Background: Biotinidase deficiency is an autosomal recessive disorder of biotin metabolism that can be effectively managed when detected early through newborn screening. Biotinidase activity is influenced by neonatal and preanalytical factors, which may affect the interpretation of screening results. Following the introduction of biotinidase deficiency screening in Mongolia in 2025–2026, population-specific data are needed to support accurate screening interpretation. Aim: To determine the distribution and percentile values of biotinidase activity in Mongolian newborns and evaluate associated neonatal and preanalytical factors. Materials and Methods: This analytical cross-sectional study included 6,764 newborns from 12 healthcare facilities in Mongolia between August 2025 and May 2026. After excluding initial screen-positive samples and those with transport times exceeding 30 days, 6,258 newborns were included in the primary analysis. Biotinidase activity was measured in dried blood spots using the Neonatal Biotinidase 3018-0010 kit and VICTOR2D analyzer. Percentile curves by gestational age and birth weight were smoothed using LOWESS. Group differences and associations were assessed using Welch ANOVA and Pearson correlation, respectively. Result: Among 6,258 newborns, mean biotinidase activity was 133.3±32.6 U, with a median of 130.2 U and a P2.5-P97.5 interval of 78.4-206.6 U. Median activity tended to increase with gestational age and birth weight, while the smoothed percentile curves remained above the 58.5 U screening cutoff. Mean activity increased from 124.4±34.1 U in samples collected before 24 hours to 149.9±44.5 U in those collected after 96 hours (p<0.001). Activity showed weak positive correlations with gestational age (r=0.042, p=0.001), birth weight (r=0.114, p<0.001), and body length (r=0.102, p<0.001), but negative correlations with time from sample collection to laboratory receipt (r=−0.327, p<0.001) and from laboratory receipt to testing (r=−0.154, p<0.001). Conclusion Population-specific percentile values for biotinidase activity were established in a large sample of Mongolian newborns. The findings provide baseline data for interpreting biotinidase activity and highlight the importance of standardized sample collection, transport, and testing.

Background: In Mongolia, cervical cancer accounted for 11.9% of all cancers diagnosed in women and 7.3% of cancer-related deaths in 2017, ranking as the third most common cancer among women. The American Society for Radiation Oncology (ASTRO) guidelines recommend concurrent chemo-radiotherapy (CCRT) as a standard and effective treatment for patients with FIGO stage IB3–IVA cervical cancer. Accurate assessment of tumor response following CCRT is essential for evaluating treatment efficacy, identifying residual disease, and estimating the risk of recurrence. Magnetic resonance imaging (MRI) is widely used to assess tumor size, local extent, parametric involvement, and post-treatment morphological changes. In contrast, 18F-FDG PET/CT provides both anatomical and functional information and enables quantitative assessment of tumor metabolic activity using the standardized uptake value (SUV). Aim: To estimate the relationship between treatment response to concurrent chemo-radiotherapy and radiological parameters obtained from MRI and 18F-FDG PET/CT in patients with cervical cancer. Materials and Methods: This retrospective study included 35 patients with histo-pathologically confirmed cervical carcinoma who received concurrent chemo-radiotherapy at the Department of Radiation Oncology, National Cancer Center, between 2024 and 2025. Pelvic MRI examinations were performed using a 1.5-T Siemens MRI system to evaluate tumor dimensions and local tumor characteristics before and after treatment. 18F-FDG PET/CT was performed to assess the metabolic activity of the primary tumor, and the maximum SUV was measured. Tumor response following CCRT was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. The relationships between tumor response, changes in tumor size, and pre-treatment SUV were statistically analyzed. Result: A total of 35 patients aged 32–73 years were included in the study, with a mean age of 51.2±12.6 years. The mean baseline longitudinal tumor diameter measured by MRI was 54.3±15.8 mm. Twenty-eight patients (80.0%) had tumors larger than 4 cm, whereas 7 (20.0%) had tumors smaller than 4 cm. According to the FIGO staging system, 22 patients (62.9%) had stage IIIC1 disease, 7 (20.0%) had stage IIIC2, 3 (8.6%) had stage IIIB, 2 (5.7%) had stage IIB, and 1 (2.9%) had stage IVA disease. Histopathologically, 31 patients (88.6%) had squamous cell carcinoma, 3 (8.6%) had adenocarcinoma, and 1 (2.9%) had clear cell carcinoma. Of the 35 patients, 23 (65.7%) had reached the scheduled post-treatment follow-up time and were evaluable for treatment response according to RECIST 1.1, whereas 12 patients (34.3%) had not yet reached the scheduled time for post-treatment assessment. Among the 23 evaluable patients, 15 (65.2%) achieved a complete response (CR), while 8 (34.8%) achieved a partial response (PR). Following CCRT, the longest tumor diameter measured by MRI decreased by a mean of 94.8% in the CR group and 65.3% in the PR group. The reduction in tumor diameter was significantly greater in the CR group than in the PR group (p=0.0016). The mean baseline primary tumor SUVmax on 18F-FDG PET/CT was 16.0±9.8 in the CR group and 24.3±14.5 in the PR group. Although the baseline SUVmax tended to be lower in the CR group, the difference did not reach statistical significance (Mann–Whitney U test, p=0.059). A higher baseline SUVmax tended to be associated with a smaller reduction in tumor diameter following CCRT. Conclusion CCRT resulted in a significant reduction in primary tumor size in patients with cervical cancer. The reduction in tumor size was significantly greater among patients who achieved a complete response than among those who achieved a partial response. Although pre-treatment 18F-FDG PET/CT findings suggest that MRI-based tumor size assessment combined with metabolic information from 18F-FDG PET/CT may provide complementary information for evaluating treatment response following CCRT.

