Snapshot
- A 33-year-old man presents to the emergency department with new-onset vision blurriness with “flashing lights.” His symptoms began approximately 4 days prior to presentation and have progressively worsened. He occasionally sees floaters, and his symptoms affect both eyes but are more severe on the left eye. He has a past medical history of HIV infection and reports to not taking his medication for the past year. Ophthalmology was consulted and performed a dilated ocular exam. Indirect ophthalmoscopy demonstrated 1-2 yellow-white foci of disease in a perivascular distribution accompanied by retinal hemorrhage in a “brush fire” pattern. His CD4+ count is 39/uL. She is started on cidofovir and antiretroviral therapy. (Cytomegalovirus retinitis)
Introduction
- Mechanism of action
- acts as a nucleotide analog, by which it competitively inhibits nucleotide (deoxycytidine triphosphate) incorporation into viral DNA by viral DNA polymerase
- no viral kinase activity is required for activation of cidofovir (in contrast to ganciclovir)
- however, host cell kinases still required for activation
- acts as a nucleotide analog, by which it competitively inhibits nucleotide (deoxycytidine triphosphate) incorporation into viral DNA by viral DNA polymerase
- Mechanism of resistance
- altered viral DNA polymerase
- Clinical use
- cytomegalovirus (CMV) infection
- CMV retinitis
- acyclovir-resistant herpes simplex virus infections
- cytomegalovirus (CMV) infection
- Adverse effects
- dose-dependent nephrotoxicity
- monitored by checking serum creatinine and urine protein
- nephrotoxicity can be reduced with hydration and probenecid
- ophthalmologic disturbances due to toxicity to ciliary body
- iritis
- uveitis
- decreased intraocular pressure
- possible vision loss
- dose-dependent nephrotoxicity