In-depth phenotyping of a Donnai-Barrow XXXX helps clarify proximal tubule dysfunction.

@entity1 @entity4094 @entity8 @entity644 @entity851 @entity5766 @entity1400 @entity17892 @entity1274 @entity1714 @entity17893
BACKGROUND: The @entity17893 / @entity17892 /amnionless complex is essential for albumin and low molecular weight (LMW) protein reabsorption by renal proximal tubules (PT). Mutations of the @entity17893 gene encoding @entity17893 cause @entity8 (DB/FOAR), which is characterized by LMW @entity644 . The pathophysiology of DB/FOAR-associated @entity4094 remains unclear. CLINICAL CASE: A 3-year-old @entity1 presented with @entity851 and @entity644 . Clinical examination was unremarkable, except for a still-opened anterior fontanel and @entity1714 . Psychomotor development was delayed. At 6, she developed @entity1274 . @entity5766 was noted when she turned 12. Blood analyses, including renal function parameters, were normal. Urine sediment was bland. @entity644 was significant and included albumin and LMW proteins. Immunoblotting analyses detected @entity17892 and @entity1400 ) in the urine. Renal ultrasound was unremarkable. Optical examination of a renal biopsy did not disclose any tubular or glomerular abnormality. Electron microscopy revealed that PT apical endocytic apparatus was significantly less developed. Immunostaining for @entity17893 showed a faint signal in PT cytosol contrasting with the distribution of @entity17892 at the apical membrane. The diagnostic procedure led to identifying two mutations of the @entity17893 gene. CONCLUSIONS: The functional loss of @entity17893 in DB/FOAR causes @entity4094 characterized by increased urinary shedding of @entity1400 and @entity17892 .
