Pandemic 2009 H1N1 influenza in patients with hematopoietic stem cell transplantation and hematologic malignancy: single center experience.

Although valuable information on many aspects of the pandemic 2009 H1N1 influenza came to light in a relatively short period of time, the disease course among immunocompromised patients is largely unknown. In this study, we present the results of active H1N1 surveillance in 32 patients who were treated at our hematology/stem cell transplantation clinic between December 2009 and January 2010. We also report the clinical and laboratory features of patients with laboratory-proven disease and try to define the impact of novel H1N1 disease on their outcome. Eight patients in the hematology clinic and 7 patients in the hematology/stem cell transplantation unit tested positive for pandemic H1N1 infection. Patients were treated with oral oseltamivir for 5-15 days. In 10 patients the infection was limited to the upper respiratory tract. But in 5 patients it was complicated with lower respiratory diseases. Three of them required intensive care support with mechanic ventilation and all died during follow-up. As the clinical and radiological findings of H1N1 infection are nonspecific in nature, we should have a high index of suspicion in immunocompromised patients. Therefore, beginning empiric oseltamivir therapy while waiting for laboratory results and increasing the dose/duration of therapy in laboratory-confirmed cases could be life saving.