Fottner Andreas, Birkenmaier Christof, von Schulze Pellengahr Christoph, Wegener Bernd, Jansson Volkmar
Department of Orthopaedic Surgery, Grosshadern Medical Center, University of Munich, Munich, Germany.
Arthroscopy. 2008 Feb;24(2):229-33. doi: 10.1016/j.arthro.2007.07.029. Epub 2007 Nov 5.
The aim of this study was to evaluate the usefulness of serum procalcitonin (PCT) to differentiate between septic and nonseptic acute arthritis.
Thirty-three patients who presented to our outpatient clinics with the symptoms of acute arthritis of unknown origin were enrolled in this study. We determined the serum concentrations of PCT and C-reactive protein and performed a white blood cell count. The definitive diagnosis was determined by microbiologic examination of a joint aspirate.
Microbiologic cultures showed that 15 patients had septic arthritis. In these patients the PCT levels were significantly increased compared with those in the 18 patients with nonseptic arthritis (mean +/- SD, 1.18 +/- 1.66 ng/mL v 0.078 +/- 0.073 ng/mL; P = .001). On the basis of the normal range (<0.5 ng/mL), the test sensitivity in our series was 53.3% with a specificity of 100%. C-reactive protein levels in patients with septic arthritis were also significantly elevated compared with the nonseptic group. Because in either group no value was within the normal range (<0.5 mg/dL), the specificity was 0%.
In this study serum PCT levels of patients with septic arthritis were significantly higher than those of patients with nonseptic arthritis (P = .001). However, the sensitivity when referencing the normal upper limit of PCT (0.5 ng/mL) is not high enough to establish a diagnosis based exclusively on serum parameters. This reflects the results of other studies examining localized infections without generalized bacteremia. The data suggest that a specific PCT cutoff level for localized infections could be helpful in the future.
Level III, diagnostic study of nonconsecutive patients without consistently applied reference gold standard.
本研究旨在评估血清降钙素原（PCT）在鉴别感染性和非感染性急性关节炎方面的效用。
33例因不明原因急性关节炎症状前来我院门诊就诊的患者纳入本研究。我们测定了血清PCT和C反应蛋白浓度，并进行了白细胞计数。通过关节穿刺液的微生物学检查确定最终诊断。
微生物培养显示15例患者患有感染性关节炎。这些患者的PCT水平与18例非感染性关节炎患者相比显著升高（均值±标准差，1.18±1.66 ng/mL对0.078±0.073 ng/mL；P = 0.001）。以正常范围（<0.5 ng/mL）为基础，我们系列研究中的检测敏感性为53.3%，特异性为100%。感染性关节炎患者的C反应蛋白水平与非感染性组相比也显著升高。由于两组中均无值处于正常范围内（<0.5 mg/dL），特异性为0%。
在本研究中，感染性关节炎患者的血清PCT水平显著高于非感染性关节炎患者（P = 0.001）。然而，以PCT正常上限（0.5 ng/mL）为参考时，敏感性不足以仅基于血清参数进行诊断。这反映了其他关于无全身性菌血症的局部感染研究的结果。数据表明，针对局部感染的特定PCT临界值未来可能会有所帮助。
III级，对非连续患者的诊断性研究，未始终应用参考金标准。
