Spinal cord syndromes in patients with systemic lupus erythematosus: differentiating lupus myelitis, neuromyelitis optica, and multiple sclerosis.

OBJECTIVE: Non-infectious myelitis in systemic lupus erythematosus (SLE) may be due to SLE myelitis, comorbid multiple sclerosis (MS), or neuromyelitis optica (NMO). We compared characteristics of these three conditions in SLE patients at a large academic institution. METHODS: We searched for neurologic diagnoses of SLE myelitis, NMO myelitis, and MS myelitis among 2297 patients with at least four 1997 American College of Rheumatology revised criteria for SLE between 2000 and 2015. Each subject was reviewed by a neurologist to confirm the underlying neurologic diagnosis. Demographic, clinical, laboratory, and radiographic data were extracted and compared using Fisher's exact test, analysis of variance, and Wilcoxon rank-sum test. RESULTS: Fifteen of the 2297 subjects with SLE (0.7%) met criteria for a spinal cord syndrome: seven had SLE myelitis, three had AQP4 seropositive NMO, and five had MS. The median SLE Disease Activity Index 2000 score at time of neurologic syndrome presentation was higher in SLE myelitis subjects (8, interquartile range (IQR) 7-16) compared with subjects with NMO (6, IQR 0-14) or MS (2, IQR 0-4), p = 0.02. Subjects with SLE myelitis were also more likely to have elevated anti-dsDNA antibodies at presentation (86%) compared with subjects with NMO (33%) or MS (0%), p = 0.03. CONCLUSION: Myelitis occurs rarely among patients with SLE. Compared with subjects with SLE + NMO and subjects with SLE + MS, subjects with SLE myelitis had higher SLE disease activity at presentation.

Arthritis and use of hydroxychloroquine associated with a decreased risk of macrophage activation syndrome among adult patients hospitalized with systemic lupus erythematosus.

Background Macrophage activation syndrome (MAS) is an uncommon but serious complication of systemic lupus erythematosus (SLE). We aimed to identify factors associated with MAS among adult hospitalized SLE patients. Methods Within the Brigham and Women's Hospital (BWH) Lupus Center Registry, we identified adult SLE patients > age 17 who had been hospitalized from 1970 to 2016, with either ferritin > 5000 ng/ml during admission or "macrophage activation syndrome" or "MAS" in discharge summary. We confirmed MAS by physician diagnosis in medical record review. We matched each hospitalized SLE patient with MAS to four SLE patients hospitalized without MAS (by SLE diagnosis date ±1 year). We employed conditional logistic regression models to identify clinical factors associated with MAS among hospitalized SLE patients. Results Among 2094 patients with confirmed SLE, we identified 23 who had a hospitalization with MAS and compared them to 92 hospitalized without MAS. Cases and controls had similar age at SLE diagnosis (29.0 vs. 30.5, p = 0.60), and hospital admission (43.0 vs. 38.3, p = 0.80), proportion female (78% vs. 84%, p = 0.55), and time between SLE diagnosis and hospitalization (1971 vs. 1732 days, p = 0.84). Arthritis (OR 0.04 (95% CI 0.004-0.35)) and hydroxychloroquine use (OR 0.18 (95% CI 0.04-0.72)) on admission were associated with decreased MAS risk. Admission Systemic Lupus Erythematosus Disease Activity Index scores (30 vs. 19, p = 0.002) and lengths of stay (16 days vs. 3 days, p < 0.0001) were much higher among cases. Death during hospitalization was 19% among cases and 3% among controls ( p = 0.03). Conclusions In this case-control study of hospitalized adult SLE patients, arthritis and hydroxychloroquine use at hospital admission were associated with decreased MAS risk. Further studies are needed to validate these factors associated with lowered MAS risk.

Lysophosphatidic acid mimics serum-induced sensitization of cyclic AMP accumulation.

Pretreatment of 1321N1 human astrocytoma cells with serum induces a pronounced increase in subsequent stimulation by forskolin and other agents of intracellular cyclic AMP accumulation, a phenomenon referred to as sensitization (Mol. Pharmacol. 39, 399-406, 1991). Pretreatment of these cells with lysophosphatidic acid induced sensitization to a similar extent as that with serum (approximately fivefold for forskolin stimulation and twofold for isoproterenol and prostaglandin E1 stimulation), with half-maximal effects at approximately 30 nM lysophosphatidic acid. Phosphatidic acid was effective but less potent whereas other lipids were ineffective. Sensitization by serum and by lysophosphatidic acid were almost completely inhibited by pertussis toxin pretreatment and partially inhibited by prolonged phorbol ester exposure to induce protein kinase C down-regulation. Among nine cell lines tested, those that exhibited sensitization with serum showed comparable sensitization with lysophosphatidic acid. The effects of both lysophosphatidic acid and serum were markedly inhibited by treatment with phospholipase B but only minimally altered with phospholipases A2, D, and C. Exposure of cells to phospholipase C alone induced approximately threefold sensitization, but both serum and lysophosphatidic acid were able to induce further three- to fourfold sensitization above that induced by phospholipase C alone. In contrast, the effects of serum and lysophosphatidic acid were not additive with each other. Together these results suggest that lysophosphatidic acid or a closely related compound present in serum is the factor responsible for sensitization of the cyclic AMP pathway.

Antigenic modification, rosette-forming cells, and Salmonella typhimurium resistance in outbred and inbred mice.

To assess the separate contributions of host T cells and the physical state of the antigen in the development of effective. Salmonella resistance, glutaraldehyde-treated and untreated protein- and ribonucleic acid-rich extracts (E-RNA extracts) of virulent Salmonella typhimurium SR-11 or attenuated S. typhimurium RIA were used to immunize Salmonella-resistant Salmonella-susceptible strains of mice for the purpose of determining whether antigen-specific T-cell or B-cell responses were formed and, if so, which responses predominated. The resistance imparted to each mouse strain after vaccination with S. typhimurium RIA was used as the standard for comparison. The inbred mouse strains C57BL/6 and DBA/2 and their F(1) hybrid (strain BDF(1)), outbred ICR Swiss mice, and endotoxin-resistant C3H/HeJ mice were examined for the capacity to develop resistance to lethal Salmonella infections, as well as the ability to generate antigen-reactive T cells. Only the BDF(1), C3H/HeJ, and ICR Swiss mice were able to develop resistance to challenge infections mediated by the virulent SR-11 strain of S. typhimurium after vaccination with the living, attenuated RIA strain of S. typhimurium or immunization with E-RNA extracts. We developed an assay to identify the antigen-reactive rosette-forming lymphocytes present in lymph nodes and spleens of immunized mice. Levels of 0.2% or higher of theta antigen-bearing, antigen-reactive rosette-forming cells were found in the lymph nodes or spleens or both of only the BDF(1), C3H/HeJ, and ICR Swiss mice (i.e., in the "Salmonella responder" strains). Mouse strains C57BL/6 and DBA/2, which failed to develop resistance to lethal infections after immunization with the S. typhimurium RIA vaccine or with the E-RNA extracts, lacked effective numbers of antitheta antigen-sensitive rosette-forming cells. Modification of the effective E-RNA extracts by polymerization with glutaraldehyde resulted in a marked diminution in their abilities to induce resistance to salmonellosis in the two responder mouse strains tested (BDF(1) and ICR Swiss), even though detectable levels of antibody were induced.

Antigenic modification: its relation to protective host resistance in murine salmonellosis.

Both the physical state of the immunogen and the route of immunization were found to be extremely important in inducing effective host resistance against salmonellosis.