Caeruloplasmin, prealbumin and alpha 2-macroglobulin as potential indices of disease activity in different arthritides

Alteration of gut microbiota in Henoch-Schönlein purpura children with gastrointestinal involvement

BACKGROUND

The compositional and structural changes of gut microbiota were closely related to the status of Henoch-Schönlein purpura (HSP).

AIMS

To investigate if clinical indicators and gut microbiota differ between HSP patients with or without gastrointestinal (GI) involvement and to explore the alterations of fecal microbiota in HSP children with and without GI symptoms.

METHODS

A total of 22 children with HSP were enrolled in the study. Fecal microbiota composition was analyzed by 16S rRNA sequencing. Clinical indicators, fecal microbial diversity, and compositions were compared between the two groups.

RESULTS

Respectively, 9 patients with GI involvement (HSP-A) and 13 patients without GI involvement (HSP-N) were enrolled. Prealbumin (PA) and the ratio of immunoglobulin A (IgA) / complement (C)3 were significantly decreased in the HSP-A group and an elevated D-dimer was found in the HSP-N group. The relative abundances of Blautia, Lachnospira, and Haemophilus were significantly higher in the HSP-A group compared to HSP-N. Lower levels of unidentified Prevotellaceae, Parabacteroides, and Romboutsia were found in HSP-A patients. The linear discriminant analysis effect size (LEfSe) showed that the biomarkers for the HSP-A group included Blautia, Anaerostipes, Veillonella, Lachnospira, and Haemophilus. For the HSP-N group, unidentified Prevotellaceae, Intestinibacter, Romboutsia, and Akkermansia were the prominent biomarkers at the genus level. Additionally, the ratio of IgA/C3 exhibited a negative correlation with the genus Blautia. Meanwhile, PA showed negatively correlation with Veillonella.

CONCLUSIONS

These results provide a broader understanding for future microbial-based therapies to decrease the development of GI involvement and improve the clinical outcome of HSP in children.

A Cohort Study of Liver Involvement in Patients With Adult-Onset Still's Disease: Prevalence, Characteristics and Impact on Prognosis

Objective: Adult-onset Still's disease (AOSD) is a systemic disorder commonly accompanied by liver involvement. This study aims to illustrate the detailed information of liver abnormalities in patients with AOSD and evaluate the impact on the prognosis.

Methods: A total number of 128 hospitalized patients, who met the Yamaguchi criteria of AOSD in the Department of Rheumatology and Immunology, Ruijin Hospital from July 2016 to August 2019 were consecutively enrolled and followed up. The demographic characteristics, clinical features, laboratory tests, treatments and prognosis were recorded. Correlations of liver function tests (LFTs) with disease activity and laboratory parameters were analyzed by the Spearman test. Risk factors of the refractory AOSD were evaluated by multivariate logistic regression analysis.

Results: Liver involvement was presented in 104 (81.3%) patients with AOSD. We observed that 34 (32.7%) patients were with mild elevation, 32 (30.8%) patients were with moderate elevation, and 38 (36.5%) patients were with severe elevation. The majority of elevated ALT, AST and ALP decreased to normal within the range of 2 months, except for GGT. Furthermore, the LFTs were found significantly correlated with disease activity. Besides, we found patients with higher levels of LFTs tended to require more intensive treatments and suffered from poorer prognosis. Multivariate logistic regression analysis showed ALP ≥ 141 IU/L and GGT ≥ 132 IU/L are independent risk factors of refractory AOSD.

Conclusion: Liver involvement is common in patients with AOSD, the levels of LFTs are associated with disease activity and related to the treatment strategies and prognosis.

Biomarker development for axial spondyloarthritis

The term axial spondyloarthritis (axSpA) encompasses a heterogeneous group of diseases that have variable presentations, extra-articular manifestations and clinical outcomes, and that will respond differently to treatments. The prototypical type of axSpA, ankylosing spondylitis, is thought to be caused by interaction between the genetically primed host immune system and gut microbiota. Currently used biomarkers such as HLA-B27 status, C-reactive protein and erythrocyte sedimentation rate have, at best, moderate diagnostic and predictive value. Improved biomarkers are needed for axSpA to assist with early diagnosis and to better predict treatment responses and long-term outcomes. Advances in a range of 'omics' technologies and statistical approaches, including genomics approaches (such as polygenic risk scores), microbiome profiling and, potentially, transcriptomic, proteomic and metabolomic profiling, are making it possible for more informative biomarker sets to be developed for use in such clinical applications. Future developments in this field will probably involve combinations of biomarkers that require novel statistical approaches to analyse and to produce easy to interpret metrics for clinical application. Large publicly available datasets from well-characterized case-cohort studies that use extensive biological sampling, particularly focusing on early disease and responses to medications, are required to establish successful biomarker discovery and validation programmes.

Serum inflammatory biomarkers fail to identify early axial spondyloarthritis: results from the SpondyloArthritis Caught Early (SPACE) cohort

Introduction

Decreasing the diagnostic delay in axial spondyloarthritis (axSpA) remains a major challenge. Here, we assessed the value of serum inflammatory biomarkers to distinguish early axSpA from other pathologies in a large cohort of patients referred with early back pain.

Methods

Serum c reactive protein (CRP), erythrocyte sedimentation rate (ESR) and calprotectin were determined in the SPondyloArthritis Caught Early (SPACE) cohort (n=310), an early back pain inception cohort. Additionally, explorative serum biomarkers derived from the literature (interleukin-27 (IL-27), human β-defensin-2 (hBD-2) and lipcolin-2 (LCN-2)) were determined by ELISA in full-blown patients with ankylosing spondylitis (AS) (n=21) and healthy controls (n=20).

