Fractures of the frontal bone can interfere with the drainage of the frontal sinus and can cause sinusitis.

Rhinoliths can cause nasal obstruction, epistaxis, headache, sinusitis and epiphora.

Fungi can also cause chronic sinusitis.

Fungal infections may also cause sinusitis.

Allergies, pollutants, nasal problems and certain diseases can also cause sinusitis.

Allergic rhinitis can also cause long-lasting (chronic) sinusitis or inflammation of the sinus cavities.

These bacteria are known to cause otitis media, bronchitis, sinusitis, and laryngitis.

The swelling of your nasal membranes may also close the sinus drainage openings, causing sinusitis.

Streptococcus mutans, a common oral bacteria discussed above, is a pathogen that causes pneumonia, sinusitis, otitis media, and meningitis.

Some patients have a severe immunodeficiency characterized by pancytopenia, causing chronic respiratory infections and sinusitis.