[569] Histologic Evaluation of Excised Pouch Specimens in Distinguishing Crohn's Disease of the Pouch (CDP) from Chronic Antibiotic-Refractory Pouchitis (CARP)
T DeRoche, B Shen, F Remzi, V Fazio, AE Bennett, JR Goldblum. Cleveland Clinic, Cleveland, OH; Gastroenterology; Colorectal Surgery
Background: Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the treatment of choice in pts with presumed ulcerative colitis/ indeterminate colitis who require surgical excision. IPAA is generally contraindicated in pts with Crohn's disease, due to a higher risk of pouch failure. Some IPAA pts develop poorly functioning pouches requiring excision; common causes of pouch failure include CDP and CARP. The aim of this study was to determine whether histologic features could reliably distinguish between pts with a clinical diagnosis of CDP and CARP.
Design: Our institutional pouchitis database was used to identify pts with a clinical diagnosis of CDP or CARP who underwent pouch excision. The diagnosis of CDP was based on a combined assessment of clinical, endoscopic, radiographic, and histologic features as well as prior response to anti-TNF therapy. CARP was defined as failure to respond to a 4-week course of a single antibiotic, requiring prolonged therapy of 
4 weeks. We evaluated 16 cases of CDP and 10 cases of CARP for neutrophil infiltration, ulceration, villous blunting, crypt distortion, and mononuclear cell and eosinophil infiltration of the lamina propria (0-3+). Cases were also evaluated for the presence of granulomas, pyloric gland metaplasia, intraepithelial lymphocytosis, transmural inflammation, and fistulae.
Results: CDP group included 9 males and 7 females, age 23-50 years (mean 38.0 years). CARP group included 4 males and 6 females, age 44-70 years (mean 57.2 years).
| CDP (N=16) Mean score, 0-3 scale | CARP (N=10) Mean score, 0-3 scale | P value | |
| Neutrophilic infiltration | 1.12 | 1.6 | 0.27 |
| Ulcer | 2.19 | 1.9 | 0.51 |
| Villous blunting | 1.87 | 1.05 | 0.76 |
| Crypt distortion | 1.37 | 1.6 | 0.58 |
| Mononuclear infiltration | 1.5 | 1.9 | 0.25 |
| Eosinophils | 1.37 | 0.71 | 0.67 |
| CDP (N=16) | CARP (N=10) | P value | |
| Granulomas | 3/16 | 0/10 | 0.14 |
| Pyloric gland metaplasia | 8/16 | 5/10 | 1.0 |
| Intraepithelial lymphocytes | 0/16 | 0/16 | NA |
| Transmural inflammation | 2/16 | 3/10 | 0.27 |
| Fistula | 6/16 | 0/10 | 0.049 |
Conclusions: Only fistulae were associated with a clinical diagnosis of CDP. Although granulomas were found only in CDP, this feature was seen in very few pts and was not significantly associated with CDP. All other histologic features, including transmural inflammation, were not useful in distinguishing CDP from CARP.
Category: Gastrointestinal
Wednesday, March 11, 2009 9:30 AM
Poster Session V # 68, Wednesday Morning