Pulmonary fibrosis - Research Paper Example

Pulmonary fibrosis is a factor that categorizes various forms of acute and chronic interstitial lung disease. The American Thoracic Society and the European Respiratory Society classify Interstitial Pulmonary Diseases into seven distinct categories of Interstitial Lung Disease (ILD), “idiopathic pulmonary fibrosis (IPF), nonspecific interstitial pneumonia (NSIP), acute interstitial pneumonitis (AIP), respiratory bronchiolitis-associated ILD, desquamative interstitial pneumonia, cryptogenic organizing pneumonia (COP) and lymphocyte interstitial pneumonia” (Lovgren, 2007).

The history of pulmonary fibrosis is deeply linked with Idiopathic Pulmonary Fibrosis (IPF). IPF is a subset of ILD. IPD is a form of chronic pulmonary fibrosis where the etiology of the disease is unknown. IPF was first described by Hamman and Rich in 1935 at the John Hopkins Hospital. Later this was found to be a case of acute interstitial pneumonia. The Liebow classifications in 1960 marked a new era for interstitial lung diseases. It was not until 1980 that the importance of growth factors was taken into consideration.

This led to understanding of ILD through abnormal wound healing rather than inflammation. Anatomy of the systems involved The foremost system involved and affected by pulmonary fibrosis is the respiratory system. . The alveoli are sac like structures that are present at the terminal end of the bronchioles. Alveoli are highly vascularized and are responsible for gaseous exchange. The alveolar wall is about 0.5µm in thickness. It consist of four layers of cells which are the squamous cells of alveoli, basement membrane of alveoli, basement membrane of the capillaries and squamous cells of capillaries.

The intersitium is the space between the alveolar epithelium and capillary endothelium. It is found to be thin on one side of the capillary, where it consists of basement membranes of the capillary and alveoli. The mechanical strength of the thin side of the blood gas barrier comes from the type IV collagen present in the interstitium. The opposite side of the capillary has an interstitium that is wider and consists of type I collagen with fibroblasts and pericytes. Pulmonary fibrosis affects the intersitium of the alveoli.

The disease involves thickening of this interstitium through collagen. In the initial stages, an increased number of lymphocytes and plasma cells are found within the area. These cells are later accompanied by fibroblasts that lay down thick collagen bundles. The functioning of the heart is closely related to respiratory system. The affects of pulmonary fibrosis are evident on the working of the cardiovascular system. Since the tissue is scarred, the heart muscle works harder to pump the same volume of blood through the lungs.

As fibrosis continues the risks of heart failure increase. Causes for the disease Pulmonary fibrosis may be caused by a number of factors, the foremost of which are inhalation of environmental agents and results of auto immune disorders. The more common reasons