Uzun K, Vural H, Ozer F, Imecik O
Department of Chest Diseases, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey.
Clin Chem Lab Med. 2000 Jul;38(7):661-5. doi: 10.1515/CCLM.2000.095.
Uric acid is known to be an end product of purine metabolism. Increases in uric acid may be found in clinical conditions associated with tissue hypoxia. We have investigated the value of uric acid to differentiate between a transudate and exudate. In this study, we measured uric acid in the pleural fluid and the serum of 110 patients, 30 women and 80 men with a mean age of 49.5+/-19 years. Light's criteria were used to differentiate between a transudate and exudate. Mean serum uric acid was 496.7+/-153.4 micromol/l in patients with transudates and 291.3+/-143.1 micromol/l in patients with exudates. Mean pleural fluid uric acid was 487.7+/-165 micromol/l in patients with transudates and 279.9+/-142.1 micromol/l in patients with exudates. These data showed that the levels of serum and pleural uric acid were higher in transudates than exudates (p<0.01). However, there was no significant difference between pleural fluid/serum uric acid ratio of the two patient groups (p>0.05). The specificity and sensitivity of pleural uric acid for diagnosis of transudate effusions were 73% and 80.6%, respectively. The specificity and sensitivity of pleural uric acid for diagnosis of transudate effusions from exudates without malignancy were 71.8% and 91.7%, respectively. The sensitivity and specificity of pleural lactate dehydrogenase for diagnosis of exudates were 82% and 89%; the sensitivity and specificity of pleural fluid/serum lactate dehydrogenase were 85% and 89%; the sensitivity and specificity of pleural fluid/serum protein were 91% and 89%, respectively. Using all three of Light's criteria together, the sensitivity was 91% and its specificity was 94%. Our findings indicate that determination of uric acid in pleural fluid may be of diagnostic value in differential diagnosis of transudates and exudates. The sensitivity of pleural uric acid measurement was higher for exudates without malignancy. However, Light's criteria remain the best means of separating transudates from exudates.
已知尿酸是嘌呤代谢的终产物。在与组织缺氧相关的临床病症中可能会出现尿酸升高的情况。我们研究了尿酸在鉴别漏出液和渗出液方面的价值。在本研究中，我们测量了110例患者（30名女性和80名男性，平均年龄49.5±19岁）胸腔积液和血清中的尿酸。采用Light标准来鉴别漏出液和渗出液。漏出液患者的平均血清尿酸为496.7±153.4微摩尔/升，渗出液患者的平均血清尿酸为291.3±143.1微摩尔/升。漏出液患者的平均胸腔积液尿酸为487.7±165微摩尔/升，渗出液患者的平均胸腔积液尿酸为279.9±142.1微摩尔/升。这些数据表明，漏出液中血清和胸腔尿酸水平高于渗出液（p<0.01）。然而，两组患者的胸腔积液/血清尿酸比值之间无显著差异（p>0.05）。胸腔尿酸诊断漏出液的特异性和敏感性分别为73%和80.6%。胸腔尿酸诊断无恶性肿瘤渗出液中漏出液的特异性和敏感性分别为71.8%和91.7%。胸腔乳酸脱氢酶诊断渗出液的敏感性和特异性分别为82%和89%；胸腔积液/血清乳酸脱氢酶的敏感性和特异性分别为85%和89%；胸腔积液/血清蛋白的敏感性和特异性分别为91%和89%。同时使用Light的所有三项标准，敏感性为91%，特异性为94%。我们的研究结果表明，测定胸腔积液中的尿酸在鉴别漏出液和渗出液的诊断中可能具有价值。胸腔尿酸测量对无恶性肿瘤的渗出液敏感性更高。然而，Light标准仍然是区分漏出液和渗出液的最佳方法。
