Resumen Se presenta el caso de un paciente masculino de 60 años de edad, tabaquista de 135 paquetes/año con síntomas respiratorios agudos e infiltrados pulmonares bilaterales, en contexto de pandemia y cuyo diagnostico definitivo fue adenocarcinoma de pulmón, presentando durante su evolución neumotórax espontaneo. Arribar al diagnóstico definitivo puede llegar a ser un gran desafío por la similitud en la presentación radiológica como en los síntomas respiratorios atribuibles a COVID-19 y la dificultad para llevar a cabo los procedimientos diagnósticos. La sospecha de una neoplasia de pulmón, cuando se acompaña de un neumotórax debe incluirse dentro de los diagnósticos diferenciales, aunque se trate de una entidad poco frecuente.

Abstract We present the case of a 60-year-old male, a 135-pack/year smoker with acute respiratory symptoms and bilateral pulmonary infiltrates, in the context of a pandemic and whose definitive diagnosis was lung adenocarcinoma, presenting during his evolution spontaneous pneumothorax. Arriving at the definitive diagnosis can become a great challenge due to the similarity in the radiological presentation and in the respiratory symptoms attributable to COVID-19 and the difficulty in carrying out the diagnostic procedures. The suspicion of a lung neoplasm, when accompanied by a pneumothorax, should be included in the differential diagnoses, although it is a rare entity.

Crystalline cellulose nanofibers are obtained from the bark of Cereus Forbesii, a cactus native to the arid areas of South America. The obtaining of cellulose nanofibers was carried out in several steps: pretreatment of the raw material, elimination of hemicellulose and lignin to obtain cellulose, and an acid hydrolysis of cellulose to obtain crystalline cellulose nanofibers. The cellulose nanofibers obtained have a crystallinity index of 82% and a nanofiber diameter of 18 nm. An average crystallite size of 6 nm was calculated for the crystalline domains that form cellulose nanofibers. The high crystallinity of the obtained cellulose nanofibers makes the sample very homogeneous and decomposes in a relatively narrow temperature range (between 290°C and 375°C). The complete degradation of crystalline cellulose polymer chains takes place between 375°C and 600°C. The morphological and structural studies are carried out by scanning electron microscopy of field emission, infrared spectrometry with Fourier transform, and powder X-ray diffraction. The thermal stability of the samples is determined by thermogravimetric analysis.

Hypereosinophilic Syndrome (HES) is a heterogeneous group of diseases, which are characterized by a marked eosinophilia in blood, greater than 1500 cells / mm³ over six months duration, associated with damage to multiple organs, eosinophilic infiltration, or release mediators. Eosinophilia is a common finding in clinical practice, but when levels of eosinophils are elevated can be a diagnostic challenge. We report the case of a patient with a history of recurrent facial angioedema, she consulted for some productive cough, dyspnea and toracodinia. The laboratory showed severe respiratory failure with eosinophilia. Chest radiography confirmed pulmonary infiltrates and pleural effusion. The patient underwent several complementary studies that guided us to the diagnosis of Idiopathic Hypereosinophilic Syndrome due to absence of secondary causes and finding of eosinophils in various tissues such as bone marrow, pleural fluid, and bronchoalveolar lavage. Good response to treatment with systemic corticosteroids was observed, achieving complete remission of the disease.

El Síndrome Hipereosinofílico (SHE) constituye un grupo heterogéneo de enfermedades, que se caracterizan por una marcada eosinofilia en sangre, mayor a 1500 cel/mm³ de más de seis meses de evolución, asociado a daño de múltiples órganos, por infiltración eosinofílica ó liberación de mediadores. La eosinofilia es un hallazgo común en la práctica clínica, pero cuando se encuentran valores elevados de eosinófilos constituye un desafío diagnóstico. Presentamos el caso clínico de una paciente con antecedente de angioedema facial recurrente que consultó por tos poco productiva, toracodinia y disnea. El laboratorio mostró insuficiencia respiratoria con eosinofilia severa. La radiografía de tórax confirmó infiltrados pulmonares y derrame pleural. La paciente fue sometida a varios estudios complementarios, que nos orientaron hacia el diagnóstico de Síndrome Hipereosinofílico Idiopático, debido a la ausencia de causas secundarias y al hallazgo de eosinófilos en varios tejidos como médula ósea, líquido pleural, y lavado broncoalveolar. Se observó buena respuesta al tratamiento con corticoides sistémicos, logrando remisión completa de la enfermedad.