Background: Pediatric lupus nephritis (LN) is one of the most serious manifestations of systemic lupus erythematosus (SLE) in children, determining the outcomes of the disease. There are no standardized treatment protocols for pediatric LN, and the role of biologics has not yet been conclusively defined. Objectives: analyze the safety and efficacy of rituximab biosimilar BCD020 in pediatric patients with lupus nephritis. Methods: in a retrospective cohort study, the data from the case histories of 25 patients with LN (10 boys and 15 girls) with an onset age of 13 (9–16) years, who failed conventional non-biologic treatment or developed corticosteroid dependence/toxicity, were included. The diagnosis was made using Systemic Lupus International Collaborating Clinics (SLICC) classification criteria. Rituximab biosimilar BCD020 was prescribed in a dosage of 375 mg/m² every week (2–4 infusions) with repeated courses every 6–12 months (2–4 infusions) according to disease activity, B-cell depletion, and IgG levels. The dynamics of clinical and laboratory data, the activity of the disease by SLEDAI, and corticosteroid doses were assessed at the onset and during the rituximab trial. Results: The main patient’s characteristics were: Pre-rituximab non-biologic conventional treatment included: cyclophosphamide 15 (60%), MMF 8 (32%), azathioprine 3 (12%), hydroxychloroquine 12 (48%), and pulse therapy of methylprednisolone followed by oral methylprednisolone 25 (100%). The time before rituximab was 7.0 (3.0–24.0) months, and the whole observation period was 7.0 (0; 24) months. The initial pre-rituximab treatment slightly reduced SLEDAI levels and the proportion of patients with LN. A significant reduction of SLEDAI, the anti-dsDNA level, proteinuria, hematuria, C4 complement, ESR, and the median corticosteroid dose by 80% from the initial value, as well as the proportion of patients without corticosteroids, was observed after rituximab administration. Two deaths were observed due to catastrophic SLE with macrophage activation syndrome, accompanied by a severe infection (invasive aspergillosis, n = 2). Three patients developed serious adverse events: pneumonia (n = 2), transient agranulocytosis (n = 1) after the third rituximab infusion, and meningitis, caused by Listeria monocytosis, after the first rituximab infusion. Eight patients received antibacterial treatment for different respiratory infections without hospital admissions. Conclusions: Rituximab biosimilar BCD020 showed effectiveness in LN, whereas previous non-biologic treatment was insufficiently effective. Randomized controlled trials are required to evaluate the efficacy and safety of rituximab and evaluate the benefits when compared with conventional SLE treatment.

Type 1 interferons (IFN1) are both key molecules of antiviral defense and potent inflammatory mediators. In 2003, increased expression of a variety of interferon 1-regulated genes was observed in a blood cells of patients with systemic lupus erythematosus (SLE). This phenomenon was called the type 1 interferon signature (IFN1-signature). Since then, expression patterns indicating the presence of an IFN1-signature were consistently detected in a range of monogenic and complex autoimmune and autoinflammatory conditions. A quantitative indicator reflecting the degree of hyperactivation of the IFN1 pathway is known as interferon score. This review discusses the possible causes of upregulated expression of interferon 1-induced genes, the laboratory approaches to the interferon score analysis, as well as the practical use of this indicator for the diagnosis of various conditions.

Introduction: Interferon I (IFN I) signaling hyperactivation is considered one of the most important pathogenetic mechanisms in systemic lupus erythematosus (SLE). Early manifestation and more severe SLE courses in children suggest a stronger genetic influence in childhood-onset SLE (cSLE). Aim: To evaluate IFN-I score and SLE-associated genetic variants in cSLE. Material and Methods: 80 patients with cSLE were included in the study. IFN I-score was assessed by real-time PCR quantitation of 5 IFN I-regulated transcripts (IFI44L, IFI44, IFIT3, LY6E, MXA1) in 60 patients. Clinical exome sequencing (CES) was performed in 51 patients. Whole-exome sequencing was performed in 32 patients with negative results of CES. Results: 46/60 patients (77%) had elevated IFN-I scores. Leucopenia and skin involvement were associated with over-expression of IFI44 and IFI44L, while hypocomplementemia—with hyperactivation of IFIT3, LY6E, and MX1. No correlation of IFN-I score with disease activity was found. At least one rare genetic variant, potentially associated with SLE, was found in 29 (56.9%) patients. The frequency of any SLE-genetic variants in patients with increased IFN scores was 84%, in patients with normal IFN scores—33%, and in the group whose IFN score was not assessed was 65% (p = 0.040). The majority of genetic variants (74%) are functionally related to nucleic acid sensing and IFN-signaling. The highest frequency of genetic variants was observed in Sakha patients (9/14; 64.3%); three and two unrelated patients had identical variants in PTPN22 and TREX1 genes, respectively. Conclusions: More than half of patients with childhood-onset SLE have rare variants in SLE-associated genes. The IFN-I score could be considered a tool for the selection of patients for further genetic assessment in whom monogenic lupus is suspected.