Results

Serum CRP and ESR levels were not elevated in early axSpA versus ‘control’ back pain patients. Serum calprotectin was elevated in early axSpA versus controls (p=0.01) but failed to identify early axSpA at the individual level (positive predictive value of 38.7%). As to explorative biomarkers, serum levels of IL-27 were not detectable, and hBD-2 and LCN-2 serum levels were not elevated in full-blown AS versus healthy controls (p=0.572, p=0.562, respectively). Therefore, these markers were not further determined in the SPACE cohort.

Conclusions

None of the candidate serum inflammatory markers were useful as diagnostic markers in the early phase of axSpA.

Calprotectin (S100A8/9) as serum biomarker for clinical response in proof-of-concept trials in axial and peripheral spondyloarthritis

Introduction

Biomarkers complementing clinical evaluations may help to reduce the length and size of proof-of-concept (PoC) trials aimed to obtain quick “go/no go” decisions in the clinical development of new treatments. We aimed to identify and validate serum biomarkers with a high sensitivity to change upon effective treatment in spondyloarthritis (SpA) PoC trials.

Methods

The candidate biomarkers high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), pentraxin-3 (PTX-3), alpha-2-macroglobulin (alpha-2-MG), matrix metalloproteinase-3 (MMP-3), calprotectin, and vascular endothelial growth factor (VEGF) were determined by enzyme-linked immunosorbent assay (ELISA) in healthy controls (n = 20) and SpA patients before and after 2 weeks of infliximab (n = 18) or placebo (n = 19) treatment in cohort 1. Clinical outcome was evaluated at week 12. Results were validated in ankylosing spondylitis (AS) with infliximab (cohort 2, n = 21) and peripheral SpA with etanercept (cohort 3, n = 20).

Results

Serum levels of calprotectin, hs-CRP, PTX-3, VEGF (all P < 0.001) and MMP-3 (P = 0.062), but not IL-6 and alpha-2-MG, were increased in SpA versus healthy controls. Treatment with infliximab, but not placebo, significantly decreased calprotectin (P < 0.001) and hs-CRP (P < 0.001) levels, with a similar trend for MMP-3 (P = 0.063). The standardized response mean (SRM), which reflects the ability to detect changes over time, was high for calprotectin (−1.26), good for hs-CRP (−0.96) and moderate for MMP-3 (−0.52). Calprotectin and hs-CRP, but not MMP-3, were good biomarkers for treatment response in axial and peripheral SpA as evaluated and confirmed in cohort 2 and 3 respectively.

Conclusions

Calprotectin and hs-CRP are good serum biomarkers with high sensitivity to change upon effective treatment at the group level in small-scale, short term PoC trials in SpA.

Laboratory findings and pathology of psoriatic arthritis

Over recent years there has been a great deal of interest in the immunology, molecular biology and pathology of psoriasis and PsA. The pathogenetic mechanisms in PsA are less well understood than those described for psoriasis. There are almost certainly genetic and immune components. What is not clear is whether there is a primary immune defect or whether unknown stimuli lead to the recruitment of the immune system and establishment of the disease; nor is it absolutely clear whether PsA is an extension of psoriasis in certain prone individuals. Vascular abnormalities are the earliest histopathological changes to occur in the psoriatic plaque and are also prominent in the psoriatic synovium. Espinoza et al (1982) have suggested there may be a primary vascular defect in PsA. The fact that vascular changes occur before infiltration of immunocompetent cells and are the first changes to resolve with treatment of psoriasis is likely to be significant. Abnormalities in the cellular kinetics and growth factor sensitivity of keratinocytes, fibroblasts and synoviocytes have been highlighted previously. The ability of these cells to produce growth factors and express HLA class II antigens demonstrates the potential for them to initiate and maintain inflammation. The development and possible increased incidence of PsA in patients with such profound immunodeficiency as acquired immune deficiency syndrome suggests that T helper cells do not play a significant role in the establishment of the disease (Arnett et al, 1991). Previously, many immune changes were described. Unfortunately they are non-specific and do not indicate a fundamental defect or marker of PsA. Vasey (1985) has suggested that insidious exposure to Gram-positive bacteria from the gut, tonsils and psoriatic plaques results in chronically stimulated monocytes, macrophages and dendritic cells. These cells are able to migrate throughout the body. Repeated microtrauma may result in the homing of these cells to sites of injury in the skin, synovium and tendons. Interaction with genetically hyperactive synoviocytes and keratinocytes with concomitant release of growth factors may precipitate early lesions of psoriasis and PsA. This hypothesis needs to be substantiated, but it ties together some of the varying observations seen. Many abnormal laboratory findings have been described. Unfortunately, none of the serological changes is sufficiently specific to be of great help in diagnosis. CRP levels and the ESR remain the best promise as markers of the inflammatory component of the arthritis, while other indicators correlate with certain facets of the disease pathology, but as yet have not found a true niche in the management of PsA.(ABSTRACT TRUNCATED AT 400 WORDS)

Caeruloplasmin concentration and oxidase activity in polyarthritis

Caeruloplasmin (Cp) concentration and oxidase activity have been shown to be elevated in rheumatoid arthritis (RA) and psoriatic arthritis, but normal in Reiter's syndrome, Behcet's syndrome and juvenile seronegative polyarthritis. Synovial fluid Cp was significantly depressed in comparison with serum Cp in RA. During second-line therapy in RA, Cp concentration and activity fell significantly (P less than 0.001), but the change in Cp did not correlate with plasma viscosity.