A 38 y.o. woman complains of a purulent discharge from the left nostril. The body temperature is 37,5°C. The patient has been ill for a week and associates her illness with common cold. There are a pain and tenderness on palpation of her left cheek. The mucous membrane in the left nasal cavity is red and turgescent. The purulent exudate is seen in the middle meatus in maxillary. What is the most probable diagnosis?