cystic fibrosis
Cystic fibrosis in paediatrics Important advances in the treatment and management of cystic fibrosis (CF) have resulted in huge improvements in the health of people with CF. Individuals born with CF in the 21st century are now expected to live into their mid-50s, even in the absence of developments in the treatment of the underlying genetic defect (1). Jacqui Lowden Paediatric Dietitian - Team Leader Critical Care, Therapy & Dietetics, RMCH
One of the advances in CF management that has demonstrated the prevention of severe malnutrition and improvement in long-term growth, is new-born screening (2) which was introduced nationally in 2007. Maximising nutritional status has, however, long been considered a crucial element, being inextricably linked with lung function. The level of malnutrition has been demonstrated to predict survival (3). As the disease progresses, increased nutritional support is normally required. Dietary fortification, oral nutritional supplements and enteral tube feeding are all used. Infants with CF
Presently team leader for Critical Care and Burns, Jacqueline previously specialised in gastroenterology and cystic fibrosis. Although her career to date has focused on the acute sector, Jacqueline has a great interest in paediatric public health.
Even with the benefits of infant screening, deficits in weight, length z score, total body fat and lean body mass have all been demonstrated in screened infants with CF at diagnosis (2, 4). A higher than normal intake of protein and energy has also been shown to be required in these infants in order to achieve normal rates of weight gain and growth (5). It is vital that infants with CF thrive, as achieving optimal nutritional intake and catch-up in weight gain within the first two years of diagnosis in children with CF has been shown to be the single strongest predictor of lung function improvement at six years of age, which is correlated to reduced morbidity and mortality (6). Most infants with CF thrive on breast milk or normal infant formulae until the commencement of complementary feeding. If the infant is unable to achieve the required amount and/or weight gain is
insufficient, a nutrient dense infant formula can be used. There is no evidence for the use of a protein hydrolysate formula in screened infants with CF (7). For infants with CF who have undergone bowel surgery due to meconium ileus, the choice of feed will depend on: 1. the extent of the small intestinal resection; 2. the site of the ileostomy; 3. parental choice to breastfeed. First choice is expressed breast milk whilst establishing breastfeeding, second a protein hydrolysate with a combination of MCT/LCT and thirdly, a standard infant formula. Another factor to take into account is sodium depletion, as this can inhibit growth (9). All infants with CF are at risk of sodium depletion. Particularly at risk are those with ileostomies as the sodium content of the output can be high. European Cystic Fibrosis Society guidelines suggest that ‘sodium chloride supplementation (2.0mmol kg/ day) should be considered for all CF infants, and increased during periods of hot weather and with other causes of high salt loss (for example, diarrhoea, fever and ileostomy)’ (8). Older children
Definitions of nutritional failure The intervention required will be dependent on clear definitions of what is classed as nutritional failure. Presently, there are three sets of national reference standards (Table 1). For children
NHDmag.com December 2014 / January 2015 - Issue 100
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