Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

Crystalluria

Crystalluria is the excretion of microscopic crystals by urine.

Clinical Findings

The solute do not form crystals in normal urine, so the microscopic detection of crystals in urine is an abnormality. The reason may be innocuous such as in insufficent water intake, in case of some medicaments, of simply evaporation of water before microscopy. In rare cases urinary crystals indicate severe disorders. In some of these cases the diagnosis can be even mad by the picture of those crystals.

Diseases

Cystinuria
Cystein crystals show the typical form of a hexagon (benzene ring) of pale yellow color.
Dihydroxyadenin urolithiasis
DHA crystals show a typical picture by polarized microscopy: the crystals appear as round and reddish-brown, with characteristic central Maltese cross pattern.