Additionally, Bansal et al. described a patient with tumor-induced osteomalacia and elevations in serum concentrations of both FGF7 and FGF23.[11] Interestingly, a recent study showed that low serum FGF7 concentrations were observed in pediatric patients with hypophosphatasia and hyperphosphatemia.[12] Moreover, the intravenous FGF7 administration increased the fractional excretion of phosphate in vivo in rats, suggesting that hyperphosphatemia in pediatric hypophosphatasia might be partly attributable to FGF7 insufficiency. This evidence concerns the gene FGF23 and hypophosphatasia.