[Persistent microhematuria: localization of the source of bleeding by the evaluation of erythrocyte morphology].

Evaluation of erythrocyte morphology enables differentiation between renal-parenchymatous and postrenal microhematuria. In case of renal erythrocyturia, further examination is carried out with a nephrologist following abridged urologic examination. If the erythrocytes in the urinary sediment are established as being unchanged (postrenal cause of bleeding), a complete urological check is carried out. Today, renal-parenchymatous erythrocyturia can be established with great certainty without a kidney biopsy.