Table of Contents

 

Managing acute flares of chronic inflammatory bowel disease (IBD) in the ED can be challenging. This issue will help you:

Differentiate the routine flare from a complication

Learn the extraintestinal manifestations of undiagnosed IBD to help spot the disease early

Determine whether the signs and symptoms indicate an infectious etiology

Order laboratory testing and imaging that will be most effective and helpful

Identify surgical emergencies

Communicate effectively with gastroenterologists and assist in long-term management

Offer patients information and resources that will help them cope with long-term implications of the disease

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Etiology and Pathophysiology
   1. Crohn Disease
   2. Ulcerative Colitis
   3. Indeterminate Colitis
   4. Extraintestinal Manifestations
      1. Nephrolithiasis
      2. Gall Bladder Disease
      3. Osteoporosis/Osteopenia
      4. Atherosclerosis
      5. Primary Sclerosing Cholangitis
   5. Thromboembolic Risks
   6. Inflammatory Bowel Disease Prognosis
6. Differential Diagnosis
7. Prehospital Care
8. Emergency Department Evaluation
   1. Clinical Presentation
   2. History and Physical Examination
9. Diagnostic Studies
   1. Laboratory Testing
      1. C-Reactive Protein and Erythrocyte Sedimentation Rate Testing
      2. Fecal Calprotectin
   2. Imaging Studies
      1. Using Disease Phenotype and Imaging in Decision-Making
      2. Computed Tomography
         • Computed Tomographic Enterography
      3. Magnetic Resonance Imaging and Magnetic Resonance Enterography
      4. Ultrasonography
      5. Inpatient Endoscopy
   3. Clinical Decision Rules
10. Treatment
    1. Acute Flares
    2. Surgical Emergencies and Surgical Treatment in Crohn Disease
       1. Small Bowel
       2. Colon
       3. Anorectal
    3. Surgical Emergencies and Surgical Treatment in Ulcerative Colitis
    4. Medical Management Strategies
    5. Long-Term Implications of Inflammatory Bowel Disease
       1. Malignancy
          • Surveillance Colonoscopy
       2. Psychosocial Effects
11. Special Populations
    1. Pediatric Patients
12. Cutting Edge
13. Disposition
14. Summary
15. Key Points
16. Risk Management Pitfalls for Inflammatory Bowel Disease Flares
17. Time- and Cost-Effective Strategies
18. Case Conclusions
19. Clinical Pathway for Inflammatory Bowel Disease Patients Presenting With Abdominal Pain
20. Tables and Figures
    1. Table 1. Extraintestinal Manifestations of Inflammatory Bowel Disease
    2. Table 2. Differential Diagnosis of an Inflammatory Bowel Disease Flare
    3. Table 3. Medications for Inflammatory Bowel Disease
    4. Figure 1. Magnetic Resonance Enterography of Bowel, Showing Evidence of Crohn Disease
    5. Figure 2. Ultrasound of Perianal Fistula
    6. Figure 3. Radiograph of Toxic Megacolon
21. References

Abstract

Because of the chronic relapsing nature of inflammatory bowel disease (IBD), emergency clinicians frequently manage patients with acute flares and complications. IBD patients present with an often-broad range of nonspecific signs and symptoms, and it is essential to differentiate a mild flare from a life-threatening intra-abdominal process. Recognizing extraintestinal manifestations and the presence of infection are critical. This issue reviews the literature on management of IBD flares in the emergency department, including laboratory testing, imaging, and identification of surgical emergencies, emphasizing the importance of coordination of care with specialists on treatment plans and offering patients resources for ongoing support.

Case Presentations

At the start of your shift, you log on and click into your first ED chart of the day and sigh, “Not again.” It’s the chart of one of your “frequent flyers,” a young woman who has come to the ED several times in the past few months with a variety of nonurgent complaints. Itching eyes is one. “I seem to be tired all the time,” is another. “I have fevers sometimes.” “My muscles ache. My joints hurt sometimes.” Her workups are always unrevealing. She carries multiple diagnoses, many nonspecific: anemia, possible depression, medication-seeking behavior, myalgias, possible malingering, etc. Today’s chief complaint is abdominal pain. “It's going to be a heck of a day, if this is the start of it,” you think, but remembering how bias can cloud decision-making, you take a deep breath and enter the exam room...

