Table 2.

Criteria for bilateral SICKa

Criteria
    small:bilaterally decreased kidney sizeb by at least one of three methods
        ellipse volume: men <93.2 cm3; women <73.9 cm3
        voxel volume: men <102 cm3; women <77.5 cm3
        parenchymal thickness: men <1.44 cm; women <1.27 cm
    indented: at least three indentations on each kidney, with at least one major indentation (≥5 mm deep) on one side
    calcified: papillary calcifications in each kidney involving at least four papillae or at least 2 mm in size
Classification
    grade 1: both kidneys are small and indented
    grade 2: both kidneys are small and calcified
    grade 3: both kidneys meet all three criteria
  • a SICK, small indented calcified kidneys.

  • b Cut points were calculated using the healthy volunteers (n = 61 for parenchymal thickness and ellipse volume, n = 30 for voxel volume) reviewed early in the study and are based on 2 SD from the mean value derived from an average of the right and left kidney values. Renal size measurements in healthy individuals were normally distributed.