Childhood-Onset Lupus Nephritis in the Childhood Arthritis and Rheumatology Research Alliance Registry: Short-Term Kidney Status and Variation in Care

OBJECTIVE

The goal was to characterize short-term kidney status and describe variation in early care utilization in a multicenter cohort of patients with childhood-onset systemic lupus erythematosus (cSLE) and nephritis.

METHODS

We analyzed previously collected prospective data from North American patients with cSLE with kidney biopsy-proven nephritis enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from March 2017 through December 2019. We determined the proportion of patients with abnormal kidney status at the most recent registry visit and applied generalized linear mixed models to identify associated factors. We also calculated frequency of medication use, both during induction and ever recorded.

RESULTS

We identified 222 patients with kidney biopsy-proven nephritis, with 64% class III/IV nephritis on initial biopsy. At the most recent registry visit at median (interquartile range) of 17 (8-29) months from initial kidney biopsy, 58 of 106 patients (55%) with available data had abnormal kidney status. This finding was associated with male sex (odds ratio [OR] 3.88, 95% confidence interval [95% CI] 1.21-12.46) and age at cSLE diagnosis (OR 1.23, 95% CI 1.01-1.49). Patients with class IV nephritis were more likely than class III to receive cyclophosphamide and rituximab during induction. There was substantial variation in mycophenolate, cyclophosphamide, and rituximab ever use patterns across rheumatology centers.

CONCLUSION

In this cohort with predominately class III/IV nephritis, male sex and older age at cSLE diagnosis were associated with abnormal short-term kidney status. We also observed substantial variation in contemporary medication use for pediatric lupus nephritis between pediatric rheumatology centers. Additional studies are needed to better understand the impact of this variation on long-term kidney outcomes.

Intraarticular steroids as DMARD-sparing agents for juvenile idiopathic arthritis flares: Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) who achieve a drug free remission often experience a flare of their disease requiring either intraarticular steroids (IAS) or systemic treatment with disease modifying anti-rheumatic drugs (DMARDs). IAS offer an opportunity to recapture disease control and avoid exposure to side effects from systemic immunosuppression. We examined a cohort of patients treated with IAS after drug free remission and report the probability of restarting systemic treatment within 12 months.

METHODS

We analyzed a cohort of patients from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry who received IAS for a flare after a period of drug free remission. Historical factors and clinical characteristics and of the patients including data obtained at the time of treatment were analyzed.

RESULTS

We identified 46 patients who met the inclusion criteria. Of those with follow up data available 49% had restarted systemic treatment 6 months after IAS injection and 70% had restarted systemic treatment at 12 months. The proportion of patients with prior use of a biologic DMARD was the only factor that differed between patients who restarted systemic treatment those who did not, both at 6 months (79% vs 35%, p < 0.01) and 12 months (81% vs 33%, p < 0.05).

CONCLUSION

While IAS are an option for all patients who flare after drug free remission, it may not prevent the need to restart systemic treatment. Prior use of a biologic DMARD may predict lack of success for IAS. Those who previously received methotrexate only, on the other hand, are excellent candidates for IAS.

Social determinants of health influence disease activity and functional disability in Polyarticular Juvenile Idiopathic Arthritis

BACKGROUND

Social determinants of health (SDH) greatly influence outcomes during the first year of treatment in rheumatoid arthritis, a disease similar to polyarticular juvenile idiopathic arthritis (pJIA). We investigated the correlation of community poverty level and other SDH with the persistence of moderate to severe disease activity and functional disability over the first year of treatment in pJIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance Registry.

METHODS

In this cohort study, unadjusted and adjusted generalized linear mixed effects models analyzed the effect of community poverty and other SDH on disease activity, using the clinical Juvenile Arthritis Disease Activity Score-10, and disability, using the Child Health Assessment Questionnaire, measured at baseline, 6, and 12 months.

RESULTS

One thousand six hundred eighty-four patients were identified. High community poverty (≥20% living below the federal poverty level) was associated with increased odds of functional disability (OR 1.82, 95% CI 1.28-2.60) but was not statistically significant after adjustment (aOR 1.23, 95% CI 0.81-1.86) and was not associated with increased disease activity. Non-white race/ethnicity was associated with higher disease activity (aOR 2.48, 95% CI: 1.41-4.36). Lower self-reported household income was associated with higher disease activity and persistent functional disability. Public insurance (aOR 1.56, 95% CI 1.06-2.29) and low family education (aOR 1.89, 95% CI 1.14-3.12) was associated with persistent functional disability.

CONCLUSION

High community poverty level was associated with persistent functional disability in unadjusted analysis but not with persistent moderate to high disease activity. Race/ethnicity and other SDH were associated with persistent disease activity and functional disability.

