Kidney
…ting renal dysfunction. Markers of GFR:Â Urea nitrogen, creatinine, cystatin C, symmetrical dimethylarginine (SDMA). This is most accurately measured with clearance tests, such as inulin clearance. Urinalysis: In particular urine specific gravity (which tells us about tubular function), urine sediment examination (cells, crystals and casts), chemical constituents (tells us tubular and general body metabolic function) and gross features….