Perianal fistulas

Furthermore, the inflammation may be transmural, penetrating to the muscularis or serosal layers of the GI tract (Fig. 16-2). The propensity for transmural involvement may lead to serious complications of CD, such as strictures, listulae, and abscesses.4,12 While rectal inflammation is typically less common in CD than UC, several types of perianal lesions may be observed in patients with CD. These include skin tags, hemorrhoids, fissures, anal ulcers, abscesses, and fistulae.15... 

Crohn s disease Fever, tachycardia (with severe disease), dehydration, arthritis, abdominal mass and tenderness, perianal fissure or fistula... 

Antibiotics have been studied based on the rationale that they may interrupt the inflammatory response directed against endogenous bacterial flora. Metronidazole and ciprofloxacin have been the two most widely-studied agents.32 Metronidazole may benefit some patients with pouchitis (inflammation of surgically-created intestinal pouches) and patients with CD who have had ileal resection or have perianal fistulas. Ciprofloxacin has shown some efficacy in refractory active CD. Both drugs may cause diarrhea, and long-term use of metronidazole is associated with the development of peripheral neuropathy. 

Cyclosporine is not recommended for Crohn s disease except for patients with symptomatic and severe perianal or cutaneous fistulas. The dose of cyclosporine is important in determining efficacy. An oral dose of 5 mg/kg/ day was not effective, whereas 7.9 mg/kg/day was effective. However, toxic effects limit application of the higher dosage. Dosage should be guided by cyclosporine whole-blood concentrations. 

She has no other significant medical or surgical history. Her current medications are mesalamine 2.4 g/d and budesonide 9 mg/d. She appears thin and tired. Abdominal examination reveals tenderness without guarding in the right lower quadrant a mass is not palpable. On perianal examination, there is no tenderness, fissure, or fistula. 

Lowry, P. W., Weaver, A. L., Tremaine, W. J., and Sandbom, W. J. (1999). Combination therapy with oral tacrolimus (FK506) and azathioprine or 6-mercaptopurine for treatment-refractory Crohn s disease perianal fistulae. Inflam. Bowel Dis. 5, 239-245. 

Antibiotics can be used as either (1) adjunctive treatment along with other medications for active IBD (2) treatment for a specific complication of Crohn s disease or (3) prophylaxis for recurrence in postoperative Crohn s disease. Metronidazole, ciprofloxacin, and clarithromycin are the antibiotics used most frequently. They are more beneficial in Crohn s disease involving the colon than in disease restricted to the Ueum. Specific Crohn s disease-related complications that may benefit from antibiotic therapy include intra-abdominal abscess and inflammatory masses, perianal disease (including fistulas and perirectal abscesses), small bowel bacterial overgrowth secondary to partial small bowel obstruction, secondary infections with organisms such as Clostridium difficile, and postoperative complications. Metronidazole may be particularly effective for the treatment of perianal disease. Postoperatively, a 3-month course of metronidazole (20 mg/kg/day) can prolong the time to both endoscopic and clinical recurrence. 

Metronidazole is used increasingly as primary therapy for pseudomembranous colitis due to Clostridium difficile infection. At doses of250-500 mg orally three times daily for 7-14 days, metronidazole is effective and less expensive than oral vancomycin. Metronidazole also is used in patients with Crohn s disease who have perianal fistulas or significant colonic disease fsee Chapter 38). 

CT, fibrofatty proliferation shows a slightly increased attenuation. In MRl, the signal intensity is decreased compared with normal fat separating the bowel loops. Phlegmon and abscesses can occur in the small bowel mesentery, abdominal wall, or psoas muscle or perianally. They are well demonstrated on CT and fat-saturated TlW MR imaging [59]. Fistulas and sinus tracts are also depicted however, the reported sensitivity of MR imaging for depicting sinus tracts is 50%-75% compared to a conventional enteroclysis study [63]. 

Of special interest in this group of youngsters has been the response of severe rectal and perianal disease to total parenteral nutrition. In one boy (R.G.) who failed to respond to several operations, his upper intestinal tract remission has been accompanied by complete healing of multiple perianal fistulae. In the girl (M.P.) who had an ileocolectomy and post operative parenteral nutrition, multiple perianal fistulae have healed. In this patient the effect of resection of intra-abdominal disease must be considered, but the rapidity of the perineal improvement was similar to that noted for R.G. Lastly, I.W. with severe anal granulomata and ulcers sustained marked improvement of the anal involvement after a brief course of parenteral alimentation. 

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