Surfactant in SARS-CoV-2 ­ a therapeutic option based on underlying lung cell damage? / Surfactante em SARS-CoV-2 ­ uma opção terapêutica baseada no dano celular subjacente aos pneumócitos?

Introduction: the severe acute respiratory syndrome ­ coronavirus 2 (SARS Cov-2), leads to a diffuse alveolar deterioration due infection of type II pneumocytes. The type II pneumocytes are involved in synthesis and secretion of pulmonary surfactant in pulmonary alveoli. Objective: the purpose of this study is to discuss the indication of surfactant replacement as a potential adjunctive treatment modality for SARS CoV-2, similarly treatment to neonatal respiratory distress syndrome. Methodology: we argue that SARS can be triggered by surfactant deficiency secondary to production deficiency determined by type 2 pneumocyte injuries. In this sense, we carried out a bibliographic review. Conclusion: thus, the replacement of human surfactant could be a potential treatment modality for SARS CoV-2, in the same way that it is indicated for the treatment of neonatal respiratory distress syndrome.

Introdução: a síndrome respiratória aguda grave ­ coronavírus 2 (SARS Cov-2), leva a uma deterioração alveolar difusa devido à infecção do pneumócitos tipo II. Os pneumócitos tipo II estão envolvidos na síntese e secreção de surfactante pulmonar nos alvéolos pulmonares. Objetivo: o objetivo deste estudo é discutir a indicação de reposição de surfactante como uma potencial modalidade de tratamento adjuvante para SARS CoV-2, similarmente ao tratamento da síndrome do desconforto respiratório neonatal. Metodologia: argumentamos que a SARS pode ser desencadeada pela deficiência de surfactante, secundária à deficiência da sua produção determinada por lesões de pneumócitos tipo 2. Nesse sentido, realizamos uma revisão bibliográfica. Conclusão: o uso de surfactante humana pode ser uma potencial modalidade de tratamento para a SARS CoV-2, da mesma forma que é indicada para o tratamento da síndrome do desconforto respiratório neonatal.

Clinical and pathological aspects of idiopathic pulmonary fibrosis in cats / Aspectos clínicos e patológicos em felinos com fibrose pulmonar idiopática

Interstitial lung diseases are a group of diffuse parenchymal lung diseases that include interstitial lung fibrosis. The aim of this study is to characterize the clinical and pathological findings of idiopathic pulmonary fibrosis in three cats and to investigate possible etiological agents through bacteriological and mycological exams and immunohistochemistry. All three cats were female and aged from 10 to 14 years old, they presented with a clinical history of weight loss and dyspnea. The radiographic changes were similar in all cats and included increased pulmonary radiopacity with a mixed bronchointerstitial pattern progressing to an alveolar pattern. Two cats died during lung biopsy procedures. At necropsy, the lesions were limited to the pulmonary parenchyma and were firm, hypocrepitant with a multinodular appearance on the pleural surface; they failed to completely collapse when the thorax was opened. In the pleural region, there were multifocal star-shaped scarring lesions, with parenchymal retraction. Microscopically, all three cats had multifocal-to-coalescing fibrosis, type II pneumocyte hyperplasia, hypertrophy or hyperplasia of the smooth muscle tissue of terminal bronchioles and an accumulation of macrophages within the alveolar spaces. There was no growth on bacteriological or mycological cultures, and the immunohistochemical evaluations for the presence of viral etiological agents (FIV, FeLV, FCoV, FCV and FHV-1) were also negative.(AU)

As enfermidades pulmonares intersticiais são um grupo de doenças difusas do parênquima pulmonar, nas quais a fibrose pulmonar está incluída. O objetivo deste trabalho é caracterizar os achados clínicos e patológicos da fibrose pulmonar idiopática em três gatas, e avaliar possíveis agentes etiológicos através dos exames bacteriológicos, micológicos e imuno-histoquímicos. As três gatas tinham entre 10 e 14 anos de idade e histórico clínico de emagrecimento e dispneia. As alterações radiográficas observadas foram similares, com aumento de radiopacidade difuso dos campos pulmonares de padrão misto broncointersticial e eventualmente alveolar. Dois felinos morreram durante procedimento de biópsia pulmonar. No exame de necropsia as lesões eram exclusivas no parênquima pulmonar os quais estavam firmes, hipocreptantes, com aspecto levemente multinodular em superfície pleural e não colapsaram após a abertura da cavidade torácica. Em região pleural havia lesões cicatriciais de aspecto estrelar multifocais, com retração do parênquima. Microscopicamente, todos os gatos apresentaram fibrose multifocal a coalescente, hiperplasia dos pneumócitos do tipo II e hiperplasia e hipertrofia do músculo liso de bronquíolos terminais e acúmulo de macrófagos no interior de espaços alveolares. Não houve crescimento nas culturas bacteriana e micológica, e os exames de imuno-histoquímica para avaliação de possíveis agentes virais (FIV, FeLV, FCoV, FCV e FHV-1) foram negativos em todos os felinos.(AU)

