14例多发性肌炎／皮肌炎的肺间质病变误诊分析

目的：提高对多发性肌炎／皮肌炎（PM／DM）,合并肺间质病变（ILD）的认识。方法：对14例PM／DM合并ILD进行回顾性临床分析。结果：14例中男女之比为8：6，平均年龄43．7岁，平均误诊时间6．2个月，误诊为呼吸系统疾病22例次，误诊为感染性疾病21例次。结论：误诊原因：年龄及性别反差；ILD症状在前为主掩盖了PM／DM；检查手段特异性和敏感性差。电视引导下经胸腔镜（VATS）活检，可提高PM／DM并ILD诊断的准确性。     

多发性肌炎/皮肌炎合并肺间质病变的临床特征和预后

目的 研究多发性肌炎(PM)和皮肌炎(DM)合并肺间质病变(ILD)的临床特点和预后.方法 回顾性分析107例PM/DM患者的临床资料,包括首发症状、临床表现、实验室检查、影像学资料、治疗及预后.结果 107例PM/DM患者合并ILD有28例,ILD发生率为26.2%.①合并ILD的首发症状为关节炎或关节痛者高于无ILD(P<0.05);合并ILD临床表现为关节炎或关节痛、发热、干咳气促者明显高于无ILD(P<0.05).②DM合并ILD患者大多有特异性皮疹,呼吸困难较重(P<0.05),而PM合并ILD患者肌痛、肌无力较重(P<0.05).③合并ILD的红细胞沉降率(ESR)和C反应蛋白(CRP)明显高于无ILD(P<0.05);DM-ILD组肌酶谱以羟丁酸脱氢酶(HBDH)、天冬氨酸转氨酶(AST)升高为主(P≤0.05),PM合并ILD患者肌酶谱以肌酸激酶(CK)和肌酸激酶同工酶(CK-MB)为主(P<0.05).④合并ILD的28例PM/DM患者经治疗,20例病情改善,8例重症7例均为DM合并ILD,5例治疗无效因Ⅰ型呼吸衰竭死亡(病死率占PM/DM合并ILD患者的17.9%).结论 ①首发症状为关节炎或关节痛,临床表现有关节炎或者关节痛、发热以及ESR和CRP高者易合并ILD;有特异性皮疹、AST升高的DM易合并ILD;肌酶以CK和CK-MB升高为主的PM易合并ILD.②DM合并ILD病情进展凶险,病死率高,预后不良.     

血清KL-6检测在特发性炎性肌病伴肺间质病变诊断中的价值

目的探讨血清KL-6检测在特发性炎性肌病(IIM)合并肺间质病变(ILD)诊断中的作用。方法多发性肌炎(PM)和皮肌炎(DM)患者53例,其中合并有ILD的22例,正常对照者50名及肺部感染患者22例。酶联免疫吸附试验(ELISA)检测血清KL-6浓度。分析PM/DM患者临床表现及预后与血清KL-6水平的相关性。结果血清KL-6浓度在合并ILD的PM/DM组、未合并ILD的PM/DM组、肺部感染组和正常对照组的平均值分别是(1543±761)、(429±106)、(336±196)和(289±105)U/ml。合并ILD的PM/DM组血清KL-6水平较未合并ILD的PM/DM组、肺部感染组和正常对照组均显著升高(P＜0．01)。而未合并ILD的PM/DM组、肺部感染组和正常对照组间差异无统计学意义(P＞0．05)。血清KL-6的升高与肺间质病变呈显著正相关(P＜0．01),KL-6诊断PM/DM合并ILD的敏感性为90．9%,特异性为80．6%。随访分析表明,6例死亡的PM/DM患者血清KL-6水平明显高于其他伴发ILD的PM/DM患者(P＜0．01)。结论血清KL-6浓度是PM/DM合并ILD特异和敏感的血清学指标,它可用来鉴别肺部感染和肺间质病变。高水平的血清KL-6浓度可能提示预后差。     

皮肌炎/多发性肌炎肺间质病变的临床及相关因素分析

皮肌炎(dermatomyositis，DM)和多发性肌炎(polymyositis．PM)是一种以侵犯骨骼肌为主的全身性疾病，部分伴有全身器官受累。肺间质病变(interstitial lung disease，ILD)是其常见且严重的并发症，治疗效果欠佳,病死率高。为提高临床医生对DM／PM合并ILD的认识,我们回顾性分析了80例DM／PM的临床资料,探讨DM／PM合并ILD的相关因素，现报告如下。     

