Familial renal hypophosphatemia, minor facial anomalies, intracerebral calcifications, and non-rachitic bone changes: apparently new syndrome?

We report on two brothers with renal hypophosphatemia, intracerebral calcifications, minor facial anomalies, and short distal phalanges. The children presented with recurrent dental abscesses; one had premature closure of the anterior fontanelle. Biochemical findings included hypophosphatemia and elevated serum alkaline phosphatase with normocalcemia. Blood levels of parathyroid hormone, 1,25(OH)2 and 25(OH) vitamin D levels were normal; TRP (the fractional tubular reabsorption of PO4) and TmP/GFR (the tubular maximum rate of PO4 reabsorption in relation to GFR) were low. Both parents had a normal serum phosphate and brain CT scan without evidence of calcifications. This apparently new syndrome of renal hypophosphatemia associated with intracerebral calcifications appears to be inherited as either an autosomal recessive or an X-linked trait.