Association of serum KL-6 levels with interstitial lung disease in patients with connective tissue disease: a cross-sectional study

Abstract

It was aimed to evaluate KL-6 glycoprotein levels to determine if it may be a diagnostic marker for the connective tissue diseases (CTDs) predicting CTD-related interstitial lung diseases (ILDs) (CTD-ILD) development and to examine if there was a difference between patients and healthy controls. The study included 113 patients with CTD (45 CTD without lung involvement, 68 CTD-ILD) and 45 healthy control subjects. KL-6 glycoprotein levels were analyzed with ELISA in patients and the control group. The relationship between KL-6 glycoprotein levels and CTD-ILD was assessed. In the comparison of all the groups in the study, significantly higher levels of KL-6 were determined in the CTD-ILD group than in either the CTD without pulmonary involvement group or the healthy control group (p < 0.008 and p < 0.001, respectively). There was no statistically significant difference between the KL-6 levels in the healthy control group and the CTD without pulmonary involvement group (p = 0.289). The KL-6 levels did not differ significantly according to the connective tissue diseases in the diagnostic groups (systemic lupus erythematosus, Sjögren's syndrome, rheumatoid arthritis, mixed connective tissue disease, scleroderma, polymyositis/ dermatomyositis). In the healthy control group, there was a statistically significant difference between KL-6 levels in smokers and non-smokers. Smokers had significantly higher serum KL-6 levels compared with non-smokers (p < 0.05). There was no statistically significant difference between smoking status (pack-year) and serum KL-6 levels. There was no statistically significant correlation between serum KL-6 levels and time since diagnosis of CTD and CTD-ILD. The level of KL-6 as a predictive factor could be used to identify the clinical development of ILD before it is detected on imaging modality. Further prospective clinical studies are needed to define whether levels of KL-6 might have prognostic value or might predict progressive ILD.

Tumor-Associated Antigens in Rheumatoid Arthritis Interstitial Lung Disease or Malignancy?

“…Studies have been reported on biomarkers that may predict early pulmonary involvement in patients with connective tissue diseases and RA. [14][15][16][17] It is considered that tumor markers may be associated with low inflammatory activity and pulmonary involvement of rheumatic diseases. 10 Therefore, the association of tumor markers with lung involvement in rheumatic diseases is a research topic.…”

Prognostic role of blood KL-6 in rheumatoid arthritis–associated interstitial lung disease

“…Several reports have shown that KL-6 would be useful for early diagnosis as well as predicting acute exacerbation, treatment outcomes, and survival in patients with IPF [17,18,[34][35][36][37]. KL-6 might also serve as a diagnostic marker in connective tissue disease-associated ILD (CTD-ILD) [38]. Oguz et al, in 113 patients with CTD and 45 healthy control subjects, reported that median KL-6 values were higher in the CTD-ILD group than the CTD-without-ILD group (33.75 vs. 3.9 U/mL; P < 0.001) or healthy control group (33.75 vs. 3.9 U/mL; P < 0.008), respectively [38].…”

“…KL-6 might also serve as a diagnostic marker in connective tissue disease-associated ILD (CTD-ILD) [38]. Oguz et al, in 113 patients with CTD and 45 healthy control subjects, reported that median KL-6 values were higher in the CTD-ILD group than the CTD-without-ILD group (33.75 vs. 3.9 U/mL; P < 0.001) or healthy control group (33.75 vs. 3.9 U/mL; P < 0.008), respectively [38]. Our study showed the usefulness of KL-6 as a blood biomarker for estimating disease severity in RA-ILD.…”

Oral Presentation Abstracts

“…Prevalence and risk factors of musculoskeletal complaints in a multiethnic Surinamese population: preliminary results of the COPCORD Suriname study N. HO-A-THAM 1,4 , R. BASANTRAM, R. WITTOEK 2 , Y. VANLANDEWIJCK 3 , W. DANKAERTS syndecan-1 levels of saliva and plasma in 37 SJS patients and 34 normal controls (NC) and performed disease activity indexes, salivary gland scan and serologic markers in patients. ESS-DAI and ESSPRI scores of patients were 3.78 AE 3.33 and 3.95 AE 1.50, respectively.…”

“…Recently, it was proposed that the Villefranche criteria could be more stringent in the way that at least all three major manifestations mentioned above need to be present to establish an unequivocal clinical diagnosis of cEDS, which was useful and sufficient confirmed in two studies. 3,4 cEDS is caused by mutations in the type V collagen. Over 90% of patients which strictly satisfy all major Villefranche criteria for cEDS harbor a type V collagen defect.…”