非酒精性脂肪性肝病合并2型糖尿病患者血清铁蛋白变化及其临床意义

目的 探讨非酒精性脂肪性肝病(NAFLD)合并2型糖尿病(T2DM)患者血清铁蛋白(SF)的变化及其临床意义。方法 本文纳入633例NAFLD合并T2DM、163例T2DM和163例NAFLD患者,检测血清SF和其他血清指标,应用二分类Logistic多元回归分析。结果 NAFLD合并T2DM患者血清SF水平为(293.5±206.4)ng/ml,显著高于T2DM组[(122.1±108.8)ng/ml,P<0.01]或NAFLD组[(202.5±127.6)ng/ml,P<0.01];血清尿酸(UA)水平为(401.2±91.5)μmol/l,显著高于T2DM组[(345.7±88.227)μmol/l,P<0.01];血清C反应蛋白(CRP)水平为(2.4±1.9)mg/dl,显著高于T2DM组[(1.3±1.7)mg/dl,P<0.01]或NAFLD组[(1.6±1.4)mg/dl,P<0.01];二分类Logistic多元回归分析显示SF和UA是NAFLD合并T2DM的独立预测因素(P＜0.05)。结论 检测血清铁可以预测NAFLD患者合并2型糖尿病,应该及时进行相关检查,以早期发现和处理。     

多发性肌炎/皮肌炎合并间质性肺疾病的相关因素及预后不良因素分析

目的 探讨多发性肌炎/皮肌炎(PM/DM)患者发生间质性肺疾病(ILD)的相关因素及影响预后的不良因素.方法 以上海第二军医大学长海医院1997年1月至2006年11月收住的PM/DM患者87例为研究对象,分为ILD组40例(男13例,女27例),平均年龄(54±13)岁;非ILD组47例(男25例,女22例),平均年龄(45±18)岁.对ILD的发生率、临床特征和预后进行分析.正态分布的计量资料采用t检验,偏态分布的计量资料采用秩和检验,计数资料两组率的比较采用x2检验,PM/DM伴发ILD的预测因素和预后不良因素采用logistic回归分析和Kaplan-Meier生存曲线.结果 PM/DM中ILD的发生率为46％(40/87),病死率为40％(16/40).ILD组的平均年龄[(54±13)岁]明显大于非ILD组[(45±18)岁];ILD组出现发热(21/40)、吞咽困难(16/40)、关节痛(26/40)、Gottron皮疹(14/40)和心脏损害(26/40)的百分率明显高于非ILD组(分别为7/47、8/47、9/47、2/47和14/47);ILD组的血清乳酸脱氢酶[(472±285)IU]和ESR[(44 ±24)mm/1 h]明显高于非ILD)组[(310±238)IU和(26±24)mm/1 h];ILD组的IgG[(18±9)g/L]明显高于非ILD组[(14±5)g/L].经多因素非条件logistic回归分析,筛选出4个与ILD相关的预测因子:Gottron皮疹、关节痛、发热和年龄≥40岁,其相对危险度分别为12.048、7.812、6.329和5.236;生存分析结果显示,Gottron皮疹、心脏损害和肺间质病变是影响ILD预后的不良因素.结论 PM/DM患者年龄≥40岁,出现Gottron皮疹、关节痛和发热与ILD的发生密切相关,Gottron皮疹、心脏损害和肺间质病变是影响ILD预后的不良因素.     

