Fabry disease in the era of enzyme replacement therapy: a renal perspective

Fabry disease, the second most prevalent lysosomal storage disorder after Gaucher disease, is caused by mutations of the gene encoding the lysosomal hydrolase, alpha-galactosidase A. The enzymatic defect is inherited in an X-linked recessive fashion and leads to systemic glycosphingolipid deposition, resulting in profound dysfunction of neurological, renal, cardiac, and cerebrovascular systems. Although symptoms typically appear in childhood in hemizygous males and some heterozygous females, the diagnosis is often delayed or unrecognized, owing to variable presentations and low incidence. The initial phase begins in childhood or adolescence and is characterized by neuropathic pain, angiokeratomas, and ocular deposits. The later phase is distinguished by progressive cardiac, cerebral, and renal involvement, leading to multi-organ dysfunction and death. Recently published clinical trials have demonstrated the efficacy of enzyme replacement therapy in decreasing neuropathic pain and substrate deposition in target organs. Pediatricians have a key role to play in making the diagnosis, so that therapy can be initiated before irreversible tissue injury develops. Further research is required to determine optimal dosing protocols for treatment and to establish whether therapy can retard the progression of organ dysfunction, or even prevent these complications altogether.