Genitourinary Tract

Kidney Formation

• Kidney development undergoes a complicated series of formation and regression of primitive renal structures

• Final kidney is formed from interaction of the ureteric bud and specialized mesoderm, the metanephric blastema

  • Ureteric bud induces metanephric blastema to form nephrons

  • In turn, metanephric blastema induces ureteric bud to bifurcate into developing calyces

• Anomalies resulting in failure of ureteric bud to interact appropriately with metanephric blastema

  • Renal agenesis

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      Failure of ureteric bud to come into contact with metanephric blastema; no kidney is formed

  • Multicystic dysplastic kidney

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      Ureteric bud does not signal appropriate development so there is disorganized stromal expansion and cyst formation