以急进性肺间质病变为突出表现的无肌炎的皮肌炎

目的了解以急进性肺间质病变为突出表现的临床无肌炎的皮肌炎的临床特点转归和治疗。方法回顾分析本院1998—2005年住院的成人特发性皮肌炎/多发性肌炎(DM/PM)202例,按临床无肌炎的皮肌炎(CADM)、典型DM、PM进行分组,有无合并临床肺间质病变(ILD)进行分层。对随访的145例DM/PM行生存分析和COX回归,分析预后和危险因素。横断面研究用Logistic回归分析ILD相关的预测因子。结果①存在临床ILD是DM/PM预后的最重要危险因素,OR为4．826(95%CI为1．60～14．56．P=0．005)；而亚临床ILD与无ILD的DM/PM生存曲线差异无统计学意义。②CADM、典型DM、PM之合并临床ILD存在不同的病情经过。CADM-ILD呈急进性ILD的临床模式,其6个月存活率仅为40．8%,中位数存活时间仅为10．2个月；而典型的DM-ILD呈现“次急进性”(sub-rapid progressive)的临床模式,5年存活率为54．0%,中位数存活时间为90个月；PM-ILD则为慢性经过,5年和10年存活率分别为72．4%和60．3%,中位数存活时间可达10年,部分DM-ILD和个别PM-ILD患者也可呈现急进性ILD的疾病模式。③Logistic回归显示：四肢近端肌力OR 3．374(95%CI 1．729～6．583,P＜0．01)和血沉OR 1．025 (95%CI 1．002～1．049,P=0．032)与临床ILD呈正相关,血白蛋白水平OR 0．877(95? 0．792～0．970,P= 0．011)则与临床ILD呈负相关。④随访CADM(28例)的病程为3～80个月,其中CADM-ILD超过半数在1年内死亡(12/21)；而病程＞24个月的CADM(8/28例)预后良好。对于无ILD的CADM,主要予中小剂量的激素(＜0．5～1mg·kg~(-1)·d~(-1))治疗,而CADM-ILD则多接受较大剂量的激素(≥1～2mg·kg~(-1)·d~(-1)),且多联用包括硫唑嘌呤、环磷酰胺、环孢素、霉酚酸酯在内的细胞毒药物,但对呈急进性ILD者缺乏疗效。⑤DM/PM随访病例的病死率为24．8%(36/145例),ILD及其并发症作为直接死因的占69．4%(25/36例),与ILD无直接相关的感染占25．0%(9/36例)。纵隔(皮下)气肿,气胸发生率占所有DM/PM-ILD的9．3%(8/86例),也是提示预后不良指征之一。结论ILD是DM/PM的常见并发症,也是最重要危险因素。本文提出了一个新的DM/PM疾病分类模式：即DM/PM是皮损、肌炎和ILD三个维度上相组合的立体疾病谱。CADM是该疾病谱的组成部分,CADM-ILD可呈急进性,是疾病谱中特殊的临床表型。     

多发性肌炎/皮肌炎合并间质性肺疾病的临床分析

目的探讨多发性肌炎/皮肌炎(PM/DM)合并间质性肺疾病(ILD)患者的临床表现、实验室检查、胸部影像学及肺功能的变化及意义。方法对住院的PM/DM并ILD患者7例(男性5例,女性2例,平均年龄55.7岁;5例为DM,2例为PM)均进行血清酶学和自身抗体测定、高分辨率CT(HRCT)及肺功能检查和皮肤肌肉活检。结果 6例患者出现酶学增高,以肌酸激酶(CK)和乳酸脱氢酶(LDH)增高明显;4例患者抗核抗体(ANA)(+),2例抗Jo-1抗体(+);皮肤肌肉活检病理诊断符合肌炎、皮肌炎改变。HRCT提示4例肺出现网点影及斑片阴影,3例出现双肺磨玻璃样病变和实变阴影。7例患者均出现限制性通气功能障碍,一氧化碳弥散量(DLCO)明显降低。6例患者使用糖皮质激素和免疫抑制剂治疗。5例患者治疗后病情稳定,1例患者死亡。结论 HRCT可以及早发现PM/DM肺部病变。CK明显增高和抗Jo-1抗体阳性是诊断DM/PM并ILD的重要指标。患者可出现严重的弥散功能低下,应用激素合并免疫抑制剂治疗可取得较好疗效。     

艾滋病合并结核病的临床分析

目的　探讨艾滋病合并结核病的临床特点。方法 对1998年至2002年11例艾滋病合并结核病进行临床分析。结果 (1)艾滋病感染途径:输血感染者8例,其他途径各1例。(2)合并肺结核病6例,其中继发性肺结核3例,原发性肺结核1例,血行播散性肺结核2例;合并肺外结核5例,其中结核性心包积液、结核性脑膜炎各2例,胸腔积液1例;合并多重感染者5例。(3)11例1:2000PPD试验均为阴性。(4)治疗:7例抗病毒与抗结核联合治疗,临床表现明显改善;3例仅抗结核治疗者中1例有效、2例死亡;1例未经任何治疗,6月死亡。结论 艾滋病合并结核病临床表现多样,血行播散性肺结核多,肺外结核多,多重感染多见,抗病毒与抗结核联合治疗有效。     

