Mycobacterium tuberculosis clinical isolates of the Beijing and East-African Indian lineage induce fundamentally different host responses in mice compared to H37Rv

Substantial differences exist in virulence among Mycobacterium tuberculosis strains in preclinical TB models. In this study we show how virulence affects host responses in mice during the first four weeks of infection with a mycobacterial strain belonging to the Beijing, East-African-Indian or Euro-American lineage. BALB/c mice were infected with clinical isolates of the Beijing-1585 strain or the East-African Indian (EAI)-1627 strain and host responses were compared to mice infected with the non-clinical H37Rv strain of the Euro-American lineage. We found that H37Rv induced a 'classical' T-cell influx with high IFN-γ levels, while Beijing-1585 and EAI-1627 induced an influx of B-cells into the lungs together with elevated pulmonary IL-4 protein levels. Myeloid cells in the lungs appeared functionally impaired upon infection with Beijing-1585 and EAI-1627 with reduced iNOS and IL-12 expression levels compared to H37Rv infection. This impairment might be related to significantly reduced expression in the bone marrow of IFN-γ, TNF-α and IFN-β in mice infected with Beijing-1585 and EAI-1627, which could be detected from the third day post infection onwards. Our findings suggest that increased virulence of two clinical isolates compared to H37Rv is associated with a fundamentally different systemic immune response, which already can be detected early during infection

Eye Lesions in Patients After One Year of Kidney Transplantation

Nguyen Le Trung,1,2 Pham Quoc Toan,3 Nguyen Kien Trung,4 Vu Anh Tuan,1 Nguyen Thu Huyen5 1Vietnam Department of Ophthalmology, Hanoi Medical University, Hanoi, Vietnam; 2Vietnam Department of Ophthalmology, Military Hospital 103, Hanoi, Vietnam; 3Vietnam Department of Nephrology, Military Hospital 103, Hanoi, Vietnam; 4Vietnam Department of Trauma, National Eye Hospital, Hanoi, Vietnam; 5Vietnam Department of Ophthalmology, National Military Hospital 108, Hanoi, VietnamCorrespondence: Pham Quoc Toan, Email [email protected]: Determine the incidence of some eye lesions in kidney transplant patients after one year at Military Hospital 103 and comment on related factors.Patients and Methods: A cross-sectional study description of 111 kidney transplant patients (222 eyes) at Military Hospital 103. We assessed several eye lesions, including dry eyes, corneal conjunctival calcification, cataracts, and retinopathy.Results: The rate of retinopathy was 84.7%, dry eye was 59.5%, cataract was 29.7%, and corneal conjunctival calcification was 24.8%, atrophy optic nerve was 9.9%, epiretinal membrane was 1.8%. Post-transplant influence factors associated with cataracts include the dose of prednisolone (OR= 1.6, p < 0.05) and post-transplant diabetes (OR=1.4, p < 0.05). The influence factor related to the atrophy of the optic nerve is systemic infection after transplantation (OR=2.4, p < 0.05).Conclusion: Retinopathy accounted for the highest rate, followed by dry eye disease; cataracts ranked third; and finally, calcified corneal conjunctiva. Factors that affect cataracts are diabetes mellitus and prednisolone dose. Factors affecting optic nerve atrophy are infections after kidney transplantation.Keywords: kidney transplant, corneal conjunctival calcification, dry eyes, hypertensive retinopath

Diagnostic Performance of Magnetic Resonance Imaging in Discriminating Benign and Malignant Soft Tissue Tumors

