Clinical Features and Genetic Sequencing of Children with Fanconi-Bickel Syndrome.

The present paper reports 10 patients (9 families) with Fanconi-Bickel syndrome managed during 2010-2021. Patients presented with polyuria, polydipsia, hepatomegaly, rickets, and stunting at a median of 5 (3, 7.3) mo; one had transient neonatal diabetes. Glucosuria, generalized aminoaciduria, β2-microglobinuria, urinary phosphate wasting, and hypercalciuria were present in all patients; 3 patients had nephrocalcinosis. Other metabolic abnormalities included hypertriglyceridemia (n = 5/6), fasting hypoglycemia (n = 5/8), and postprandial hyperglycemia (n = 3/6). Genetic analysis showed 7 homozygous or compound heterozygous variants in SLC2A2. A pathogenic variant c.952G>A, common to 4 patients (3 families), might be a potential hotspot. At a median follow-up of 43 mo, 4 patients died at a median of 25 mo; short stature persisted in all except one patient who showed catch-up growth with uncooked corn-starch diet. The present findings suggest that the Fanconi-Bickel syndrome has a severe phenotype with an unsatisfactory outcome. A high index of suspicion for diagnosis and efforts for facilitation of dietary therapy are necessary.