Background: Pulmonary alveolar proteinosis (PAP) is a rare lung disorder characterized by the accumulation of surfactant within the alveoli, leading to impaired gas exchange and respiratory insufficiency. Although the disease is uncommon, it significantly affects patients’ quality of life and requires specific diagnostic and therapeutic approaches. Whole lung lavage (WLL) is considered the standard treatment; however, it has not been widely implemented in Mongolia. We report the first successful case of WLL performed for PAP in Mongolia. Case Presentation: A 56-year-old male presented with dyspnea. Chest computed tomography demonstrated a bilateral “crazy paving” pattern. Bronchoalveolar lavage fluid was positive for periodic acid–Schiff (PAS) staining, and anti–GM-CSF antibodies were detected, confirming the diagnosis of PAP. WLL was performed under general anesthesia using a double-lumen endotracheal tube with bronchoscopic guidance. One lung was ventilated with 100% oxygen while the contralateral lung was sequentially lavaged with 800–1000 mL of warm (37°C) saline per cycle until the effluent became clear. A total of approximately 20 liters of saline was used. Result: The procedure was completed successfully without complications. Following treatment, the patient showed marked clinical improvement with reduced dyspnea and increased exercise tolerance. Oxygen saturation improved from 88% to 93%, and spirometric parameters (FVC, FEV₁) demonstrated improvement. Chest imaging revealed a reduction in pulmonary opacities. Conclusion This case demonstrates the successful implementation of whole lung lavage (WLL) in Mongolia and highlights its importance in improving the diagnostic and therapeutic capacity for rare pulmonary diseases such as pulmonary alveolar proteinosis. The procedure resulted in significant improvement in clinical, functional, and radiological parameters, consistent with findings from international studies. Early diagnosis of PAP and the adoption of standardized protocols in accordance with international guidelines are essential to optimize treatment outcomes and enhance patients’ quality of life.

Background: Congenital hypothyroidism (CH) is a condition characterized by a decrease in the amount of thyroid hormones in the blood or a complete lack of thyroid function due to a decrease in the amount of thyroid hormones in the blood or a complete lack of thyroid hormones. CH occurs in 1 per 3000-4000 live births worldwide. The clinical symptoms of CH are initially subtle, usually appearing within a month of birth, and if diagnosis and treatment are delayed, it can lead to physical and mental developmental delays and eventual disability. The cause of the disease is not fully known, but it is believed to be influenced by maternal iodine deficiency and mutations in genes responsible for neonatal thyroid development (TSHR, PAX8, NKX2-1, and FOXE1 transcription factors). More than 40 types of TSHR gene mutations are causing CH. Studies conducted in Japan, China, and Taiwan have shown that the p.R450H mutation in the TSHR gene is a risk factor for CH. In Mongolia, a newborn screening analysis of congenital hypothyroidism revealed a rate of 1 case per 2091 live births in 2021, which is higher than the global average. However, there is a lack of molecular genetic research on this condition in the country. Aim: To identify of p.R450H mutation in the TSHR gene among neonates diagnosed with congenital hypothyroidism through neonatal screening Materials and Methods: The study used dried blood spots from 17 children diagnosed with congenital hypothyroidism at Mongolian-Japanese University hospital and Central Hospital of MNUMS from 2012 to 2024. To identify an optimal method for DNA extraction from dried blood samples, we evaluated five different protocols. DNA was extracted using the method that yielded the highest quantity and purity, and the TSHR gene was subsequently amplified by PCR. Detecting the p.R450H mutation of the TSHR gene, the PCR product was cut with Faul restriction enzyme and the results were evaluated by gel electrophoresis. Results: In our study, DNA isolation from dried blood using methods 1 and 2 had high yield and purity, so we isolated DNA from samples of 17 children diagnosed with congenital primary hypothyroidism and amplified the TSHR gene by PCR. When the PCR products were run through gel electrophoresis, 14 samples were amplified by PCR. After that, the genotype of the p.R450H mutation of the TSHR gene was determined by fragment length polymorphism analysis, and 11 (78.6%) samples were found to have the G/G genotype, 2 (14.3%) samples were found to have the G/A genotype, and 1 (7.1%) sample was found to have the A/A genotype, respectively. Conclusion Among children with congenital hypothyroidism diagnosed through newborn screening test between 2012 and 2024, the p.R450H homozygous and heterozygous mutation in the TSHR gene was 21.4%.

