Chronic sinusitis is a very common problem in the United States, and occurs even more frequently in people with allergies. Not all forms of sinusitis respond to antibiotics, however. A large number of people with chronic sinusitis are actually suffering from fungal sinus infections, which won't get better with typical antibiotics. There are a variety of forms of fungal sinusitis, including allergic fungal sinusitis, fungus ball, and invasive fungal sinus infections that occur in people with suppressed immune systems. If you've had chronic sinus infections, especially with symptoms that don't get better with typical treatments, you could have a fungal sinus infection. Read more about fungal sinusitis, including the symptoms, diagnosis and treatments available for each type.