Nguyen Duy Hung,1,2,&ast; Nguyen-Thi Tam,2 Dang Khanh Huyen,2 Nguyen-Van Thi,3 Nguyen Minh Duc4,&ast; 1Department of Radiology, Viet Duc Hospital, Hanoi, Vietnam; 2Department of Radiology, Hanoi Medical University, Hanoi, Vietnam; 3Department of Radiology, Vietnam National Cancer Hospital, Hanoi, Vietnam; 4Department of Radiology, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam&ast;These authors contributed equally to this workCorrespondence: Nguyen Minh Duc, Department of Radiology, Pham Ngoc Thach University of Medicine, 2 Duong Quang Trung Ward 12 District 10, Ho Chi Minh City, 700000, Vietnam, Email [email protected]: The study aimed to evaluate the role of magnetic resonance imaging (MRI) in differentiating between primary benign and malignant soft tissue tumors (STTs).Patients and Methods: The study was carried out on 110 patients with histopathological diagnoses of STTs. All patients underwent routine MRI before surgery/biopsy at Viet Duc University Hospital or Vietnam National Cancer Hospital, Hanoi, Vietnam, from January 2020 to October 2022. Data on preoperative MRI as well as the clinical features and pathological results of the patients were collected retrospectively. Univariate and multivariate linear regression were used to analyze the relationship between imaging, clinical parameters, and the ability to differentiate malignant from benign STTs.Results: Among 110 patients (59 men and 51 women), 66 had benign tumors and 44 had malignant tumors. The qualitative values that were significant in distinguishing between benign and malignant STTs were hypointensity on T1-weighted images (T1W; p< 0.001), hypointensity on T2-weighted images (T2W; p=0.003), cysts (p=0.003)), necrosis (p< 0.001), fibrosis (p=0.023), hemorrhage (p< 0.001), lobulated margin (p< 0.001), ill-defined border (p< 0.001), peritumoral edema (p< 0.001), vascular involvement (p< 0.001), and heterogeneous enhancement (p< 0.001). Regarding quantitative values, age (p=0.009), size (p< 0.001), T1W signal quantification value (p=0.002), and T2W signal quantification value (p=0.007) showed statistically significant differences between benign and malignant tumors. Multivariate linear regression analysis showed that the combination of peritumoral edema and heterogeneous enhancement was the most valuable in the differential diagnosis of malignant tumors from benign tumors.Conclusion: MRI is valuable in discriminating between malignant and benign STTs. The presence of cysts, necrosis, hemorrhage, lobulated margin, ill-defined border, peritumoral edema, heterogeneous enhancement, vascular involvement, and T2W hypointensity is suggestive of malignant lesions, especially signs of peritumoral edema and heterogeneous enhancement. Advanced age and large tumor size are also suggestive of soft tissue sarcomas.Keywords: soft tissue tumors, soft tissue sarcoma, magnetic resonance imaging, tissue characterization, size, predictio

Clustering of Beijing genotype Mycobacterium tuberculosis isolates from the Mekong delta in Vietnam on the basis of variable number of tandem repeat versus restriction fragment length polymorphism typing.

Contains fulltext : 125549.pdf (publisher's version ) (Open Access)BACKGROUND: In comparison to restriction fragment length polymorphism (RFLP) typing, variable number of tandem repeat (VNTR) typing is easier to perform, faster and yields results in a simple, numerical format. Therefore, this technique has gained recognition as the new international gold standard in typing of Mycobacterium tuberculosis. However, some reports indicated that VNTR typing may be less suitable for Beijing genotype isolates. We therefore compared the performance of internationally standardized RFLP and 24 loci VNTR typing to discriminate among 100 Beijing genotype isolates from the Southern Vietnam. METHODS: Hundred Beijing genotype strains defined by spoligotyping were randomly selected and typed by RFLP and VNTR typing. The discriminatory power of VNTR and RFLP typing was compared using the Bionumerics software. RESULTS: Among 95 Beijing strains available for analysis, 14 clusters were identified comprising 34 strains and 61 unique profiles in 24 loci VNTR typing ((Hunter Gaston Discrimination Index (HGDI = 0.994)). 13 clusters containing 31 strains and 64 unique patterns in RFLP typing (HGDI = 0.994) were found. Nine RFLP clusters were subdivided by VNTR typing and 12 VNTR clusters were split by RFLP. Five isolates (5%) revealing double alleles or no signal in two or more loci in VNTR typing could not be analyzed. CONCLUSIONS: Overall, 24 loci VNTR typing and RFLP typing had similar high-level of discrimination among 95 Beijing strains from Southern Vietnam. However, loci VNTR 154, VNTR 2461 and VNTR 3171 had hardly added any value to the level of discrimination

Validation of the GenoType MTBDRplus assay for diagnosis of multidrug resistant tuberculosis in South Vietnam.

Contains fulltext : 124360.pdf (publisher's version ) (Open Access)BACKGROUND: To control multidrug resistant tuberculosis (MDR-TB), the drug susceptibility profile is needed to guide therapy. Classical drug susceptibility testing (DST) may take up to 2 to 4 months. The GenoType MTBDRplus test is a commercially available line-probe assay that rapidly detects Mycobacterium tuberculosis (MTB) complex, as well as the most common mutations associated with rifampin and isoniazid resistance.We assessed sensitivity and specificity of the assay by using a geographically representative set of MTB isolates from the South of Vietnam. METHODS: We re-cultured 111 MTB isolates that were MDR, rifampin-resistant or pan-susceptible according to conventional DST and tested these with the GenoType MTBDRplus test. RESULTS: By conventional DST, 55 strains were classified as MDR-TB, four strains were rifampicin mono-resistant and 52 strains were susceptible to all first-line drugs. The sensitivity of the GenoType MTBDRplus was 93.1% for rifampicin, 92.6% for isoniazid and 88.9% for the combination of both; its specificity was 100%. The positive predictive value of the GenoType MTBDRplus test for MDR-TB was 100% and the negative predictive value 90.3%. CONCLUSIONS: We found a high specificity and positive predictive value of the GenoType MTBDRplus test for MDR-TB which merits its use in the MDR-TB treatment program in Vietnam