H1N1 infection in a cohort of hematopoietic stem cell transplant recipients: prompt antiviral therapy might be life saving.

Influenza A H1N1 virus, causing a pandemic since spring 2009, has been an important cause of morbidity and mortality worldwide. Patients with hematological malignancies and hematopoietic stem cell transplant (HCT) recipients are in a high-risk group and might require hospitalization more commonly because of H1N1 infection. Early demonstration of H1N1 influenza virus and commencing antiviral therapy promptly can be life saving particularly in immunosuppressed patients. We retrospectively reviewed the data of 10 HCT recipients who were diagnosed with influenza H1N1 infection at the Stem Cell Transplantation Unit of Gazi University Hospital in Turkey, from October through December 2009. All patients, except 1, were started empirically on oseltamivir on admission, after nasopharyngeal and oropharyngeal sampling for H1N1 virus. Four of the patients, 2 of whom developed pneumonia, required hospitalization. One of the patients with pneumonia died of respiratory failure caused by bacterial co-infection. The course of the remaining patients was uneventful. In conclusion, HCT recipients infected with H1N1 during the influenza H1N1 pandemic did not necessarily have an adverse prognosis, particularly with prompt administration of the appropriate antiviral therapy.