Regional differences in temporomandibular joint inflammation in patients with juvenile idiopathic arthritis: a dynamic post-contrast magnetic resonance imaging study

The purpose was to determine whether there are regional differences in temporomandibular joint (TMJ) inflammation in patients with juvenile idiopathic arthritis (JIA). This was a retrospective study of all patients with dynamic, contrast-enhanced magnetic resonance imaging through the TMJs at Massachusetts General Hospital between January 2015 and July 2016. The patient cohort included those with a history of JIA and control patients who underwent MRI for other routine clinical purposes. TMJ inflammation was quantified as the difference between post-gadolinium and pre-gadolinium articular T1 signal intensity normalized to post-gadolinium signal intensity of the longus capitis muscle. TMJ enhancement profiles were generated for the lateral, central, and medial portions of the TMJ. Regional differences in TMJ enhancement were investigated using basic descriptive statistics. Medial edge enhancement of the TMJs was highest in symptomatic JIA joints, followed by asymptomatic JIA, then control joints. Medial edge enhancement was a significant discriminator between symptomatic JIA TMJs and control joints (P = 0.0001), between symptomatic and asymptomatic JIA TMJs (P = 0.0003), and between asymptomatic JIA TMJs and controls (P = 0.0019). A shift in distribution of TMJ enhancement towards the medial edge that was seen uniquely in both asymptomatic and symptomatic JIA TMJs compared to control joints was found. This suggests a pattern of worsening medial edge inflammation with disease.

Optimization of Quantitative Dynamic Postgadolinium MRI Technique Using Normalized Ratios for the Evaluation of Temporomandibular Joint Synovitis in Patients with Juvenile Idiopathic Arthritis

BACKGROUND AND PURPOSE

MR imaging has been shown to be useful in the diagnosis of juvenile idiopathic arthritis of the temporomandibular joint. Prior MR imaging approaches have relied mainly on the subjective interpretation of synovial enhancement as a marker for synovial inflammation. Although, more recently, several attempts have been made to quantify synovial enhancement, these methods have not taken into account the dynamic enhancement characteristics of the temporomandibular joint and the effect of sampling time. Our aim was to develop a clinically feasible, reproducible, dynamic, contrast-enhanced MR imaging technique for the quantitative assessment of temporomandibular joint synovitis in patients with juvenile idiopathic arthritis and to study the effect of sampling time on the evaluation of synovitis.

MATERIALS AND METHODS

This was a retrospective study of all patients who had dynamic, contrast-enhanced coronal T1 3T MR imaging through the temporomandibular joint at our institution between January 1, 2015, and July 8, 2016. Patients in this cohort included those with a history of juvenile idiopathic arthritis and control patients who underwent MR imaging for other routine, clinical purposes. Synovial enhancement was calculated for each temporomandibular joint using 3 different types of equations termed normalization ratios. The enhancement profiles generated by each equation were studied to determine which provided the best discrimination between affected and unaffected joints, was the least susceptible to sampling errors, and was the most clinically feasible.

RESULTS

A ratio of synovial enhancement (defined as the difference between the postgadolinium and the pregadolinium T1 signal of the synovium) to the postgadolinium signal of the longus capitis provided the best discrimination between affected and unaffected joints, the least susceptibility to sampling error, and was thought to be the most clinically feasible method of quantification of synovial inflammation. Additional synovial enhancement ratios studied did not provide the same level rates of discrimination between the affected and unaffected joints and were thought to be too temporally variable to provide reliable clinical use.

CONCLUSIONS

We provide a robust, reproducible, dynamic gadolinium-enhanced MR imaging technique for the quantitative assessment of temporomandibular joint synovitis in patients with juvenile idiopathic arthritis.

Dust-free regions around Langmuir probes in complex plasmas under microgravity

Dust-free regions around a Langmuir probe are studied in a complex plasma under microgravity. The dust particles settle in the presheath of the probe, where an equilibrium of the electric field force and the ion-drag force is established. The size and shape of the dust cloud are discussed with simple models. A more sophisticated presheath model is solved numerically to analyze the acting forces and the equilibrium position of the dust. The formation of distinct particle layers in the dust shell can be explained by the force gradients of the effective potential well.

Kinetic measurements of shock wave propagation in a three-dimensional complex (dusty) plasma

"Complex plasmas" consist of electrons, ions, and charged microparticles. The latter are individually observable, allowing kinetic measurements in plasmas. Using a sudden gas pulse, a traveling perturbation was initiated in such a complex plasma and its propagation, acceleration, and steepening-possibly into a shock was followed. The experiment was performed in the PKE-Nefedov laboratory under microgravity conditions on the international space station, i.e., in a complex plasma cloud with very little stored (potential or free) energy and thus free of, e.g., parametric instabilities. The perturbation front remained remarkably smooth, with a microroughness of the order of the interparticle distance. The observations are presented and interpreted.

Decharging of complex plasmas: first kinetic observations

The first experiment on the decharging of a complex plasma in microgravity conditions was conducted. After switching off the rf power, in the afterglow plasma, ions and electrons rapidly recombine and leave a cloud of charged microparticles. Because of microgravity, the particles remain suspended in the experimental chamber for a sufficiently long time, allowing precise measurements of the rest particle charge. A simple theoretical model for the decharging is proposed which agrees quite well with the experiment results and predicts the rest charge at lower gas pressures.

