Smith-Magenis Syndrome: PEG feeding case study

PeG feediNG A Child with Smith-mAGeNiS SyNdrome:

Emma Coates senior Paediatric dietitian wrexham maelor hospital, Betsi Cadwaladr university health Board, north wales

a case study

Since the 1980s, percutaneous endoscopic gastrostomy (PEG) tubes have become an increasingly common way to provide nutrition support in a huge variety of paediatric patient groups (1) (see table 1). The indications for PEG feeding are as wide ranging as the patient groups they are used in (see Table 1) and PEG fed patients are often a significant part of a general paediatric dietitian’s caseload. Many require ongoing support and monitoring throughout the duration of their episode of PEG feeding. This can vary greatly, with many patients requiring dietetic support for many years, perhaps for life. However, there are many patients who can be successfully weaned from PEG feeding to oral diet, which is discussed in this case study.

Jack was transferred to our dietetic department when his family moved to our area at the age of four. He was solely PEG fed at the time of referral. At his previous hospital he had been diagnosed with Smith-Magenis syndrome (SMS), a rare genetic condition caused by a microdeletion or abnormality of chromosome 17. Patients with SMS may develop distinctive facial features and dental abnormalities are also common. Mild to moderate cognitive disability, delayed speech and language skills, sleep disturbances and behavioural problems (2) are also common. Further details of SMS features can be found in Table 2, many of which have been observed in Jack’s development and behaviour.

Feeding problems in infancy are common for SMS patients and Jack had been difficult to feed from birth. He did not latch on particularly well when his Mum attempted to breastfeed him. When bottle feeding was introduced, Jack was slow to feed and he would often cough and splutter during his feeds. He would easily vomit after each feed and he would cry inconsolably after feeds. Mum described reflux/GORD type symptoms during or post feeds. His swallowing ability was assessed during a videofluroscopy. He had poor oro-motor control due to low muscle tone and some aspiration was observed with unthickened formula.

emma has been working as a Paediatric dietitian for five years and her caseload includes hetf, disability, coeliac disease, cystic fibrosis, PKU and childhood obesity. She has been a local Coeliac UK group organiser for 18 months. table 1: Examples of PEg fed patient groups and indications for PEg feeding

Patient groups

neurodisability

Cardiology

Renal

Progressive neuromuscular diseases, e.g. duchene’s muscular dystrophy

Cystic fibrosis short bowel syndrome/malabsorption, e.g.

Crohn’s disease or surgery oncology

Craniofacial abnormalities allergy

Behavioural feeding problems

indications for Peg feeding

unable to achieve and maintain nutritional requirements via oral intake alone leading to faltering growth, this may be due to:

Physical and cognitive developmental delay dysphagia or oro-motor difficulties increased requirements oral feeding aversion Reflux/goRd malabsorption upper gi obstruction/tumours

At the age of three, Jack developed severe vomiting and diarrhoea episodes within the hour following his daytime 150ml bolus feeds of a 1.5kcal/ml tube feed.

However, he was much improved when his formula was thickened with Carobel (Cow and Gate) to stage 1 thickness. This also improved his reflux symptoms. He was referred for placement of a PEG at the age of nine months as his weight had fallen through two centiles, from the 50th to the 9th centile over eight weeks and he had continued to falter despite being prescribed a high calorie formula, 0.9kcal/ml - SMA High Energy, which was the only high calorie formula available at that time. Jack’s mum had attempted to start weaning at six months of age. However, he displayed little interest in solid food and he would only accept lip smears of fruit puree. If mum attempted to place a spoon in his mouth, he would retch and gag, often leading to him vomiting up an entire milk feed. At the age of nine months, Jack’s physical development was delayed and he was only just starting to sit independently. He was also prescribed randitine and domperidone as his reflux symptoms had worsened.

Once the PEG was insitu at almost 11 months of age, Jack’s weight was between the 2nd and 9th centile, his length was following the 2nd centile. He was given 5x150ml gravity bolus feeds of SMA High Energy per day (approximately 86kcal/kg/day). Despite this low calorie intake he gained weight. Mum reported that Jack was not particularly active at this age and this may have accounted for his lowered energy requirements at that time. His weight improved over the next four weeks and he reached the 9th centile. He continued to refuse any oral intake of solids and his oral intake of formula was minimal, despite mum providing the opportunity to take them at each meal and feed during the daytime. At the age of 15 months, Jack’s feed was swapped to a 1.0kcal/ml tube feed. He continued to tolerate 150ml boluses, but a night-time pump feed had been introduced as his requirements increased. Mum was unable to give the 6x150ml bolus feeds that he needed, due to the development of some challenging behaviours, for example, temper tantrums including kicking and slapping her when she was giving him a bolus feed. To minimise the amount of time Jack was being fed, either via a bolus or his pump, he was swapped on to 1.5kcal/ml feed at the age of 18 months. He also had his PEG tube replaced with a low profile feeding tube - a MicKey button. Jack was frequently awake at night and he would pull the tubing on the feed pump. His parents were sleeping in his room to ensure that they could reset the pump if he pulled the tubing out. He frequently had disrupted pump feeds throughout the night, but parents were unable to feed him anymore than they were doing in the daytime due to his behaviour. Despite this, his weight followed the 9th centile and his length continued along the 2nd centile. He continued to take minimal oral diet and fluids.

