Stages of Chandler’s classification
Stage 1: Preseptal cellulitis
Stage 2: Orbital cellulitis
Stage 3: Subperiosteal abscess
Stage 4: Orbital abscess
Stage 5: Cavernous sinus thrombosis
Pertinent examinations to do in eye cellulitis
Pupils
RAPD
EOM
VA, VF
Color vision
Chemosis
Proptosis
Complications of orbital cellulitis
Optic nerve compression
Subperiosteal or orbital abscess
Meningitis
Cavernous sinus thrombosis
Types of allergic conjunctivitis
Seasonal/perennial conjunctivitis
Atopic keratoconjunctivitis (AKC)
Vernal keratoconjunctivitis (VKC)
Symptoms of allergic conjunctivitis
- Intense itch**
- Intermittent history of red eyes
- Lid swelling and redness (the CONJUNCTIVA is superficial, not vessels)
- Watery/ mucoid discharge
- Thick ropy mucoid discharge
- Background of other atopies
Clinical signs in allergic conjunctivitis
Conjunctival chemosis
Conjunctival injection
Epithelial erosions or epithelial defect
Papillae or cobblestone papillae
Horner trantas dots
Limbitis
Shield ulcer
Examination findings for vernal keratoconjunctivitis
Giant papillae of only superior tarsal conjunctival
Limbitis
Shield ulcer
Examination findings for atopic keratoconjunctivits
Papillary hypertrophy of superior and inferior tarsal conjunctival with increased risk of eyelid thickening and scarring
Chronic changes/cx of untreated VKC or AKC
Loss of eyelashes
Conjunctival scarring
Corneal neovascularization
Corneal ulcer
Corneal scarring
Keratoconus
Management of allergic conjunctivitis
Systemic management
- Allergen avoidance
- Skin prick test
- Control of other allergies
Ocular management
- Topical mast cell stabilisers
- Topical anti-histamines
- Topical lubricants
- Cold compress
- Topical steroids
- Topical immunomodulators — cyclosporin, tacrolimus
- Systemic steroids in severe cases
- Supratarsal injection of steroid for recalcitrant cases
Most common causative virus of viral conjunctivitis
Adenovirus
Symptoms of viral conjunctivitis
- Conjunctiva intensely hyperemic (Red eyes)
- Sticky watery muco-serous discharge
- Tearing
- Burning sandy gritty feeling in eye
- Recent URTI
- Contact history
- Usually starts in one eye then moves to other eye
Signs of viral conjunctivitis
- Conjunctival injection
- Conjunctival follicular reaction
- Pseudomembranes seen on lid eversion
- Check for corneal involvement — punctate epitheliopathy, epithelial defect
Complications of viral conjunctivitis
- Corneal epitheliopathy
- Keratitis
Treatment for viral conjunctivitis
Self-resolving
Very contagious!
Topical lubricants
Topical steroids for keratitis if risk of scarring
Common causative organisms of bacterial conjunctivitis
Staph aureus
Staph epidermidis
Strep pneumoniae
Haemophilus influenzae
Risk factors of bacterial conjunctivitis
- Contact lens usage
- Swimming in contaminated waters
- Risky sexual lifestyle (Gonorrhea/ Chlamydia)
Symptoms of bacterial conjunctivitis
Redness
Grittiness
Burning
Extensive mucopurulent discharge
Bilateral
‘Eyes stick together’
Signs of bacterial conjunctivitis
- Crusty lids
- Conjunctival hyperaemia
- Purulent discharge from eye
- Mild papillary reaction
- Lids and conjunctiva may be oedematous
Treatment for bacterial conjunctivitis
- Stop using contact lens/ swimming
- Topical Abx (Chloramphenicol/ Erythromycin)
Common causative virus of viral keratitis
HSV 1
HSV 2
Varicella zoster virus
What is herpes simplex keratitis?
