Leigh 증후군 환자의 임상적 생화학적 진단

Abstract

Purpose: Deficits of the respiratory chain are reported to be the major cause of Leigh syndrome is said to be the underlying causes. The need for biochemical diagnosis to draw more accurate diagnosis or prognosis to support treatments is rapidly increasing. This study tried to analyze the aspects of clinical characteristics and biochemical diagnosis of mitochondrial respiratory chain complex (MRC) defect in Leigh syndrome, using methods of biochemical enzyme assay. Methods: We included total number of 47 patients who satisfied the clinical criteria of Leigh syndrome and confirmed by biochemical diagnosis. All those patients went through muscle biopsy to perform biochemical enzyme assay to analyze MRC enzyme in order to find the underlying cause of Leigh syndrome. Results: MRC I defect was seen in 23 (48.9%) cases taking the first place and MRC IV defect in 15 (31.9%) following it. There were 9 (19.2%) cases of combined MRC defect. Combined cases of type I and IV were detected in 7 (14.9%) patients while type I and V in 2 (4.3%). The onset age of symptom was less than 1 year old in 28 (59.6%). The most common early symptom, observed in 23 (48.9%), was delayed development, but there were other various neurological symptoms observed as well. In regard with the disease progression, 35 (74.5%) patients showed slowly progressive course, the one that progressed continuously but slowly over 2 years of period. As for Maximum motor development, 22 (46.8%) were bed-ridden state, most of them suffering serious delayed development. Patients showed various symptoms with different organs involved, though neuromuscular involvement was most prominent. Delayed development was seen in all cases. Multifocal lesion in brain MRI study was seen in 36 (76.6 %) cases, taking a greater percentage than 11 (23.4%) cases with single lesion. In MR spectroscopy study, the characteristic lactate peak of mitochondrial disease was identified in 20 (42.6%) patients. Conclusions: Further analysis of clinical and biochemical diagnosis on more extended group of patients with Leigh syndrome will enable us to improve diagnostic precision and to understand the natural course of mitochondrial disease.