The main difference is in how quickly they happen. Chronic renal failure comes on gradually and is not noticeable in its early stages. Acute renal failure is something that happens suddenly. This happens over a few hours or a few days.
For detailed information on both, please follow these links:
If acute renal failure is often a reversible process, chronic renal failure refers to a progressive deterioration of renal function, up to its complete loss, when survival is no longer possible only with devices that replace the renal function or if it is performed a kidney transplant.
The main diseases that can lead to the chronic renal failure are: diabetes mellitus, chronic glomerulonephritis, vascular renal disease (renal artery thickening, mostly due to atherosclerosis), etc. .