E. D. Muise1, S. Hardee2, R. A. Morotti2, R. A. Cowles1 1Yale University School Of Medicine,Pediatric Surgery,New Haven, CT, USA 2Yale University School Of Medicine,Pathology,New Haven, CT, USA
Introduction: Rectal biopsy with evaluation by surgical pathology is considered the most accurate test when evaluating infants and children for Hirschsprung’s Disease (HD). The biopsy site and the percentage of submucosa in the biopsy sample are felt to be important for establishing a pathologic diagnosis. The ability for certain biopsy techniques to obtain adequate tissue, especially in older children, has been questioned. While both suction (SRB) and full-thickness (FTRB) rectal biopsy are commonly employed, no studies have described and compared the quality of the tissue samples obtained using these two techniques. We hypothesized that SRB and FTRB yield tissue specimens of different size, but that these specimens are equally diagnostic after pathologic analysis.
Methods: Records of all children who underwent rectal biopsy to evaluate for HD between January 2007 and July 2014 were reviewed. Demographic data and details of the specimen and pathologic analysis were obtained. Volume of specimen, depth of submucosa, %submucosa, and diagnostic accuracy were compared between biopsy techniques and the effect of age on biopsy quality was assessed. Data were analyzed by mixed effects models with covariate adjustment for age at biopsy, and Fisher’s exact test.
Results: Forty-seven children, 28 male and 19 female, underwent a total of 58 rectal biopsies, 45 SRB and 13 FTRB. Thirty-two biopsies were performed after 12 months of age, 26 before 12 months (range 0-141months). Volume of SRB specimens was significantly smaller than FTRB across all ages (14.8mm3+/- 7.8 vs 121.3mm3 +/- 13.8, p=0.0001). Percent submucosa did not differ significantly between SRB and FTRB specimens across all ages (63.8% +/- 2.7 vs 66.5%+/-4.3, p=0.58). Volume of SRB specimens did not differ significantly when performed before or after 12 months of age (11.3mm3 +/- 2.5 vs 21.0mm3 +/-3.9, p=0.28). SRB compared with FTRB demonstrated no significant differences in volume when performed before 12 months (12.2mm3 +/-3.6 vs 58.9mm3 +/- 11.2, p=0.16), and significant differences when performed after 12 months (18.7mm3 +/-20.0 vs 150.5mm3 +/-21.9, p=0.003). However, percent submucosa in SRB and FTRB performed both before 12 months of age (64.9%+/-3.3 vs 74.8%+/-6.7, p=0.36) and after 12 months of age (62.6%+/-5.1 vs 64.9%+/-5.3, p=0.70) was not significantly different. The number of inadequate biopsies was not significantly different when performed before or after 12 months (p=0.41). The diagnostic accuracy for both SRB and FTRB was 100% and there were no complications.
Conclusions: Tissue specimens obtained by SRB are smaller than those obtained by FTRB, especially in older children. SRB and FTRB appear equivalent in their ability to provide adequate submucosa for analysis and both provide highly diagnostic tissue for evaluation. Differences in cost and patient satisfaction between these two rectal biopsy techniques should be studied to further define the best overall technique.