The retroperitoneum is the area of our bodies that hold the kidney's, Aorta, and adrenal glands. There are also lymph nodes there, and in your case they are enlarged. Lymph nodes become enlarged or swollen when the body is fighting off a virus or an infection near the ones that are swollen. For example, when the lymph in the throat are enlarged, it usually coincides with a sore throat, or upper respiratory infection.
Hope that helps,
Kerry
Kerry, RN
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