Nephrocalcinosis in very low birth weight neonates: family history of kidney stones and ethnicity as independent risk factors.

Serial renal ultrasonography was performed in 50 consecutive neonates with birth weights less than 1200 gm who survived to at least 3 weeks of age. Nephrocalcinosis developed in 8 (67%) of 12 white and only 6 (16%) of 38 nonwhite infants (p < 0.01). Seven (78%) of nine infants with a family history of kidney stones had nephrocalcinosis compared with only 7 (17%) of 41 without a family history of kidney stones (p < 0.001). We conclude that nephrocalcinosis in our population of very low birth weight neonates is significantly and independently associated with a family history of kidney stones and white race.