Suppurative lung diseases

Question 2

Cystic fibrosis basic info, C/P?

Answer 2

• One of the common inherited AR disorders (linked to chromosome 7)
• Due to a defect in CFTR (cystic fibrosis transmembrane regulator) protein, which is a chloride channel regulator leads to chloride (with passive movement of sodium and water) is poorly secreted by mucosa, causing secretions that are dehydrated and thick.
• Two main problems:
  o Impaired ciliary motility by thick secretions leads to Recurrent chest infections causing chronic lung damage (bronchiectasis)
  o Pancreatic duct obstructions by thick secretions leads to Malabsorption (due to reduced pancreatic enzymes) causing failure to thrive.

Clinical features:
Symptoms:
o At birth: meconium ileus and prolonged neonatal
o jaundice.
o Failure to thrive and loose fatty stool
o Recurrent chest infections
o Delayed puberty
Signs:
o Chronic lung damage with variable presentations
o Failure to thrive and delayed puberty
o Clubbing of the fingers and toes
o Hepatosplenomegaly
o Sinus: Sinusitis and polyps
o Lungs: Airway obst, bronchiectasis. pneumothorax and hemoptysis
o Liver: Obstructive biliary tract disease
o Pancreas: Enzyme insufficiency, insulin-dependant DM
o Intestine: Meconium ileus, DIOS, rectal prolapse
o Reproductive: Male infertility and congenital absence of vas deferens
o Skin: sweet chloride >60 mmol/liter

Question 3

Cystic fibrosis investigations and Treatment?

Answer 3

Investigations:
- Chest – X-ray:
o Bronchial wall thickening
o Hyperinflation with flattened diaphragm
o Picture of bronchiectasis: ring, line shadows, and increased interstitial markings.
- Sweat chloride test “Gold standard” test for diagnosis
o Sweat is collected in a sweat chamber and the chloride content of the sweat is analysed: in cystic fibrosis it is high (> 60 mmol/L)
o Two tests are needed to confirm the diagnosis
- Gene analysis: > 1000 different gene mutations have been found. Loss of phenylalanine at position 508 (∆ 508) is the most common.
- Stool: children with pancreatic insufficiency have low elastase, absent chymotrypsin and high fat content
- Hypokalemia alkalosis due to sodium and potassium loss in the sweat
- Blood: elevated immunoreactive trypsinogen suggests pancreatic dysfunction. (This is the principle of neonatal screening test )

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Treatment:
- Lung disease
o Physiotherapy often twice daily, individualized to patient
o Antibiotics: Long term or pulsed orally as prophylaxis. May be nebulized.
o Intercurrent infections treated as necessary (oral or IV for 2 weeks)
o Bronchodilators
o Oxygen at home as disease progresses
- Gastrointestinal disease
o Oral pancreatic enzyme supplements
o Optimum nutrition (high calorie, high protein diet, vitamins, bile acids, salt is needed in hot climates and sometimes for babies)
- Other treatments
o Mucolytics, e.g., DNase or hypertonic saline
o Liver transplant
o Heart-lung transplantation in end-stage disease
o Treatment for complications, e.g. insulin for cystic fibrosis related diabetes (CFRD)
o Gene therapy is still being researched.

Prognosis:
o Markedly affected life expectancy usually < 32 years
o infertility is nearly universal in male CF patients due to absent vas deferens, although spermatogenesis can be normal.

Question 4

Bronchiectasis definition, causes and c/p?

Answer 4

Definition
Bronchiectasis means abnormal and permanently dilatation of the bronchi due to chronic airway inflammation and infection.

Causes of bronchiectasis
1- Congenital
* Cystic fibrosis
* Primary ciliary dyskinesia
* Kartagener’s syndrome (sinusitis ,immotile cilia,bronchiectasis and transposition of the viscera)
* antitrypsin deficiency:
* Primary hypogammaglobulinemia
2- Acquired
* Pulmonary infections
* Bacterial (staphylococci, klebsiella, TB, anaerobes)
* Viral (adenovirus,influenza,)
* Pneumonia (complicating whooping cough or measles)
* Inhaled foreign body
* Suppurative pneumonia
* Pulmonary TB
* Allergic bronchopulmonary aspergillosis complicating asthma
3- others
* Bronchial tumors
* Rheumatoid arthritis and Sjogren’s syndrome

Clinical features:
a) Symptoms:
-Cough + expectoration of mucopurulent sputum related to posture wore in the morning ).
- Hemoptysis: may be massive.
- Recurrent infection especially with wet bronchiectasis: large volume + purulent sputum.
- dyspnoea: late symptom; in wide spread disease with extensive fibrosis + destruction.
- Wheeze: not common
- Other coexisting symptoms: upper respiratory infection + sinusitis - Cystic fibrosis.
B) Signs:
- Early crackles 3 (Inspiratory & expiratory - Coarse - Not affected by coughing).
- Clubbing: commonly with cystic fibrosis.
- Halitosis
- Signs of collapse and fibrosis: in advanced cases with cyanosis.
- May signs of complications (pulmonary hypertension, right heart failure)

Question 5

Bronchiectasis investigations, management and complications?

