Melamine can cause long-term problems

CHICAGO, April 29 (UPI) -- Children with a history of consuming melamine-contaminated milk powder are at increased risk of developing kidney stones, U.S. researchers say.

Surplus melamine has been an illegal adulterant for feedstock and milk in China for several years now because it can make the milk appear to be higher in protein content by elevating the total nitrogen content.

Melamine calculus occurred mostly in infants ages 6-18 months after consuming melamine-contaminated milk powder after birth. However, the kidney stones could be effectively managed with non-invasive treatment.

In the first study, researchers analyzed the clinical data of 50 young children with double kidney stones who had a history of consuming melamine-contaminated milk powder. Using ultrasound images, the researchers find 85 percent of the cases occurred in children ages 6-18 months.

The second study analyzed the clinical data of 165 infants, ages 50 days to three years, with urinary stones who had a history of consuming melamine-contaminated milk powder.

Researchers find that the peak incidence of urinary stones was found in children ages 6-12 months. Of these patients, 50.3 percent were asymptomatic, 16.9 percent experienced painful urination, 14.6 percent had infantile colic, 10.9 percent experience decreased urine and absence of urine and 7.3 percent had blood in the urine.