Acquired segmental colonic hypoganglionosis in an adult Caucasian male: A case report

Figure 1 Coronal slice of computed tomography scan of abdomen (with intravenous contrast in portal venous phase) demonstrating colitis affecting the descending and sigmoid colon.

Figure 2 Colonoscopy revealed confluent mucosal ulceration. A: Confluent mucosal inflammation and ulceration of the sigmoid colon observed at endoscopy; B: Mucosal necrosis of the sigmoid colon confirmed at endoscopy.

Figure 3 Operative specimen after fixation in formalin. The segment of colon on the left displays mural thickening, luminal stenosis and exposed submucosa secondary to the mucosa being denuded. There is a sharp transition to relatively normal colon on the right, with intact mucosal folds being observed.

Figure 4 Haematoxylin and eosin stain staining result. A: Hypertrophy of the inner circular layer of the muscularis propria (magnification × 40); B: Hypertrophy and fibrosis of the muscularis mucosae extending into the muscularis propria (magnification × 40).

Figure 5 Haematoxylin and eosin stain staining result. A: Hypertrophic nerves with a lack of mature ganglion cells in the myenteric plexus (magnification × 400); B: Hypertrophic nerve with one isolated mature ganglion cell in myenteric plexus (arrow) (magnification × 400).

Figure 6 Calretinin staining. A: Low-power (magnification × 40) calretinin staining of nerve in diseased colon showing one isolated mature ganglion cell (dark brown cell, arrow) and markedly reduced density (0.2/mm²); B: Low-power (magnification × 40) calretinin staining of normal colon showing normal density (5/mm²) of mature ganglion cells (numerous dark brown cells); C: High-power (magnification × 400) calretinin stain in diseased colon showing failure of immature ganglion cells to stain (pale brown cells); D: High-power (magnification × 400) calretinin staining of normal colon showing abundance of mature ganglion cells (dark brown cells).