Answer 5

Investigations
- Sputum: culture and sensitivity
- Radiology: x-ray:
a) May → No abnormalities.
b) Evidence of dilated bronchi : ring shadows (honeycomb lung) - dilated bronchi - if large (0.5 3 2 cm) diffuse : cystic lung.
- CT CHEST is much more sensitive and shows thickened dilated airways.
- Bronchoscopy
- Assessment of ciliary function.
- PFT (pulmonary function test )
o Localized bronchiectasis: normal PFT
o Diffuse bil. Bronchiectasis: obstructive pattern
o Associated with atelectasis, parenchymal & pleural scarring restrictive pattern
-Investigations of the cause: Serum immunoglobulin

Management and prognosis
1- postural drainage at least 3 times daily
2-Antimicrobial chemotherapy.
Initial antibiotics include amoxicillin ,azithromycin,quinolones,cephalosporine or aminoglycoside, duration for 10-14 days. In case of failure of response to treatment and frequent exacerbation, sputum culture and sensitivity should be done.
3-bronchodilators in airway limitation
4- surgery for localized cases Mucus clearance ; via
- Maintenance of hydration with oral and I.V. fluids
- Humidification of inhaled air or oxygen.
- N acetylcysteine.

Complications:
1) infective exacerbations.
2) Haemoptysis.
3) Chronic paranasal sinusitis.
4) Cor pulmonale.
5) Brain abscess through vertebral system of veins or 3 paranasal sinuses infection.
6) Amyloidosis.
7) Disseminated aspergillosis.
8) pneumonia, empyema, atelectasis, bronchopleural fistula, pneumothorax.

Question 6

Lung abscess definition, causes and c/p

Answer 6

Definition:
it is a localized area of tissue necrosis, suppuration and cavitation due to pyogenic infection, when lung abscess cavities are small < 2 cm in diameter, they are sometimes referred to as necrotizing pneumonia.

Causes:
- Aspiration :especially in altered consciousness,vomitus in comatosed patient
- Tuberculosis.
- Pneumonia caused by certain species, particularly Staphylococcus aureus or Klebsiella pneumonia.
- Infected pulmonary infarct or hematoma.
- Septic emboli usually containing staphylococci: these can cause multiple lung abscesses. The presence of multiple lung abscesses in an injecting drug user should prompt investigation for infective endocarditis of the tricuspid valves. Infarcted areas of lung (due to pulmonary emboli) occasionally cavitate and become infected.
- Spread from nearby sites: chest wall, mediastinum, subdiaphragmatic sources (Sub phrenic abscess, an amoebic liver abscess: amoebic lung abscesses occasionally develop in the right lower lobe following transdiaphragmatic spread).
- Bronchial obstruction by an endoluminal cancer
- Foreign body inhalation.
- Chronic or subacute lung abscesses may follow inadequate treatment of pneumonia.

Clinical features:
Symptoms:
- Fever, cough, purulent sputum related to posture and begins with sudden gush of large amount, dyspnea, chest pain (pleuritic or deep seated discomfort) and may haemoptysis.
N.B. If sputum has putrid small (bad odour): anaerobic infection is the likely cause.
- In staphylococcal infection : symptoms are acute and fulminating.
Signs:
- general : finger clubbing within some weeks.
Local : decrease movement on affected side, may lead to impaired percussion note and diminished breath sounds ± added crepitations and pleural rub.

Question 7

Lung abscess investigations, DD, complications and ttt?

Answer 7

Investigations:
- Chest radiography: cavity lesion with air-fluid level
- CT CHEST
Microbiology:
-CBC polymorph leukocytosis
-Sputum examination
-Sputum culture and sessetivity
-Blood cultures in metastatic abscesses.
Bronchoscopy.

• Differential diagnosis:
• Other SLDs.
• Cavitated bronchial carcinoma (Thick irregular wall, abnormal site).
• TB & fungal infection.
• Encysted pneumothorax
• Infected bulla containing a fluid level or infected hydatid cyst.
• Hiatus hernia

Complications:
1-Hemoptysis
2- Extension of infection to;
* pleura
* other parts of the lung
* distant organs
3.Pyopneumothorax
4.Chronic abscess
* Cachexia
* Anemia

Treatment.
1-Postural drainage.
2- Proper antibiotic chemotherapy. According to culture and sensitivity testing if possible, but empiric antibiotic therapy could be started using strong antibiotic with good tissue penetration, e.g: new generations of quinolones as moxifloxacin, gatifloxacin, levofloxacin (once daily), ciprofloxacin, ofloxacin (twice daily).
3- Bronchoscopic or radiographically guided catheter drainage of any fluid or necrotic debris.
4-Surgical resection of affected lung segments.
N.B: In patients with coexisting empyema and lung abscess, it is better to drain empyema firstly then consider further procedures.