A comparison of suction and full-thickness rectal biopsy in children

Rectal biopsy evaluation by an experienced pathologist is the gold standard in diagnosis of Hirschsprung's disease (HD). Although both suction rectal biopsy (SRB) and full-thickness (FTRB) rectal biopsy are performed, the ability for SRB to obtain adequate tissue in older children has been questioned. We hypothesized that SRB and FTRB yield tissue specimens of different size but are equally adequate for diagnosis.

Records of children who underwent rectal biopsy to evaluate for HD between January 2007 and July 2014 were reviewed. Volume, percent submucosa, and specimen adequacy were compared between biopsy techniques, and the effect of age on biopsy adequacy was assessed. Data were analyzed by mixed-effects models with covariate adjustment for age at biopsy and Fisher's exact test.

Forty-seven children underwent a total of 58 biopsies, 45 SRB and 13 FTRB. Thirty-seven were performed before 12 mo of age, and 21 after 12 mo of age. Volume of SRB specimens was significantly smaller than FTRB across ages (14.8 ± 7.8 mm(3)versus 121.3 ± 13.8 mm(3), P = 0.0001). Percent submucosa did not differ significantly between SRB and FTRB specimens across ages (63.8 ± 2.7% versus 66.5 ± 4.3%, P = 0.575). The number of inadequate biopsies was low and not significantly different across ages (P = 0.345), or when comparing by biopsy method (P = 0.689). All biopsies were clinically diagnostic. There were no complications.

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. Differences in cost and patient satisfaction between rectal biopsy techniques must be studied to further define the best overall technique.