Go Tsukuya

The elevation of serum napsin A in idiopathic pulmonary fibrosis, compared with KL-6, surfactant protein-A and surfactant protein-D

BackgroundNapsin A, an aspartic protease, is mainly expressed in alveolar type-II cells and renal proximal tubules and is a putative immunohistochemical marker for pulmonary adenocarcinomas. This study sought to determine whether napsin A could be measured in the serum to evaluate its relationship to idiopathic pulmonary fibrosis (IPF) and determine whether renal dysfunction might affect serum napsin A levels.MethodsSerum levels of napsin A were measured in 20 patients with IPF, 34 patients with lung primary adenocarcinoma, 12 patients with kidney diseases, and 20 healthy volunteers. Surfactant protein (SP)-A, SP-D, and Krebs von den Lungen-6 (KL-6) levels in serum and pulmonary function tests were also evaluated in IPF patients.ResultsCirculating levels of napsin A were increased in patients with IPF, as compared with healthy controls, and they correlated with the severity of disease. Moreover, the serum napsin A levels were not elevated in patients with pulmonary adenocarcinoma or renal dysfunction. The distinguishing point between IPF and the controls was that the area under the receiver operating characteristic curve (ROC) of napsin A was larger than that of KL-6, SP-A, or SP-D.ConclusionThese findings suggest that serum napsin A may be a candidate biomarker for IPF.

Comparison of the COPD Population Screener and International Primary Care Airway Group questionnaires in a general Japanese population: the Hisayama study.

Background The incidence of chronic obstructive pulmonary disease (COPD) is increasing worldwide. In Japan and other countries, epidemiological studies have found that many patients with COPD are underdiagnosed and untreated, and thus, early detection and treatment of COPD has been emphasized. Screening questionnaires may have utility in the initial detection of COPD. Objective This study aimed to validate and compare the COPD Population Screener (COPD-PS) and the International Primary Care Airway Group (IPAG) questionnaires in a general Japanese population. Patients and methods Eligible subjects 40 years of age and older living in the town of Hisayama were solicited to participate in a health checkup in 2012. All subjects 40–79 years of age without physician-diagnosed asthma or lung resection were recruited, and 2,336 subjects who fully completed both questionnaires and who had valid spirometry measurements were analyzed. Persistent airflow obstruction (AO) was defined by a postbronchodilator forced expiratory volume in 1 second/forced vital capacity <0.70. Receiver operating characteristic curves, net reclassification improvement, and integrated discrimination improvement were used to examine the ability of the COPD-PS and IPAG questionnaires to discriminate between subjects with and without AO. Results The overall area under the receiver operating characteristic curve for the COPD-PS questionnaire was 0.747 (95% confidence interval [CI], 0.707–0.788) and for the IPAG was 0.775 (95% CI, 0.735–0.816), with no significant difference (P=0.09). The net reclassification improvement and integrated discrimination improvement were −0.107 (95% CI, −0.273–0.058; P=0.203) and −0.014 (95% CI, −0.033–0.006; P=0.182), respectively. Conclusion The five-item COPD-PS questionnaire was comparable to the eight-item IPAG for discriminating between subjects with and without AO. The COPD-PS is a simple and useful screening questionnaire for persistent AO.

Serum B cell–activating factor (BAFF) level in connective tissue disease associated interstitial lung disease

BackgroundInterstitial lung diseases (ILDs) are common in patients with connective tissue diseases (CTDs). Although the diagnosis of an underlying CTD in ILD (CTD-ILD) affects both prognosis and treatment, it is sometimes difficult to distinguish CTD-ILD from chronic fibrosing interstitial pneumonia (CFIP). B cell–activating factor belonging to the tumour necrosis factor family (BAFF) plays a crucial role in B cell development, survival, and antibody production.MethodsWe examined serum levels of BAFF, surfactant protein D (SP-D), and Krebs von den Lungen-6 (KL-6) in 33 patients with CTD-ILD, 16 patients with undifferentiated CTD-ILD, 19 patients with CFIP, and 26 healthy volunteers. And we analysed the relationship between serum BAFF levels and pulmonary function, as well as the expression of BAFF in the lung tissue of patients with CTD-ILD.ResultsSerum levels of BAFF were significantly higher in CTD-ILD patients compared to healthy subjects and CFIP patients. However, there were no significant differences in serum levels of SP-D and KL-6. Furthermore, serum BAFF levels in CTD-ILD patients were inversely correlated with pulmonary function. BAFF was strongly expressed in the lungs of CTD-ILD patients, but weakly in normal lungs.DiscussionThis is the first study to demonstrate that serum BAFF levels were significantly higher in CTD-ILD patients compared to healthy subjects and CFIP patients. Furthermore, serum BAFF levels were correlated with pulmonary function. We consider that serum BAFF levels in patients with CTD-ILD reflect the presence of ILDs disease activity and severity.ConclusionThese finding suggest that BAFF may be a useful marker for distinguishing CTD-ILD from CFIP.

Development of a self-scored persistent airflow obstruction screening questionnaire in a general Japanese population: The Hisayama study

Background The use of a simple screening questionnaire to detect persistent airflow obstruction (AO) in COPD may facilitate the early, accurate diagnosis of COPD in general practice settings. Objective This study developed an original persistent AO questionnaire for screening individuals with COPD in a general Japanese population. Methods A working group was established to generate initial draft questionnaire items about COPD. Eligible subjects aged 40 and older living in Japan were solicited to participate in a health checkup from 2014 to 2015. In study I, 2,338 subjects who fully completed the initial draft questionnaire and who had valid spirometry measurements were statistically analyzed to determine the final questionnaire items as a COPD screening questionnaire (COPD-Q). Persistent AO was defined as a post-bronchodilator FEV1/FVC <0.70. In study II, the working group analyzed the weighted scores for individual items and established a cutoff point for the COPD-Q based on the data of 2,066 subjects in the Hisayama study. Receiver operating characteristic (ROC) curves were used to examine the ability of the COPD-Q to discriminate between subjects with and without AO. Results The five-item COPD-Q was established based on 19 initial draft items in study I and the weighted scores of individual items. The overall area under the ROC curve for the COPD-Q was 0.796 (95% confidence interval, 0.707–0.788). A cutoff of 4 points resulted in a sensitivity of 71.0% and a specificity of 70.1%. The positive predictive value was 10.8%, and the negative predictive value was 97.9%. The crude odds ratio of the COPD-Q for AO was 5.8. Conclusion The five-item COPD-Q is a useful questionnaire for diagnosing persistent AO in a general Japanese population and is expected to be an effective first-stage screening tool for detecting COPD.