講演情報
[P23-4]新生児スクリーニングを契機に見つかったファブリー病の一家系
○入月 浩美1,2, 澤野 堅太郎1, 柴田 奈央1, 長崎 啓祐1 (1.新潟大学医歯学総合病院 小児科, 2.新潟大学医歯学総合病院 ゲノム医療部 遺伝医療センター)
[Background] Fabry disease is an X-linked inherited disorder of inborn errors of metabolism caused by a deficiency of the lysosomal enzyme α-galactosidase. The disease presents with various symptoms, including pain in the extremities, sweating abnormalities, angiokeratomas, progressive renal failure, cardiac disease, and cerebrovascular disease, but the clinical diversity makes diagnosis difficult, and many cases lead to irreversible organ damage. We report a family of Fabry disease found through newborn screening. [Case] The proband was born to non-consanguineous healthy parents at 38 weeks of gestation. In the newborn screening test, the α-galactosidase activity in dried blood spots was low as 0.53 μmol/h (cut-off: 3.0), suggesting Fabry disease. His leukocyte enzyme activity was low at 2.9 nmol/ml Protein/h and blood Lyso-Gb3 was 2.28 ng/ml. Genetic testing revealed a hemizygous GLA pathogenic variant of c.1088G＞A, p.R363H. Molecular genetic testing for at-risk relatives in this family member through genetic counseling revealed the same variant in his mother and maternal grandfather, who were unaware of the disease. In addition, the grandfather was found to have chronic kidney disease with mulberry bodies, indicating the appearance of organ damage due to Fabry disease. The mother and the proband have no symptoms at this time and are being carefully followed up. [Discussion] There are effective treatments for Fabry disease and early diagnosis is very important. Our case demonstrated that newborn screening is useful in detecting undiagnosed affected individuals.