A 10 year old boy presents with acute onset gross hematuria, loin pain, and diarrhea. Peripheral smear examination is normal. There is no history of decreased urine output. Serum C3 levels are normal. Probable diagnosis is?

In Berger's disease (IgA Nephropathy) gross Hematuria occurs within 1-2 days of onset of an upper respiratory or GI infection (Note:skin infection leads to poststreptococcal glomerulonephritis (PSGN) and not IgA nephropathy). Mild to moderate hypeension can be seen May be associated with loin pain Normal serum levels of C3 in IgA nephropathy help to distinguish this disorder from poststreptococcal glomerulonephritis (PSGN) where serum C3 levels are low. Serum IgA levels have no diagnostic value in IgA nephropathy because they are elevated in only 15% of pediatric patients.