Latent tuberculosis infection (LTBI) represents a major global health concern as it constitutes the principal reservoir for future tuberculosis (TB) disease. Its identification is particularly important in Bacille Calmette–Guérin (BCG)-vaccinated populations, where cross-reactivity of purified protein derivative limits the specificity of the tuberculin skin test and hampers targeted preventive therapy. Early Mycobacterium tuberculosis antigens encoded within the RD1 region, especially ESAT-6, CFP-10 and TB7.7, have enabled the development of antigen-specific interferon-gamma release assays (IGRAs) and recombinant skin tests with improved BCG-independent specificity. This narrative review integrates and critically appraises current evidence on the immunobiological properties of early and latency-associated antigens, the cellular mechanisms underlying T-cell-dependent immune reactivity, and the diagnostic performance of IGRAs and ESAT-6/CFP-10-based skin tests, rather than merely summarizing individual studies. Although these platforms rely on different assay principles (in vitro cytokine release versus in vivo delayed-type hypersensitivity), both measure antigen-specific T-cell memory and do not define the biological stage of infection or reliably distinguish latent from incipient or active TB. Across most adult populations, IGRAs demonstrate high specificity and acceptable sensitivity, whereas reduced sensitivity and higher rates of indeterminate results are observed in young children and immunocompromised individuals. ESAT-6/CFP-10-based skin tests show diagnostic accuracy comparable to IGRAs and may offer operational advantages in resource-limited settings. Latency-associated antigens and host biomarkers such as IP-10, together with multi-analyte immune signatures, represent promising avenues for improving diagnostic sensitivity and prognostic stratification but currently lack sufficient validation for routine clinical use. Overall, RD1-encoded antigens remain central to LTBI immunodiagnosis, while future research should focus on developing stage-resolving and prognostic biomarkers, optimized antigen panels, and standardized interpretive frameworks.

Antibiotic resistance is a major global health concern, and inappropriate antibiotic use contributes significantly to the development of resistance in pathogens. Bacteroides fragilis, an anaerobic bacterium, is commonly treated with β-lactam antibiotics like meropenem. B. fragilis possesses various antibiotic resistance mechanisms, including enzymatic modification of antibiotics, efflux systems, and reduction of cell membrane permeability. The primary mechanism of carbapenem resistance in B. fragilis is linked to the production of a metallo-β-lactamase encoded by the cfiA gene. However, this gene is frequently inactive and requires activation by insertion elements. The study aimed to explore the expression of specific genes in B. fragilis associated with different metabolic pathways in response to exposure to sub-inhibitory concentrations of meropenem. The study used B. fragilis strain BFR KZ01, obtained from a patient with appendicitis and peritonitis. Serial exposure to meropenem was conducted, and gene expression was analyzed using quantitative RT-PCR. Significant and long-lasting alterations in gene expression patterns were observed in B. fragilis following exposure to meropenem, even after removal of the antibiotic. Genes such as cfiA, oxyR, and Ddl showed heightened expression levels even after discontinuation of meropenem. The study discussed the implications of gene expression changes induced by meropenem exposure, highlighting the role of oxidative stress response (oxyR), D-Ala-D-Ala ligase (Ddl), and carbapenemase (cfiA) genes in antibiotic resistance mechanisms. The study concluded that exposure to meropenem induced lasting alterations in gene expression in B. fragilis, contributing to antibiotic resistance. Understanding these mechanisms is crucial for developing strategies to combat antibiotic resistance.

Acute gastroenteritis (AGE) remains one of the leading causes of infectious morbidity among children. The aim of this study was to conduct a comprehensive analysis of epidemiological trends, limitations of laboratory diagnostics, and antimicrobial resistance patterns of AGE pathogens among children in Kazakhstan during 2018–2025. A retrospective analysis of official statistical data, clinical and laboratory indicators, and microbiological study results from 2018 to 2025 was performed. Trends in bacterial and viral AGE, age-specific disease distribution, the impact of the COVID-19 pandemic, and antimicrobial resistance profiles of clinically significant enterobacteria were evaluated. A decline in the incidence of bacterial AGE, including shigellosis and salmonellosis, was identified, accompanied by an increase in cases of unspecified etiology. The highest involvement in the epidemic process of viral diarrheal diseases was observed among children under 14 years of age. Significant fluctuations in incidence rates were recorded during the post-pandemic period. The COVID-19 pandemic affected the epidemiology of intestinal infections and was associated with gastrointestinal manifestations in children. Analysis of antimicrobial resistance among opportunistic enterobacteria (Klebsiella pneumoniae, Proteus mirabilis, ESBL-producing Escherichia Coli, and Pseudomonas aeruginosa) demonstrated high levels of resistance to ampicillin and third-generation cephalosporins. Limitations in laboratory diagnostics and epidemiological surveillance were identified, related to the low proportion of etiologically confirmed cases and inadequate registration of viral diarrheal diseases. Acute gastroenteritis in children remains a significant public health concern in Kazakhstan. Improvement of laboratory diagnostics through the implementation of molecular genetic methods, strengthening epidemiological surveillance of bacterial and viral intestinal infections, and expanding antimicrobial resistance monitoring are necessary to enhance treatment effectiveness and prevent complications. Keywords: acute gastroenterocolitis, children, intestinal infections, diarrhea, antibiotic resistance.