Background: Diffuse large B-cell lymphoma (DLBCL) is a common subtype of non-Hodgkin lymphoma of B-lymphocyte origin, characterized by an aggressive clinical course. Clinically, it most often presents with lymphadenopathy and “B symptoms,” including fever, night sweats, and weight loss. However, in some cases, the disease predominantly involves extranodal organs, such as the spleen, and may present with nonspecific manifestations, thereby posing a diagnostic challenge. Case presentation: A 36-year-old male patient presented with high-grade fever of unknown origin, dyspnea, generalized weakness, sweating, and a 7–8 kg weight loss over one month. Clinical evaluation and laboratory investigations revealed massive splenomegaly measuring 15 × 20 × 20 cm, progressive thrombocytopenia, anemia, and elevated C-reactive protein and lactate dehydrogenase levels. Diagnostic workup for infection, tuberculosis, viral infection, and autoimmune disease did not reveal findings sufficient to establish an alternative diagnosis. Because focal splenic lesions and suspected splenic infarction were identified, splenectomy was performed. Histopathological and immunohistochemical examination of the splenic tissue demonstrated CD20+, CD79a+, BCL2+, CD3−, CD8−, CD30−, and ALK− expression, confirming the final diagnosis of diffuse large B-cell lymphoma. Although DLBCL itself is a common form of non-Hodgkin lymphoma, this case is clinically rare and diagnostically challenging because it presented with predominant splenic involvement, massive splenomegaly measuring 15×20×20 cm, treatment-resistant fever, progressive thrombocytopenia, and imaging findings mimicking splenic infarction. Conclusion In patients presenting with fever of unknown origin that is resistant to treatment, massive splenomegaly, thrombocytopenia, elevated LDH, and increased inflammatory markers, lymphoproliferative disorders should be considered early in the differential diagnosis in addition to infectious causes. Histopathological and immunohistochemical examination play a crucial role in confirming the diagnosis.

Background: This study aimed to estimate the association between mRNA coronavirus disease 2019 (COVID-19) vaccine exposure during pregnancy and the risks of preterm birth and congenital malformations leveraging a national population data. Methods: This retrospective cohort study utilized national data from the National Health Insurance System, linking maternal and infant records with COVID-19 vaccination registries.Newborns with congenital malformations were identified using diagnosis codes. The analysis included women aged 20–49 who gave live births between February 2022 and December 2022. Odds ratios (ORs) for preterm birth and any congenital malformation per COVID-19 vaccination during pregnancy compared to 1:4 matched unvaccinated controls, adjusted for maternal age, residential area, employment, income, disability, month of conception, prepregnancy obesity, smoking, and severe acute respiratory syndrome coronavirus 2 infection prior to pregnancy, were calculated. We compared the risk of two outcomes between BNT162b2 and mRNA-1273. Results: Among 106,692 women who gave birth during the study period, 8,966 (8.4%) received a COVID-19 vaccination during pregnancy. Of the newborns, 7,039 (6.6%) were preterm births and 7,658 (7.2%) had congenital malformations. COVID-19 vaccination during pregnancy was associated with a comparable risk of preterm birth (OR, 1.03; 95% confidence interval [CI], 0.77–1.36) and a similar risk of congenital malformations (0.90; 95% CI, 0.72–1.12) compared to non-vaccinees. The ORs of preterm birth (1.02; 95% CI, 0.77–1.36) and congenital malformation (0.91; 95% CI, 0.73–1.14) for mRNA-1273 were comparable to those for BNT162b2. Conclusion COVID-19 vaccines during pregnancy poses no increased risk of preterm birth and congenital malformations compared to those not exposed to the vaccine, with similar risk levels observed between the two mRNA vaccines. This finding provides additional evidence supporting the safety of COVID-19 vaccines.

