The Impact of Pneumonia on the Course and Outcome in Patients with Seasonal Influzenza.

INTRODUCTION Seasonal influenza, although often presented as a mild, self-limiting disease, is frequently accompanied by complications that lead to the development of a severe clinical presentation and a fatal outcome. The most common are respiratory complications, with secondary bacterial pneumonia being the leading cause. AIM The aim of this study is to determine the impact of pneumonia on the severity of the clinical presentation and outcome in patients with seasonal influenza. MATERIALS AND METHODS This research is comparatively group-based and has been conducted at the University Clinic for Infectious Diseases and Febrile Conditions during a three-year period. The analysis consists of 122 adult patients with clinically and laboratory-confirmed influenza. Based on the severity of the clinical picture, the patients are divided into two groups, severe (n=87) and mild (n=35) forms of the disease. The study included demographic, general data, clinical symptoms, and signs as well as complications. RESULTS Of 122 patients with seasonal influenza, complications were registered among 108(88.52%), with a significantly more frequent emergence among the group with severe influenza 93.1% vs 77.14% (p=0.012). Pneumonia was the most common 98(80.33%) and had a significant effect on disease severity (p=0.002). Complications from the types of ABI 8(6.56%), ARDS 7(5.74%), sepsis 5(4.1%), DIC 4 (3.28%) and otitis 2(1.64%) were reported only in the group with severe influenza. Acute meningoencephalitis was registered among 5(4.1%), gastroenterocolitis among 3(2.46%), and hepatic damage among 14(11.47%) of patients. CONCLUSION Pneumonia as the most common complication among patients with seasonal influenza significantly impacts the clinical course and outcome of the illness.