七例肺硬化性血管瘤误诊分析

目的　通过对肺硬化性血管瘤(Pulmonary Sclerosing Hemangioma,PSH)的误诊分析,提高对PSH的认识。方法 对7例经手术病理证实PSH病人的误诊原因进行回顾性分析。结果 本组7例男女之比为1:6,平均年龄52.3岁,误诊率100%。胸部X线多表现为孤立、圆形、类圆形、密度均匀、边缘光滑、无钙化结节状阴影。无肺门、纵膈淋巴结肿大。3例病人血CEA>10μg/L,1例痰结核杆菌阳性。结论 误诊原因:对PSH缺乏认识,易受年龄、化验等因素的影响。对肺部有孤立性病灶的女性病人应考虑到PSH。     

Short‐term and long‐term outcomes of interstitial lung disease in polymyositis and dermatomyositis: A series of 107 patients

Objective

This study was undertaken to assess the characteristics and outcome of interstitial lung disease (ILD) in polymyositis/dermatomyositis (PM/DM) and to determine variables predictive of ILD deterioration in PM/DM.

Methods

Among 348 consecutive patients with PM/DM, 107 patients with ILD were identified by medical records search in 4 medical centers. All patients underwent pulmonary function tests (PFTs) and pulmonary high‐resolution computed tomography (HRCT) scan.

Results

ILD onset preceded PM/DM clinical manifestations in 20 patients, was identified concurrently with PM/DM in 69 patients, and occurred after PM/DM onset in 18 patients. Patients with ILD could be divided into 3 groups according to their presenting lung manifestations: patients with acute lung disease (n = 20), patients with progressive‐course lung signs (n = 55), and asymptomatic patients with abnormalities consistent with ILD evident on PFTs and HRCT scan (n = 32). We observed that 32.7% of the patients had resolution of pulmonary disorders, whereas 15.9% experienced ILD deterioration. Factors that predicted a poor ILD prognosis were older age, symptomatic ILD, lower values of vital capacity and diffusing capacity for carbon monoxide, a pattern of usual interstitial pneumonia on HRCT scan and lung biopsy, and steroid‐refractory ILD. The mortality rate was higher in patients with ILD deterioration than in those without ILD deterioration (47.1% versus 3.3%).

Conclusion

Our findings indicate that ILD results in high morbidity in PM/DM. Our findings also suggest that more aggressive therapy may be required in PM/DM patients presenting with factors predictive of poor ILD outcome.

     

Interstitial lung disease in polymyositis and dermatomyositis: clinical course and response to treatment

OBJECTIVES: To assess the prevalence, clinical characteristics, and treatment options of patients with interstitial lung disease (ILD) in polymyositis and dermatomyositis (PM/DM). Patients and Methods: Sixty-three consecutive patients with PM/DM underwent standardized screening. Patients with ILD were monitored prospectively, and graded immunosuppression was administered according to the rate of clinical progression. RESULTS: ILD was diagnosed in 20 of 63 patients (32%). Generally, the clinical and serologic findings of the anti-Jo1 syndrome were present. Follow-up evaluation disclosed either a progressive or a nonprogressive course. The 10 patients with progressive ILD were distinguished from the nonprogressive group by extensive ground-glass opacities on high-resolution computed tomography (HRCT) and by bronchoalveolar lavage (BAL) neutrophilia. Intravenous pulse cyclophosphamide prevented further progression in all 10 patients and led to some functional improvement. In the 10 patients without rapidly progressive lung disease, immunosuppression of moderate intensity stabilized pulmonary findings during a median 35 months of follow-up. CONCLUSIONS: The prevalence of ILD in our patients with PM/DM was 32%; this emphasizes the need for pulmonary screening in all PM/DM patients. Progressive disease, featuring ground-glass opacities on HRCT and an inflammatory BAL cell profile, is amenable to intensive immunosuppression. Conversely, patients who do not have these HRCT and BAL features appear to have a low risk of pulmonary deterioration. RELEVANCE: Because the treatment for ILD seems to depend on the rate of clinical progression, future therapeutic trials of lung disease in PM/DM should stratify patients accordingly.     

