Cysts can arise through a variety of processes in the body, including.  1 wear and tear or simple obstructions to the flow of fluid, 2  infections, 3  tumors, 4  chronic inflammatory conditions, 5  genetic (inherited) conditions,  defects in developing organs in the embryo.
1 Acute * sinusitis often develops after a person has had a cold, with symptoms lasting less than 3 weeks. 2  Chronic * sinusitis can last 3 to 8 weeks or longer; it often occurs in people who have allergies or asthma. 3  Recurrent sinusitis consists of several acute episodes of sinusitis in 1 year.
Causes of Sinus Infection. Knowing the causes of sinus infection is beneficial to the patient and the layman for prevention of recurrent sinus infections! The most common cause of a sinus infection is the common cold, viral influenza and hay fever. The cold causes inflammation in the nasal passages and this inhibits the drainage of the sinuses which can cause them to become inflamed. When we have flu, our nose is filled with mucus.