Complex-plasma boundaries

This study deals with the boundary between a normal plasma of ions and electrons, and an adjacent complex plasma of ions, electrons, and microparticles, as found in innumerable examples in nature. Here we show that the matching between the two plasmas involve electrostatic double layers. These double layers explain the sharp boundaries observed in the laboratory and in astrophysics. A modified theory is derived for the double layers that form at the discontinuity between two different complex plasmas and at the point of contact of three complex plasmas. The theory is applied to the first measurements from the Plasma Kristall Experiment (PKE) Nefedov Laboratory in the International Space Station.

Gravity compensation in complex plasmas by application of a temperature gradient

Micron-sized particles are suspended or lifted up in a gas by thermophoresis. This allows the study of many processes occurring in strongly coupled complex plasmas at the kinetic level in a relatively stress-free environment. First results of this study are presented. The technique is also of interest for technological applications.

Measurements of forces acting on suspended microparticles in the void region of a complex plasma

A laboratory experiment has been performed in which a temperature gradient is used to generate a large central void in a rf-generated complex plasma. Through the use of laser flashing techniques, two-dimensional velocity vectors have been obtained from particles falling from the top to the bottom of the void. These particles are used to generate a two-dimensional map of the acceleration, and consequently the net forces, that act upon particles in the void.

Optic neuropathy in children with Lyme disease

Involvement of the optic nerve, either because of inflammation or increased intracranial pressure, is a rare manifestation of Lyme disease. Of the 4 children reported here with optic nerve abnormalities, 2 had decreased vision months after disease onset attributable to optic neuritis, and 1 had headache and diplopia early in the infection because of increased intracranial pressure associated with Lyme meningitis. In these 3 children, optic nerve involvement responded well to intravenous ceftriaxone therapy. The fourth child had headache and visual loss attributable to increased intracranial pressure and perhaps also to optic neuritis. Despite treatment with ceftriaxone and steroids, he had persistent increased intracranial pressure leading to permanent bilateral blindness. Clinicians should be aware that neuro-ophthalmologic involvement of Lyme disease may have significant consequences. If increased intracranial pressure persists despite antibiotic therapy, measures must be taken quickly to reduce the pressure.

Recognition of multiple antibody epitopes throughout Borrelia burgdorferi p66, a candidate adhesin, in patients with early or late manifestations of Lyme disease

Antibody responses to p66, a candidate integrin ligand of Borrelia burgdorferi, were studied in 79 patients with early or late manifestations of Lyme disease. The central portion of p66 was previously shown to contain all of the information required for specific recognition of beta3-chain integrins, but work by others had suggested that the C-terminal portion of the protein contains a single surface-exposed, immunodominant loop. In examining antibody responses to full-length p66 and to three overlapping fragments of the protein, we found that the majority of Lyme disease patients had immunoglobulin M (IgM) and/or IgG responses to p66 and that, particularly early in the disease, epitopes throughout p66 were recognized. Among patients with later manifestations of the illness, antibody responses to the C-terminal portion of the protein were more prominent. These results demonstrate that Lyme disease patient sera recognize epitopes throughout p66.

Three-dimensional strongly coupled plasma crystal under gravity conditions

Experiments were carried out to investigate a three-dimensional (3D) plasma crystal. A method of determining the positions of each individual microparticle has been developed. A crystal volume of about 2x10(4) particles in 19 horizontal planes was analyzed. Direct imaging and the 3D pair correlation function show that "domains" of fcc and hcp lattices coexist in the crystal. Other structures, in particular, the theoretically predicted bcc lattice, were not observed.

Production of interleukin-1 and tumor necrosis factor by human peripheral monocytes activated by periodontal bacteria and extracted lipopolysaccharides

Whole Gram-negative bacteria associated with juvenile and adult periodontitis, and their respective extracted lipopolysaccharides (LPS), were tested for the ability to activate quiescent human peripheral blood monocytes. All pathogenic Gram-negative bacteria and all LPS tested were able to induce the production of significant amounts of IL-1 and TNF, monokines known to induce osteoclastic bone resorption. Haemophilus segnis, which has not been associated with any form of periodontal disease, did not activate monocytes. Purified LPS from Actinobacillus actinomycetemcomitans Y4 was able to elicit IL-1 and TNF release at a threshold concentration of 1-10 ng/mL. To examine the mechanism whereby whole bacteria activated monocytes, we added polymixin B in culture with glutaraldehyde-fixed bacteria to bind LPS. This resulted in the abrogation of IL-1 and TNF production. To compare the effects of Gram-positive oral bacteria on monocytes, we also tested Staphylococcus epidermidis and the Gram-positive amphipathic equivalent of LPS, lipoteichoic acid (LTA) extracted from Staphylococcus aureus bacteria. Whereas whole Gram-positive bacteria had no stimulatory effect on monocytes, LTA induced IL-1 and TNF production at a concentration range equivalent to that of the LPS. These results indicate that monocytes are activated by free LPS or LPS bound to Gram-negative pathogenic periodontal bacteria to produce monokines which may contribute to the destruction of periodontal bone.