Your next patient is a 40-year-old man with long-standing ulcerative colitis, well known to your institution, who has come in many times for UC flares. Today though, his first words to you are, “I’m sicker than usual.” Glancing at his chart, you notice that he has a fever and a heart rate of 117 beats/min. He looks moderately ill, although it’s hard to assess him completely, since he is fully clothed and clutching his belly, hunched over and groaning. You recall that this is not entirely different from many other ED visits for this patient. You wonder how to sort through his presentation. Is this just another UC flare … or something more sinister?

Introduction

Crohn disease (CD) and ulcerative colitis (UC) are the 2 major forms of inflammatory bowel disease (IBD). CD can affect any portion of the alimentary tract, from the mouth to the anus, and is a transmural process. UC, as the name implies, affects the colon’s mucosal lining. A 2004 literature review estimated that 1.4 million people in North America and 2.2 million in Europe have IBD.¹ It is highly likely that there are many people with IBD who are undiagnosed. Approximately 25% of IBD patients are diagnosed in their first 2 decades of life, with an increased incidence reported in teens.^2,3

The annual number of emergency department (ED) visits in the United States for IBD-related complaints is unknown. However, due to IBD’s chronic relapsing nature and the complications associated with the condition, the public health burden of disease is substantial.⁴ Per the Crohn’s & Colitis Foundation website,⁵ there were 1.1 million ambulatory care visits for CD and another 716,000 for UC in 2004. The same site estimates that the annual financial burden of IBD in the United States is over $31 billion.

Because patients with IBD often present to the ED acutely decompensating, the emergency clinician must have a systematic approach to evaluation and management and must be familiar with therapeutic strategies needed to stabilize the patient. More challenging is the patient with undiagnosed IBD, and familiarity with the symptom complex and diagnostic criteria can help ensure that these patients receive the specialty care they need. This issue of Emergency Medicine Practice provides a systematic review of the literature on IBD, with best-practice recommendations incorporating advances in diagnostics and therapeutics.

Critical Appraisal of the Literature

There is a vast and rapidly growing body of IBD literature, but most of it has been published outside of traditional emergency medicine journals. To focus on the IBD literature relevant to emergency practice, we limited most of our review to literature published since 2006 and crossed the terms inflammatory bowel disease with the search terms emergency, complications, treatment, and emergency department. Adding [AND] emergency to the original inflammatory bowel disease PubMed search string produced 20 references, 13 within the last 10 years, with 2 from the emergency medicine literature. In addition to PubMed searches, the Cochrane Database of Systematic Reviews, the National Guidelines Clearinghouse, and various gastrointestinal medical society websites and patient-centered IBD websites were searched. These sources provided articles primarily on long-term care and other nonemergent IBD-related issues. However, a great deal of useful information on acute IBD flares was gleaned from guidelines provided on the American Gastroenterological Association website (www.gastro.org). Where prospective randomized studies were available and relevant to ED care, we attempted to preferentially present data from these studies.

Risk Management Pitfalls for Inflammatory Bowel Disease Flares

1. “He came in with painful bumps on his shins, anemia, and some joint pain; how was I to know it was IBD?”

The painful shin bumps may be erythema nodosum, a dermatologic manifestation of IBD. Anemia, which may be multifactorial, often coexists with IBD. Finally, musculoskeletal manifestations are perhaps the most common of the extraintestinal manifestations of IBD. These findings and many others often coexist with, and flare with, IBD disease activity.

2. “I give antibiotics to every IBD patient with a disease flare.”

Consider checking with your patient’s gastroenterologist, but try to save the antibiotics to treat those with a high likelihood of, or proof of, a bacterial infection. Infectious colitis, toxic megacolon, bowel perforation, intra-abdominal abscess and other infections (pyelonephritis, cholecystitis) are indications for antibiotics. Admittedly, it can be difficult to distinguish a “flaring” patient from an infected one, since both may have temperature elevations and laboratory findings indicating possible infection. Flare due to infection or coexisting with infection is possible as well.

3. “I can’t CT everyone with abdominal pain and bloody stools.”

That’s a true statement, nor should you obtain a CT on every IBD patient with abdominal pain and bloody stools. However, certain IBD patients need imaging, and CT may the most expeditious way to get the information you need to care for these individuals. Consider CT (or alternate imaging, if feasible) in IBD patients for whom there is a concern for IBD-related surgical emergencies or other abdominopelvic but non- IBD-related diagnoses: for example, patients with severe pain and signs of sepsis.

4. “All the lab results are normal; she can’t have IBD.”

Many laboratory abnormalities are associated with IBD, IBD flares, medications effects, and disease complications. However, normal laboratory results, while perhaps reassuring, do not rule out IBD.

5. “IBD is rare in children.”

