Final answer:
Hemolytic Uremic Syndrome (HUS) is the main cause of acute renal failure in children that causes bloody diarrhea.
Step-by-step explanation:
One of the main causes of acute renal failure in children, specifically causing bloody diarrhea, is Hemolytic Uremic Syndrome (HUS). This condition often presents after gastrointestinal infection, particularly with the bacterium Escherichia coli (E. coli), which produces toxins leading to the destruction of red blood cells, a drop in platelet count, and acute kidney injury. The resulting red blood cell fragments can clog the kidney's filtering system, leading to a form of kidney failure.
Another possible cause is Henoch-Schonlein Purpura (HSP), however, HSP typically involves a rash (purpura), joint pain, and abdominal pain, in addition to possible kidney involvement. IgA Nephropathy, also known as Berger's disease, usually manifests with blood in the urine rather than diarrhea and is the result of IgA deposits in the kidneys. Acute Glomerulonephritis (AGN), while a cause of acute kidney injury, doesn't specifically present with bloody diarrhea as a primary symptom.