Flowcytometric analysis of bronchoalveolar lavage fluid cells in polymyositis/dermatomyositis with interstitial pneumonia

OBJECTIVE: Interstitial lung disease (ILD) is a complication occurring in 10-30% of patients with polymyositis/dermatomyositis (PM/DM) as well as in those with progressive systemic sclerosis (PSS). Clinical features are different between these two disease states, notably with respect to the duration of manifestations, pathological findings, response to steroid therapy etc. However, dissimilarities in pulmonary inflammatory cell characteristics, which, if present at all, would be of critical importance, remain as yet to be clarified. METHODOLOGY: The phenotypes of lymphocytes and alveolar macrophages in bronchoalveolar lavage fluid (BALF) were analysed to elucidate phenotypic peculiarity of pulmonary inflammatory cells of ILD in PM/DM. Eight PM/DM patients with ILD (mean age 47.9 years) were examined by bronchofibrescopy under local anaesthesia. Bronchoalveolar lavage was performed from the right middle lobe using four 50 mL aliquots of normal saline and the recovered fluid was compared with BALF of ILD in PSS. RESULTS: Bronchoalveolar lavage fluid cells of PM/DM patients with ILD showed an increased percentage of CD8+ lymphocytes, in particular CD8+ histocompatibility leucocyte antigen-DR positive lymphocytes and CD8+ CD11b-lymphocytes, both of which represent cytotoxic T cells. However, phenotypic differences in these lymphocytes were not found between PM and DM. The percentage of alveolar macrophages with expression of histocompatibility leucocyte antigen-DQ was significantly different among the three groups (PM/DM, PSS, healthy volunteers). CONCLUSIONS: Cytotoxic T cells may be major pulmonary inflammatory cells of ILD in PM/DM with no apparent difference between PM and DM. In contrast, ILD in PSS was suggested as being likely to be characterized by activated macrophage.     

Interstitial lung disease in polymyositis and dermatomyositis

OBJECTIVES: To assess prevalence, characteristics, and long-term outcome of interstitial lung disease (ILD) in polymyositis (PM) and dermatomyositis (DM). To determine predictive variables of ILD course in PM/DM, and to define both clinical and biochemical features associated with ILD onset in PM/DM. METHODS: The medical records of 156 consecutive PM/DM patients in 3 medical centers were reviewed. RESULTS: Thirty-six PM/DM patients (23.1%) developed ILD. We observed that 19.4% of patients with ILD had resolution of pulmonary disorders, whereas 25% experienced ILD deterioration. Morbidity and mortality rates were as high as 13.9% and 36.4%, respectively, in PM/DM patients with ILD. Parameters of PM/DM that related to ILD poor outcome were identified as follows: Hamman-Rich-like pattern, initial diffusing capacity of carbon monoxide <45%, neutrophil alveolitis, and histologic usual interstitial pneumonia. Additionally, for the group with ILD, polyarthritis, higher values of erythrocyte sedimentation rate and C-reactive protein, presence of anti-Jo-1 antibody, and characteristic microangiopathy were significantly more frequent. CONCLUSION: Our series underlines the high frequency of ILD in PM/DM patients, resulting in increased morbidity and mortality rates. It also indicates that PM/DM patients should routinely be screened for ILD, even those patients without anti-Jo-1 antibody, because 69% of our ILD patients were seronegative for the anti-Jo-1 antibody. Our findings further suggest that PM/DM patients presenting with factors predictive of ILD poor outcome may require more aggressive therapy.     

Adult clinically amyopathic dermatomyositis with rapid progressive interstitial lung disease: a retrospective cohort study

The aim of the study was to investigate the characteristics of adult clinically amyopathic dermatomyositis (CADM) with rapid progressive interstitial lung disease (ILD). Hospitalized patients with dermatomyositis (DM) and polymyositis (PM) between 1998 and 2005 in the Shanghai Renji Hospital were retrospectively studied. One hundred and forty-five patients were classified into CADM, classic DM or PM according to the modified Sontheimer's definition or Bohan-Peter's classification criteria. They were further stratified based on the presence or absence of clinical ILD. The Kaplan-Meier survival analysis and COX regression were performed. The predictive factors for ILD and other clinical properties of CADM-ILD were explored. The presence of clinical ILD was a significant risk factor for the poor outcome of DM/PM (OR = 4.237, CI 95%: 1.239-14.49, p = 0.021). Other risk factors are the presence of rashes and elevated urea nitrogen. Patients with DM/PM complicated by ILD had different clinical courses. Patients with CADM-ILD showed a rapidly progressive pattern with 6-month survival rate of 40.8%. The DM-ILD manifested a progressive pattern with a 5-year survival rate of 54%, while PM-ILD was chronic with 5- and 10-year survival rate of 72.4% and 60.3%, respectively. Better preserved muscle strength, elevated erythrocyte sedimentation rate, and hypoalbuminemia may herald ILD in DM/PM. Patients with CADM-ILD who later died had lower PO(2), higher lactate dehydrogenase, and prominent arthritis/arthralgia compared with those who survived. The presence of antinuclear antibody seems to be protective. Rapid progressive CADM-ILD is refractory to conventional treatment. ILD is a common complication in over 40% of our hospitalized DM/PM cohort and is also a prominent prognostic indicator. CADM is a special phenotype of DM/PM. CADM-ILD, which is usually rapidly progressive and fatal, requires further investigation.     

