What is difference between sinusitis and allergic sinusitis? what is the age when u can develop sinusitis?can it develop at any age?

Sinusitis: Allergic sinusitis or rhinosinusitis means that the changes are not from a bacterial infection but the term of allergic sinusitis is vague unless referred to as allergic fungal sinusitis. Acute sinusitis may be caused by a viral or bacterial infection but chronic usually involves a bacterial infection. Sinusitis may occur at any age but many sinuses do not develop until after early infancy.