It is not rare at all: about 25% of IBD diagnoses are made in the pediatric age group. Include IBD in the differential diagnosis of children with aphthous ulcers, arthritic complaints, and growth delay, and refer them for workup.

6. “It was just a urinary tract infection. I didn’t know she’d bounce back to the ED septic.”

IBD patients are immunocompromised, and as a result, they are at increased lifetime risk for infections, sepsis, and end-organ failure. Infectious complications are a major cause of mortality in IBD patients. Be extra careful with IBD patients who have concurrent infections. A brief “admit for observation” may be a helpful strategy in this group, even if they’re not particularly ill-appearing.

7. “I’ve never seen a patient with toxic megacolon. How would I even know to suspect it?”

Broadly defined, toxic megacolon is a nonobstructive colonic dilation alongside systemic toxicity. As you assess sicker IBD patients in the ED (and those with toxic megacolon will be among the sickest IBD patients you will see) look for signs of sepsis, marked vital sign abnormalities consistent with shock, dehydration, anemia, and leukocytosis. Consider stat acute abdominal series radiographs. A toxic patient with colonic dilation ≥ 6 cm on a supine abdominal radiograph should alert you to the diagnosis.

8. “There are so many IBD medications now, I can’t keep them all straight.”

A general understanding of the 5 broad medication classes as outlined in this review will be helpful, along with a few facts about the major adverse effects one can see with some of the medications. Corticosteroids remain the cornerstone of IBD flare therapy. Oral corticosteroids can be used for mild outpatient flares. High-dose intravenous corticosteroids are used for the sicker admitted patients.

9. “The easiest and best way for me to treat IBD patients with abdominal pain is to check all the labs, rehydrate, treat pain, and do a CT.”

That may be a completely reasonable and necessary approach, but only for a subset of IBD patients. All IBD patients in the ED do not need the same workup, particularly the CT.

10. “Aside from opioids, there are no other medications to treat IBD symptoms.”

Dehydration is miserable, but it is easily treated with either oral or intravenous rehydration. Fever and nausea cause misery as well. Both can generally be treated to resolution in the ED. Consider benzodiazepines for tenesmus (and anxiety, if that is an issue). Consider also the potential opioid-sparing effect of ketamine, a medication with almost no absolute contraindications.

Tables and Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the authors, are noted by an asterisk (*) next to the number of the reference.

