Double-Negative T (DNT) Cells in Patients with Systemic Lupus Erythematosus.

Double-negative T (DNT) cells are a rare and unconventional T-lymphocyte subpopulation lacking both CD4 and CD8 markers. Their immunopathological roles and clinical relevance have yet to be elucidated. Beyond autoimmune lymphoproliferative syndrome (ALPS), these cells may also play a role in rheumatic disorders, including systemic lupus erythematosus (SLE); indeed, these two diseases share several autoimmune manifestations (including nephritis). Moreover, one of the main experimental murine models used to investigate lupus, namely the MRL/lpr mouse, is characterized by an expansion of DNT cells, which can support the production of pathogenic autoantibodies and/or modulate the immune response in this context. However, lupus murine models are not completely consistent with their human SLE counterpart, of course. In this mini review, we summarize and analyze the most relevant clinical studies investigating the DNT cell population in SLE patients. Overall, based on the present literature review and analysis, DNT cell homeostasis seems to be altered in patients with SLE. Indeed, most of the available clinical studies (which include both adults and children) reported an increased DNT cell percentage in SLE patients, especially during the active phases, even though no clear correlation with disease activity and/or inflammatory parameters has been clearly established. Well-designed, standardized, and longitudinal clinical studies focused on DNT cell population are needed, in order to further elucidate the actual contribution of these cells in SLE pathogenesis and their interactions with other immune cells (also implicated and/or altered in SLE, such as basophils), and clarify whether their expansion and/or immunophenotypic aspects may have any immunopathological relevance (and, then, represent potential disease markers and, in perspective, even therapeutic targets) or are just an unspecific epiphenomenon of autoimmunity.

Comparison between SARS-CoV-2 positive and negative pneumonia in children: A retrospective analysis at the beginning of the pandemic.

BACKGROUND: Even though coronavirus 2019 disease (COVID-19) clinical course in children is much milder than in adults, pneumonia can occur in the pediatric population as well. Here, we reported a single-center pediatric case series of COVID-19 from Kazakhstan during the first wave of pandemic. AIM: To analyze the main clinical and laboratory aspects in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive and negative children diagnosed with pneumonia. METHODS: This is a retrospective analysis of 54 children, who were medically assessed as close contacts of COVID-19 adults in their family setting, between June and September 2020. These children were all hospitalized: We compared the clinical and laboratory characteristics of children affected with pneumonia in the presence (group 1) or absence (group 2) of SARS-CoV-2 infection. RESULTS: Overall, the main clinical manifestations at the admission were fever, cough, loss of appetite, fatigue/weakness, nasal congestion and/or rhinorrhea, and dyspnea. Based on the SARS-CoV-2 polymerase chain reaction (PCR) test, 24 positive children with pneumonia (group 1) and 20 negative children with pneumonia (group 2) were identified; 10 positive children did not show any radiological findings of pneumonia. No significant differences were found between the two pneumonia study groups for any clinical and laboratory parameters, except for C-reactive protein (CRP). Of course, both pneumonia groups showed increased CRP values; however, the COVID-19 pneumonia group 1 showed a significantly higher increase of CRP compared to group 2. CONCLUSION: In our case series of children assessed for SARS-CoV-2 infection based on contact tracing, the acute inflammatory response and, in detail, CRP increase resulted to be more pronounced in COVID-19 children with pneumonia than in children with SARS-CoV-2-unrelated pneumonia. However, because of multiple limitations of this study, larger, controlled and more complete clinical studies are needed to verify this finding.

Date of birth and hay fever risk in children and adolescents of Kazakhstan.

UNLABELLED: Introduction the first months of life are the most vulnerable period in allergic disease development and it is not clear enough whether inhalant pollen allergen exposure predisposes the risk of consequent allergic reactions. OBJECTIVE: To study the clinical and epidemiological criteria of hay fever with special emphasis on investigation of the relationship between the date of birth and seasonal allergic rhinitis development in children and adolescents in Kazakhstan. METHODS: The prospective hospital based study was conducted during pollen season from the beginning of May to the end of October in two consequent years 2010 and 2011. 184 children and adolescents at the age of 1--17 years underwent consultations and skin prick tests in the allergological center "Umit" (Astana, Kazakhstan). Special allergological questionnaires were developed and adapted for local residents. The assessment of symptoms severity was performed using a scoring system. Skin prick tests were performed in 112 patients. The number of patients was explained by the age limitations. Correlation analysis between skin prick test results and the month of birth were performed. RESULTS: It was found that in summer months there were the highest number of patients with seasonal allergic rhinitis 68 (36.9%), followed by spring 44 (23.9%), then autumn 37 (20.1%) and the lowest percent of patients 35 (19.1%) was born in winter. Rhinoconjunctival syndrome was diagnosed in 180 (97.8%) patients, pollen induced bronchial asthma in 76 (41.3%) and pollen induced urticaria in 35 (19.0%) patients. Mono sensitization among Kazakhstan children and adolescents was determined only to several species of the plants, mainly to Artemisia Absinthium (68.2%) and Sunflower (25.7%), whereas multiple sensitization to the mix of weeds was determined in 75 (66.9%) patients, to the mix of meadow grass in 33 (29.4%), mix of meadow grass+mix of weeds in 25 (22.3%) and mix of trees in 9 (7.1%) patients. The mean of symptoms severity of total scoring (24) was 15.5. The mean of IgE level in blood tests was 323.2IU/ml. CONCLUSIONS: Our results proved that first months of life are the crucial period and inhalant pollen allergen exposure, particularly to the weeds pollen, predisposes the risk of consequent allergic reactions development in children and adolescents in Kazakhstan. This fact may predetermine the risk of consequent allergic reactions development and the awareness of patients about it helps to prevent following severe clinical manifestations.

The peculiarities of different types of chronic rhinitis in children and adolescents in Kazakhstan.

BACKGROUND: The aim was to study the peculiarities of differential diagnosis, prevention and treatment of different forms of rhinitis in Kazakhstan children and adolescents. METHODS: 124 children and adolescents aged 1-17 years were randomly enrolled in our hospital based study in 2010 and 2011. Skin prick tests and total serum IgE level were assessed in all allergic patients. Subcutaneous specific immunotherapy was performed in 57 (70.3%) allergic patients. For the treatment of the developed rhinitis, we used intranasal glucocorticosteroids in all 47 (37.9%) patients with rhinitis medicamentosa. RESULTS: Allergic rhinitis was diagnosed in 81 (65.3%), infectious rhinitis in 43 (34.7%) and rhinitis medicamentosa in 47 (37.9%) cases. High mono sensitization was mainly to Artemisia Absinthium 55 (67.9%) and Sunflower 20 (24.7%) species, whereas multiple sensitization was caused by the mix of weeds in 55 (67.9%) and the mix of meadow grass in 31 (38.3%). The mean IgE level was 323.2±264.9SD. Only 5 (17.2%) patients with specific immunotherapy developed rhinitis medicamentosa. 35 (74.5%) patients treated by nasal glucocorticosteroids stopped taking the decongestants. CONCLUSIONS: The incidence of rhinitis medicamentosa depends on duration of decongestants use. Specific immunotherapy is recommended for the prevention of rhinitis medicamentosa in patients suffering from allergic rhinitis, whereas intranasal glucocorticosteroids are the most appropriate for the treatment regardless initial cause of rhinitis development.