Sotos Syndrome and Nephrocalcinosis, a Rare But Possible Association due to Impact on Contiguous Genes

One-month old breastfeeding infant, full-term birth, with normal anthropometric measurements at birth is referred to Pediatric Nephrology due to a nephrocalcinosis. The patient presents dysmorphic features and heart disease. A metabolic study is conducted on blood and urine yielding results within normal parameters, except for renal concentration test and acidification test. At 6 months of age, patient presents overgrowth, which along with other clinical signs arouse suspicion of Sotos Syndrome. Molecular genetic testing detects heterozygous deletion in 5q35 between bands q35.2 and q35.3, affecting genes NSD1, SLC34A1 and FGFR4, which is compatible with this syndrome and with nephrocalcinosis as a rare association.