Respiratory Medicine Flashcards
(73 cards)
Histoplasmosis
-Most common systemic mycosis in North America.
-Typical X-ray changes include patchy pulmonary infiltrates with mediastinal widening.
- Culture of Histoplasma capsulatum from blood, urine, bone marrow, and sputum.
-Rx with amphotericin B is not required till the patient shows signs of respiratory insufficiency.
Allergic Bronchopulmonary Aspergillosis
- Infection caused by inhalation of spores from the Aspergillus fumigatus.
- The allergens induce type 1 and type 3 hypersensitivity reactions.
- Elevated serum IgE and aspergillus-specific IgE
- Elevated Aspergillus-specific IgG.
- Eosinophilia.
- Rx is Systemic corticosteroids.
Bronchiectasis
- Chronic progressive disease leads to inflamed, dilated, obstructed airways.
-Recurrent chest infections. - Purulent sputum
- Idiopathic ( 40 %)
- CT shows the signet ring sign ( dilated bronchus).
PFTs showed normal, obstructive, restrictive, or mixed patterns. - Two clinical scoring systems
( BSI and FACED )
LTOT indications
-PaO2 <7.3 kPa
- PaO2 7.3-8.0 kPa with additional risk factor ( secondary polycythemia, nocturnal hypoxemia, peripheral edema, pulmonary HTN ).
MRC Dyspnea scale
Grade 1- Mild
Grade 2,3 - Moderate
Grade 4,5 - Severe
COPD ( severity of airflow obstruction)
FEV1 > 80% Mild
FEV1 50-79 % Moderate
FEV1 30-49 % Severe
FEV1 < 30% Very Severe
Management of COPD
-SABA or SAMA
Then
LABA + LAMA If Asthma LABA +ICS
Then
LABA + LAMA + ICS
Invasive Treatments for COPD
1- LUNG VOLUME REDUCTION SURGERY
-FEV1 <50%
-Not smoking
-6 min walk test > 140 m
- Lung hyperinflation
2- BULLECTOMY
Bullae >1/3 of hemithorax
3- LUNG TRANSPLANTATION
-FEV1 <50%
-Not smoking
- Completed pulmonary rehab
- No contraindications
Lung Cancer
1- Small cell ( 20%), most aggressive
2- Non-small cell ( 75-80%)
- Squamous cell ( most common)
- Adenocarcinoma
- Large cell
- Undifferentiated
Lung cancer Investigations
- CXR
-CT - Peripheral lesions <10mm nodules, then PET CT scan
-Peripheral lesions >10mm nodules, then Biopsy
-For central lesions, flexible bronchoscopy
Emphysema
A reduced transfer factor and CXR evidence of hyperexpanded lung fields points towards a predominantly emphysematous picture.
Heerfordt’s syndrome
Heerfordt’s syndrome is an acute presentation of sarcoidosis, which presents with fever, uveitis, swelling of the parotid and other salivary and lacrimal glands.
Lofgren’s syndrome
Lofgren’s syndrome is a subtype of sarcoidosis which presents with hilar lymphadenopathy, erythema nodosum, arthralgia and fever.
Lung Compliance
Lung compliance is defined as change in lung volume per unit change in airway pressure
Causes of increased compliance
1-age
2- emphysema - this is due to loss alveolar walls and associated elastic tissue
Causes of decreased compliance
1-pulmonary oedema
2-pulmonary fibrosis
3-pneumonectomy
4- kyphosis
Mycobacterium Avium
Mycobacterium avium is an opportunistic mycobacterium, which is a ubiquitous environmental organism acquired by person-to-person spread. In immunocompetent patients, such as this gentleman, M.avium can cause pulmonary infection in one of two patterns:
- disease resembling tuberculosis, often in elderly smokers with chronic lung disease, or
- nodular infiltrates and a bronchiectasis-like pattern in those without chronic lung disease, with a productive cough but no systemic symptoms
Investigation in the immunocompetent is initially with sputum AFB staining, which is positive in most cases. Sputum culture should be done, but it does not differentiate between infection and colonisation. More than one positive culture is required for diagnosis for this reason. - Treatment is with a combination of two or three antibiotics for at least 12 months. The exact combination depends on local guidelines.
