Performance of ultrasound to assess erosion progression in rheumatoid arthritis

OBJECTIVES

To analyse the performance of ultrasonography (US) to detect bone erosion progression at the patient level and at the joint level by the US score for erosions (USSe) in early-stage and late-stage rheumatoid arthritis (RA) over a 2-year follow-up.

METHODS

Clinical and demographic information was recorded at baseline, and hands and feet RX were scored according to the Sharp erosion score. USSe was performed at baseline and over 2 years of follow-up on six bilateral joints (MCP2, 3, 5; MTP2, 3, 5). Inter-examiner reproducibility was performed on 14 patients, and the smallest detectable change (SDC) was calculated. US progression was defined as a change in USSe > SDC.

RESULTS

71 patients were included: 22 (31.0 %) early RA, and 49 (69.0 %) late RA. The intra-class correlation coefficient values of the USSe for intra- and inter-examiner studies were 0.96 (CI95: 0.93-0.98), and 0.92 (CI95: 0.75-0.97), respectively. On US, erosions prevailed at baseline in MTP5 joints followed by MCP2 and MCP5 joints. With an SDC calculated at 2.3, 28 patients (39.4 %) were classified as progressors, 30 (42.3 %) were stable, and 13 (18.3 %) were regressors during the follow-up. At the joint level, erosion progression was significant on the MCP2 and MTP5 joints in early RA (p < 0.01) and on the MCP5 and MTP5 joints for all RA (p < 0.05).

CONCLUSIONS

US is a highly reproducible method that is able to detect erosion progression at the patient level for both early and late RA and at the joint level (MCP2 and MTP5) for only early RA.

SARS-CoV-2 immunochromatographic IgM/IgG rapid test in pregnancy: A false friend?

BACKGROUND

An increasing body of evidence has revealed that SARS-CoV-2 infection in pregnant women could increase the risk of adverse maternal and fetal outcomes. Careful monitoring of pregnancies with COVID-19 and measures to prevent neonatal infection are warranted. Therefore, rapid antibody tests have been suggested as an efficient screening tool during pregnancy.

CASES

We analysed the clinical performance during pregnancy of a rapid, lateral-flow immunochromatographic assay for qualitative detection of SARS-CoV-2 IgG/IgM antibodies. We performed a universal screening including 169 patients during their last trimester of pregnancy. We present a series of 14 patients with positive SARS-CoV-2 immunochromatographic assay rapid test result. Immunochromatographic assay results were always confirmed by chemiluminescent microparticle immunoassays for quantitative detection of SARS-CoV-2 IgG and IgM+IgA antibodies as the gold standard. We observed a positive predictive value of 50% and a false positive rate of 50% in pregnant women, involving a significantly lower diagnostic performance than reported in non-pregnant patients.

DISCUSSION

Our data suggest that although immunochromatographic assay rapid tests may be a fast and profitable screening tool for SARS-CoV-2 infection, they may have a high false positive rate and low positive predictive value in pregnant women. Therefore, immunochromatographic assay for qualitative detection of SARS-CoV-2 IgG/IgM antibodies must be verified by other test in pregnant patients.

AB1125 PERFORMANCE OF ULTRASOUNDS TO ASSESS EROSION PROGRESSION IN RHEUMATOID ARTHRITIS

Background:

Ultrasonography (US) can detect more erosions than radiography (RX) at the joint level in rheumatoid arthritis (RA), especially at an early stage of the disease.

Objectives:

The aim of the study is to determine the ability of ultrasonography to detect erosion progression by the US Score for erosions (USSe), in early (less than 2 years disease duration (DD)) and late stage (more than 2 years DD) RA over two years of follow-up.

Methods:

Patients fulfilling ACR 1987 and/or ACR/EULAR 2010 criteria for RA were prospectively included. Clinical and demographic informations were recorded at baseline and hands and feet RX were scored according to the Sharp erosion score (SHSe). Erosive RA on RX was defined by the presence of at least three eroded joints (1). US examinations were performed at baseline and during the two years of follow-up. Erosions were scored by US on six bilateral joints (MCP 2, 3, 5 and MTP 2, 3, 5) with a four grade-scale to calculate total USSe. Erosive RA on US was defined by presence of one erosion ≥ 2mm (2). Inter-examiner reproducibility was performed on 14 patients in order to calculate the smallest detectable change (SDC), which was 2.3. Ultrasonographic progression was defined as a change in USSe > 2 (erosion change > SDC).

Results:

A total of 71 patients were included, 22 patients (31.0%) had early RA and 49 (69.0%) patients had late RA diseases. On RX, 30 (42.3%) patients were erosive at baseline with a mean SHSe at 29.4 (SD at 24.7). On US, 63 patients (88.7%) were classified as eroded. On US, erosions prevailed at baseline in MTP5 joints, then MCP2 and MCP5 joints on their lateral facets. During follow-up, 28 patients (39.4%) were classified as US progressors, 30 (42.3%) were stable and 13 (18.3%) considered as regressors (figure 1). In early RA disease, three of the four non eroded patients became eroded. USSe progressed in 11 patients (50%) while regression was observed in only one patient. In late RA disease, 17 patients (34.7%) progressed and 12 patients (24.5%) decreased significantly their USSe. Erosion progression prevailed on MTP 5 joints followed by MCP2 and finally MCP5 joints (figure 2).

Figure 1.

