Pertovaara M, Korpela M, Saarelainen S, Laitinen J, Järvenpää R, Laippala P, Lahdensuo A
Department of Internal Medicine, Tampere University Hospital, Finland.
Scand J Rheumatol. 2004;33(5):343-8. doi: 10.1080/03009740410006196.
In a previous study pulmonary hyperinflation was observed frequently in patients with primary Sjogren's syndrome (pSS) and elevated serum beta-2 microglobulin (beta2m) concentrations were associated with hyperinflation.
To evaluate the significance of baseline serum beta2m concentration and to identify other possible risk factors for pulmonary involvement in long-term follow-up of patients with pSS.
Nineteen pSS patients whose pulmonary function tests (PFTs) had been previously studied were reexamined after a median follow-up of 10 years. Pulmonary symptoms were recorded, chest radiograph, and high-resolution computed tomography (HRCT) were evaluated and methacholine provocation and PFTs including flow-volume spirometry, body plethysmography, and diffusing capacity performed.
Baseline serum beta2m concentrations correlated inversely with follow-up total lung capacity (TLC), vital capacity (VC), and diffusing capacity (DL), and positively with residual volume (RV), all expressed as percentage of predicted values. Diminished airways resistance (Raw) and, correspondingly, elevated specific conductance (SGaw) were frequent findings in pSS patients at follow-up, indirectly implying stiffness of the lungs and a restrictive decrease in lung volumes. Baseline serum protein concentration was higher and IgG concentration tended to be higher in pSS patients who at follow-up had elevated SGaw compared with others. Interstitial changes in HRCT were found more frequently in patients with elevated SGaw than in those without.
Our results suggest that subtle restrictive changes in pulmonary function are more prone to develop in the long term in pSS patients with elevated serum beta2m concentration and other signs of immunological activity at baseline.
在之前的一项研究中，原发性干燥综合征（pSS）患者中经常观察到肺过度充气，血清β2微球蛋白（β2m）浓度升高与肺过度充气相关。
评估基线血清β2m浓度的意义，并确定pSS患者长期随访中肺部受累的其他可能危险因素。
对19例之前进行过肺功能测试（PFTs）的pSS患者进行了复查，中位随访时间为10年。记录肺部症状，评估胸部X线片和高分辨率计算机断层扫描（HRCT），并进行乙酰甲胆碱激发试验以及包括流量-容积肺活量测定、体容积描记法和弥散功能在内的PFTs。
基线血清β2m浓度与随访时的肺总量（TLC）、肺活量（VC）和弥散功能（DL）呈负相关，与残气量（RV）呈正相关，所有指标均以预测值的百分比表示。随访时，pSS患者经常出现气道阻力（Raw）降低以及相应的比传导率（SGaw）升高，这间接提示肺的僵硬和肺容积的限制性减少。与其他患者相比，随访时SGaw升高的pSS患者基线血清蛋白浓度更高，IgG浓度也有升高趋势。HRCT上的间质改变在SGaw升高的患者中比未升高的患者中更常见。
我们的结果表明，基线血清β2m浓度升高且有其他免疫活动迹象的pSS患者，长期更容易出现细微的限制性肺功能改变。
