Serological markers of basement membrane collagen type IV and laminin are increased in systemic lupus erythematosus but differentially expressed in patients with previous cardiovascular events.

OBJECTIVES: To assess basement membrane remodelling in systemic lupus erythematosus (SLE) by studying serum levels of type IV collagen (C4M) and laminin (LG1M) fragments and their association with disease profile. METHODS: One hundred and six SLE patients without and 20 with previous cardiovascular events were included. One hundred and twenty male and female blood donors served as controls. Disease activity score (SLEDAI-2K) and cumulated damage index (SLICC-DI) were calculated. Coronary artery calcification (CAC) was studied by CT scan. Carotid intima-media thickness (IMT) was measured by ultrasound. C4M and LG1M were quantified by ELISAs. RESULTS: Serum levels of LG1M and C4M were significantly increased in the entire SLE cohort, median (IQR) 15.8 (26.16) ng/ml vs. 5.5 (5.8) ng/ml (±9.4), p<0.0001 and 31.3 (20.0) vs. 21.6 (9.2) ng/ml, p<0.0001. C4M and LG1M were mutually interrelated in patients and controls, r=0.44 (p<0.0001) and r=0.42 (p<0.0001). LG1M was significantly higher in patients with previous cardiovascular events (CVE), 27.2 (30.8) vs. 14.1 (21.4) p<0.03, while C4M did not differ between these subsets. LG1M, but not C4M, was borderline higher in anti-phospholipid antibody-positive patients vs. negatives (p=0.08). There was a weak correlation between LG1M and SLICC-DI, r=0.22 (p=0.01), but no associations between these markers and criterial lupus manifestations or asymptomatic atherosclerosis. CONCLUSIONS: These findings indicate that remodelling of collagen type IV and laminin is increased in SLE unrelated to disease activity, presumably reflecting clinically silent disease progression. The selective association of increased LG1M and cardiovascular events may represent a distinctive aspect of SLE-related vessel wall repair.

Prevalence of Newly Diagnosed Malignancies in Patients with Polymyalgia Rheumatica and Giant Cell Arteritis, Comparison of 18F-FDG PET/CT Scan with Chest X-ray and Abdominal Ultrasound: Data from a 40 Week Prospective, Exploratory, Single Centre Study.

The aim of the study was to identify the prevalence of newly diagnosed malignancies in patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA), with the aid of 18F-FDG PET/CT scan compared to conventional imaging techniques: Chest X-ray (CXR) and abdominal ultrasound (US). Secondarily, to examine the relative diagnostic accuracy of these two imaging modalities for the detection of cancer. Eighty consecutive patients with newly diagnosed PMR, GCA, or concomitant PMR and GCA, were included and followed up for 40 weeks. All patients underwent an 18F-FDG PET/CT scan, CXR, and abdominal US at diagnosis. Imaging findings were dichotomously categorized into malignant or benign. Among 80 patients, three patients were diagnosed with seronegative rheumatoid arthritis and were excluded from the analysis. Of the remaining 77, 64 (83.1%) patients were diagnosed with pure PMR, 3 (3.9%) with pure GCA, and 10 (13.0%) with concomitant PMR and GCA. Five types of cancer that were more prevalent than the one-year prevalence of 1.2% among the background population were found in four (5.2%; 95%CI: 1.4-12.8%) patients. CXR/abdominal US could detect the solid cancer in one patient, whereas 18F-FDG PET/CT could identify all four solid cancers. Furthermore, four (5.2%; 95%CI: 1.4-12.8%) cases of monoclonal gammopathy of undetermined significance (MGUS) were found. An increase in C reactive protein (CRP) implicated an increased risk for cancer of 2.4% (OR: 1.024, 95%CI: 1.001-1.047; p = 0.041). 18F-FDG PET/CT can reveal occult cancers at an early stage with a high negative predictive value, and it is specifically beneficial in PMR/GCA patients with nonspecific symptoms.