改良型ムトー式直腸粘膜吸引生検鉗子による直腸生検の検討

抄録

The rectal mucosal biopsy and histochemical examination of the specimen by acetylcholinesterase staining are essential for the diagnosis of aganglionosis. However, this histochemical examination has been used in only 30% of the pediatric institutions in Japan. One of the reason for the infrequent performance of the histochemical study might be the lack of suitable instruments for the biopsy. Mutoh's suction biopsy forceps, which had been developed for adults, were reformed for children and were used in a screening study of constipated patients. One hundred and two specimens were obtained from 51 patients, which consisted of 30 patients with chronic constipation, 9 with aganglionosis, and other allied disorders. Biopsied specimen must contain the muscularis mucosae for correct interpretation, because nerve proliferation can be observed in the lamina propria in certain normoganglionic conditions. The specimens were obtained adequately in 98% of the patients by using this instrument. Five percent of specimens obtained from patients with chronic constipation was inadequate for correct interpretation. In contrast, specimens from the postoperative patients were inadequate in 33% for diagnosis. The confirmation of the ganglion cells was non-essential in 90% of the patients in whom nerve proliferation in the muscularis mucosae was reliable for differential diagnosis between normo- and aganglionosis. In the remaining patients, 10%, which showed a small number of nerve fibers with low activity of AChE in both normo- and aganglionic specimens, the ganglion cells had to be identified for diagnosis. In conclusion, the rectal mucosal biopsy by the reformed Mutoh's forceps was useful in obtaining adequate specimens. Only 2.1% of the patients had inadequate specimens.