Section 10 - Cystic Fibrosis Clinical Care Pathway

Section Three:
Nutritional Management
3.1 Nutritional Management
Importance of nutritional status
Malnutrition is not an inevitable consequence of CF and can be prevented or
corrected. Poor nutritional status can lead to:
• Stunted growth, delayed onset of puberty/sexual development.
• Weight loss due to loss of adipose tissue and muscle wasting (including
the respiratory muscles). This can eventually impair the ability to cough
leading to an increase in respiratory infections and decline in lung
function. Appetite may be further affected by the large amounts of
mucus swallowed due to inadequate coughing.
• Poor body image, leading to depression and school absenteeism.
• Decreased immune function.
• Specific signs of certain nutrient deficiencies (e.g. of fat soluble vitamins
or essential fatty acids).
Patients with CF may have altered nutritional requirements as a consequence
of three interrelated factors: malabsorption, increased energy expenditure and
poor intake.
a) Malabsorption
Increased stool losses of fat, fat soluble vitamins and protein often occur in
CF due to one or more of the following:
• Pancreatic enzyme deficiency (affecting >85% of patients).
• Low intestinal pH, secondary to lack of pancreatic bicarbonate and over
production of gastric acid. Some patients with persistent malabsorption
may benefit from H2 receptor antagonists such as ranitidine taken 30
minutes before meals or proton pump inhibitors such as omeprazole
once daily.
• Excessive, viscous intestinal mucus presenting a physical barrier to
nutrient absorption.
• Bile salt abnormalities (both quantitative and qualitative) due to
decreased ileal bile reabsorption and increased stool losses.
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