Respiratory ILD Flashcards
define ILD/ DPLD
group of lung diseases affecting the interstitium (alveolar epithelium, pulmonary capillary endothelium, basement membrane, perivascular and perilymphatic tissue). ILDs interfere with gas transfer. They cause a restrictive pattern. Symptoms: breathlessness, dry cough. ILD can be acute/ episodic/ chronic (chronic can be part of systemic disease/ due to chronic exposure to an agent/ idiopathic)
What are the 4 main categories of ILD?
- ILD of known cause e.g.drugs/ collagen vascular disease
- Idiopathic Interstitial Pneumonia (IIP)
- Granulomatous ILDs e.g. sarcoidosis, EAA
- Other forms of ILD e.g. LAM
What are the 8 types of Idiopathic interstitial pneumonia?
- Idiopathic pulmonary fibrosis
- Desquamative interstitial pneumonia
- Acute interstitial pneumonia
- non-specific interstitial pneumonia
- Lymphocytic interstitial pneumonia
- Cryptogenic organising pneumonia
- IIP other than IPF
Collagen Vascular disease
A group of disease which affect the connective tissue (can cause ILD of known origin)
Idiopathic pulmonary fibrosis
a chronic and ultimately fatal disease characterised by a progressive worsening dyspnea. Poor prognosis.
Desquamative interstitial pneumonia
Form of IPF featuring elevated levels of macrophages. Name is derived from former belief that these macrophages were pneumocytes (alveolar cells) that had been desquamated. This disease is associated with people who have smoking history.
Respiratory bronchiolitis interstitial lung disease
Associated with smoking.
This is a histological finding, not a pathological description. Appearance is similar to that of desquamative interstitial pneumonia
Acute interstitial pneumonia
Rare, severe, usually affects otherwise health individuals. No known cause or cure, often characterised as an ILD, but is also a form of ARDS
Cryptogenic organising pneumonia (AKA bronchiolitis obliterans organising pneumonia (BOOP))
inflammation of the bronchioles and surrounding tissue of the lugs. Often a complication of existing inflammatory disease e.g. rheumatoid arthritis. “Organising” refers to unresolved pneumonia (the alveolar exudate persists and eventually undergoes fibrosis). That phase of resolution/ remodelling following bacterial infections is commonly referred to as organising pneumonia.
Non-specific interstitial pneumonia (NSIP)
2 different disease patterns with different prognoses: cellular, and fibrosing. Cellular pattern has chronic inflammation and minimal fibrosis. Fibrosing pattern has interstitial fibrosis with various inflammation levels. Both patterns are uniform and lack the prominent fibroblastic foci that are found in other types of IIP.
Lymphocytic interstitial pneumonia
A syndrome secondary to autoimmune and other lymphoproliferative disorders
Sarcoidosis
Disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. Granulomas are non-caseating - unknown aetiology (but probably infective agent in susceptible individual, imbalance of immune system with type 4 hypersensitivity). LESS common in smokers. There is genetic pre-disposition for sarcoidosis.
LAM (Lymphangioleiomyomatosis)
Rare, progressive and systemic disease that results in cystic lung destruction. Mostly affects women of child-bearing age. Lung destruction is consequence of diffuse infiltrationof neoplastic smooth muscle-like cells, which invade all lung structures including lymphatics, airway walls, blood vessels, and interstitial spaces. Consequences of obstruction of vessels and airways include chylous fluid accumulations, haemoptysis, airflow obstruction, pneumothorax.
Clinical features of acute sarcoidosis
-erythema nodosum
-bilateral hilar lymphadenopathy
-arthritis
-uveitis
-parotitis
-fever
The disease often settles in a couple of months without treatment
Clinical features of chronic sarcoidosis
- lung infiltrates (alveolitis)
- skin infiltrations
- peripheral lymphadenopathy
- hypercalcaemia
- other organs: renal, myocardial, neurological, hepatitis, splenomegaly
Key difference between TB and sarcoidosis? (Both are granulomatous).
TB is infective, unlike sarcoidosis