Relevance: Bacterial meningitis (BM) remains a significant cause of neurological complications and high mortality among children. Aim: to study the clinical features of BM in children to optimize the diagnosis and etiopathogenetic therapy. Methods: The object of the study is children diagnosed with meningitis, treated at the Multidisciplinary City Children's Hospital No. 3 in Astana, for the period from 2015 to 2023. Study design: prospective, control - case. Methods included clinical examination, complete blood count, cerebrospinal fluid test, CT and brain MRI. Descriptive statistics and Pearson's method were used for statistical processing. Results: Introduction of the PCV13 vaccine led to a fourfold decrease in the incidence of pneumococcal meningitis, while cases of meningococcal meningitis declined 1.6 times from 2014 to 2023. The main clinical manifestations in children with BM included high fever (80–90% of patients, with febrile temperatures ranging from 38.7°C to 39.9°C), neurological deficits, and complications: seizures and cognitive impairment developed in 50% of children. Hypertensive syndrome was observed in 81.8% of children with pneumococcal meningitis (PM), and in 55.6% of meningococcal meningitis (MM) cases among children under one year old. Pneumococcal CNS involvement was characterized by focal symptoms in 45.5% of young children, while such changes were statistically significantly lower in MM cases—threefold less (16.7%, p≤0.001). Spearman’s correlation analysis in the PM group showed a strong direct positive relationship between the following variables: delayed medical consultation and hospital stay duration (r=0.7; p≤0.001), delayed diagnosis and hospital stay duration (r=0.7; p≤0.001). Conclusion: PCV13 vaccination has significantly reduced the incidence of pneumococcal meningitis, which presents most severely, with early neurological complications in 41.5% of cases, cerebral edema in 90.9% of infants, and hypertensive syndrome in 81.8%. Early diagnosis and timely treatment contribute to the prevention of both early and late neurological complications. Актуальность: Бактериальные менингиты (БМ) остаются значимой причиной неврологических осложнений и высокой смертности среди детей. Цель исследования: изучение клинических особенностей БМ у детей для оптимизации диагностики и этиопатогенетической терапии. Методы: Объект исследования - дети с диагнозом "менингит", пролеченные в Многопрофильной городской детской больнице №3 в г.Астана, за период с 2015 по 2023 гг. Дизайн исследования: проспективный, контроль – случай. Методы включали клинический осмотр, общий анализ крови, анализ спинномозговой жидкости, КТ и МРТ головного мозга. Для статистической обработки использовались описательная статистика и метод Пирсона. Результаты: Введение вакцины ПКВ13 привело к четырехкратному снижению заболеваемости пневмококковым менингитом, в то время как случаи менингококкового менингита уменьшились в 1,6 раз с 2014 по 2023 годы. Основные клинические проявления у детей с БМ включали высокую температуру (80-90% пациентов, с фебрильной температурой от 38,7°С до 39,9°С), неврологические дефициты и осложнения: судороги и когнитивные нарушения–развивались у 50% детей. Гипертензионный синдром наблюдали в 81,8 % случаях в группе детей с ПМ, в 55,6% случаях при ММ у детей до 1 года. Пневмококковое поражение ЦНС характеризовалось развитием очаговой симптоматики в 45,5% случаев у детей раннего возраста, при ММ данные изменения зарегистрированы статистически достоверно меньше в 3 раза (16,7% р≤0,001). Корреляционный анализ по методу Спирмена в группе детей с ПМ продемонстрировала сильную прямую положительную связь между показателями: поздней обращаемости и количеством койко-дней (r=0,7;р≤0,001), поздней диагностикой и количеством койко-дней (r=0,7;р≤0,001). Заключение: Вакцинация ПКВ13 привела к значительному снижению заболеваемости пневмококковым менингитом, который протекает наиболее тяжелее с ранними неврологическими осложнениями в 41,5% случаев, отеком головного мозга у детей первого года жизни в 90,9%, гипертензионным синдромом в 81,8%. Ранняя диагностика и своевременное лечение способствуют предотвращению ранних и поздних неврологических осложнений. Өзектілігі: Бактериялық...