- 期刊
Mitochondrial DNA Deletion Syndrome
粒線體DNA缺失症候群
摘要
因粒線體DNA缺失綜合症而引起的臨床表現變異很多。最常見的是 Kearns-Sayre症候群(KSS)，其在神經肌肉系統的症狀表現，輕微的僅見慢性的眼圈周圍肌肉麻痺(CPED, chronic Progressive external ophthalmoplegia)或粒線體性肌肉病變(MM, mitochondrial myopathy)。近年來，粒線體DNA缺失現象也見於嬰/幼兒，病狀的發作多涉及多重器官系統，而不像影響神經肌肉系統正常功能的KSS病人。分子研究資料顯示：最常見的5kb DNA(np8469-np13447)缺失現象通常見於KSS/MM/CPED病人。 一般來講，KSS病人的血液檢體檢查不出有缺失異常的粒線體DNA。帶罕見型粒線體DNA缺失異常的病人很可能在幼兒時期就出現不同類型的多重器官系統，但不涉及神經肌肉系統的臨床表現。造成多系統疾病的罕見型mtDNA缺失大多數存在於血液，肌肉和其他組織中。雖然對KSS/MM/CPED病人來說，侵入性肌肉切片診察(invasive muscle biopsy)是唯一可靠的分子診斷方法，但血液檢查依然可有效地供初步篩檢之用，特別是在病童或嬰兒表現不十分明確的多器官系統性疾病。
並列摘要
Clinical manifestation of mitochondrial DNA (mtDNA) deletion syndrome is heterogeneous. The most commonly observed is the neuromuscular presentation of Kearns Sayre syndrome (KSS). Mild form of mtDNA deletion may manifest with only chronic progressive external ophthalmoplegia (CPEO) or mitochondrial myopathy (MM). Recently, mtDNA deletion has been diagnosed in patients with infantile/early childhood onset of multisystemic disorders without neuromuscular involvement of KSS. Molecular studies have revealed that the most common 5 kb deletion (np8469-np13447) is mostly found in patients with KSS/MM/CPEO. Usually, the deleted mtDNAs are not present in the blood of KSS patients. Patients with rare type of deletions are more likely to have heterogeneous, multisystemic non-neuromuscular clinical presentations at young age. Most of the mutant mtDNAs with rare type of deletions are present in blood, muscle, and other tissues, resulting in multisystemic disorders. Although invasive muscle biopsy is the only approach to obtain a reliable molecular diagnosis in patients with KSS/MM/CPEO, a blood specimen can be used for initial diagnosis in patients who present with an undefined multisystemic disorder in early childhood or infancy.