Drugs for Restrictive Lung Diseases and PAH Flashcards
What is the treatment for pneumoconiosis (e.g. silicosis, asbestosis, coal miner’s pneumoconiosis, berylliosis)?
There is no curative treatment for deposited material
Excessive doses of which drugs are known to preceipitate ARDS in susceptible individuals?
Aspirin, cocaine, opioids, phenothiazines, and tricyclic antidepressants
Idiosyncratic rxns can also occur with certain chemotherapeutic agents and with radiologic contrast media.
EtOH abuse increases riks of ARDS d/t other causes (e.g. sepsis, trauma) but doesn’t cuase ARDS
Are drugs for ARDS helpful?
None of the drugs has demonstrated a consistent and unequivocal benefit.
List the various drugs used for ARDS
- B-2 agonist (Albuterol, IV) and Inhaled NO
- preferential vasodilation of pulmonary vessels that perfuse functioning alveoli
- Inhaled prostacyclin (PGI2) - vasodilator
- Corticosteroids - anti-inflammatory
- Dietary oil supplementation - anti-inflammatory action (modulation of arachidonic acid metabolism)
What is NRDS?
Most common cuase of respiratory failure in newborns and the most common cause of death in premature infants. Arises from surfactant deficiency in immature lung tissue leading to **increased surface tension, V/Q mismatch and shunting. **
What is the treatment for NRDS?
- Antenatal corticosteroids to all women at risk of delivery <34 weeks; enhances synthesis and release of surfactant
- Exogenous surfactant is administerd to preterm (<30 weeks) neonates to reduce surface tension.
- Natural products (Poractant alfa, Calfactant and Beractant) are purified animal products rich in surfactant proteins, neutral lipids, and DPPC
What is DDPC?
Primary surface-active component that lowers alveolar surface tension
What is the hallmark of sarcoidosis?
Non-caseating granulomas, which often involve multiple organs
What is the treatment for sarcoidosis and what does it depend on?
Treatment with anti-inflammatory glucocorticoids or immunosuppresive methotrexate depends upon the degree of functional impairement
How do glucocorticoids work?
Binding to glucocorticoid receptors in the nucleus
- Inhibit production of pro-inflammatory cytokines (IL-1B and TNF) while promoting the production of anti-inflammatory cytokines (IL-10) by macrophages and dendritic cells
- Promote apoptosis of macrophages, dendritic cells and T cells, leading to inhibition of immune responses
What are the adverse effects associated wtih chronic corticosteroid use?
- hypothalamic-pituitary-adrenal (HPA) axis suppresion
- osteoporosis
- pancreatitis
- steroid-induced diabetes mellitus
- cataracts
- galucoma
- physcosis
- oral candidiasis (opporutnisitc infections)
- immunosupprssion
- weight gain
- skin atrophy
What are the actions of Methotrexate?
- DHFR inhibition and an antineoplastic action
- Increase in adenosine-mediated immunosuppression via a cAMP increase.
What are the adverse effects of taking methotrexate and what are their implications?
A significant side effect profile means that MTX is NOT front-line therapy for its anti-inflammatory effects.
- Severe (and sometimes fatal) dermatologic rxns
- Brith defects
- Malignant lymphoma
- Increased risk of infection (contraindicated in pts with preexisting immunosuppresion)
- Potentially fatal adverse pulmonary effects (acute or chornic interstital pneuonitis and pulmonary fibrosis)
Is Idiopathic Pulmonary Fibrosis (IPF) a chronic inflammatory disease?
NO! Represents 15% of chronic interstitla lung disease.
Even the most potent antiinflammatory drugs yield little or no therapeutic effect. Some clinicans use response and/or non-response to corticosteroid treatment as a differential diagnosis from other lung inflammatory fibrotic diseases.
Explain the pathogenesis of IPF
Altered mesenchymal cell phenotype and blockade of apoptosis gives rise to an altered stromal cell population and the activated epithelium release a series of profibrogenic factors (TGF-B and PDGF) which interact wtih deposited matrix at the site of abnormal repair. This creates a new microenviornment in patchy areas (other areas remain normal in structure and envrionment) of the lung and can give rise to remodeling of the blood vessel walls, resulting in PAH
Is there a clinical benefit in IPF for existing drug trials?
NO!
Goodpasture syndrome
Pathogenesis and Treatment
- type II HSR agaisnt alpha-3 chains of type IV collagen in basement membranes of lungs and kidneys
- plasmapheresis for treatment
What is Wegner’s Granulomatosis?
ANCA-positive autoimmune vasculitis (small-medium vessels), primarily of the upper respiratory tract, lungs and kidney.
What is the treatment for Wegner’s Granulomatosis?
Variety of anti-inflammatory agents
- Rituximab
- Off label usage of
- Azathioprine
- Cyclophosphamide
- Corticosteroids
Rituximab MOA
immunosuppressing monoclonal antibody that binds the CD20 cell surface antigen on B-cell precursors and mature B-lymphocytes. Cell populations are depleted, and depletion is long-lasting (6-9 months follwing a single drug course; 3 doses).