Nephrocalcinosis in glucose-galactose malabsorption: nephrocalcinosis and proximal tubular dysfunction in a young infant with a novel mutation of SGLT1.
We report an association of proximal renal tubular dysfunction in a 50-day-old girl with glucose-galactose malabsorption who was found to have nephrocalcinosis, but no sign of nephrolithiasis. A novel homozygous nonsense mutation at 267Arg-->stop (CGA-->TGA) in the Na(+)-dependent glucose transporter (SGLT1) was found in loop 5 connecting transmembrane segments 6 and 7, indicating the complete loss of glucose transport activity. This case indicates that hypercalcaemia, nephrocalcinosis and proximal tubular dysfunction may be seen in association with glucose-galactose malabsorption and that most of these abnormalities improve with a glucose-galactose-free diet.
Soylu
Ozlem Bekem
OB
Department of Pediatrics, Dr. Behçet Uz Children's Hospital, Izmir, Turkey. obekem@yahoo.com
Ecevit
Ciğdem
C
Altinöz
Serdar
S
Oztürk
Aysel Aydoğan
AA
Temizkan
Ali Kemal
AK
Maeda
Mari
M
Kasahara
Michihiro
M
D005198:Fanconi Syndrome / Q000150:complications* / Q000235:genetics; D005260:Female; D005690:Galactose / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D044882:Glucose Metabolism Disorders / Q000150:complications* / Q000235:genetics; D006801:Humans; D007223:Infant; D008286:Malabsorption Syndromes / Q000150:complications* / Q000235:genetics; D020125:Mutation, Missense; D009397:Nephrocalcinosis / Q000209:etiology* / Q000235:genetics; D051269:Sodium-Glucose Transporter 1 / Q000235:genetics*
D051269:Sodium-Glucose Transporter 1; D005947:Glucose; D005690:Galactose