Zurlo and colleagues' [1] statement that "no systematic study has been done of whether culture positivity is predictive of current or subsequent CMV (cytomegalovirus) end-organ disease" is incorrect [2, 3]. We believe that the data presented by Zurlo and colleagues corroborate previous work and support the clinical utility of CMV cultures in patients with human immunodeficiency virus (HIV) infection.

Salient results include the findings that 31.9% of patients with CMV viruria compared with 9.3% without viruria (P = 0.02) developed end-organ disease; that the difference in rates when end-organ disease was diagnosed within 6 months of viruria was 23.1% (P = 0.008); and that patients with CMV viruria who developed end-organ disease did so sooner (95.9 ± 30.5 days) than those who did not (361.9 ± 130.4 days). In patients with documented CMV end-organ disease, 88% had viruria; of the subgroup with retinitis, 100% had viruria at the time of diagnosis.

Although CMV viremia did not correlate with the presence of either fever or weight loss in this study, the analysis did not exclude patients in whom other causes for these findings were determined. A correlation of CMV culture results with fever and weight loss of undetermined cause might have better addressed the question of the culture's clinical utility.

In patients with HIV-1 infection and a CD4 lymphocyte count less than 200 cells/mm³, CMV is an important cause of morbidity and mortality. The presence of CMV viruria should heighten compliance with obtaining ophthalmologic examinations for detection of asymptomatic retinitis and increase the clinician's suspicion of CMV end-organ disease when consistent clinical findings are not otherwise explained. Additionally, in patients with a CD4 lymphocyte count of less than 100 cells/mm³, the data provide a rational basis for considering a course of systemic therapy during a period of preclinical involvement with CMV to prevent overt end-organ disease.