建立日期 16895
主題： 第一型黏多醣症的診斷及治療
第一型黏多醣症（Mucopolysaccharidosis；MPS I）是一種體染色體隱性遺傳的代謝疾病，由於a-L-iduronidase(IDUA)基因缺陷，導致黏多醣無法分解而過量堆積，造成包括腦、骨骼肌肉系統、心臟、肺臟及眼睛等器官不可逆的傷害[1]，發生率約為十萬分之一[2]。根據發病的早晚及嚴重程度，第一型黏多醣症又可分為兩型，分別為早期發病、病情惡化嚴重、合併認知障礙的Hurler syndrome，若未經治療，病人通常十歲前即死亡；另一型則為發病較晚、主要影響中樞神經系統的attenuated MPS I，若未經治療，病人通常三十歲前死亡。目前已知有超過兩百個位於IDUA基因上的變異會造成MPS I，而罹病的小孩在出生時並無異樣，且黏多醣的堆積是個漸進的過程，出現的症狀及嚴重程度會因基因缺失的差異而有所不同，因而增加診斷上的難度。MPS I治療成功與否取決於早期正確的診斷及給予適當的治療計畫[3]。美國新生兒與兒童遺傳疾病諮詢委員及美國衛生管理當局已於2016年2月核准將MPS I納入新生兒的建議篩檢項目[4]。一旦新生兒的血液篩檢出現陽性，則需進一步對IDUA基因進行定序，以預測疾病的種類。若基因定序結果為Hurler syndrome型，則需轉介進行骨髓移植並評估其風險，若基因定序結果為attenuated MPSI則需給予酵素替代療法。倘若基因定序的結果仍無法預測疾病的種類，則需利用其他包括生理檢查、臨床評估、生化檢驗及核磁共振等來協助診斷。
References:
1. Muenzer, J., J.E. Wraith, and L.A. Clarke, Mucopolysaccharidosis I: management and treatment guidelines. Pediatrics, 2009. 123(1): p. 19-29.
2. Moore, D., et al., The prevalence of and survival in Mucopolysaccharidosis I: Hurler, Hurler-Scheie and Scheie syndromes in the UK. Orphanet J Rare Dis, 2008. 3: p. 24.
3. de Ru, M.H., et al., Enzyme replacement therapy and/or hematopoietic stem cell transplantation at diagnosis in patients with mucopolysaccharidosis type I: results of a European consensus procedure. Orphanet J Rare Dis, 2011. 6: p. 55.
4. US Department of Health and Human Services Health Resources and Services Administration. Nominate a condition. http://www.hrsa.gov/advisorycommittees/mchbadvisory/heritabledisorders/nominatecondition/reviews/nominatedconditions.pdf. . Accessed November 26, 2016.
References:
1. Muenzer, J., J.E. Wraith, and L.A. Clarke, Mucopolysaccharidosis I: management and treatment guidelines. Pediatrics, 2009. 123(1): p. 19-29.
2. Moore, D., et al., The prevalence of and survival in Mucopolysaccharidosis I: Hurler, Hurler-Scheie and Scheie syndromes in the UK. Orphanet J Rare Dis, 2008. 3: p. 24.
3. de Ru, M.H., et al., Enzyme replacement therapy and/or hematopoietic stem cell transplantation at diagnosis in patients with mucopolysaccharidosis type I: results of a European consensus procedure. Orphanet J Rare Dis, 2011. 6: p. 55.
4. US Department of Health and Human Services Health Resources and Services Administration. Nominate a condition. http://www.hrsa.gov/advisorycommittees/mchbadvisory/heritabledisorders/nominatecondition/reviews/nominatedconditions.pdf. . Accessed November 26, 2016.
