We report the follow-up and treatment of HCMV infections in three patients with AIDS. The patients, affected by HCMV retinitis, have been followed 24, 12 and 6 months respectively. The antiviral treatment was based on the DHPG administration which was substituted in one case of resistance to DHPG with Foscarnet. In the follow-up period, virological tests have been performed to detect the presence of the HCMV antigenemia/viremia. The results show that, to avoid the progression of the retinitis, the antiviral treatment must not be stopped or discontinued. DHPG and Foscarnet were able to limit the infection to the eye and were well tolerated. In the HCMV-infected patients, the continuous monitoring of the antigenemia/viremia is of main importance to follow the clinical and therapeutical course of the disease.