Repositório Científico do Instituto Nacional de Saúde
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Reply to Wilson: The 4-Month Isoniazid, Rifapentine, Moxifloxacin, and Pyrazinamide Treatment Regimen for Drug-Susceptible Pulmonary Tuberculosis: A Word of Caution
Publication . Saukkonen, Jussi; Munsiff, Sonal; Winston, Carla; Duarte, Raquel; Mammen, Manoj
No abstract available
Painless but Visible: The Case Report of a Painless Facial Nodule in a Child
Publication . Vieitez-Frade, Joana; de Sousa, Diogo; Patrocínio, João; Gargaté, Maria João; Jesus, Miguel; Duarte, Cristina; Tapadinhas, Cristina
No abstract available
Mycobacterium appelbergii sp. nov., a Novel Species Isolated from a Drinking Water Fountain in a Rural Community
Publication . Roxo, Inês Cravo; Alarico, Susana; Fonseca, Ana; Machado, Daniela; Maranha, Ana; Tiago, Igor; Duarte, Raquel; Empadinhas, Nuno
Three isolates of a novel, rapidly growing, non-pigmented Mycobacterium species were recovered from the water and runoff of a public fountain in a rural village in central Portugal, formerly used by the local population as a source of drinking water and not accessible to animals. High-quality draft genome sequencing, in silico DNA–DNA hybridization, and phylogenetic analyses confirmed that isolates 21AC1T, 21AC14, and 21AC21 represent a previously undescribed species within the genus Mycobacterium, forming a distinct phylogenetic lineage closely related to Mycobacterium wolinskyi, Mycobacterium goodii and Mycobacterium smegmatis. MALDI-TOF MS analysis of the type strain 21AC1T revealed a unique spectral profile. A comprehensive polyphasic characterization was performed, including chemotaxonomic analyses of fatty acid and mycolic acid composition, as well as an extensive biochemical characterization. Their susceptibility to 12 antimicrobials was also assessed. The identification and characterization of novel nontuberculous mycobacteria species are of increasing environmental and clinical relevance, as infections by these opportunistic pathogens are on the rise globally. Based on our findings, we propose that isolates 21AC1T, 21AC14, and 21AC21 represent a novel species, for which we propose the name Mycobacterium appelbergii sp. nov., with the type strain designated as 21AC1T (=BCCM/ITM 501212 = DSM 113570) and the additional two strains as 21AC14 (=BCCM/ITM 501447 = DSM 118402) and 21AC21 (=BCCM/ITM 501448 = DSM 118403).
Diagnostic accuracy and predictive value of the QuantiFERON-TB gold plus assay for tuberculosis in immunocompromised individuals: a prospective TBnet study
Publication . Sester, Martina; Altet-Gomez, Neus; Andersen, Åse Bengaard; Arias-Guillén, Miguel; Avsar, Korkut; Bakken Kran, Anne-Marte; Bothamley, Graham; Nordholm Breschel, Anne Christine; Brown, James; Chesov, Dumitru; Ciobanu, Nelly; Cirillo, Daniela Maria; Crudu, Valeriu; de Souza Galvao, Malu; Dilektasli, Asli Görek; Dominguez, José; Duarte, Raquel; Dyrhol-Riise, Anne Ma; Goletti, Delia; Hoffmann, Harald; Ibraim, Elmira; Kalsdorf, Barbara; Krawczyk, Marcin; Kunst, Heinke; Lange, Berit; Lipman, Marc; Matteelli, Alberto; Milkiewicz, Piotr; Neyer, David; Nitschke, Martin; Oral, Haluk Barbaros; Palacios-Gutiérrez, Juan José; Petruccioli, Elisa; Raszeja-Wyszomirska, Joanna; Ravn, Pernille; Rupp, Jan; Spohn, Hanna-Elisa; Toader, Corina; Villar-Hernandez, Raquel; Wagner, Dirk; van Leth, Frank; Martinez, Leonardo; Pedersen, Ole Skouvig; Lange, Christoph
Background: In low tuberculosis (TB)-endemic countries, tuberculosis preventive therapy (TPT) is recommended for immunocompromised individuals with a positive immunodiagnostic test. This study aimed to assess the performance of the QuantiFERON-TB Gold Plus (QFT+) assay and predictive power for future tuberculosis in immunocompromised individuals.