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3. Molodecky NA, Soon IS, Rabi DM, et al. Increasing incidence and prevalence of the inflammatory bowel diseases with time, based on systematic review. Gastroenterology. 2012;142(1):46-54. (Review)
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18. Varda BK, McNabb-Baltar J, Sood A. et al. Urolithiasis and urinary tract infection among patients with inflammatory bowel disease: a review of US emergency department visits between 2006 and 2009. Urology. 2015;85(4):764-770. (Retrospective; 14,352 patients)
19. Zhang FM, Xu CF, Shan GD, et al. Is gallstone disease associated with inflammatory bowel diseases? A meta-analysis. J Dig Dis. 2015;16(11):634-641. (Meta-analysis; 5 studies)
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22. Lindor KD, Kowdley KV, Harrison ME; American College of Gastroenterology. ACG clinical guideline: primary sclerosing cholangitis. Am J Gastroenterol. 2015;110(5):646-659. (Review and clinical guideline)
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29. * Huang M, Rose E. Pediatric inflammatory bowel disease in the emergency department: managing flares and long-term complications. Pediatr Emerg Med Pract. 2014;11(7):1-20. (Review)
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34. Poullis AP, Zar S, Sundaram KK, et al. A new, highly sensitive assay for C-reactive protein can aid the differentiation of inflammatory bowel disorders from constipation-and diarrhoea-predominant functional bowel disorders. Eur J Gastroenterol Hepatol. 2002;14(4):409-412. (Prospective; 224 patients)
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36. Vermeire S, Van Assche G, Rutgeerts P. Laboratory markers in IBD: useful, magic, or unnecessary toys? Gut. 2006;55(3):426-431. (Review)
37. Fagan EA, Dyck RF, Maton PN, et al. Serum levels of C-reactive protein in Crohn’s disease and ulcerative colitis. Eur J Clin Invest. 1982;12(4):351-359. (Prospective; 104 patients)
38. van Rheenen PF, Van de Vijver E, Fidler V. Faecal calprotectin for screening of patients with suspected inflammatory bowel disease: diagnostic meta-analysis. BMJ. 2010;15(341):c3369. (Meta-analysis; 6 adult studies [n=670], 7 pediatric studies [n=371])
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40. Griffey RT, Fowler KJ, Theilen A, et al. Considerations in imaging among emergency department patients with inflammatory bowel disease. Ann Emerg Med. 2017;69(5):587-599. (Review)
41. Quezada SM, Cross RK, Association of age at diagnosis and ulcerative colitis phenotype. Dig Dis Sci. 2012;57(9):2402-2407. (Retrospective; 260 patients)
42. Gasche C, Grundtner P. Genotypes and phenotypes in Crohn’s disease: do they help in clinical management? Gut. 2005;54(1):162-167. (Review)
43. Paulsen SR, Huprich JE, Fletcher JG, et al. CT enterography as a diagnostic tool in evaluating small bowel disorders: review of clinical experience with over 700 cases. Radiographics. 2006;26(3):641-657. (Review)
44. Bodily KD, Fletcher JG, Solem CA, et al. Crohn disease: mural attenuation and thickness at contrast-enhanced CT enterography--correlation with endoscopic and histologic findings of inflammation. Radiology. 2006;238(2):505-516. (Retrospective; 96 patients)
45. Ahmed O, Rodrigues DM, Nguyen GC. Magnetic resonance imaging of the small bowel in Crohn’s disease: a systematic review and meta-analysis. Can J Gastroenterol Hepatol. 2016(2016):7857352. (Meta-analysis; 19 studies, 1020 patients)
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47. Govani SM, Guentner AS, Waljee AK, et al. Risk stratification of emergency room patients with Crohn’s disease could reduce computed tomography use by nearly half. Clin Gastroenterol Hepatol. 2014;12(10):1702-1707. (Retrospective; 613 patients)
48. Jung YS, Park DI, Hong SN, et al. Predictors of urgent findings on abdominopelvic CT in patients with Crohn’s disease presenting to the emergency department. Dig Dis Sci. 2015;60(4):929-935. (Retrospective; 266 CTs done)
49. Yarur AJ, Mandalia AB, Dauer RM, et al. Predictive factors for clinically actionable computed tomography findings in inflammatory bowel disease patients seen in the emergency department with acute gastrointestinal symptoms. J Crohn’s Colitis. 2014;8(6):504-512. (Cross-sectional study; 354 patients)
50. Kerner C, Carey K, Mills AM, et al. Use of abdominopelvic computed tomography in emergency departments and rates of urgent diagnoses in Crohn’s disease. Inflamm Bowel Dis. 2013;9(6):1179-1185. (Retrospective; 648 adults)
51. * Sandborn WJ. Crohn’s disease evaluation and treatment: clinical decision tool. Gastroenterology. 2014;147(3):702-705. (Consensus management guideline)
52. Panaccione R, Colombel JF, Louis E, et al. Evolving definitions of remission in Crohn’s disease. Inflamm Bowel Dis. 2013;19(8):1645-1653. (Review, opinion)
53. * Hwang JM, Varma MG. Surgery for inflammatory bowel disease. World J Gastroenterol. 2008;14(17):2678-2690. (Review)
54. Gardiner KR, Desari BV. Operative management of small bowel Crohn’s disease. Surg Clin North Am. 2007;87(3):587-610. (Review)
