10–3.34). Quantitative CMV DNA detected in the plasma of HIV-infected patients with CD4 counts ≤100 cells/μL is a predictor for HIV disease progression, CMV disease Depsipeptide in vitro and death. A single low value of 80 copies/mL identifies patients at low but significantly increased risk during the following months, after the measurement. Infection with cytomegalovirus (CMV) is a major cause of morbidity in HIV-positive patients [2]. Although the introduction of highly active antiretroviral therapy (HAART) has led to a decline in the incidence of opportunistic diseases

(ODs) in general, including CMV infection, CMV end-organ disease continues to occur in HIV-infected patients failing HAART because of adherence problems or drug resistance, or presenting late with low CD4 cell counts [3–5]. Most studies on CMV were conducted in the pre-HAART era, using

methods with high thresholds for viral detection. They showed that detection of CMV in plasma predicts CMV disease in persons with advanced AIDS [2,6]. Prophylactic use of oral ganciclovir reduced the risk of CMV disease [7,8]. Between 1996 and 2003, new studies suggested that CMV plasma viral load predicts CMV retinitis [9] and that a high CMV plasma viral load is associated with an increased risk of death [10], while successful HAART suppresses CMV viraemia [11]. Nevertheless, CMV viraemia is often detected in patients with low CD4 cell counts who do not develop CMV disease after starting HAART [9,12]. In acutely ill HIV-infected patients, detection of CMV viral load by quantitative PD0332991 supplier polymerase chain reaction (PCR) was found to be a poor predictor of CMV end-organ disease: 43.5% of the patients presented with positive viraemia, but only 7.4% had end-organ CMV disease [13]. Recently, new quantitative PCR assays have been developed GBA3 with increased sensitivity. The threshold of detection has decreased from 400 to 20 copies/mL in plasma. With this increased sensitivity we have often found CMV viraemia in HIV-infected patients, sometimes with elevated, albeit fluctuating CMV DNA levels,

but without any evidence (in cultures or biopsies) of CMV end-organ disease. In this study, we therefore evaluated the prognostic value of an early positive CMV viral load, using an ultrasensitive PCR (detection limit 20 copies/mL), for global mortality, CMV end-organ disease and other ODs in HIV-infected patients with CD4 counts ≤100 cells/μL. We also describe the incidence and prevalence of CMV end-organ disease in the Swiss HIV Cohort Study (SHCS) since 1996. We included patients followed in the SHCS (http://www.shcs.ch) after 1 January 1996 who had detectable CMV-specific immunoglobulin G (IgG), a CD4 cell count ≤100 cells/μL measured after or at the same time as the diagnosis of CMV seropositivity, and a frozen plasma sample available in the interval of 3 months before to 1 month after the CD4 cell count for the measurement of baseline CMV DNA.