At the age of three, Jack developed severe vomiting and diarrhoea episodes within the hour following his daytime 150ml bolus feeds of a 1.5kcal/ml tube feed. However, he seemed to tolerate his night-time feeds, despite the ongoing problems with his behaviour. His reflux seemed worse, despite being prescribed ranitidine and domperidone. He was also later prescribed omeprazole. This eased his reflux symptoms initially, but the episodes of vomiting and diarrhoea persisted. Mum also noted during these episodes that Jack had started to perspire, he seemed to lose concentration and his muscle tone seemed to dip. He would

At the age of six and a half, Jack’s dietary intake had expanded; he started to include some protein sources such as ham and cheese. He also started to tolerate

a larger carbohydrate load and he was managing 20-30g per mealtime.

become very drowsy or fall asleep. He was referred to a specialist paediatric gastroenterologist as dumping syndrome was suspected by his paediatrician. For 18 months, Jack was investigated for dumping syndrome via various scans, scopes, blood glucose monitoring and a gastric emptying study. The various test results were not entirely conclusive, but he was given the diagnosis of dumping syndrome. In order to manage his dumping syndrome symptoms, he was placed on a 20-hour pump feed, which ran throughout the day and night and, by doing so, Jack was able to meet his nutrition and hydration requirements. He was able to wear his feed and pump in the daytime by using a specially adapted backpack. This was challenging for his parents and school staff to manage, as Jack would frequently pull the backpack off, or he would need to engage in activities where the backpack was not practical, for example, hydrotherapy.

Jack continued to be solely and continuously PEG fed until he was almost five years old. Jack then started to eat small amounts of soft plain egg noodles, penne pasta with carbonara sauce and garlic bread. Despite his inexperienced feeding skills, he was able to suck and mulch these foods then swallow them without retching or gagging. He refused to drink any fluids, but he would take custard thick foods made with liquids such as milk or water. A repeat videofluroscopy highlighted that he was safe to swallow these foods and unthickened liquids. All foods were introduced slowly, as it was noted on more than one occasion by mum that if he had more than a handful (his size) of the foods he had started to take, he would start to experience the dumping syndrome symptoms again. Mum kept a food/symptom diary and the pattern was consistent each time the amount of food taken was increased above the handful sized amount (estimated carbohydrate load of 10-20g). Mum attempted to introduce foods with a lower carbohydrate value; however, Jack refused many of the new foods offered.

At the age of six and a half, Jack’s dietary intake had expanded; he started to include some protein sources such as ham and cheese. He also started to tolerate a larger carbohydrate load and he was managing 20-30g per mealtime. His intake of fluids also improved and he was drinking approximately 200ml whole cows’ milk at each mealtime (three meals per day). Mum had attempted to give him a variety of 1.5kcal paediatric supplement drinks, but Jack refused to take them.

In light of Jack’s much improved oral intake, we were gradually able to reduce his pump feeds. We monitored his weight each month and he had gained a little more weight than required and he was tracking along the 50th centile. This gave mum the confidence to try more foods with Jack as she understood that he had some reserve weight and it wasn’t as much of a priority to give the highest calorie foods at every meal or snack time. Jack gradually accepted some fruits and vegetables as well as further protein rich foods. His dumping syndrome episodes became far less frequent despite his increasing intake of carbohydrate sources.

At the age of almost nine, Jack was almost PEG-feed free. He was still having a 250ml night-time feed, which was still causing a lot of challenging behaviour. He had started to pull

. . . Jack has developed a number of problems with his PEG site. He has had numerous site

infections . . .

his entire gastrostomy device (MicKey button) out on a frequent basis, for example, up to 10 to 12 times per day. This would occur during the daytime, despite him not needing daytime feeds any longer. Parents and school staff were able to manage this by receiving training to reinsert his MicKey button. Despite this, Jack continued to frequently pull at his MicKey button, which might have been a sensation he enjoyed rather than it being a painful experience. As a consequence of this behaviour, Jack has developed a number of problems with his PEG site. He has had numerous site infections, which have required antibiotic treatment. Due to his frequent pulling on the device, his site has stretched and can leak gastric contents on the abdominal skin, causing sores, which are an infection risk.

As Jack’s weight and height were satisfactory his night-time feed was discontinued after his 9th birthday. He is now 10 years old and he has continued to eat and drink well on most days. He can be a ‘picky’ eater some days, but his weight and height growth have remained satisfactory. Jack continues to pull at his MicKey button at times, but this behaviour has subsided considerably. He continues to require the tube for medications at present, but it is a future goal for Jack to progress to oral medications. Jack has been an extremely challenging PEGfed patient to manage due to his physical and behavioural problems. He has required considerable dietetic support, which has taken place over many years at home, at school and within the hospital setting. His case has required wide range of dietetic skills and knowledge, which have eventually facilitated his progression from tube to oral feeding.

table 2: Common features of smith-magenis syndrome (2)

in infancy

Poor oral feeding low muscle tone/physical developmental delay Faltering growth lethargy/extended sleep times Poor development of feeding skills Reflux/goRd

in childhood

ongoing feeding problems sleep disturbances - waking during the night, tiredness during the daytime delayed speech and cognitive development toileting problems Behavioural problems: ‘jekyll and hyde’ type moods, regular temper tantrums, impulsive behaviour, anxiety, easily distracted, aggressive behaviour self-injurious behaviours including self-hitting, self-biting and skin picking, ‘self-hugging’, hand licking, hand flapping, mouthing objects, insertion of hand in mouth, teeth grinding, body rocking and spinning or twirling objects Physical features - short stature, abnormal curvature of the spine (scoliosis) sensory abnormalities, e.g. reduced sensitivity to pain and temperature hoarse voice, possible ear abnormalities that may lead to hearing loss and also possible vision difficulties some sms patients may experience cardiac and renal defects

references: 1 el-Matary w. Percutaneous endoscopic gastrostomy in children. can J Gastroenterol. 2008 Dec; 22(12):993-8 2 what is sMs? (2014). http://smile.smith-magenis.org/ <accessed 09/11/14>