In patients with intra-renal renal failure, proteinuria is typically:

Intra-renal renal failure, often caused by damage to the kidney's nephrons due to conditions such as acute tubular necrosis or glomerulonephritis, generally leads to varying levels of proteinuria. The correct understanding is that proteinuria in this context is typically moderate.

This is because when the renal tubules are damaged, they lose some ability to reabsorb proteins normally filtered by the glomeruli. As a result, proteins spill into the urine. However, the extent of proteinuria can depend on the underlying cause of the intra-renal failure; severe damage may result in more significant protein loss, but it does not typically reach the levels seen in conditions like nephrotic syndrome.

In contrast, high levels of proteinuria would suggest a more severe dysfunction of the glomeruli, while low proteinuria may indicate only minimal damage or less severe forms of renal impairment. Nonexistent proteinuria would suggest either normal kidney function or that damage is not significant enough to lead to any protein leakage into the urine. Therefore, the moderate level of proteinuria aligns with the characteristics of intra-renal failure more accurately.