- Reactivation of latent HSV type 1
- Migrates down branch of trigeminal nerve to cornea (Esp nasociliary branch)
Look for ‘Hutchinson’s Sign’ (Tip of nose)
Symptoms of herpes simplex keratitis
Red eye
Tearing
Photophobia
Pain
Hyperaemia
BoV
Watery discharge
Risk factors of herpes simplex keratitis
Immunocompromised states
Signs of herpes simplex keratitis
- Corneal sensation reduced (Touch with cotton wool)
- Conjunctival injection
- Dendritic corneal ulcer with terminal bulb: Faint branching grey opacity on penlight examination, best seen stained with fluorescein
- Geographic ulcer (coalesce of multiple dendritic ulcers)
Treatment for herpes simplex keratitis
Topical acyclovir
PO acyclovir
- immunocompromised patients
- long term prophylactic treatment of recurrent HSV keratitis1
Complications of herpes simplex keratitis
Recurrence
- remains latent in trigeminal ganglion
What is herpes zoster ophthalmicus?
Caused by reactivation of varicella zoster virus and manifests as a unilateral painful vesicular rash along the ophthalmic division (V1) of the trigeminal nerve
Signs of herpes zoster opthalmicus
Vesicular or pustular rash seen along the V1 dermatome distribution
- Hutchinson’s sign: involvement of tip of the nose due to involvement of the nasociliary branch of V1 of trigeminal nerve
Risk factors of herpes zoster ophthalmicus
Advanced age
Stress
Immunocompromised
Common organisms for bacterial keratitis
Pseudomonas aeruginosa
Staphylococcus aureus
Streptococcus
Risk factors of bacterial keratitis
Poor contact lens hygiene
Trauma
Contaminated water contact with eye
Signs of bacterial keratitis
- Conjunctival injection
- Corneal ulcer
- Whitish Cornea opacity (Round white spot); Stain with fluorescein
- Hypopyon
- Corneal edema
Immediate investigation for bacterial keratitis
Cornea scrapings for gram stain and culture
Immediate management for bacterial keratitis
- Refer ophthal immediately!
- Topical Abx Cefazolin + Topical Gentamicin→ applied every hour
- Topical cycloplegia
Complications of bacterial keratitis
Corneal perforation
Corneal scar
Blindness
Endophthalmitis
Endophthalmitis
Bacterial or fungal infection within the eye involving vitreous/aqueous humour
!medical emergency!
Causes of endophthalmitis
- Trauma
- FB
- Acute post cataract surgery
- Extension of keratitis
Symptoms of endophthalmitis
Red and painful eye
Severe vision loss
Signs of endophthalmitis
- Diffuse conjunctival injection
- Hypopyon
- RAPD
- Loss of red reflux
- Presence of vitritis
- Chemosis
- Hazy cornea from corneal edema
How to differentiate between keratitis and endophthalmitis?
B-scan ultrasonography to check for vitreous involvement
Investigations for endophthalmitis
- Vitreous tap sent for culture and gram stain
- Blood culture if septic shock
Treatment of endophthalmitis
- Give intravitreal Abx straightaway (Tap and inject)
Vancomycin
Ceftazidime - Give topical and systemic Abx
- Vitrectomy
Common causative organisms in endophthalmitis
Strep (Endocarditis)
Staph (Cutaneous infx)
Bacillus (IVDU)
Candida
Treatment for stye
Warm compress
Lid hygiene
Epilation of lash a/w the infected follicle
Topical Abx ointment
How to differentiate viral and bacterial conjunctivitis?
Viral
- watery discharge
- unilateral
- self-limiting
Bacterial
- mucopurulent discharge
- bilateral
- topical abx
Distinguishing feature of viral conjunctivitis
- Starts in one eye and rapidly spreads to the other eye
- Self limiting within a week or so, supportive management is enough
Distinguishing sign of HSV keratitis
Dendritic corneal ulcers that stain with fluorescein
Distinguishing feature of keratitis
Whitish corneal opacity
Distinguishing feature between preseptal vs orbital cellulitis
Orbital cellulitis is distinguished from preseptal cellulitis by pain with ocular movements and vision changes
Difference between orbital vs pre-septal cellulitis
Preseptal cellulitis
- Disease of infant/toddler (20 months old)
- Presents with redness and edema but NO vision loss or pain on eye movements
- Treat with co-amoxiclav
Orbital cellulitis
- POST SEPTAL cellulitis which tracts from the ethmoidal sinus
- Presents with more systemic and severe effects such as fever, pain with eye movements, ophthalmoplegia and ptosis
- Medical emergency and treat with IV ceftriaxone or vancomycin
What type of drugs is contraindicated in keratitis?
Corticosteroids
- can cause immunosuppression and worsen the infection
