IgG < 75
New to immunology. 57 y/o male with a history of multiple complicated diverticulitis flares, sepsis, sigmoidectomy, and severe persistent asthma. Doc wanted to explore reasons for frequent infections. Found out this week from labs that my IgG <75. My IgA and IgM are normal. Had labs in 2023 for asthma testing and my IgG was in the 900s. Went septic from a bad diverticulitis episode in 2024. Had my sigmoid colon removed in 2025. Just recovered from another diverticulitis flare in another part of my colon. Doc was alarmed by my labs and referred me for an "urgent" immunologist appointment on Monday. From what I've been reading, IVIG or SCIG are the likely next steps. I know it's a basic question, but what should I expect during the next few weeks? Thanks for any information you have.