USSe progression plots (n=71)

Figure 2.

Differences of USSe by joints during follow-up in early and late RA

Conclusion:

US structural examination is a highly reproducible method to assess erosion in RA disease. The USSe is able to detect structural changes (progression, stabilization and regression) in RA patients during a follow-up of two years especially in RA patients with short disease duration.

References:

[1]Van der Heijde D, van der Helm-van Mil AHM, Aletaha D, Bingham CO, Burmester GR, Dougados M, et al. EULAR definition of erosive disease in light of the 2010 ACR/EULAR rheumatoid arthritis classification criteria. Ann Rheum Dis. avr 2013;72(4):479‑81.

[2]Roux C, Gandjbakhch F, Pierreisnard A, Couderc M, Lukas C, Masri R, et al. Optimization of ultrasonographic examination for the diagnosis of erosive Rheumatoid Arthritis in comparison to erosive hand Osteoarthritis. Eur J Radiol. sept 2019;118:10‑8.

Disclosure of Interests:

None declared

Tumour malignancy loss and cell differentiation are associated with induction of gef gene in human melanoma cells

BACKGROUND

Gene therapy is a new method used to induce cancer cell differentiation. Our group previously showed that transfection of the gef gene from Escherichia coli, related to cell-killing functions, may be a novel candidate for cancer gene therapy. Its expression leads to cell cycle arrest unrelated to the triggering of apoptosis in MS-36 melanoma cells.

OBJECTIVES

To determine the basis of the antiproliferative effect of the gef gene in this cell line.

METHODS

Transmission electron microscopy, apoptosis analysis by confocal microscopy, flow cytometry and immunocytochemical analysis were used.

RESULTS

Ultrastructural analysis showed a strikingly different morphology after treatment with dexamethasone and expression of the gef gene, with large accumulations of pigment throughout the cell cytoplasm and presence of melanosomes in different stages of development. High mitochondrial turnover and myeloid bodies, characteristics of neurone cells, were also observed. In addition, both immunocytochemical and indirect immunofluorescence analysis demonstrated a significant decrease in HMB-45, Ki-67 and CD44 antigen expression and an increase in S100 and p53 expression in gef gene-transfected MS-36 melanoma cells that were correlated with the duration of dexamethasone treatment. In the present work, we report that gef gene not only reduces cell proliferation in transfected melanoma MS-36TG cell line but also induces morphological changes clearly indicative of melanoma cell differentiation and a reduction in tumour malignancy.

CONCLUSIONS

These findings support the hypothesis that the gef gene offers a new approach to differentiation therapy in melanoma.

Lateral mobility and anchoring of recombinant GABAA receptors depend on subunit composition

The clustering of type A gamma-aminobutyric acid receptors (GABA(A)R) at discrete and functionally significant domains on the nerve cell surface is an important determinant in the integration of synaptic inputs. To discern the role that the subunits of the GABA(A)R play in determining the receptor's cell surface topography and mobility, the alpha1, beta1, beta3, and gamma2s subunits were transfected into COS7, HEK293, and PC12 cells and the distribution and cell surface mobility of these recombinant receptors were examined. Our results show that alpha1 subunits are retained in the endoplasmic reticulum while beta1 and beta3 subunits are sorted to the plasma membrane where they form clusters. Co-expression and co-assembly of alpha1 and beta3 subunits result in the rescue of intracellular alpha1 subunits, which are transported as alphabeta subunit complexes to the cell surface where they formed clusters. Fluorescence photobleach recovery and single particle tracking of recombinant receptors show that, despite clustering, beta3 subunit homooligomers are mobile within a cell surface domain. Inclusion of alpha1 in beta3 or beta3gamma2s complexes, however, dramatically reduces the receptor's lateral mobility in COS 7 and PC12 cells and anchors GABA(A)Rs on the cell surface, suggesting the formation of a direct link to a component of the cytoskeleton. The mobility of recombinant receptors that include the alpha1 subunit mirrors the mobility of GABA(A)Rs on cell bodies and dendrites of cortical and spinal cord neurons. The results suggest that incorporation of alpha1 subunits give rise to a population of GABA(A)Rs that are immobilized on the cell surface.

Increase in plasma thyrotropin levels in hypothyroid patients during treatment due to a defect in the commercial preparation

Around mid-1995, the Molecular Endocrinology Laboratory of the Regional Hospital (Malaga, Spain) began detecting an increase in TSH levels in the serum of patients under study to control the treatment of hypothyroidism with levothyroxine. Over a period of 5 months, of a total of 467 hypothyroid patients treated with Levothyroid, 53% had TSH levels higher than 6 microU/mL. The reliability of the biochemical results was verified by duplicating 56 randomly chosen samples from all those with high TSH levels and by an external control performed in four different laboratories. The amount of levothyroxine in the tablets was analyzed by RIA, high performance liquid chromatography, and their iodine contents. The lowest levels of levothyroxine found in the 50 micrograms Levothyroid tablets were those determined by RIA, with a mean value of 32.3 micrograms, resulting in a 35.3% loss of activity. The mean value of levothyroxine found in these same tablets by high performance liquid chromatography was 39.3 micrograms, amounting to a 21.3% loss in activity. The iodine showed no significant loss in these tablets, with a mean experimental value of 48 micrograms. The commercial laboratory withdrew lot J from the market, the one in which these deficiencies were found.