Haas R H, Light M, Rice M, Barshop B A
Department of Pediatrics, University of California San Diego, USA.
Neuropediatrics. 1995 Apr;26(2):90-4. doi: 10.1055/s-2007-979734.
The etiology of Rett syndrome (RS) remains a mystery. The clinical phenotype has similarities to that of patients with mitochondrial defects of oxidative metabolism. There is evidence of lactate and pyruvate elevations in blood and CSF in some patients. Over the last 10 years we have studied girls with RS looking for evidence of a defect in oxidative metabolism. We present data on lactate and pyruvate blood measurements in 30 patients with RS with repeated measurements performed over time in many. Taken as a whole the means of measurements of lactate and pyruvate fall within the control range, however, individual patients have marked elevation of both lactate and pyruvate with considerable fluctuation over time. Nine girls with typical RS were studied in detail using a clinical protocol designed to identify disorders of oxidative metabolism. These patients underwent fasting for 24 hours, glucose loading and alanine loading tests. Seven girls had skin and muscle biopsies performed. One patient admitted with particularly high blood lactate levels underwent hourly blood collections over a 24 hour period during which state of alertness was noted and respiratory monitoring was performed. In this patient serial blood sampling for lactate performed. In this patient serial blood sampling for lactate performed with oxypneumocardiogram recording demonstrated a fall in plasma lactate to normal levels during sleep when the respiratory pattern was normal. Such fluctuations of plasma lactate apparently correlated with sleep/wake state and respiration suggest that in some patients with RS lactate elevations may arise from respiratory abnormalities. Other positive findings included prediabetic glucose responses in three girls. Ammonia levels following alanine loading were normal in all patients.
瑞特综合征（RS）的病因仍是个谜。其临床表型与氧化代谢线粒体缺陷患者的表型相似。一些患者的血液和脑脊液中有乳酸和丙酮酸升高的证据。在过去10年里，我们对患有RS的女孩进行了研究，以寻找氧化代谢缺陷的证据。我们展示了30例RS患者的血液乳酸和丙酮酸测量数据，其中许多患者进行了多次重复测量。总体而言，乳酸和丙酮酸的测量均值在正常范围内，然而，个别患者的乳酸和丙酮酸均显著升高，且随时间有相当大的波动。我们使用旨在识别氧化代谢紊乱的临床方案，对9名典型RS女孩进行了详细研究。这些患者接受了24小时禁食、葡萄糖负荷试验和丙氨酸负荷试验。7名女孩进行了皮肤和肌肉活检。一名因血乳酸水平特别高入院的患者，在24小时内每小时采集一次血液，在此期间记录警觉状态并进行呼吸监测。对该患者进行了乳酸的系列血样采集。在该患者进行乳酸系列血样采集并记录血氧心音图时发现，当呼吸模式正常时，睡眠期间血浆乳酸水平降至正常。血浆乳酸的这种波动显然与睡眠/觉醒状态和呼吸有关，这表明在一些RS患者中，乳酸升高可能源于呼吸异常。其他阳性发现包括3名女孩有糖尿病前期的血糖反应。所有患者丙氨酸负荷后的氨水平均正常。
