Children's toxicology from bench to bed--Drug-induced renal injury (4): Effects of nephrotoxic compounds on fetal and developing kidney.

The kidney is a major target of toxic compounds. Susceptibility of the kidney to toxic effects of compounds is attributed to the unique morphologic and physiologic features of this organ. Renal development and maturation begins in the fetal period and continuous throughout the postnatal period. The effects of noxious compounds on the kidney are influenced by the state of renal development and maturation. Therefore, to asses the renal toxic potential of a compound in fetuses and infants, the development and maturation of the kidney should be taken into account. Renal development and maturation involves both morphological and functional aspects. Renal development begins in the fetus and proceeds to partial functional capacity before birth. After birth, the kidney continues morphologic and functional maturation during the postnatal period of infancy. The fetal or infant kidney is vulnerable to the renal toxicity of certain compounds due to its morphological and functional characteristics. On the other hand, the infant kidney is sometimes more tolerant to nephrotoxic compounds compared to the adult kidney because of its immature glomerular filtration, concentrating capability and active transportation. Design and interpretation of studies in fetuses and infants regarding renal toxicity should include careful consideration of the state of renal development and maturation and of the mechanisms of renal injury.