Lieberman J, Bell D S
Department of Medicine, Veterans Affairs Medical Center/UCLA, Sepulveda 91343.
Am J Med. 1993 Oct;95(4):407-12. doi: 10.1016/0002-9343(93)90310-l.
To study the reliability of a serum angiotensin-converting enzyme (ACE) assay as a marker for the chronic fatigue-immune dysfunction syndrome (CFIDS), and to compare some enzyme characteristics of ACE in CFIDS with that in sarcoidosis.
Forty-nine patients with CFIDS and 56 endemic control subjects from Lyndonville, New York, and Charlotte, North Carolina; plus 23 untreated patients with active sarcoidosis, 24 with sarcoidosis receiving corticosteroid therapy, and 32 patient controls without sarcoidosis from California. Serum ACE levels were determined with a spectrophotometric method. The effect of freezing and thawing and the effect of storage at 4 degrees C were compared between CFIDS and sarcoidosis samples.
Serum ACE levels were elevated in 80% of patients with CFIDS and 30% of endemic control subjects as compared with 9.4% of nonendemic California control subjects. The ACE activity in CFIDS differed from that in sarcoidosis because of its lability with storage at 4 degrees C in CFIDS and its partial activation with freezing and thawing. Thus, ACE activity was elevated in the majority of CFIDS patients either upon initial assay or upon a subsequent assay after refreezing. ACE activity was elevated in 87% of patients with active sarcoidosis and was not affected by storage or freezing and thawing.
Serum ACE elevations may be a useful marker for CFIDS, especially if a method can be developed to distinguish ACE in CFIDS from that in sarcoidosis. The sensitivity for CFIDS was 80%, with 68% specificity in an endemic area. The increased prevalence of serum ACE elevations in endemic controls as compared with nonendemic controls suggests that an ACE increase may be an early manifestation of CFIDS and supports the concept that CFIDS is a definite disease state.
研究血清血管紧张素转换酶（ACE）检测作为慢性疲劳-免疫功能紊乱综合征（CFIDS）标志物的可靠性，并比较CFIDS患者与结节病患者体内ACE的某些酶学特性。
49例CFIDS患者以及来自纽约州林登维尔和北卡罗来纳州夏洛特的56名当地对照者；另外还有23例未经治疗的活动性结节病患者、24例接受皮质类固醇治疗的结节病患者以及32名来自加利福尼亚州的无结节病的患者对照。采用分光光度法测定血清ACE水平。比较CFIDS和结节病样本冻融及4℃保存的影响。
与9.4%的非当地加利福尼亚对照者相比，80%的CFIDS患者和30%的当地对照者血清ACE水平升高。CFIDS患者体内的ACE活性与结节病患者不同，因为它在CFIDS患者体内4℃保存时不稳定，且冻融后会部分激活。因此，大多数CFIDS患者在初次检测时或再次冻融后的后续检测中ACE活性都会升高。87%的活动性结节病患者ACE活性升高，且不受保存或冻融的影响。
血清ACE升高可能是CFIDS的一个有用标志物，尤其是如果能开发出一种方法来区分CFIDS患者与结节病患者体内的ACE。CFIDS的敏感性为80%，在流行地区特异性为68%。与非流行地区对照相比，流行地区对照者血清ACE升高的患病率增加，这表明ACE升高可能是CFIDS的早期表现，并支持CFIDS是一种明确疾病状态的概念。
