Ocular OI Flashcards
In who do new cases of CMVR occur?
Late diagnosis, poor adherence, poor tolerance of treatment, failure of ART
What are the symptoms of CMVR?
In people with CD4 <50
Affects one eye first and without treatment other eye becomes affected
Floaters, blind spots, blurred vision, sudden decrease in vision
Who should be screened for CMVR and how frequently?
Dilated indirect ophthalmoscope at 3 monthly intervals in patients with CD4 <50
How is CMVR diagnosed?
Clinical diagnosis
Urgent ophthalmology review to confirm
What counts as progression of CMVR?
Extension by 750um along 750m-wide front
For who is treatment of CMVR indicated?
Incident cases
Progression or reaction of pre existing CMVR
Benefits of treatment of CMVR
Limits progression and reduces risk of blinding complications - retinal detachment, macular involvement
Prophylaxis for unaffected eye
What can be given to patients not tolerating systemic CMVR therapy?
Intravitreal injections or implants
How is CMVR treated?
Induction - 2-4 weeks
Maintainence period with lower dose until CD4 sustained >100
What is the preferred treatment for CMVR?
Oral valganciclovir preferred option - 900mg BD in induction, OD for maintenance
What should be given if oral therapy for CMVR not tolerated or issues regards adherence?
Induction - IV ganciclovir 5mg/kg bd, iv foscarnet 90mg/kg bd, weekly cidofovir 5mg/kg
Maintenance - iv ganciclovir 5mg/kg OD or 6mg/kg/day for 5 days of week, iv foscarnet 90mg/kg od daily or 120mg/kg for 5 days of week. Fortnightly cidofovir.
What monitoring is needed for people on IV ganciclovir, foscarnet or cidofovir?
All iv options can cause significant toxicities - renal and electrolyte abnormalities, bone marrow suppression
What to do if treatment for CMVR fails with oral valganciclovir?
Dose increase
Add implant or intravitreal ganciclovir
Intravitreal foscarnet is an alternative option or switch to foscarnet or cidofovir
What to consider if CMVR treatment with implant fails?
Implants do not release ganciclovir steadily so may have ceased to release active drug
Is cidofovir safe in pregnancy?
Men - do not father a child during or within 3/12 of cidofovir treatment
Women - do not get pregnant during or for 1 month after treatment
Does CMV associated IRIS happen when ARVs are started?
May occur up to many months later
Most common presentation vitritis and most likely if large retinal lesions at baseline
Immune recovery uveitis also may occur - seen at CD4 50-150 - resolves as CD4 continues to rise
Treatment for CMV IRIS
Coordination between HIV team and ophthalmology team
Often requires corticosteroids either systemically or periocularly
When should ARVs be started in context of CMVR
‘Promptly’
How should ocular syphilis be treated in HIV+ patients?
As for neurosyphilis -
14/7 procaine penicillin 1.8mu-2.4 mu im plus probenecid 500mg po qds
Benzylpenicillin 1.8-2.4g iv 4hrly for 14/7
Alternatives
Doxy 200mg BD 28/7
Amoxicillin plus probenecid
Ceftriaxone 2g im or iv for 10-14/7
40-60mg prednisolone od for 3/7 starting 24hrs before
How is ocular toxoplasma diagnosis?
Usually on clinical suspicion
Toxoplasma dna detected on pcr of intraocular fluids
Plasma and intraocular fluid antitoxoplasma antibody levels
What is the classical appearance of ocular toxoplasmosis?
Focus of retinochoroiditis adjacent to chorioretinal scar from previous infestation
Overlying vitreous haze and cellular response
Atypical presentations can include multiple large or bilateral lesions
How does ocular toxoplasmosis occur?
Reactivation of pre or post natal infection
Occurs at an earlier stage than CMV retinitis
What is the treatment for ocular toxoplasmosis?
Systemic therapy - sulphadiazine and pyrimethamine have good efficacy but issues with toxicity and DDI may limit long term use
Atovaquone also used with success
Maintenance therapy until ‘good immune recovery’ with HAART
What extra investigation needed if a patient has ocular toxoplasma infection?
MRI head to rule out cerebral disease
Symptoms of varicella zoster virus retinitis
Rapidly progressive visual loss occurring unilaterally initially
Progrsssive full thickness retinal necrosis with confluent lesions spreading inwards from retinal periphery
Immunocompromised patients may experience early macular involvement with no vitrifis
What occular syndromes can be caused by varicella zoster virus?
Progressive outer retinal necrosis syndrome (PORN)
Acute retinal necrosis syndrome (ARN)
ARN typically VZV in older patients, can be caused by HSV in younger patients
Possible complications of VZV retinitis
Retinal detachment, ischaemic optic neuropathy from vascular occlusion or optic nerve inflammation and macular involvement
Diagnosis of VZV retinitis
Vitreous sampling and analysis
Prognosis for VZV retinitis
Often disappointing - bling within weeks from macular involvement and complications such as retinal detachment
Treatment of VZV retinitis
Cidofovir probably drug of choice with or without addition of Intravitreal ganciclovir or foscarnet
Iv ganciclovir alone or in combo with foscarnet and intravitreal ganciclovir/foscarnet have been used to halt progression
