RESUMEN

In recent years, there has been increasing recognition of the public health significance of the spectrum of TB disease presentation, and the existing classification systems of asymptomatic infection and symptomatic TB have been limited in terms of explanatory power. Accordingly, in 2022-2023, a new International Consensus framework for Early TB (ICE-TB) was developed, categorising the spectrum of TB infection and disease into five states based on the presence or absence of macroscopic pathology, host infectiousness, and symptoms and signs.We used the ICE-TB framework to re-analyse existing notification data for 2022 within a low-incidence setting to explore the potential utility and future challenges for its public health application.Existing notification data were sufficient to allow substantial reclassification of currently recognised active disease states, but did not systematically capture Mycobacterium tuberculosis infection or subclinical TB. Fifty percent of existing TB notifications would be classified as 'Clinical, infectious', with the potential need to consider further subclassification.Our exploration highlighted limitations in existing classification systems and diagnostic approaches and should encourage researchers and programmatic implementers to emphasise person-centred and programmatic needs in the development of new tools for TB management..

Asunto(s)

Consenso , Salud Pública , Tuberculosis , Humanos , Incidencia , Tuberculosis/epidemiología , Tuberculosis/diagnóstico , Mycobacterium tuberculosis/aislamiento & purificación , Notificación de Enfermedades

RESUMEN

BACKGROUND: TB control requires the understanding and disruption of TB transmission. We describe prevalence, incidence and risk factors associated with childhood TB infection in Cape Town, South Africa. METHODS: We report cross-sectional baseline and prospective incidence data from a large trial among primary school children living in high TB burden communities. Prevalent infection was defined as QuantiFERON™-TB Gold Plus (QFT-Plus) positivity as assessed at baseline. Subsequent conversion to QFT-Plus positivity was measured 3 years later among those QFT-Plus-negative at baseline. Multivariable logistic regression models examined factors associated with TB infection. RESULTS: QuantiFERON-positivity at baseline (prevalence: 22.6%, 95% CI 20.9-24.4), was independently associated with increasing age (aOR 1.24 per additional year, 95% CI 1.15-1.34) and household exposure to TB during the participant's lifetime (aOR 1.87, 95% CI 1.46-2.40). QFT-Plus conversion at year 3 (12.2%, 95% CI 10.5-14.0; annual infection rate: 3.95%) was associated with household exposure to an index TB case (aOR 2.74, 95% CI 1.05-7.18). CONCLUSION: Rates of QFT-diagnosed TB infection remain high in this population. The strong association with household TB exposure reinforces the importance of contact tracing, preventative treatment and early treatment of infectious disease to reduce community transmission.

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CONTEXTE: La lutte contre la TB nécessite la compréhension et la perturbation de la transmission de la TB. Nous décrivons la prévalence, l'incidence et les facteurs de risque associés à l'infection tuberculeuse infantile au Cap, en Afrique du Sud. MÉTHODES: Nous rapportons des données transversales de référence et d'incidence prospective provenant d'un vaste essai mené auprès d'enfants d'écoles primaires vivant dans des communautés à forte charge de morbidité tuberculeuse. La prévalence de l'infection a été définie comme la positivité au QuantiFERON™-TB Gold Plus (QFT-Plus) telle qu'évaluée au départ. La conversion subséquente en QFT-Plus positif a été mesurée 3 ans plus tard chez les QFT-Plus négatifs au départ. Des modèles de régression logistique multivariée ont examiné les facteurs associés à l'infection tuberculeuse. RÉSULTATS: La positivité QuantiFERON-au départ (prévalence : 22,6%, IC à 95% 20,9­24,4), était indépendamment associée à l'augmentation de l'âge (aOR 1,24 par année supplémentaire, IC à 95% 1,15­1,34) et à l'exposition du ménage à la TB au cours de la vie du participant (aOR 1,87 ; IC à 95% 1,46­2,40). La conversion QFT-Plus à l'année 3 (12,2%, IC à 95% 10,5­14,0 ; taux d'infection annuel : 3,95%) était associée à l'exposition du ménage à un cas de tuberculose index (aOR 2,74 ; IC à 95% 1,05­7,18). CONCLUSION: Les taux d'infection tuberculeuse diagnostiquée par QFT restent élevés dans cette population. La forte association avec l'exposition à la TB dans les ménages renforce l'importance de la recherche des contacts, du traitement préventif et du traitement précoce des maladies infectieuses pour réduire la transmission communautaire.

RESUMEN

SETTING: Glasgow, Scotland, UK. BACKGROUND: Paradoxical reactions in tuberculosis (TB) are a notable example of our incomplete understanding of host-pathogen interactions during anti-tuberculosis treatment. OBJECTIVES: To determine risk factors for a TB paradoxical reaction, and specifically to assess for an independent association with vitamin D use. DESIGN: Consecutive human immunodeficiency virus (HIV) negative adult patients treated for extra-pulmonary TB were identified from an Extended Surveillance of Mycobacterial Infections database. In our setting, vitamin D was variably prescribed for newly diagnosed TB patients. A previously published definition of paradoxical TB reaction was retrospectively applied to, and data on all previously described risk factors were extracted from, centralised electronic patient records. The association with vitamin D use was assessed using multivariate logistic regression. RESULTS: Of the 249 patients included, most had TB adenopathy; 222/249 had microbiologically and/or histologically confirmed TB. Vitamin D was prescribed for 57/249 (23%) patients; 37/249 (15%) were classified as having paradoxical reactions. Younger age, acid-fast bacilli-positive invasive samples, multiple disease sites, lower lymphocyte count and vitamin D use were found to be independent risk factors. CONCLUSION: We speculate that vitamin D-mediated signalling of pro-inflammatory innate immune cells, along with high antigenic load, may mediate paradoxical reactions in anti-tuberculosis treatment.

Asunto(s)

Antituberculosos/uso terapéutico , Tuberculosis Ganglionar/tratamiento farmacológico , Tuberculosis/tratamiento farmacológico , Vitamina D/administración & dosificación , Adulto , Factores de Edad , Estudios de Cohortes , Femenino , Interacciones Huésped-Patógeno , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo , Escocia , Resultado del Tratamiento , Tuberculosis/microbiología , Tuberculosis Ganglionar/microbiología