Woman with Fabry has 2 disorders affecting her heart, kidneys
Report from China is likely first to document rare triple combination
A woman with Fabry disease was found to have two co-occurring disorders — a heart condition called dilated cardiomyopathy (DCM) and an autoimmune kidney disorder called immunoglobulin A nephropathy (IgAN) — a rare combination.
“To the best of our knowledge, this is the first report on such a case,” researchers wrote in a study, “Concurrent fabry disease and immunoglobulin a nephropathy: a case report,” published in BMC Nephrology.
Fabry disease is a genetic disorder caused by mutations in the GLA gene, which results in the toxic buildup of certain fatty molecules, called Gb3 and Lyso-Gl3, in organs, usually the kidneys. The kidneys are also the main site of damage in IgAN, an immune disorder characterized by certain types of antibodies (immunoglobulin A or IgA) that build up in the kidneys.
DCM is a condition in which the left ventricle — the part of the heart responsible for pumping oxygen-rich blood out to the body — becomes enlarged. Mutations in certain genes, including the TTN and BAG3 genes, can set the stage for DCM to develop.
Fabry-IgAN combination seen in China, Japan
Scientists in China described the case of a 60-year-old woman with all three conditions. The woman, who had a history of left ventricle enlargement, sought medical attention for swelling in her face and legs, and chest tightness when walking.
Doctors ran a battery of laboratory tests, including a kidney biopsy that showed signs of damage consistent with both Fabry disease and IgAN.
While it’s rare for Fabry and IgAN to develop concurrently in the same person, it has happened before, the researchers wrote. Most reports of concurrent Fabry and IgAN have been from China or Japan, which have comparatively high rates of IgAN.
Genetic testing revealed the woman had a Fabry-causing mutation in the GLA gene and DCM-associated mutations in both the TTN and BAG3 genes. Her 35-year-old son was found to carry the same Fabry-causing GLA mutation.
“To the best of our knowledge, this is the first report of concurrent [Fabry disease] and IgAN with these mutations in TTN and BAG3 genes in a patient with [an enlarged left ventricle],” the researchers wrote.
The patient was treated with losartan, a blood pressure medication. She refused enzyme replacement therapy for Fabry disease, citing financial constraints. Her heart and kidney function remained stable over the course of follow-up.
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