Cystic fibrosis Flashcards
What causes cystic fibrosis?
Autosomal recessive genetic condition
Defective CTFR membrane protein (cyclic AMP-dependent chloride channel)
CTFR gene is located on chromosome 7
F508 most common defect
Different factors are important in determining the severity of lung disease- pathogens, passive smoking, social deprivation
What is the pathophysiology for CF?
Airways- reduction in airway surface mucus layer, impaired ciliary function and retention of mucopurulent secretions
Chronic endobronchial infections ensure with specific organisms-Pseudomonas aeruginosa
Dysregulation of inflammation and defence against infection
Intestine- thick viscid meconium is produced (meconium ileus)
Pancreatic ducts blocked by thick secretions- leads to pancreatic enzyme deficiency and malabsorption
Abnormal sweat glands- excessive sodium and chloride in sweat
What are the symptoms of CF in infancy?
Meconium ileus in newborn period- inspissated meconium causes intestinal obstruction with vomiting, abdominal distension and failure to pass meconium for the 1st few days of life
Prolonged neonatal jaundice
Failure to thrive
Recurrent chest infections: S. aureus, H. influenzae with subsequent infections of Pseudomonas aeruginosa or Burkholderia species
Malabsorption steatorrhoea
Hypoproteinaemia and oedema
What are the symptoms of CF in a young child?
Bronchiectasis Rectal prolapse Nasal polyp Sinusitis Anorexia
What are the symptoms of CF in older children and adolescents?
Allergic bronchopulmonary aspergillosis (ABPA) Diabetes mellitus Cirrhosis and portal hypertension Distal intestinal obstruction- DIOS, meconium ileus equivalent Pneumothorax or recurrent haemoptysis Sterility in males Arthropathy Psychological problems
What do chronic chest infections cause?
viscid mucus in the smaller airways leading to damage of the bronchial wall, bronchiectasis and abscess formation- may have persistent, loose cough and productive purulent sputum
What is seen on examination with CF?
Hyperinflation of chest, coarse inspiratory crepitations and/or expiratory wheeze
Finger clubbing
How is meconium ileus treated?
Gatrografin enemas
What are the investigations for CF?
Sweat test- increased chloride levels (>60mmol/L)
CXR- hyperinflation, increased AP diameter, bronchial dilation, cysts, linear shadow and infiltrates
Lung function- obstructive pattern and decreased FVC and increased lung volume
Who make up the multidisciplinary team for CF?
Paediatric pulmonologist Physiotherapist Dietician Nurse liaison or practitioner in CF Primary care team Teacher Psychologist
What is an indicator of clinical severity in CF?
FEV1, declines with disease progression
What is the pulmonary care for CF?
Physiotherapy twice a day Taught how to: Chest percussion Postural drainage Self-percussion Deep breathing exercises Use of flutter or acapello device
What is the antibiotic therapy for CF?
When well- oral Abx (flucloxacillin) against Staphylococcus aureus & Haemophilus influenzae
Acute exacerbations- 14 day course of IV Abx through an indwelling long-line that should last several weeks
Pseudomonas aeruginosa- nebuliser for those chronically infected
Other therapies- annual flu vaccine, bronchodilators, mucolytics (before physio) and oral azithromycin
What is given for distal intestinal obstruction?
Lactulose- 1mL/kg/day
Oral acetylcysteine solution- prophylaxis 15mL of 10%/day in <7yrs or 30mL in >7yrs- treatment doses and x2-3 larger
Gastrografin- single oral dose treatment with fluid intake encouraged after
What is given for pancreatic insufficiency?
Treated with oral enteric-coated pancreatic supplements (Creon) taken will all meals and snacks- Ranitidine or omeprazole may be useful if response is unsatisfactory
