The tubular vacuolization and tubular dilation here is a result of the toxic effect of ethylene glycol poisoning. This is representative of acute tubular necrosis (ATN), which has many causes. ATN resulting from toxins usually has diffuse tubular involvement, whereas ATN resulting from ischemia (as in profound hypotension from cardiac failure) has patchy tubular involvement.
Another example of toxic ATN is shown below. Skeletal muscle injury may trigger rhabdomyolysis that can be detected by urine dipstick analysis as positive blood, but no red blood cells on urine microscopic examination. This is explained by the presence of myoglobin, which gives the urine a dark brown appearance. Myoglobin is protein, accounting for the 1+ dipstick measurement for protein. With rhabdomyolysis, the serum creatine kinase will be elevated.
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Leukocyte esteraseNitrite pH Protein Blood Specific gravity Ketones GlucoseBilirubin