Related Subjects:
|Herpes Varicella-Zoster (Shingles) Infection
|Chickenpox Varicella Infection
|Varicella Cerebral Vasculopathy
|Herpes Viruses
|Herpes Zoster Ophthalmicus (HZO) Shingles
|MonkeyPox
|Mumps
|Measles
|Rubella (German Measles)
|Epstein-Barr Virus infection
|Cytomegalovirus (CMV) infections
|CMV retinitis infections
|Toxoplasmosis
๐๏ธ About
Cytomegalovirus (CMV) retinitis is a severe opportunistic viral infection that occurs in advanced HIV disease when the CD4 count falls below 50 cells/mm3.
Without treatment it can cause progressive, irreversible visual loss due to retinal necrosis.
๐ฆ Aetiology
- Caused by reactivation of latent CMV infection (a ฮฒ-herpesvirus) in immunocompromised patients.
- Viral replication in the retina causes haemorrhagic necrosis and inflammatory exudation.
- Can also involve the optic nerve, brain, or gastrointestinal tract in disseminated CMV disease.
๐งโโ๏ธ Clinical Features
- Occurs when CD4 < 50 cells/mm3.
- Symptoms: floaters, blurred vision, scotomas, flashing lights, ocular pain.
- May present unilaterally, but often progresses to bilateral disease.
- Fundoscopy: retinal haemorrhages and yellow-white exudates with a characteristic โpizza-pieโ or โcottage cheese and ketchupโ appearance.
- Without therapy โ rapid progression to retinal detachment and blindness.
๐ Differentials
- HIV-associated toxoplasma chorioretinitis.
- Herpes simplex or varicella-zoster retinitis.
- Ischaemic or diabetic retinopathy.
- Syphilitic or tuberculous chorioretinitis.
๐งช Investigations
- Fundoscopy โ diagnostic; โpizza-pieโ pattern of haemorrhage and necrosis.
- Visual field testing and retinal photography for monitoring.
- Ophthalmology referral for confirmation and treatment planning.
- CMV PCR on blood or ocular fluid can confirm systemic infection.
๐ Management
- ๐ก Prevention: Routine fundoscopic screening in HIV patients with CD4 < 100 cells/mm3.
- Antiviral therapy:
- Valganciclovir (oral) for induction and maintenance therapy.
- Ganciclovir IV or intravitreal (severe sight-threatening disease).
- Foscarnet or Cidofovir for resistant CMV strains.
- Start HAART after initial antiviral control to avoid immune reconstitution uveitis (IRIS).
- Close monitoring by an HIV specialist and ophthalmologist is essential.
๐ References
