Hi, recently diagnosed officially w/ cvid. Is there success w/ xylitol nasal rinses to prevent sinus infection when I catch a cold? Don't want ivig tx

May be. Nasal rinses with xylitol may be more effective than simple saline solutions. They may not prevent sinusitis, but will help reduce their occurrence. This does not mean that you do not need replacement ig. That depends on what your overall symptoms, what kind of infections you had and so forth. Even if you need igg, it can be given by subcutaneous infusion (into the skin of the abdomen or thigh).