Dispneia expiratória restritiva em um gato com fibrose pulmonar idiopática: relato de caso / Restrictive expiratory dyspnea in a cat with idiopathic pulmonary fibrosis: case report

As doenças pulmonares intersticiais constituem um grupo de doenças difusas do parênquima pulmonar, no qual a fibrose pulmonar intersticial está incluída. Histologicamente, esta se caracteriza por hiperplasia de pneumócitos tipo II, hiperplasia ou hipertrofia de músculo liso e fibrose. Embora a patogenia da fibrose pulmonar intersticial não esteja bem elucidada, devido às semelhanças microscópicas encontradas nos pneumócitos tipo II em felinos e na forma familiar da doença em humanos, acredita-se que haja caráter genético para o seu desenvolvimento. Os sinais clínicos frequentemente relatados incluem desconforto respiratório, cianose, letargia e perda de peso. Devido ao caráter progressivo e à ausência de tratamento específico, a doença apresenta prognóstico desfavorável. Foi atendida uma gata de 12 anos de idade, com histórico de dispneia há 20 dias. Ao exame clínico, o animal apresentou dispneia expiratória restritiva, crepitação à ausculta torácica e foi visualizado padrão intersticial ao exame radiográfico do tórax. A paciente foi submetida à punção com agulha fina de tecido pulmonar e veio a óbito algumas horas após o procedimento, apresentando insuficiência respiratória aguda. No exame histológico do tecido pulmonar, foi verificada a ocorrência de fibrose pulmonar idiopática. O objetivo do presente trabalho é relatar um caso de dispneia expiratória restritiva em um felino doméstico devido à fibrose pulmonar idiopática, já que, segundo o conhecimento dos autores, não há nenhum relato da ocorrência da doença no país.(AU)

Interstitial lung diseases are a group of diffuse parenchymal lung diseases in which interstitial lung fibrosis is included. Histologically, it is characterized by type II pneumocyte hyperplasia, hypertrophy or hyperplasia of smooth tissue and fibrosis. Although the pathogenesis of interstitial lung fibrosis has not been elucidated, due to the microscopic similarities found in type II pneumocytes in cats and familial form of the disease in humans, it is believed that there is a genetic trait for development. The frequently reported clinical signs include respiratory distress, cyanosis, lethargy, and weight loss. Due to the progressive nature and the absence of specific treatment, the disease has a poor prognosis. A 12-year-old cat with dyspnea for 20 days was assisted. The animal underwent fine needle aspiration of lung tissue and died few hours after the procedure, with acute respiratory failure. Upon histological examination of lung tissue, the occurrence of idiopathic pulmonary fibrosis was found. The aim of this study is to report a case of restrictive expiratory dyspnea in a domestic feline due to idiopathic pulmonary fibrosis, because, according to our knowledge, there is no report on the occurrence of the disease in our country.(AU)

A Case of Alveolar Adenoma Involving Multiple Lung Nodules / 대한내과학회지

Alveolar adenoma is a very rare benign intraparenchymal lung tumor originating from type II pneumocytes. It can be mistaken for other benign tumors or lung cancer in radiological images. It is especially difficult to distinguish alveolar adenoma from sclerosing hemangioma. A small aspiration biopsy specimen, such as with percutaneous needle aspiration, is insufficient for a pathological diagnosis. Surgical resection is the only method by which a pathological diagnosis can be made and the disease treated. An alveolar adenoma presenting as multiple nodules is very rare and has to our knowledge not been reported in Korea previously. Here, we report a case of alveolar adenoma in multiple nodules in a 57-year-old female and review the literature.

The Effect of Corticosteroid on the Fetal Pulmonary Maturation of Rats with Streptozotocin-Induced Diabetes

The effect of dexamethasone of the maturation of the fetal lungs of rats with streptozotocin-induced diabetes was studied morphologically and biochemically. By light and electron microscopy there was little difference in fetal pulmonary maturation between the untreated control group and the untreated diabetic group, but when both groups were treated with dexamethasone the fetuses showed accelerated pulmonary maturation, approximately one day earlier with an increase of air spaces per unit area and an earlier appearance of type II pneumocytes. The number of osmiophilic inclusion bodies per alveolus and per type II pneumocyte, and the lecithin/sphingomyelin ratio in amniotic fluid increased markedly and they were statistically significant in both groups injected with dexamethasone, but were decreased in the untreated diabetic group, though only the L/S ratio of the animals of the 19th day gestation was statistically significant. Phosphatidylglycerol was present in the amniotic fluid of the groups injected with dexamethasone one day earlier than the untreated control and the untreated diabetic groups. However, the intensity of phosphatidylglycerol tended to be lower in the untreated diabetic group. It is concluded that the prenatal administration of dexamethasone to the diabetic pregnant rats will accelerate fetal pulmonary maturation morphologically and promote the synthesis of surfactant biochemically.