ESPN 51th Annual Meeting

ESPN 2018


 
Early diagnosis of Fanconi-Bickel Syndrome identified by neonatal screening for galactosemia in Lithuania
RIMANTE CERKAUSKIENE 1 AGNE CERKAUSKAITE 2 RUGILE JURKYTE 2 JURGITA SONGAILIENE 3

1- VILNIUS UNIVERSITY, FACULTY OF MEDICINE AND COORDINATING CENTRE FOR CHILDREN’S RARE DISEASES, CHILDREN‘S HOSPITAL, VILNIUS UNIVERSITY HOSPITAL SANTAROS KLINIKOS, VILNIUS, LITHUANIA
2- VILNIUS UNIVERSITY, FACULTY OF MEDICINE
3- DEPARTMENT OF HUMAN AND MEDICAL GENETICS, VILNIUS UNIVERSITY FACULTY OF MEDICINE
 
Introduction:

Fanconi-Bickel syndrome (FBS, MIM #227810) is rare autosomal recessive disorder of glucose metabolism. It is caused by defects in the facilitative glucose transporter 2 (GLUT2) encoded by SLC2A2 gene. Clinical manifestations of FBS include fasting hypoglycemia, postprandial hyperglycemia and proximal renal tubular dysfunction. However, it represents a diagnostic challenge, because those symptoms rarely present from birth. Even though, diagnose is not based on neonatal screening for galactosaemia, but testing results may suggest FBS.

Material and methods:

The patient, now 3 months old, is a female born to healthy nonconsanguineous parents.

Results:

Her birth weight was small for gestational age, but other than that she did not have any noticeable symptoms of metabolic disorder. The newborn screening revealed elevated total galactose to 30 mg/dL (cut off <10mg/dL). Repeated analyses revealed that total galactose has increased to 140 mg/dl, therefore galactose free diet was initiated. During the initial consultation, the patient had normal physical examination and normal alanine aminotransferase level. No mutations were detected in a GALT gene. Subsequent investigations revealed massive glucosuria, proteinuria and hyperaminoaciduria. Due to massive glucosuria molecular genetic analysis of SLC2A2 gene was performed and homozygous single nucleotide deletion in exon 11 c.1469delA was identified. This confirmed the clinical diagnosis of FBS. Only at the age of 3 months mild growth retardation, poor motor development and the first radiological signs of rickets (rachitic rosary) were noticed.

Conclusions:

At an early stage, clinical manifestation of FBS is not very significant; therefore, it is difficult to diagnose it. Fortunately, neonatal screening for galactosemia may result in earlier detection of FBS and it has to be confirmed by molecular genetic tests of SLC2A2 gene. With early and appropriate treatment, the overall prognosis of our patient is good.