Sandbox jyostna
Retinitis HIV+ (AIDS) CD4 usually <100/mm3 Cytomegalovirus See Table 14, page 146 Occurs in 5–10% of AIDS patients Most common cause of blindness in AIDS patients with <50/mm3 CD4 counts. 19/30 pts (63%) with inactive CMV retinitis who re-sponded to HAART (Ĺ of ≥60 CD4 cells/mL) developed immune recovery vitreitis (vision Ļ & floaters with posterior segment inflammation —vitreitis, papillitis & macular changes) an average of 43 wks after rx started (JID 179: 697, 1999). Corticosteroid rx Ļ inflammatory reaction of immune recovery vitreitis without reactivation of CMV retinitis, either periocular corticosteroids or short course of systemic steroid. For immediate sight-threatening lesions: Ganciclovir intraocular implant & valganciclovir 900 mg po q24h. For peripheral lesions: Valganciclovir 900 mg po q12h x 14–21d, then 900 mg po q24h for maintenance therapy Ganciclovir 5 mg/kg IV q12h x 14–21d, then valganciclovir900 mg po q24h OR Foscarnet 60 mg/kg IV q8h or 90 mg/kg IV q12h x 14–21d, then 90–120 mg/kg IV q24h ORCidofovir 5 mg/kg IV x 2wks, then 5 mg/kg every other wk; each dose should be administered with IV saline hydration & oral probenecid OR Repeated intravitreal injections with fomivirsen (for relapses only, not as initial therapy) Differential diagnosis: HIV retinopathy, herpes simplex retinitis, varicella-zoster retinitis (rare, hard to diagnose). Valganciclovir po equal to GCV IV in induction of remission: (NEJM 346:1119, 2002). Cannot use ganciclovir ocular implant alone as approx. 50% risk of CMV retinitis other eye at 6 mos. & 31% risk visceral disease. Risk Ļ with systemic rx but when contralateral retinitis does occur, ganciclovir-resistant mutation often present (JID 189:611, 2004). Concurrent systemic rx recom-mended! Because of unique mode of action, fomivirsen may have a role if isolates become resistant to other therapies. Retinal detachments 50–60% within 1yr of dx of retinitis. (Ophthal 111:2232, 2004). Equal efficacy of IV GCV & FOS. GCV avoids nephrotoxicity of FOS; FOS avoids bone marrow suppression of GCV. Although bone marrow toxicity may be similar to ganciclovir. Oral valganciclovir should replace both.
Patients who discontinue suppression therapy should undergo regular eye examination for early detection of relapses.Post treatment suppression (Prophylactic) if CD4 count <100/mm3: Valganciclovir 900 mg po q24h. Discontinue if CD4 >100/mm3 x 6 mos on
Herpesvirus Infections Cytomegalovirus (CMV)
Marked decrease in HIV associated CMV infections & death with Highly Active Antiretroviral Therapy. Initial treatment should optimize HAART.
Primary prophylaxis not generally recommended. Preemptive therapy in patients with increased in CMV DNA titers in plasma & CD4 <100/mm3. Recommended by some: valganciclovir 900 mg po q24h. Authors rec. primary prophylaxis be dc if response to HAART with incerase in CD4 >100 for 6 months.
Risk for developing CMV disease correlates with quantity of CMV DNA in plasma: each log10Ĺ associated with 3.1-fold increase in disease.