Ultrasonographic Characteristics and Pathological Findings of Murine Impaired Kidneys by Feeding Melamine Food

Objective To observe the ultrasonographic characteristics and pathological findings of murine impaired kidneys by feeding melamine food.Methods SD rats were randomly divided into two groups: control group and study group,20 rats in each group.Control group were fed with routine rat food,and study group were fed with rat food fixed with melamine(400mg/kg bw).After feeding for 20 days,sonogram of rat kidneys were performed,biochemical samples were texted,and eventually rat kidneys were taken out for microscopic observation.Results Control group showed no abnormal findings in pathology,biochemics and sonography.In study group all 20 rats showed enhanced echoes of kidney parenchyma with multiple echogenic spots,some with stone shadow.8 kidneys demonstrated hydronephrosis;20 rats had crystals in urine,liquid chromatography of urine showed melamine,cyanuric acid and uric acid.20 rats had elevated urea value,10 rats had elevated Cr value,and 14 rats had lower CO2CP value;all rats had various abnormal pathological findings,typical lesions including extensive congestion with focal bleedings in th renal tissue,spoted tubule necrosis with fibroblasts proliferation,some tubules dilated and filled with melamine crystals,several lymphocytes infiltration in some areas of renal parenchyma.Conclusion Melamine can damage rat kidney and forms stones,resulting in renal failure.Sonography is able to show those abnormal changes.