Introduction: Aicardi-Gouteres syndrome (AGS) is a monogenic interferonopathy characterized by early onset, dysregulation of skin (chilblain lesions), brain, and immune systems (fever, hepatomegaly, glaucoma, arthritis, myositis, and autoimmune activity). The disease looks like TORCH (Toxoplasmosis, Others, Rubella, Cytomegalovirus, Herpes) infection with early-onset encephalopathy resulting in severe neuropsychological disability. Case description: A six-year-old girl has been suffering from generalized seizures, fever episodes, severe psychomotor development delay, and spastic tetraparesis since the first year of her life. Her two elder brothers died at a young age from suspected infantile cerebral palsy (ICP). Other siblings (younger brother and two elder sisters) are as healthy as their parents. The girl was diagnosed with juvenile dermatomyositis at 5.5 years. Basal ganglia, periventricular, and cerebellum calcifications; hypoplasia of the corpus callosum; and leukodystrophy were detected on CT. The IFN-I score was 12 times higher than normal. The previously not described nucleotide variant c.434G > C (chr 20:36935104C > G; NM_015474) was detected in exon 4 of the SAMHD1 gene in the homozygous state, leading to amino acid substitution p.R145P. Aicardi-Goutières syndrome 5 was diagnosed. Her treatment included corticosteroids, methotrexate, and tofacitinib 5 mg twice a day and it contributed to health improvements. The following brain CT depicted the previously discovered changes without the sign of calcification spreading. Conclusions: Early diagnosis of AGS is highly important as it allows starting treatment in a timely manner. Timely treatment, in return, can help avoid the development/progression of end-organ damage, including severe neurological complications and early death. It is necessary to spread information about AGS among neurologists, neonatologists, infectious disease specialists, and pediatricians. A multidisciplinary team approach is required.

Systemic corticosteroids are continued to be administered in juvenile idiopathic arthritis (JIA) patients, especially in systemic JIA (sJIA), despite the ability of biologic therapy. One of the complications of long-term CS treatment is delayed hip arthritis development with risk of secondary hip osteoarthritis formation and total hip arthroplasty (THA).We compared different types of hip joint lesions in JIA, especially, secondary hip osteoarthritis development and THA rates in systemic and non-systemic JIA, and evaluate systemic corticosteroids contribution to those complications.The study included 753 JIA patients. They were divided into 2 groups: patients with sJIA and non-systemic JIA (nsJIA). Clinical and demographic characteristics, CS treatment regimens were compared.Results. Hip arthritis was found equally often in both groups, but both secondary hip osteoarthritis (19% vs 5,3%) and THA (8.6% vs 1.6%) prevailed in the sJIA. Patients with sJIA had delayed hip involvement (57.9% vs 30.6%; p=0.019), earlier secondary hip osteoarthritis development (4.5 vs 5.1 years after the JIA onset) with younger age of secondary hip osteoarthritis achievement (13.7 vs 15.2 years; р=0.045), they also had higher inflammatory activity, greater systemic corticosteroids administration (94.8% vs 56.1%; р=0.0000001) and higher cumulative systemic corticosteroids dose (3085 mg vs 2000 mg; p=0,005). More than half patients (56.1%) with nsJIA had systemic corticosteroids treatment and impaired calcium-phosphorus metabolism.Conclusion. Systemic corticosteroid treatment and delayed hip involvement are independent predictors of secondary hip osteoarthritis in all JIA categories. Calcium and phosphate metabolism disturbances are additional predictor for secondary hip osteoarthritis in non-systemic JIA categories

Systemic lupus erythematosus is an immunopathological disease which is characterized by a poor prognosis. Biologics applied in the disease treatment allow reducing the corticosteroid toxicity and controlling the disease.Purpose. To evaluate the efficacy and safety of rituximab therapy in children with systemic lupus erythematosus.Material and methods. The retrospective study included data of 48 patients with systemic lupus erythematosus treated with rituximab. Systemic lupus erythematosus was diagnosed based on the SLICC classification criteria. Patients were assessed at baseline disease status, at the time of rituximab initiation and follow-up. The indications for the rituximab were: lupus nephritis, CNS involvement, and hematological involvement resistant to the standard therapy, and in cases of severe corticosteroid toxicity.Results. During rituximab therapy the significant decrease of the SELENA–SLEDAI activity index was observed. There was a significant decrease of the level of antibodies against dsDNA, normalization of the levels of hemoglobin, ESR, complement C4. The proportion of patients with cytopenia decreased up to their complete absence in patients receiving therapy for three years. The number of patients with active lupus nephritis decreased from 16 at the time of rituximab initiation to 1 after 3 years of therapy. Significant dynamics of proteinuria and hematuria was noted, except for 1 patient. The daily dose of corticosteroids was reduced by 90% from baseline in patients treated for 3 years. Serious adverse events included three deaths in patients with high systemic lupus erythematosus activity with uncontrolled macrophage activation syndrome associated with infections. Various infectious complications, hypogammaglobulinemia, which required replacement therapy with intravenous immunoglobulin, were also recorded.Conclusion. Rituximab can be considered as an option for the treatment of severe forms of systemic lupus erythematosus which are resistant to standard therapy. Further studies are required to evaluate efficacy and safety.