Interstitial lung disease in polymyositis and dermatomyositis: longitudinal evaluation by pulmonary function and radiology

OBJECTIVE: To estimate predictors and long-term outcome of interstitial lung disease (ILD) in patients with polymyositis (PM) and dermatomyositis (DM). METHODS: We conducted a prospective study in which newly diagnosed PM/DM patients, regardless of clinical symptoms of pulmonary disease, were investigated with repeated chest radiography, high-resolution computed tomography (HRCT) of the lungs, and pulmonary function test (PFT). Clinical, radiologic, and lung function outcome was based on the last followup results. RESULTS: Twenty-three patients with a mean followup period of 35 months were included. Findings on radiographic examination and/or PFT compatible with ILD were recorded in 18 patients (78%). Patients with ILD had lower lung function, higher radiologic scores, and higher creatine kinase values than those without ILD. All patients were treated with high-dose glucocorticoids and other immunosuppressive agents. Two patients died due to ILD, both with active myositis. During the followup, total lung capacity (TLC) improved in 33%, remained stable in 39%, and deteriorated in 28%. Changes in TLC correlated only partially with HRCT findings, which persisted even after normalizing for lung function. CONCLUSION: ILD associated with PM/DM is in most cases mild, chronic, and has a nonprogressive course during immunosuppressive treatment. PFT can be normalized during treatment with immunosuppressive therapy, even if radiologic signs of ILD persist. The course of ILD could not be predicted on the first examination. Therefore, myositis patients with ILD need careful evaluation of clinical features as well as PFT and radiologic features during followup.     

KL-6: a serological biomarker for interstitial lung disease in patients with polymyositis and dermatomyositis

Abstract. Fathi M, Barbasso Helmers S, Lundberg IE (Karolinska University Hospital, Stockholm; Karolinska Institutet, Karolinska University Hospital, Stockholm; and Institute of Environmental Medicine, Karolinska Institutet, Stockholm; Sweden). KL‐6: a serological biomarker for interstitial lung disease in patients with polymyositis and dermatomyositis. J Intern Med 2012; 271 : 589–597. Objectives. To investigate whether Caucasian patients with polymyositis (PM) or dermatomyositis (DM) and interstitial lung disease (ILD) have elevated serum levels of KL‐6 compared with patients without ILD and whether KL‐6 could be used as a marker for ILD activity and treatment efficacy of ILD in PM/DM. Design and methods. Thirty patients with PM/DM (seven with ILD) and 17 age‐ and sex‐matched healthy controls were included in a retrospective, cross‐sectional analysis. Twelve patients were followed for longitudinal evaluation. ILD was defined as restrictive lung function impairment with radiographic signs of ILD. Serum KL‐6 levels were measured using a sandwich enzyme immunoassay kit. Groups were compared by Mann–Whitney U‐test. Results. PM/DM patients with ILD had significantly higher median serum KL‐6 levels compared with those without ILD: 995 (range 533–2318) versus 322 (range 132–1225) U mL^?1 (P = 0.0002). Median serum levels of healthy controls were 225 (range 136–519) U mL^?1. Serum levels of KL‐6 were inversely correlated with percentages of forced expiratory volume in 1 s (FEV₁), vital capacity (VC), total lung capacity (TLC), forced VC, diffusing capacity of carbon monoxide (DLco), maximal voluntary ventilation at 40 breaths min^?1 and residual volume (RV). Changes in KL‐6 levels showed a significant inverse correlation with changes in percentage FEV₁, TLC, DLco and RV. At a cut‐off level of 549 U mL^?1 (mean ± 2.5 SD for controls), the sensitivity and specificity for diagnosis of ILD were 83% and 100%, respectively. Conclusion. The level of serum KL‐6 may serve as measure of ILD in patients with PM/DM and is a promising biomarker for use in clinical practice to assess clinical response to treatment.     