Complication of cystic Fibrosis
1- Pancreatitis is a known complication of cystic fibrosis and should be suspected in patients presenting with abdominal pain, nausea, vomiting, and elevated amylase levels, especially in those with residual pancreatic function.
- Cystic fibrosis-related diabetes (CFRD).
-
Nodules less than 10mm
A PET-CT scan is recommended for pulmonary nodules larger than 8 mm to evaluate malignancy risk, especially in individuals with risk factors such as a smoking history.
Histiocytosis X
Pentalaminar X bodies (Birbeck granules) found on BAL are considered diagnostic of pulmonary histiocytosis X .
Eosinophilic Granulomatosis with Polyangiitis (EGPA
Eosinophilic Granulomatosis with Polyangiitis (EGPA) is a rare form of small-vessel vasculitis, characterised by asthma, allergic rhinitis and prominent peripheral blood eosinophilia. Rarely, it can cause either an anterior or a posterior ischaemic optic neuropathy, which presents with visual loss.
The most commonly involved organ is the lung, followed by the skin. EGPA, however, can affect any organ system, including the cardiovascular, gastrointestinal, renal, and central nervous systems. The unifying feature of patients presenting with EGPA is asthma. Vasculitis involving the peripheral nervous system is also a characteristic feature, and mononeuritis multiplex occurs in 75% of patients, which accounts for the foot drop in this case.
Vasculitis of extrapulmonary organs is largely responsible for the morbidity and mortality associated with EGPA. 40-60% are associated with positive ANCA, usually pANCA/MPO.
Intravenous glucocorticoid is used for initial therapy of acute multi-organ disease, followed by oral glucocorticoid therapy, often with azathioprine as a steroid-sparing agent
Asthma
Low magnesium levels in bronchial smooth muscle favour bronchoconstriction.
Initial approach SOS
-Salbutamol, Oxygen, Steroids
Then
Mg 2gm over 30 min
Causes of a raised TLCO
- Asthma
- pulmonary haemorrhage (e.g. - granulomatosis with polyangiitis, Goodpasture’s)
- left-to-right cardiac shunts
- polycythaemia
- hyperkinetic states
- male gender,
- exercise
Causes of a lower TLCO
- pulmonary fibrosis
- pneumonia
- pulmonary emboli
- pulmonary oedema
- emphysema
- anaemia
- low cardiac output
Causes of increase KCO
KCO also tends to increase with AGE. Some conditions may cause an increased KCO with a normal or reduced TLCO
- pneumonectomy/lobectomy
- scoliosis/kyphosis
- neuromuscular weakness
- ankylosis of costovertebral joints e.g. ankylosing spondylitis
Asthma Ix in Adults
Investigating suspected asthma in adults
First-line investigations NICE
measure the eosinophil count OR fractional nitric oxide (FeNO)
diagnose asthma, without further investigations, if:
eosinophil is above the reference range
FeNO is ≥ 50 ppb
If asthma is not confirmed by the eosinophil count or FeNO
measure bronchodilator reversibility (BDR) with spirometry
diagnose asthma if:
the FEV1 increase is ≥ 12% and 200 ml or more from the pre-bronchodilator measurement, or
the FEV1 increase is ≥ 10% of the predicted normal FEV1
if spirometry is not available or it is delayed, measure peak expiratory flow (PEF) twice daily for 2 weeks
diagnose asthma if:
PEF variability (expressed as amplitude percentage mean) is ≥ 20%
If asthma is not confirmed by eosinophil count, FeNO, BDR or PEF variability but still suspected on clinical grounds:
refer for consideration of a bronchial challenge test
diagnose asthma if bronchial hyper-responsiveness is present