Methods: In this prospective observational study, immunocompromised adults ≥18 years of age including people living with HIV (PLHIV), chronic renal failure, rheumatoid arthritis, solid-organ transplantation or stem-cell transplantation, and immunocompetent adults with and without TB-disease were recruited at 21 sites in 11 European countries and tested with the QFT+ assay. Individuals without TB-disease were followed up for the development of tuberculosis. TB incidence rates (IR) were calculated, stratified by QFT+ results and acceptance of TPT. This study is registered with Clinicaltrials.gov, NCT02639936.
Findings: A total of 2663 individuals (1115 female, 1548 male) were enrolled from 03/11/2015 to 29/03/2019. Persons without tuberculosis were followed up for at least two years. Among 1758 immunocompromised individuals without active tuberculosis, 13.6% had positive QFT+ results. Sensitivity and specificity for TB-disease were 70.0% (52.1-83.3%) and 91.4% (89.6-92.9%), respectively, in immunocompromised, and 81.4% (76.6-85.3%) and 96.0% (92.5-97.9%), respectively, in immunocompetent individuals. During 2457 cumulative years of follow-up among 932 individuals with chronic renal failure, rheumatoid arthritis, solid-organ transplantation or stem-cell transplantation, including 83 persons with a positive QFT+ test without TPT, no-one developed active tuberculosis. In contrast, among 642 PLHIV without TPT, one with an indeterminate QFT+ and 3/30 individuals with a positive QFT+ developed active tuberculosis; all had detectable HIV-replication and low CD4 T-cell counts (incidence 4.1 (95% CI (1.3-12.4) per 100 person-years). No individuals receiving TPT developed active tuberculosis during 269 years of follow-up.
Interpretation: In immunocompromised individuals in low TB-endemic countries, the 2-year-risk for active tuberculosis was highest among PLHIV with detectable HIV-replication and low CD4-counts. In this study, the QFT+ assay did not strongly predict progression to active tuberculosis, which emphasises the need to incorporate additional risk factors.
Re-classification of LDLR Variants through High-Throughput Functional Characterisation: Advancing Diagnosis in Familial Hypercholesterolaemia
Publication . Chora, Joana Rita; Islam, Mohammad Majharul; Alves, Ana Catarina; Pfisterer, Simon; Bourbon, Mafalda
Background: Familial hypercholesterolaemia (FH) is the most common autosomal disorder of lipid metabolism, affecting approximately 1 in 300 individuals. FH is characterised by markedly elevated plasma cholesterol levels from birth, predisposing to premature atherosclerotic cardiovascular disease. The identification of a pathogenic variant in a causative gene provides a definitive diagnosis and enables cascade screening of family members. However, a substantial proportion of FH variants remain classified as variants of uncertain significance (VUS), creating a critical gap in genetic diagnosis and patient management.
Purpose: This study aims to implement a high-throughput pipeline for the functional classification of LDLR variants, thereby enabling their clinical re-interpretation and integration into diagnostic practice.
Methods: Selected LDLR variants were divided into two groups: a validation set and a test set. The validation group included 7 variants previously classified as benign/likely benign and 50 variants previously classified as pathogenic/likely pathogenic. The test group comprised 131 VUS with no prior functional assessment. Functional activity was evaluated using an automated analysis platform based on multiplexed high-content imaging to quantify LDL uptake, as described previously (Islam, Tamlander, Hlushchenko, Ripatti, & Pfisterer, 2024). Variant classification followed FH VCEP LDLR-specific guidelines (Chora et al., 2022).
Results: In total, 187 LDLR variants were analysed. In the validation group, 44 variants demonstrated completely concordant results with previous classifications, 8 fell within an intermediate "grey zone" (70–90% LDL uptake), and only 5 pathogenic variants were misclassified, yielding a sensitivity of 88.4%, specificity and precision of 100%, and overall accuracy of 78.9%.
Among the test group, 51 variants exhibited <70% of wild-type LDL uptake, 41 showed >90% of wild-type uptake, and 39 fell into the intermediate range, requiring additional functional studies. Integrating these findings with other ACMG/AMP evidence codes, 47 variants were considered “hot VUS”, amenable to reclassification. Of these, 9 were reclassified as likely benign and 11 as likely pathogenic.
Conclusions: This large-scale functional study of LDLR variants demonstrates the feasibility and clinical utility of integrating high-throughput functional evidence with high accuracy into variant interpretation. The ability to reclassify previously unresolved VUS represents a major step forward in reducing diagnostic uncertainty in FH. The PerMedFH project paves the way for a personalised medicine approach in FH, improving diagnostic precision, and ultimately enhancing patient care and cardiovascular outcomes.