My husband has had chronic sinusitis for 20 years. He saw an ENT for several years, they would give him a strong antibiotic and prednisone, he would get better for awhile and get back they figures infection. He was sent to a immunologist & found out his IGG was low, he is now on Hizentra & levels are good. The last 6 weeks again they gave him antibiotic didn t work, then prednisone & budesonide to irrigate nose, this didn t work either, before he would at least get some relief. Has headaches, neck ache, head feels full, always the same symptons. Had several sinus cat scans that show nothing. I feel there must be something underlying they are not finding... maybe a fungi bacteria or osteomyelitis something. I read a gallium scan is best to see if there is an issue whereas sinus cat scans don t reveal everything. I would appreciate any insite. Thanks, Paula