Background: Staphylococcus aureus (S. aureus) is a leading cause of skin and soft tissue infections. The prevalence of methicillin-resistant (MRSA) and multidrug-resistant (MDR) strains has been increasing globally in recent years. In Mongolia, data on MRSA prevalence and antimicrobial susceptibility in purulent skin infections remain limited. Aim: To assess the prevalence of MRSA and MDR S. aureus and their antimicrobial susceptibility patterns in purulent skin infections. Materials and Methods: This laboratory-based retrospective study analyzed 22,753 samples collected between 2015−2025 at the National Dermatology Center of Mongolia, in which S. aureus was identified. MDR was defined according to the Magiorakos criteria as resistance to three or more antibiotic classes. Prevalence was expressed with 95% confidence intervals (CI). Group differences were assessed using the chi-square (χ²) test; and age- and sex-related risks were estimated using odds ratios (OR) with 95% CI. A p-value <0.05 was considered statistically significant. Results: MRSA was detected in 18.8% (n=4,278) and MDR in 40.7% (n=9,258) of cases. The prevalence of MRSA increased significantly from 0–1.6% during 2015–2019 to 15–34.2% during 2020–2025 (p<0.001). MDR prevalence peaked at 53.9% (n=1,682) in 2022. No statistically significant sex differences were observed for MRSA (female: 2,331; male: 1,947) or MDR (female: 4,958; male: 4,300) (p>0.05). MRSA prevalence was highest in children under 1 year (47.4%) and lowest in those aged 15–24 years (14.8%), while MDR prevalence increased significantly with age and was highest among individuals aged ≥81 years (p<0.001). The presence of MRSA was associated with a 16.76-fold higher likelihood of MDR S. aureus (p<0.001). Antibiotic resistance was highest for penicillin-class antibiotics (ampicillin 91.5%, amoxicillin 75.4%), whereas susceptibility remained high for vancomycin (4.4% resistance), nitrofurantoin (4.6%), and amikacin (10.1%). Conclusion Over the past decade, the prevalence of MRSA and MDR S. aureus in purulent skin infections has increased markedly. Although resistance to penicillin-class antibiotics remains high, susceptibility to vancomycin and nitrofurantoin is largely preserved. The higher prevalence observed in younger and older age groups highlights the need to strengthen infection control measures and promote the rational use of antibiotics.

Background: Histopathological examination of skin tissue plays an important role in the diagnosis of dermatological diseases; however, data on surgically excised skin specimens remain limited in Mongolia. Aim: To classify benign and malignant tumors based on histopathological findings of surgically excised skin tissue specimens, determine surgical margin status, and evaluate the age and sex distribution of these conditions. Materials and Methods: This retrospective observational study was conducted using data on surgically excised tissue specimens collected in the outpatient department of the National Dermatology Center between January 2023 and March 2026. A total of 361 patients were identified. Four cases with indeterminate histopathological diagnoses were excluded, leaving 357 patients for final analysis. Data on age, sex, diagnosis, and surgical margin status were collected and analyzed on Microsoft Excel programm. Histopathological diagnoses were classified as benign or malignant tumors. Associations between categorical variables were assessed using the chi-square test, with statistical significance set at p < 0.05. Results: Among 357 patients, 135 (37.8%) were male and 222 (62.2%) were female, with a mean age of 41.8 years. The 20–39-year age group accounted for the largest proportion of cases (39.5%). Histopathological examination showed that 326 cases (91.32%) were benign and 31 cases (8.68%) were malignant. Among benign tumors, melanocytic nevus was the most common diagnosis, while basal cell carcinoma was the most common malignant tumor. The frequency of malignant tumors increased significantly with age (p < 0.001). Patients aged ≥60 years had significantly higher odds of malignancy compared with younger patients (OR = 8.19, 95% CI: 3.79–17.69). Malignant lesions were significantly more likely to have positive (involved) surgical margins than benign lesions. Conclusion Most surgically excised skin tissue specimens were benign; however, the likelihood of malignancy increased significantly with age. Surgical margin assessment is clinically important for improving prognosis, reducing the risk of recurrence, and guiding treatment management.

Description: Due to the increased prevalence of penicillin-resistant bacteria in the treatment of staphylococcal infection in 1961 were introduced into clinical practice one of the semi-synthetic drugs resistant to penicillinase which calls methicillin. However immediately after this event has been reported it’s tolerance [1,2,3].
Methicillin-resistant staphylococcus (MRSA/MTSA) has been widely reported in the world and since the 1980s is now considered a highly contagious infection. MTSA infection and mortality rates are twice as high as methicillin-sensitive staphylococcal aureus infections and it caused to increase hospital bed costs [4,5]. Materials and methodology: The study included a sample of all samples submitted to the NCD for bacteriological analysis in 2018, 2019 and 2020.
Bacteriological specimens were obtained from swabs, wounds, urine, and throat swabs to identify and physically identify methicillin-resistant staphylococcus aureus. The research objectives were obtained from the NCD journal including all investigations from January 1 2018 to December 31, 2020 using the Descriptive Research Method. Results: In 2018, a total of 6419 bacteriological tests were performed with the growth of 4693 bacteria, in 2019 out of 7281 bacteriological tests were performed with the growth of 5485 bacteria, and in 2020 out of 8275 bacteriological tests were performed with the growth of 6894 bacteria.
The MTSA positeve tests accounted 269 (4.1%) bacteriological tests in 2018, in 2019 412 (5.6%) and in 2020 were, 781 (9.4%) from total bacteriological tests fot these years. Conclution The need for bacteriological testing is increasing year by year, which indicates an increase in bacterial infections. Also increased cases of MTSA are reported in the NCD during 2018-2020. The MTSA infections are more common in swabs and pustules.