1. + DIOS: A Dietitian’s Perspective Michelle Stroebe, MS RD Adult Cystic Fibrosis Center Stanford Healthcare

2. + Overview What is DIOS? Why is DIOS only in CF? Signs/Symptoms of DIOS Common Triggers Treatment Prevention Impact on Nutrition When to Call Your Medical Team

3. + What is DIOS? DIOS = Distal Intestinal Obstructive Syndrome Specific to Cystic Fibrosis (CF), mostly pancreatic insufficient Lifetime prevalence of DIOS: ~16% of CF adults, ~10-20% post- transplant CF adults/children Type of constipation caused by mucus buildup in intestines May cause complete or incomplete blockage of stool at junction where small intestine ends and large intestine (colon) begins Onset of symptoms may be sudden and may cause extreme discomfort Recurrence is common

4. + What is Constipation? Stool impaction in colon Occurs in both pancreatic insufficient and sufficient patients Usually occurs gradually over time Associated with gas, bloating, mild abdominal pain Hard, pebbly stools that are hard to pass

5. + Why is DIOS only in CF? Incidence of meconium ileus at birth may increase risk for DIOS (risk of occurrence 18-44%) Pancreatic insufficiency requiring enzymes Missing, skipping, under dosing of enzymes Imperfect digestion even with enzyme use  Leads to sticky intestinal mucous (malabsorption) CFTR gene mutation leading to: Impaired intestinal motility Impaired intestinal secretion  dry, sticky gut Malabsorption + dry, sticky gut  harder to pass stools

6. + Signs & Symptoms of DIOS Decreased number or frequency of stools i.e. normal stooling = 2-3 medium sized stools/day Reduced to 1-2 small stool(s)/day OR no stool for 1-2 days Cramping/abdominal pain, usually starting in right lower side of abdomen Pain continues to worsen and may cause extreme pain Watery, loose stools that do not relieve abdominal pain Nausea/vomiting Inability to tolerate food, decreased appetite, abdominal fullness Bloating/abdominal distention

7. + Common Triggers Dehydration Poor hydration at baseline OR Inadequate replacement of fluid losses Discontinuation of bowel regimen Malabsorption Inadequate enzyme use or skipped enzymes Surgery Immobilization, reduced activity

8. + Treatment Easily misdiagnosed by those unfamiliar with the condition… If diagnosed early enough (incomplete DIOS): Oral laxatives (i.e., Miralax, GoLytely) usually at home Titrated by your medical team to cleanse intestines of impacted stool If diagnosed late and suspected complete DIOS: “Clean out” likely requiring hospitalization Abdominal x-ray Enemas, laxatives IV hydration NG tube for decompression to help with abdominal distention/nausea &/or to administer laxatives into stomach

9. + Prevention Strict adherence to enzyme regimen &/or adequate enzyme coverage Skipping enzymes  malabsorption & sticky stools Talk to your team about any change in stooling Good hydration! Increase with exercise/summer months Consistent bowel regimen Goal for 2-3 stools/day, type #3-4 Dietary changes Good blood sugar control in diabetic patients

10. + Impact on Nutrition May create fear of food intake after episode May require several days of NPO (nothing by mouth) until impaction clears Weight loss, malnutrition, muscle mass loss Change in diet to help manage symptoms/prevent DIOS Higher fiber diet OR lower fiber diet (based on symptoms/individual  work with your dietitian!) Increase hydration on a daily basis May require change in enzyme regimen to prevent malabsorption

11. + Why do I need to talk about my stool every clinic visit? Assessing stooling behaviors  assess potential for constipation or DIOS Assessing adequacy & appropriateness of enzyme regimen Taking at correct timing? Taking appropriate dose? Taking with correct foods? Assessing adequacy of bowel regimen What dose works for you? Prevention of DIOS!

12. + When to call your medical team Increasing abdominal pain, especially in right lower abdomen Decreased number or frequency of stools OR no stool in 24 hours Decreased appetite, feeling of abdominal “fullness,” nausea/vomiting Abdominal distention

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14. + References Cystic Fibrosis Foundation. Use the right gastrointestinal medications. (2014). https://www.cff.org/Living-with-CF/Treatments-and-Therapies/Nutrition/Use- the-Right-Gastrointestinal-Medications/ Declercq, D. & Van Biervliet, S. Nutrition and pancreatic enzyme intake in patients with cystic fibrosis with distal intestinal obstructive syndrome. (2014). Nutrition in Clinical Practice, (30)1, 134-137.Houwen, R. et al. Defining DIOS and constipation in cystic fibrosis with a multicentre study on the incidence, characteristics, and treatment of DIOS. (2009), Journal of Pediatric Gastroenterology and Nutrition. Schindler, T. & Michel, S. Nutrition Management of Cystic Fibrosis in the 21st Century. (2015). Nutrition in Clinical Practice. Van der Doef, H.P, Kokke, F.T., Van der Ent, C.K., Houwen, R.H. Intestinal Obstruction Syndrome and Constipation. (2011). Current Gastroenterology Reports. (13)3, 265- 270. Yale School of Medicine, Pediatric Respiratory Medicine. Distal intestinal obstructive syndrome (DIOS): Information sheet. (2009).