Chronic obstructive pulmonary disease (COPD), a major cause of mortality and morbidity worldwide, is considered an archetypical disease of innate immunity, where inhaled particles and gases trigger an inflammatory response, favoring tissue proliferation in small airways and tissue destruction in lung parenchyma, in addition to the recruitment of immune cells to these compartments. Although cigarette smoking is still considered the main risk factor for developing COPD, the trend of proposing biomass smoke (BS) exposure as a principal risk factor is gaining importance, as around 3 billion people worldwide are exposed to this pollutant daily. A considerable amount of evidence has shown the potential of BS as an enhancer of lung inflammation. However, an impairment of some innate immune responses after BS exposure has also been described. Regarding the mechanisms by which biomass smoke alters the innate immune responses, three main classes of cell surface receptors-the TLRs, the scavenger receptors and the transient receptor potential channels-have shown the ability to transduce signals initiated after BS exposure. This article is an updated and comprehensive review of the immunomodulatory effects described after the interaction of BS components with these receptors.

We report a 25-year-old (Rev Med Chile 2013; 141: 922-926)

Approximately 3 million people in the world die every year as a consequence of COPD, which is associated with an abnormal inflammatory response of the lung to noxious particles and gases. This inflammatory pattern causes pathological changes leading to a narrowing of small airways and destruction of lungjordiog82@gmail.com L a enfermedad pulmonar obstructiva crónica (EPOC) es un proceso patológico de alta prevalencia, considerado en la actualidad la cuarta causa de muerte en el mundo y que, se estima, se convertirá en la tercera en el año 2030 1 . En los países de América Latina, 35 de cada 1.000 hospitalizaciones se deben a la EPOC, con un alto coste económico y con rangos de mortalidad intrahospitalaria que van de 6,7% a 29,5% 2 . En Chile, las enfermedades respiratorias constituyen la tercera causa de muerte y, entre ellas, la EPOC ocupa el segundo lugar, representando a 22% de los decesos 3 . Por su parte, el Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (PLATINO) ha reportado que la prevalencia de la EPOC en Santiago de Chile es de 6,3% en la población mayor de 40 años 4 . La EPOC se define como una enfermedad caracterizada por una limitación al flujo aéreo no completamente reversible, progresiva y que se asocia a una respuesta inflamatoria anormal de los pulmones a partículas nocivas o gases 5 . Esta enfermedad comprende tanto los síntomas clínicos de la bronquitis/bronquiolitis crónica como los de la patología derivada del enfisema pulmonar. La confirmación diagnóstica se obtiene al realizar pruebas espirométricas, las cuales permiten determinar la obstrucción del flujo aéreo y el grado de alteración de la función pulmonar a partir del volumen espirado forzado en el primer segundo (VEF 1 ), la capacidad vital forzada (CVF) y la relación de estos dos parámetros clínicos (VEF 1 /CVF) 5 . Se considera al humo del tabaco como el prin-

is a rare interstitial lung disease, of unknown etiology, affecting almost exclusively women. Microscopically, LAM consists of a diffuse proliferation of smooth muscle cells. LAM can occur without evidence of other diseases (sporadic LAM) or in conjunction with tuberous sclerosis complex (TSC). It presents with progressive breathlessness or with recurrent pneumothorax or chylothorax. We report a 33 year-old woman with a history of recurrent pneumothorax. Computed tomography (CT) scans showed numerous thin-walled cysts throughout the lungs, a characteristic finding in LAM. A pulmonary biopsy was compatible with the diagnosis and HMB-45 monoclonal antibodies were positive.