Protein in urine may be chronic nephritis, acute nephritis, acute progressive nephritis, lupus nephritis, purpura nephritis, or nephrotic syndrome. Normally, urine protein is negative when you check the urine routine, if there is urine protein in urine, it usually indicates that you are suffering from nephritis or nephrotic syndrome. There are primary nephritis, such as chronic nephritis, acute nephritis, acute nephritis, and secondary nephritis, such as lupus nephritis, purpura nephritis, and so on. This condition usually has less qualitative urine protein, usually below (++). If the amount of urine protein is more, above (++), it is considered nephrotic syndrome. Nephrotic syndrome is also divided into primary and secondary. The main secondary nephrotic syndromes are diabetic nephropathy, ANCA-associated vasculitis nephritis, and so on. Therefore, when urine protein is found in the urine, 24-hour urine protein quantification must be performed to clarify whether it is nephritis or nephrotic syndrome, and then improve the anti-nuclear antibody profile, virus-related and other corresponding tests to further distinguish the specific cause.