Avances en tuberculosis en el 54° Congreso Chileno de enfermedades respiratorias. 3a parte: Prevención de la tuberculosis activa mediante el tratamiento de la tuberculosis latente / Advances in tuberculosis at the 54th Chilean Congress of Respiratory Diseases. Part 3: prevention of active tuberculosis by treating latent tuberculosis

La infección tuberculosa latente (ITL) es un estado asintomático de la infección por Mycobacterium tuberculosis incapaz de transmitir la infección a otros, pero con el potencial de originar una tuberculosis (TBC) activa en el infectado, especialmente ante la presencia de factores de riesgo inmunológico. Es importante en personas de riesgo de desarrollar TBC reconocer la ITL utilizando test como la reacción a la tuberculina (PPD o TST) y los ensayos de liberación de Interferón-γ (IGRAs). Sin embargo, estos tests tienen limitaciones en su capacidad de predicción de riesgo de evolución de infección a enfermedad lo que conlleva a tener que tratar muchas personas para evitar algún caso de enfermedad. Nuevos tests se encuentran en desarrollo para mejorar la sensibilidad de reconocimiento de la ITL, distinguir infecciones recientes (que tienen el mayor riesgo de progresión a enfermedad) e incluso con la capacidad de detectar enfermedad subclínica o inicial. Para reducir la probabilidad de enfermar por TBC se utilizan tratamientos preventivos con fármacos, pero la cobertura mundial de esta terapia es reducida y la adherencia a terapias auto-administradas, como en el caso del uso de isoniazida diaria oral, es también baja. Otro problema de esta terapia son los riesgos de reacciones adversas (hepatitis, erupciones cutáneas) aunque no frecuentes. La recomendación de terapia actual de la ITL incluye el uso de rifamicinas y sus derivados. La asociación de isoniazida con rifapentina en una dosis semanal durante tres meses, administrada bajo supervisión, es la terapia de primera línea para mayores de 2 años, mostrando menos riesgo de hepatotoxicidad y mayor adherencia.

Latent Tuberculosis infection (LTBI) is the asymptomatic state of infection caused by Mycobacterium tuberculosis. Although untransmissible, LTBI can progress to active tuberculosis (TB), especially in people with immune risk factors. It is important to recognize LTBI in people at risk of developing TB; tuberculin skin test (PPD or TST) or interferon-γ release assays (IGRAs) are current diagnostic tests. However, these tests have limitations in their ability to predict subjects who will evolve from infection to disease; consequently, a large number of people with LTBI need treatment to avoid a reduced number of future TB disease cases. Newer tests are under development to improve the sensitivity in recognizing LTBI, distinguish recent infections with highest risk of progression to disease, and even be able to detect initial subclinical disease. Antimicrobial preventive treatment effectively reduces the probability of getting sick with TB, but worldwide availability of TB preventive therapy is limited, and adherence to self-administered therapies, as in the case of the use of daily oral isoniazid, is low. Adverse reactions risk (hepatitis, skin rash) although infrequent, is another problem with these therapies. Currently, LTBI management guidelines include regimens with use of rifamycins and their derivatives. The combination of isoniazid and rifapentine in a weekly dose for three months administered under supervision is the first line choice for LTBI therapy in those over 2 years of age, showing less hepatoxicity risk and greater adherence.

Otomastoiditis por mycobacterium tuberculosis: un diagnóstico desafiante / Tuberculous otomastoiditis: a challenging diagnosis

RESUMEN La otomastoiditis tuberculosa es una presentación extremadamente rara de la forma extrapulmonar de la enfermedad y puede ser difícil llegar a su diagnóstico. Presentamos el caso de una paciente de 35 años con otomastoiditis tuberculosa bilateral acompañado de vértigo, hipoacusia mixta bilateral y paresia del nervio facial bilateral, como debut de una tuberculosis. Cultivos de Mycobacterium tuberculosis (MTB) y prueba de reacción en cadena de la polimerasa (PCR) de otorrea fueron inicialmente negativos. La tomografía computarizada de oídos y resonancia magnética mostraron cambios inflamatorios otomastoídeos bilaterales sin evidencia de erosión ósea ni extensión a partes blandas. Se realizó una mastoidotomía, las muestras del tejido obtenido evidenciaron osteomielitis crónica, bacterias ácido-alcohol resistentes y PCR positiva para MTB. La paciente recibió tratamiento con drogas antituberculosas durante 12 meses logrando una recuperación completa de la otalgia y vértigo, y mejoría parcial de audición y paresia facial. En resumen, los hallazgos clínicos e imagenológicos de la otomastoiditis tuberculosa son inespecíficos por lo cual se requiere de un alto índice de sospecha clínica para lograr el diagnóstico adecuado e iniciar el tratamiento de la infección subyacente.

ABSTRACT Tuberculous otomastoiditis is an extremely rare form of extrapulmonary disease that can be easily misdiagnosed. We hereby report the case of a previously healthy 35-yearold female with bilateral tuberculous otomastoiditis associated with vertigo, bilateral mixed hearing loss, and bilateral facial nerve palsy as the initial clinical presentation. Repeated Mycobacterium tuberculosis (MTB) culture and molecular testing of otorrhea aspirates were initially negative. High-resolution temporal bone computed tomography and magnetic resonance imaging showed partial opacification of the mastoid air cells without signs of bone erosion. A mastoidotomy was performed with mastoid tissue showing chronic osteomyelitis, positivity in acid-fast staining and MTB PCR. The patient was treated with a 12 month antituberculous treatment, with complete recovery of otalgia and vertigo, and improvement in hearing levels and facial nerve palsy. In summary, clinical and imaging findings for tuberculous otomastoiditis are non-specific, hence a high degree of suspicion is required in order to diagnose and promptly treat the underlying infection.

Metodología de adaptación de una guía clínica para el manejo de pacientes adultos con neumonía adquirida en la comunidad en una red de salud privada / The adaptation methodology of a guideline for the management of adults with community-acquired pneumonia

Background: Clinical practice guidelines (CPG) are widely used as tools for improving quality of health care. Guidelines developed elsewhere, can be adapted using a valid and systematic process. Aim: To describe the methodology used in the process of adaptation of a guideline for the management of adults with community-acquired pneumonia (CAP) in a private health care organization. Material and Methods: We used the ADAPTE framework involving three main phases. At the set-up phase a guideline adaptation group integrated by medical specialists from different disciplines, a methodologist and a nurse coordinator was formed. At the adaptation phase, the specific clinical questions to be addressed by the guidelines were identified. Results: Twenty five guidelines were initially retrieved. After their assessment, the number was reduced to only three. Recommendations from these guidelines were 'mapped' and focused searches were carried out where 'evidence gaps' were identified. An initial draft was written and revised by the adaptation group. At the finalization phase, the external review of the guideline was carried out and a process for the regular review and update of the adapted guideline was defined. Conclusions: We developed a guideline for the management of adults with CAP, adapted to the local context of our health care system, using guidelines developed elsewhere. This guideline creation method can be an efficient means of saving professional resources.