Can chostochondritis cause swelling? And maybe abdomen pain?

Yes but is atypical . Costochondritis or inflammation of the cartilage around the rib cage and sternum may cause swelling. I would expect the site of inflammation to be painful and swollen (point tenderness and swelling). This diagnosis may also cause back and abdominal pain, also known as referred pain. However, true abdominal pain should also be observed for worsening as it can be from other causes. .