Unusually high frequency of autoantibodies to PL-7 associated with milder muscle disease in Japanese patients with polymyositis/dermatomyositis

OBJECTIVE: Autoantibodies to aminoacyl transfer RNA synthetases, such as histidyl (Jo-1), threonyl (PL-7), alanyl (PL-12), glycyl (EJ), and isoleucyl (OJ), are closely associated with a subset of patients with polymyositis/dermatomyositis (PM/DM) complicated by interstitial lung disease (ILD). Anti-Jo-1 is by far the most common, found in 15-25% of patients with PM/DM, whereas the other types are found in only approximately 3% of these patients. In this study, the clinical associations of these autoantibodies in Japanese patients with PM/DM were investigated. METHODS: The diagnoses of PM/DM and amyopathic DM (ADM) were based on the Bohan and Peter criteria and Sontheimer's definition, respectively. Sera from 36 Japanese patients with PM/DM (13 with PM, 20 with DM, 3 with ADM) were screened by immunoprecipitation and by enzyme-linked immunosorbent assay (for Jo-1). Clinical and laboratory data were collected. RESULTS: The frequencies of autoantibodies to Jo-1 (22%) and to EJ, OJ, and PL-12 (3-6%) were similar to those found in previous studies, including studies of Japanese subjects. However, anti-PL-7 was found in 17% of patients, in contrast to a frequency of 1-4% in previous studies (P < 0.02-0.0002). The 6 anti-PL-7-positive patients were not related, and no skewing in year or month of disease development, place of residence or work, or occupation was found. All patients had ILD, consistent with the clinical features of antisynthetase-positive patients. The patients with anti-PL-7 had lower serum muscle enzyme levels and milder muscle weakness (P < 0.05) compared with anti-Jo-1-positive patients. CONCLUSION: Anti-PL-7 was found at an unusually high frequency in this group of Japanese patients with myositis. Although anti-PL-7, similar to anti-Jo-1, is associated with PM/DM with ILD, muscle involvement in the patients with anti-PL-7 appeared to be milder than that in the anti-Jo-1 subset.     

Prevalence of interstitial lung disease in polymyositis and dermatomyositis: A meta-analysis from 2000 to 2020

ObjectiveInterstitial lung disease (ILD) is the most important prognostic factor for mortality in patients with polymyositis (PM) and dermatomyositis (DM), but the prevalence of ILD in PM/DM may vary between countries. The aim of this study was to determine the overall prevalence of ILD in global patients with PM/DM.MethodsWe performed a systematic literature review of studies published from Jan 1, 2000 to April 30, 2020 on ILD and PM/DM. We extracted data and pooled the prevalence by using a random-effect model due to high heterogeneity. Heterogeneity was assessed by subgroup analysis and sensitivity analysis.ResultsA total of 34 studies with 10,130 patients were included in our meta-analysis. Pooled data demonstrated that the global prevalence of ILD in patients with PM/DM was 0.41 (95% confidence interval [CI] 0.35–0.48). However, this prevalence varied with geographical locations and time trends. The prevalence of ILD in PM/DM was 0.5 (95% CI 0.42–0.57) in Asia, 0.23 (95% CI 0.15–0.31) in America, and 0.26 (95% CI 0.18–0.34) in Europe. A higher prevalence of ILD was reported in studies published in 2011–2015 (0.43, 95% CI 0.34–0.52) and 2016–2020 (0.45, 95% CI 0.35–0.54), compared with those published in 2000–2010 (0.27, 95% CI 0.16–0.39). The pooled prevalence of ILD in patients with DM, PM, and clinically amyopathic dermatomyositis subtype was 0.42 (95% CI 0.35–0.49), 0.35 (95% CI 0.27–0.42), and 0.53 (95% CI 0.32–0.74), respectively. Patients with anti-Jo-1 and anti-melanoma differentiation-associated gene 5 antibodies were more likely to develop ILD than other myositis-specific autoantibodies.ConclusionThe global prevalence of ILD in patients with PM/DM was approximately 41% and the condition was predominant in Asians. This highlights potential genetic and environmental differences in the pathogenesis of ILD in patients with PM/DM. More studies are required to elucidate the specific associations.