[652] Calretinin Immunostaining as an Adjunct in the Diagnosis to Hirschsprung Disease

SK Holland, P Ramalingam, RH Pololsky, M Reid-Nicholson, JR Lee. Medical College of Georgia, Augusta, GA; Charlie Norwood VAMC, Augusta, GA

Background: Calretinin immunostaining in Hirschsprung Disease (HD) has recently been reported. Earlier this year, Kapur, et al compared calretinin immunostaining with acetylcholinesterase staining and determined that calretinin is potentially superior (Pediatr Dev Pathol 12:6). They found differential calretinin staining within intrinsic nerve fibers (INFs) in HD and non-HD. They also suggested that positive calretinin staining may avoid repeat biopsies in cases that appear to have been obtained from the physiologic aganglionic segment.
Design: Our cohort of HD cases has been previously reported (Mod Path 22:133A). 4 patients with ganglion cells (GCs) had neural hypertrophy (NH)(> 40 μm diameter), and 6 patients that required repeat biopsies due to transitional or low columnar mucosa. Paraffin blocks with diagnostic material were retrieved on 23 patients with proven HD, 4 patients with GCs and NH, 14 randomly selected patients with GCs, and the original biopsies on 5 patients that required repeat biopsies. Replicate slides were immunostained with calretinin. Four pathologists scored each case for the presence of INFs and the presence of GCs. The difference in scores was assessed using logistic regression with case/control status for Hirschsprung disease as the dependent variable and number of pathologists scoring positive as the independent variable.
Results: All patients with HD were negative for INFs. 83% of non-HD immunos were deemed positive by 3 or 4 pathologists.

	Number of Pathologist saying "YES" to presence of intrinsic nerves
Number	0	1	2	3	4
Hirschsprung	23	0	0	0	0
Non-Hirschsprung	2	1	1	4	15

p=<.0001

80% of the original biopsies deemed insufficient for diagnosis were positive for INFs by 3 or 4 pathologists. All four of the cases with GCs and NH had INF. 3 or 4 pathologist identified GCs in 70% of non-HD cases. One pathologist interpreted light staining of individual cells as GCs in 2 cases of HD. Based on statistical analysis, the association between disease status and pathologist rating was significant (p < 0.0001), with a specificity of 0.83 (95% CI: 0.60, 0.94) and a sensitivity of 1 (95% CI: 0.821902, 1).
Conclusions: Calretinin immunostaining appears to be a credible adjunctive modality in the diagnosis of HD, particularly in cases that are suspicious for sampling of the aganglionic segment.
Category: Gastrointestinal

Monday, March 22, 2010 11:45 AM

Platform Session: Section E, Monday Morning