In patients with immunological disorders, adenovirus infections are associated with significant rates of morbidity and mortality. Only few hematological units use molecular virological methods, such as polymerase chain reaction, for surveillance of adenovirus infection, and treatment strategies have never been evaluated in multicenter clinical trials. This report describes the detection and treatment of human adenovirus (HAdVs) disseminated disease in the case of a 46-year-old immunocompromised female having myelodysplastic syndrome with refractory cytopenia with multilineage dysplasia: International Prognostic Scoring System 1. Serum and urine samples were tested for the presence of adenoviral DNA using the quantitative real-time polymerase chain reaction (PCR) assay. For additional confirmation, sequencing of PCR products was also performed. With real-time PCR, we detected HAdV DNA in both serum and urine samples. The viral level constantly decreased with applied oral ribavirin therapy. As the result of sequencing, HAdVs type 11 was determined. Surveillance of adenovirus by real-time PCR is useful in detecting and monitoring disseminated HAdV infection; it is a potential standard diagnostic approach that could assist clinicians to decide whether antiviral therapy ought to be administered.