Periplasmic proteinuria is also known as light chain urine, both belong to a different name for the same substance, i.e., urinary free light chains are periplasmic proteins, and when periplasmic proteinuria occurs, you should seek medical attention.
The periplasmic protein is the free light chain in immunoglobulin, when the immunoglobulin abnormality in the organism, it can lead to the imbalance of the synthesis of the light chain and the heavy chain, and when the excessive light chain exceeds the proximal convoluted tubular reabsorption threshold, the light chain can be discharged from the urine, which leads to the light chain urination, i.e., the periplasmic proteinuria, so the urinary free light chain is the periplasmic protein.
When periplasmic proteinuria occurs, it may be associated with diseases such as multiple myeloma and macroglobulinemia, and the cause needs to be clarified under the guidance of a doctor so that it can be treated aggressively.