Büyükkapu-Bay S, Kebudi R, Görgün Ö, Meşe S, Zülfikar B, Badur S. Respiratory viral infection's frequency and clinical outcome in symptomatic children with cancer: A single center experience from a middle-income country. Turk J Pediatr 2018; 60: 653-659.In developing countries, acute respiratory tract infections are a significant cause of morbidity and mortality in children, particularly in pediatric cancer patients. A majority of these illnesses are precipitated by viral infections. In our country, studies were conducted on the single respiratory viral infection in a pediatric hematology-oncology unit; however, the analysis of respiratory viral infections in children with cancer is lacking. The present study aimed to provide analysis of multiple respiratory viral infections and clinical outcome in children with cancer who receive chemotherapy and show signs and symptoms of respiratory tract infections. During January, 2014 and January, 2015 children with cancer under treatment who presented with respiratory tract infections were assessed for viruses by using multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR). Specimens were collected by nasal swabbing at in-patient and out-patient clinics. Overall, 72 samples of respiratory tract infection episodes, collected from children with cancer were evaluated with the simultaneous detection of 20 respiratory viruses. A respiratory viral pathogen was obtained in 56.9% samples. Rhinovirus (24.3%) and co-infection with two viruses (19.5%) were the most frequently isolated pathogens. There were four (9.6%) samples of severe pneumonia. Patients with febrile neutropenic episodes and pneumonia were hospitalized and treated with broad-spectrum antibiotics. Other non-neutropenic and mild respiratory tract infections were treated with supportive care as outpatient procedures. There were no deaths. Because there are no effective antiviral agents for certain respiratory viruses, infection control and early diagnosis are crucial in preventing the spread of infection. Clinical findings and serological results of viral respiratory tract infections help us to accurately determine the treatment approach and avoid the unnecessary use of antibiotics.