55. Hurst RD, Molinari M, Chung TP, et al. Prospective study of the features, indications, and surgical treatment in 513 consecutive patients affected by Crohn’s disease. Surgery. 1997;122(4):661-667. (Prospective; 513 patients)
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57. Fonseca AL, Schuster KM, Maung AA, et al. Routine nasogastric decompression in small bowel obstruction: is it really necessary? Am Surg. 2013;79(4):422-428. (Retrospective chart review; 290 patients)
58. Broe PJ, Bayless TM, Cameron JL. Crohn’s disease: are enteroenteral fistulas an indication for surgery? Surgery. 1982;91(3):249-253. (Retrospective; 64 patients)
59. Present DH, Rutgeerts P, Targan S, et al. Infliximab for the treatment of fistulas in patients with Crohn’s disease. N Engl J Med. 1999;340:1398-1405. (Randomized, double-blind, multicenter, placebo-controlled; 94 patients)
60. Sands BE, Anderson FH, Bernstein CN, et al. Infliximab maintenance therapy for fistulizing Crohn’s disease. N Engl J Med. 2004;350(9):876-885. (Multicenter double-blind randomized placebo-controlled; 306 patients)
61. Ribeiro MB, Greenstein AJ, Yamazaki Y, et al. Intra-abdominal abscesses in regional enteritis. Ann Surg. 1991;213(1):32-36. (Retrospective; 610 patients)
62. Garcia JC, Persky SE, Bonis PA, et al. Abscesses in Crohn’s disease: outcome of medical versus surgical treatment. J Clin Gastroenterol. 2001;32(5):409-412. (Retrospective; 51 patients)
63. Gutierrez A, Lee H, Sands BE. Outcome of surgical versus percutaneous drainage of abdominal and pelvic abscesses in Crohn‘s disease. Am J Gastroenterol. 2006;101(10):2283-2289. (Prospective; 66 patient encounters)
64. Kronberger IE, Graziadei IW, Vogel W. Small bowel adenocarcinoma in Crohn’s disease: a case report and review of literature. World J Gastroenterol. 2006;12(18):1317-1320. (Case report with literature review)
65. Yamamoto T. Factors affecting recurrence after surgery for Crohn’s disease. World J Gastroenterol. 2005;11(26):3971-3979. (Review)
66. Collins PD, Mpofu C, Watson AJ, et al. Strategies for detecting colon cancer and/or dysplasia in patients with inflammatory bowel disease. Cochrane Database Syst Rev. 2006;CD000279. (Systematic review)
67. Solomon MJ. Fistulae and abscesses in symptomatic perianal Crohn’s disease. Int J Colorectal Dis. 1996;11(5):222-226. (Prospective)
68. Fleshner PR, Schoetz DJ Jr, Roberts PL, et al. Anal fissure in Crohn’s disease: a plea for aggressive management. Dis Colon Rectum. 1995;38(11):1137-1143. (Retrospective; 66 patients)
69. Wolkomir AF, Luchtefeld MA. Surgery for symptomatic hemorrhoids and anal fissures in Crohn’s disease. Dis Colon Rectum. 1993;36(6):545-547. (40 patients)
70. Grucela A, Steinhagen RM. Current surgical management of ulcerative colitis. Mt Sinai J Med. 2009;76(6):606-612. (Review)
71. Cohen JL, Strong SA, Hyman NH, et al; Standards Practice Task Force American Society of Colon and Rectal Surgeons. Practice parameters for the surgical treatment of ulcerative colitis. Dis Colon Rectum. 2005;48(11):1997-2009. (Management guideline)
72. Metcalf AM. Elective and emergent operative management of ulcerative colitis. Surg Clin North Am. 2007;87(3):633-641. (Review)
73. Truelove SC, Witts LJ. Cortisone in ulcerative colitis: final report on a therapeutic trial. Br Med J. 1955;2(4947):1041-1048. (Preliminary report; historical)
74. * Vadivelu N, Schermer E, Kodumudi V, et al. Role of ketamine for analgesia in adults and children. J Anaesthesiol Clin Pharmacol. 2016;32(3):298-306. (Review)
75. Lichtenstein L, Ron Y, Kivity S, et al. Infliximab-related infusion reactions: systematic review. J Crohn's Colitis. 2015;9(9):806-815. (Systematic review)
76. Wilson JC, Furlano RI, Jick SS, et al. A population-based study examining the risk of malignancy in patients diagnosed with inflammatory bowel disease. J Gastroenterol. 2016;51(11):1050-1062. (Registry study; 39,294 patients)
77. Singh S, Nagpal SJ, Murad MH, et al. Inflammatory bowel disease is associated with an increased risk of melanoma: a systematic review and meta-analysis. Clin Gastroenterol Hepatol. 2014;12(2):210-218. (Systematic review, meta-analysis; 12 studies, 172,837 patients)
78. Pedersen N, Duricova D, Elkjaer M, et al. Risk of extra-intestinal cancer in inflammatory bowel disease: meta-analysis of population-based cohort studies. Am J Gastroenterol. 2010;105(7):1480-1487. (Meta-analysis; 8 studies, 17,052 patients)
79. * American Gastroenterological Association. Managing CRC Risk in IBD Patients. Available at: http://www.gastro.org/guidelines/managing-CRC-risk-in-IBD-patients-1. Accessed October 10, 2017. (Practice management guideline)
80. Regueiro M, Greer JB, Szigethy E. Etiology and treatment of pain and psychosocial issues in patients with inflammatory bowel diseases. Gastroenterology. 2017;152(2):430-439. (Review)
81. Szigethy E, McLafferty L, Goyal A. Inflammatory bowel disease. Child Adolesc Psychiatr Clin N Am. 2010;19(2):301-318. (Review)
82. Rosenblatt E, Kane S. Sex-specific issues in inflammatory bowel disease. Gastroenterol Hepatol (NY). 2015;11(9):592-601. (Review)
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