Background: The COVID-19 pandemic has placed an extraordinary strain on healthcare systems worldwide, underscoring the need for evidence-based pharmacotherapy and rational use of medicines. Despite the availability of international and national treatment guidelines, notable variations in drug selection and utilization persist across healthcare institutions. Evaluating medication use according to clinical severity is vital for ensuring therapeutic rationality, improving patient outcomes, and optimizing pharmaceutical resource management. Aim: The aim of this study was to assess medication use and associated costs among inpatients diagnosed with COVID-19 at the Mongolia–Japan Hospital of MNUMS and the National Center for Communicable Diseases through ABC analysis Materials and Methods: : A retrospective, document-based study was conducted at the Mongolia-Japan Hospital (MJH) and the National Center for Communicable Diseases (NCCD) in Ulaanbaatar. Medical and pharmacy records of 1,012 inpatients diagnosed with COVID-19 between April 18 and December 31, 2021, were reviewed. Drug utilization was assessed using the ABC analysis method, classifying medicines based on their proportional contribution to total pharmaceutical expenditure. Comparative analyses were performed to identify differences in utilization patterns between hospitals and across clinical severity levels. Results: Of the total pharmaceutical expenditure for COVID-19 treatment, six medicines (4.5% of all drugs) were categorized as Class A, accounting for 69.7% of total costs. Class B included seven medicines (7.0%, 19.5% of total costs), while Class C comprised twenty-six medicines (88.6%, 10.6% of total costs). Remdesivir 100 mg injection, a Class A drug, represented 18.5% of total drug expenditure at MJH (used in 78 patients) and 36.2% at NCCD (used in 133 patients). Overall, approximately 70% of total expenditure was concentrated in a small number of high-cost medicines, indicating potential inefficiencies in pharmaceutical resource utilization. Conclusion This study demonstrates that a limited number of high-cost medicines, particularly Remdesivir, accounted for the majority of COVID-19 treatment expenditures. Strengthening evidence-based prescribing, rational selection, and monitoring of high-cost drugs is essential to enhance resource efficiency, ensure equitable access, and sustain hospital pharmaceutical care systems during pandemic response and beyond.

Background: This study aimed to estimate the association between mRNA coronavirus disease 2019 (COVID-19) vaccine exposure during pregnancy and the risks of preterm birth and congenital malformations leveraging a national population data. Methods: This retrospective cohort study utilized national data from the National Health Insurance System, linking maternal and infant records with COVID-19 vaccination registries.Newborns with congenital malformations were identified using diagnosis codes. The analysis included women aged 20–49 who gave live births between February 2022 and December 2022. Odds ratios (ORs) for preterm birth and any congenital malformation per COVID-19 vaccination during pregnancy compared to 1:4 matched unvaccinated controls, adjusted for maternal age, residential area, employment, income, disability, month of conception, prepregnancy obesity, smoking, and severe acute respiratory syndrome coronavirus 2 infection prior to pregnancy, were calculated. We compared the risk of two outcomes between BNT162b2 and mRNA-1273. Results: Among 106,692 women who gave birth during the study period, 8,966 (8.4%) received a COVID-19 vaccination during pregnancy. Of the newborns, 7,039 (6.6%) were preterm births and 7,658 (7.2%) had congenital malformations. COVID-19 vaccination during pregnancy was associated with a comparable risk of preterm birth (OR, 1.03; 95% confidence interval [CI], 0.77–1.36) and a similar risk of congenital malformations (0.90; 95% CI, 0.72–1.12) compared to non-vaccinees. The ORs of preterm birth (1.02; 95% CI, 0.77–1.36) and congenital malformation (0.91; 95% CI, 0.73–1.14) for mRNA-1273 were comparable to those for BNT162b2. Conclusion COVID-19 vaccines during pregnancy poses no increased risk of preterm birth and congenital malformations compared to those not exposed to the vaccine, with similar risk levels observed between the two mRNA vaccines. This finding provides additional evidence supporting the safety of COVID-19 vaccines.

