Clinicopathological characteristics of familial SLE patients with lupus nephritis

Lupus Nephritis Risk Factors and Biomarkers: An Update

Lupus nephritis (LN) represents the most severe organ manifestation of systemic lupus erythematosus (SLE) in terms of morbidity and mortality. To reduce these risks, tremendous efforts have been made in the last decade to characterize the different steps of the disease and to develop biomarkers in order to better (i) unravel the pre-SLE stage (e.g., anti-nuclear antibodies and interferon signature); (ii) more timely initiation of therapy by improving early and accurate LN diagnosis (e.g., pathologic classification was revised); (iii) monitor disease activity and therapeutic response (e.g., recommendation to re-biopsy, new urinary biomarkers); (iv) prevent disease flares (e.g., serologic and urinary biomarkers); (v) mitigate the deterioration in the renal function; and (vi) reduce side effects with new therapeutic guidelines and novel therapies. However, progress is poor in terms of improvement with early death attributed to active SLE or infections, while later deaths are related to the chronicity of the disease and the use of toxic therapies. Consequently, an individualized treat-to-target strategy is mandatory, and for that, there is an unmet need to develop a set of accurate biomarkers to be used as the standard of care and adapted to each stage of the disease.

Identification of a novel mutation in complement receptor 2 in Chinese familial systemic lupus erythematosus

Objectives

This study aims to analyze the relationship between complement receptor 2 (CR2) gene mutation and the clinical phenotype in Chinese familial systemic lupus erythematosus (SLE).

Patients and methods

A total of one Chinese familial SLE patients (median age: 30.25 years; range, 22 to 49 years) were included between January 2017 and December 2018. The clinical features and diagnoses of familial SLE patients were analyzed using whole-exome sequencing (WES) of genomic deoxyribonucleic acid (DNA) samples. Sanger sequencing was used to verify candidate mutations detected in the examined family.

Results

The mother and her three daughters were diagnosed with SLE. The clinical characteristics showed that the patient and her mother were diagnosed with lupus nephritis. The eldest daughter had decreased renal function and lower serum albumin levels. Immunological index analysis showed that all four patients were positive for anti-SSA and antinuclear antibody (ANA), but that only the second daughter was positive for anti-double-stranded DNA (dsDNA). Complement 3 (C3) was significantly decreased in all patients, while evaluation of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) showed that the second and third daughters had mild active SLE. The mother and eldest daughter were treated with prednisolone combined with cyclophosphamide, while the other two daughters were treated with prednisolone alone. The WES and Sanger sequencing analyses revealed an unreported missense T>C mutation c.2804 in the 15^th exon of the CR gene in all four patients.

Conclusion

We identified a novel c.2804 (exon 15) T>C mutation in the CR gene of Chinese familial SLE. This mutation was previously reported, suggesting that the CR gene c.2804 (exon 15) T>C mutation is the probable cause of SLE in this family.

Systemic lupus erythematosus with and without a family history: a meta-analysis

Objective The objective of this paper is to investigate the association of clinical manifestations and laboratory parameters between familial systemic lupus erythematosus (SLE) and sporadic SLE. Methods All relevant literature was retrieved from the PubMed, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI) databases. The qualities of these studies were evaluated using a modified version of the Newcastle-Ottawa scale. The characteristics and clinical manifestations of involved individuals were extracted from each study. Pooled odds ratio (OR) was calculated using the random effects-method, and the heterogeneity between studies was quantified using the I² statistic. Results Of 330 studies identified by the search strategy, six were included in this review. In total, 733 cases were familial SLE and 1405 were sporadic SLE. Analysis revealed that photosensitivity, nephritis and thrombocytopenia were negatively associated with familial SLE, with OR (95% CI) values of 0.73 (0.60-0.89), 0.72 (0.59-0.88) and 0.75 (0.57-0.98), respectively. Conclusions Photosensitivity, thrombocytopenia and renal involvement could be more common in non-familial SLE, which should be further confirmed by well-designed studies with large populations.

Is familial lupus different from sporadic lupus? Data from LUMINA (LXXIII), a multiethnic US cohort

The aim of this study was to characterize the clinical features of familial lupus, and determine its influence on damage accrual and survival using data from LUMINA, a longitudinal multiethnic US cohort. Familial lupus was defined as patients with a first-degree relative with systemic lupus erythematosus. Relative risks were estimated by logistic regression; odds ratios (ORs) and their 95% confidence intervals (CIs) were the measure of association for familial lupus. Hazard ratios were calculated using Cox proportional hazards adjusted for potential confounders for damage and survival. Of 644 patients, 32 had familial and 612 had sporadic lupus; both groups were of comparable age (~36 years). Patients with familial lupus were, in decreasing order of frequency, siblings, parents and children. In multivariable analyses, mucosal ulcers (OR = 1.92, 95% CI 0.65-5.70), mitral valve prolapse (OR = 1.74, 95% CI 0.50-6.10), cerebrovascular disease (OR = 4.18, 95% CI 0.98-17.76) and oral contraceptive use (ever/never; OR = 2.51, 95% CI 0.88-7.19) were more likely in familial lupus, but a history of low platelet count (<150,000/mm(3); OR=0.31, 95% CI 0.08-1.17) and pulmonary disease activity (OR=0.39, 95% CI 0.14-1.20) were less likely. However, none of these associations reached statistical significance. Familial lupus was not significantly associated with a shorter time to either damage accrual or death (HR = 0.77, 95% CI 0.37-1.59, p = 0.4746 and HR = 0.20, 95% CI 0.03-1.47, p = 0.2020, respectively). We conclude that although some clinical differences were observed between patients with familial and sporadic lupus, familial lupus was not associated with a significantly greater disease burden (damage, survival) than sporadic lupus.