Background: Rosai–Dorfman disease (RDD) is a rare, benign disorder of non-Langerhans cell histiocytic origin with an unknown etiology, which can affect the skin and other organ systems. The incidence in the United States is approximately 1:200,000. In Mongolia, four cases have been registered over the past five years under the ICD-10 code D76.0. Case presentation: A 59-year-old female patient initially presented to the Dermatology Department of the National Center for Dermatology with clustered, elevated lesions on the medial aspect of the right thigh, including papules, plaques, and nodules of round to oval shape. Additionally, multiple erythematous macules and papules were observed on both lower legs. For diagnostic purposes, a histopathological examination was performed, revealing histiocytes with abundant cytoplasm and lymphocytes within the cytoplasm (emperipolesis). The diagnosis was confirmed based on dermoscopic and immunohistochemical findings. Management: The patient was referred to the Mongolian-Japanese Hospital of MNUMS, where the remaining nodular lesions were surgically excised in the surgical department. Further follow-up was referred to a hematologist. Computed tomography (CT) imaging was recommended. Cutaneous-limited RDD may resolve spontaneously in some cases; however, when multiple organ systems are involved or when associated forms are present, referral to hematology and oncology specialists for systemic therapy is required. Conclusion It is important to differentiate this disease from other dermatological conditions presented with macules, papules, and nodules through clinical evaluation, histopathology, immunohistochemistry, and dermoscopic examination.

Background: Natural protection against Mycobacterium tuberculosis is based on cell-mediated immunity, which most importantly involves CD4+ and CD8+ T-cell subsets. Therefore, the evaluation of CD4+ and CD8+ T-cell profi les are important to evaluate cell-mediated immunity. Immuno-regulating therapy is important in increase of T cell subsets. Objective: To determine some T-cell subsets in active pulmonary tuberculosis patients following immunoregulating treatment in intensive phase of antituberculosis treatment, so to evaluate the treatment effect. Method: This study was conducted in TB clinic of National Center for Communicable Diseases (NCCD) between Aug 2008 and Mar 2009. CD4+ and CD8+-T cells were evaluated in 50 active pulmonary tuberculosis (infi ltrative form) cases before antituberculosis treatment (25 cases with Salimon-Study group, 25 cases without SalimonControl group) Patients with chronic disease, pregnant and alcohol users are excluded. The T cell subsets count was performed by FACSCount fl ow cytometer at the Immunology Laboratory of the NCCD,Mongolia.The monoclonal antibodies to CD3, CD4 and CD8 (Becton Dickinson) were used for the analysis. Result: CD4 count was 605,1242,7 cells/microL, CD8 count-470,92235,7 cells/microL, CD3 count-1130,7425,6 cells/microL, CD4/CD8 ratio was-1,480,67. CD4, CD8, CD3 cells were signifi cantly lower (P=0.05) in active pulmonary TB patients than in healthy Mongolian. And these subsets were signifi cantly lower in older patients (>50 age).There was no statistical signifi cance in sex and other age groups (p>0, 05). There were statistical signifi cances such as CD4 count, CD4/CD8 ratio (CD4-733,95314,38 cells/micro, CD4/CD8 ratio-1.870,7 in treatment group, CD4-570,54213.07 cells/micro, CD4/CD8 ratio-1.260.45 in control group) between TB and control group at the end of intensive phase of antituberculosis treatment (=0,05, =0,001). However, there were not any signifi cance CD8 count and CD3 count between two groups (CD8-423,68174,28 cells/microL, CD3-1212,27453,98 cells/microL in treatment group, CD8-500,67203,74cells/microL, CD3 -1139,33 386,47 cells/ microL in control group) (=0,05). Conclusion: 1. T cell subsets were signifi cantly lower in active,new,smear positive, pulmonary TB patients than in healthy Mongolians (p=0.05). 2. The statistical signifi cance is observed in 50 years and older TB patients (p=0.05). 3. CD4, CD4/CD8 were signifi cantly higher in patients treated with immuno-regulating treatment than in patients of control group (=0,05, =0,001).