Background: This study aimed to estimate the association between mRNA coronavirus disease 2019 (COVID-19) vaccine exposure during pregnancy and the risks of preterm birth and congenital malformations leveraging a national population data. Methods: This retrospective cohort study utilized national data from the National Health Insurance System, linking maternal and infant records with COVID-19 vaccination registries.Newborns with congenital malformations were identified using diagnosis codes. The analysis included women aged 20–49 who gave live births between February 2022 and December 2022. Odds ratios (ORs) for preterm birth and any congenital malformation per COVID-19 vaccination during pregnancy compared to 1:4 matched unvaccinated controls, adjusted for maternal age, residential area, employment, income, disability, month of conception, prepregnancy obesity, smoking, and severe acute respiratory syndrome coronavirus 2 infection prior to pregnancy, were calculated. We compared the risk of two outcomes between BNT162b2 and mRNA-1273. Results: Among 106,692 women who gave birth during the study period, 8,966 (8.4%) received a COVID-19 vaccination during pregnancy. Of the newborns, 7,039 (6.6%) were preterm births and 7,658 (7.2%) had congenital malformations. COVID-19 vaccination during pregnancy was associated with a comparable risk of preterm birth (OR, 1.03; 95% confidence interval [CI], 0.77–1.36) and a similar risk of congenital malformations (0.90; 95% CI, 0.72–1.12) compared to non-vaccinees. The ORs of preterm birth (1.02; 95% CI, 0.77–1.36) and congenital malformation (0.91; 95% CI, 0.73–1.14) for mRNA-1273 were comparable to those for BNT162b2. Conclusion COVID-19 vaccines during pregnancy poses no increased risk of preterm birth and congenital malformations compared to those not exposed to the vaccine, with similar risk levels observed between the two mRNA vaccines. This finding provides additional evidence supporting the safety of COVID-19 vaccines.

Background : Diabetic ketoacidosis, an early and common complication at the initial diagnosis of Type 1 Diabetes Mel litus (T1DM), remains a significant clinical concern. The high prevalence of this complication in the pediatric population provided the rationale for conducting the present study. Aim: Our study aims to compare the incidence, clinical features, and physical measurements associated with diabetic ketoacidosis (DKA) at the time of initial diagnosis of Type 1 Diabetes Mellitus (T1DM), and to classify the severity of DKA based on selected laboratory findings. Materials and Methods: We conducted a retrospective observational study of newly diagnosed T1DM with DKA in children aged less than 18 years old at National Center for Maternal and Child Health during the period 2017-2022. The study compared the analysis of medical and laboratory records from patients medical charts. The severity of diabetic ketoacidosis (DKA) was classified based on laboratory criteria according to the 2022 guidelines of the International Society for Pediatric and Adolescent Diabetes (ISPAD). The study data were analyzed using STATA-16.0. Results: During the period from 2017 to 2022, a total of 124 children under 18 years of age (mean age: 9.11±3.84 years) were newly diagnosed with T1DM and included in the study, of whom 67.7% (n=84) presented with diabetic ketoacidosis (DKA). Of the children with DKA, 57.2% (n=48) had severe, 17.8% (n=15) had moderate, and 25.0% (n=21) had mild severity. Girls were more frequently affected (67.1%, n=47; p=0.871). Having a viral infection before the first diagnosis of type 1 diabetes (51.2%, n=43, p=0.011) and having high blood glucose levels at that time (25.8±9.32 mmol/l, p=0.012) were statistically significantly associated with diabetic ketoacidosis. The blood gas analysis of children with ketoacidosis showed pH 7.05±0.15, HCO3 8.68±4.27 mEq/l, and the group with severe ketoacidosis had higher blood potassium levels (4.08±0.8 mEq/l, 3.6±0.56 mEq/l, p=0.049) and blood glucose levels (28.37±9.23 mmol/L, 21.96±9.18 mmol/L, p=0.012) compared to the group with mild ketoacidosis. Conclusions 1. Diabetic ketoacidosis (DKA) was identified in 67.7% (n=84) of the children included in the study. 2. At the initial diagnosis of Type 1 Diabetes Mellitus (T1DM), vomiting and fatigue were the predominant clinical manifestations of DKA. 3. Severe DKA was observed in 57.1% (n=48) of the participants, with elevated serum potassium and glucose levels noted as contributing factors to the severity of ketoacidosis.