Aim: In this study, we aimed to share our experience with 75 patients admitted to the hospital who adhered to the definition of influenza-like illness. Patients and Methods: Pandemic 2009 influenza positive and negative cases with RNA (ribonucleic acid) detected by PCR (polymerase chain reaction) method were compared in terms of age, gender and underlying disease relationships, laboratory and radiological imaging results, hospital stay and intensive care unit stay and discharge patterns. Results: There was no significant difference in sex distribution, age and chest x-ray findings between the two groups. When the CRP(C-reactive protein) and platelet levels of the groups were compared between the groups, there was a meaningful difference between them, but there was no significant difference in terms of white cell, hemoglobin, neutrophil and lymphocyte counts. The mean CRP level in the H1N1 positive group was significantly higher than the H1N1 negative group. In the H1N1 positive group, the mean platelet amount was significantly lower than in the H1N1 negative group. Conclusion: Clinical follow-up of pandemic H1N1 influenza cases is very important. Pandemic influenza (H1N1) was thought to be fatal in some cases in the underlying chronic illness.