Immune recovery uveitis is a new syndrome that occurs in some people with advanced immune suppression (usually below 50 CD4 cells/mm3) and with CMV infection in the eye after starting successful HAART. A new study in the British Journal of Ophthalmology has found that close to 50% of patients with healed CMV who do well on HAART suffer from this condition, which can lead to a moderate loss of sight.
Researchers at the AIDS Ocular Unit of the University of California studied 90 CMV-infected eyes in 63 patients between 1986 and 2000 to see how immune recovery on HAART (CD4 count above 50 cells/mm3 for at least three months) affected eyesight. Of the 90 eyes, 27 (30%) were diagnosed with CMV before HAART, 54 (60%) were diagnosed with CMV after treatment with HAART, and 9 (10%) received HAART at the time of CMV diagnosis.
Of the 48 patients whose immune systems recovered on HAART, 26 eyes (in 21 patients) were subsequently diagnosed with immune recovery uveitis. Several different eye problems were identified, three of which were significantly associated with having both increased CD4 counts and immune recovery uveitis: cystoid macular oedema, epiretinal membrane and cataracts.
Although cataracts were commonly seen in the eyes of all patients on HAART with healed CMV disease, the highest rate of cataract formation (84%) was seen in those with increased CD4 counts and immune recovery uveitis. Those whose CD4 counts did not improve had the next highest rate (64%), whereas the lowest rate was seen in those whose CD4 count improved but did not have immune recovery uveitis.
Moderate vision loss was seen more often in the eyes of people with increased CD4 counts but without retinal detachment (P
Exactly what causes immune recovery uveitis is still something of a mystery, but it is thought to be caused by the immune system's reactions against inactive CMV in the eye, rather than by CMV itself. Whatever the mechanism, the authors conclude that “in the HAART era, vision loss is still common in CMV retinitis patients.”
Further information on this site
Goldberg DE et al. Long term visual outcome of patients with cytomegalovirus retinitis treated with highly active antiretroviral therapy. Br J Ophthalmol 87: 853-855, 2003.