Diffuse parenchymal lung disease (DPLD), also known as interstitial lung disease, refers to a group of lung diseases, affecting the alveolar epithelium, pulmonary capillary endothelium, basement membrane, perivascular and perilymphatic tissues. The term DPLD is used to distinguish these diseases from obstructive airways diseases. Most types of DPLD involve fibrosis, but this is not essential; indeed fibrosis is often a later feature. Hence the term pulmonary fibrosis has fallen out of favor. The heart and lungs (from an older edition of Grays Anatomy) The lung is an organ belonging to the respiratory system and interfacing to the circulatory system of air-breathing vertebrates. ... Detailed drawing of the alveoli from Grays Anatomy The alveolus (plural:alveoli), tiny hollow sacs which are continuous with the airways, are the sites of gas exchange with the blood. ... In zootomy, epithelium is a tissue composed of a layer of cells. ... Capillaries are the smallest of a bodys blood vessels. ... The endothelium is the layer of thin, flat cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. ... Fibrosis is the formation or development of excess fibrous connective tissue in an organ or tissue as a reparative or reactive process, as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue. ...

Causes

DPLD may be classified according to the cause: -

1. Inhaled substances

• Inorganic
  • Silica
  • Asbestos
  • Beryllium
• Organic
  • Hypersensitivity pneumonitis

2. Drug induced Inorganic chemistry is the branch of chemistry concerned with the properties and reactions of inorganic compounds. ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... Asbestos (Greek a-, not; sbestos, extinguishable) is a group of fibrous metamorphic minerals. ... General Name, Symbol, Number Beryllium, Be, 4 Series Alkaline earth metals Group, Period, Block 2 (IIA), 2, s Density, Hardness 1848 kg/m3, 5. ... Organic has several meanings and related topics. ... Many drugs are provided in tablet form. ...

• Antibiotics
• Chemotherapeutic drugs
• Antiarrhythmic drugs

3. Connective tissue disease An antibiotic is a drug that kills or slows the growth of bacteria. ... Chemotherapy (pronounced keem-o-therapy) is the use of certain drugs to treat disease, as distinct from other forms of treatment, such as surgery. ... Antiarrhythmic agents are a group of pharmaceuticals that are used to suppress fast rhythms of the heart (cardiac arrhythmias), such as atrial fibrillation, atrial flutter, ventricular tachycardia, and ventricular fibrillation. ...

• Systemic sclerosis
• Dermatomyositis
• Systemic lupus erythematosus
• Rheumatoid arthritis

4. Infection Scleroderma is a rare, chronic disease characterized by excessive deposits of collagen. ... X-Ray of the knee in a patient with dermatomyositis. ... Lupus erythematosus (also known as systemic lupus erythematosus - SLE) is an autoimmune disorder in which antibodies are created against the patients own DNA. It classically presents with a butterfly-shaped malar rash, causing a wolf-like appearance (Lupus is Latin for wolf). ... Rheumatoid arthritis (RA) is a chronic, inflammatory autoimmune disorder that causes the immune system to attack the joints. ... Infection is also the title of an episode of the television series Babylon 5; see Infection (Babylon 5). ...

• Atypical pneumonia
• Pneumocystis carinii pneumonia
• Tuberculosis

5. Idiopathic Pneumonia (the ancient Greek word for lungs) is defined as an infection involving the alveoli of the lungs. ... Pneumocystis carinii pneumonia (PCP) is a form of pneumonia which is caused by a microorganism called Pneumocystis carinii (It has been proposed that the organism be renamed Pneumocystis jiroveci). ... Tuberculous lungs show up on an X-ray image Tuberculosis is an infection with the bacterium Mycobacterium tuberculosis, which most commonly affects the lungs (pulmonary TB) but can also affect the central nervous system (meningitis), lymphatic system, circulatory system (miliary TB), genitourinary system, bones and joints. ... Idiopathic is a medical adjective that indicates that a recognized cause has not yet been established. ...

• Sarcoidosis
• Idiopathic pulmonary fibrosis

6. Malignancy Sarcoidosis is an uncommon autoimmune disorder of unknown cause. ... When normal cells are damaged or old they undergo apoptosis; cancer cells, however, avoid apoptosis. ...

• Lymphangitic carcinomatosis

In medicine, carcinoma is any cancer that arises from epithelial cells. ...

Investigation

Investigation is tailored towards the symptoms and signs. Most patients have blood testing, chest x-ray, pulmonary function testing, and high resolution CT thorax. In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... CAT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around...

Treatment

DPLD is not a single disease, but encompasses many different pathological processes. Hence treatment is different for each disease.

If a specific occupational exposure cause is found, the person should avoid that environment. If a drug cause is suspected, that drug should be discontinued.

Many idiopathic and connective tissue-based causes of DPLD are treated with prednisolone. Some patients respond to immunosuppressant treatment. Patients with hypoxemia may be given supplemental oxygen. Prednisolone is a synthetic corticosteroid drug which is usually taken orally and can be used for a large number of different conditions. ... Immunosuppression is the medical suppression of the immune system. ... General Name, Symbol, Number Oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16 (VIA), 2, p Density, Hardness 1. ...

External Links

• What is Pulmonary Fibrosis? (http://www.pulmonaryfibrosis.org/ipf.htm)