The importance of medical interview with CKD patient in diagnoses of a family with Fabry disease

A 47-year-old Japanese man was admitted to our hospital for evaluation of proteinuria, which was detected when he was 37 years of age. His creatinine clearance levels had fallen to 76.3 mL/min/1.73 m2. A kidney biopsy was conducted, and the patient’s low plasma α-galactosidase A levels suggested Fabry disease. After genetic counseling, GLA analysis revealed a novel mutation p.L387P. Interview with the patient revealed that both his younger brother and mother suffered from cardiomyopathy and were undergoing cardiological treatment. They also were positive for proteinuria. About 30 years ago, the patient’s cousin (aged 25) was diagnosed with Fabry disease. He underwent hemodialysis for 9 years until his death at 42. At that time, the patient and his brother had not been investigated for Fabry disease so their cousin could not act as a proband for the brothers. Eventually, the patient, his mother, and his brother were put on enzyme replacement therapy with agalsidase beta. As this series of cases shows, medical interviews to collate both medical and family history were essential for the discovery of Fabry disease in these patients. In addition, being a treatable genetic disorder, Fabry disease should be listed in the standard differential diagnoses of systemic and familial diseases, including unknown cause of nephropathy or cardiomyopathy, for early detection of the disorder.