Quantification of Interstitial Cells of Cajal in the Gastric Muscles of Patients With or Without Gastroparesis

Introduction: Interstitial cells of Cajal (ICC) are involved in the transmission of neuronal signaling to the smooth muscles of the GI tract, thereby acting as a pacemaker. They have previously been implicated in the pathogenesis of GI motility disorders. Gastroparesis (Gp) is 1 such disorder in which slow-wave electric activity has shown to be impaired. Our prior study reported gastric ICC numbers in patients with gastroparesis. However, there has not been a comparison with normal gastric muscle samples. To our knowledge, this is the first study to directly quantify and examine the ICC in gastric antral muscle samples in patients with or without gastroparesis. Methods: Patients with a confirmed diagnosis of gastroparesis via a nuclear medicine gastric emptying study who underwent a planned Gastric Per-Oral Endoscopic Myotomy (GPOEM) were enrolled in this study from October 2022 to January 2023. Autopsy gastric specimens of healthy adult population served as controls from September 2022 to November 2022. ICC from gastric antral muscle samples was examined and quantitated in a 4mm2 area. A 2 sample T-test was used to determine statistical significance between ICC in patients with or without gastroparesis (Table 1). Results: 16 patients with gastroparesis were enrolled and compared with 16 control specimens. There were 5 females in the control group and 13 females in the gastroparesis group. The mean age of patients in control group was 40yrs and gastroparesis group was 55yrs. The average BMI of patients in control group was 29.2kg/m2 and gastroparesis group was 35.2kg/m2. The average number of ICC in gastroparesis population was significantly lower than control group (317.0 ± 199.9 vs. 1394.64 ± 314.6cells per 4mm2 area; P value < 0.0001). The cause of gastroparesis patients was due to diabetes (11 patients), idiopathic (2) and post-surgical (3). Conclusion: This study provides a reliable conclusion that Interstitial cells of Cajal are significantly lowered in gastroparesis patients when directly compared with healthy adult population even though the age and gender of the 2 groups were not the same in the 2 group. However, further studies with larger number of patients are needed to confirm the results. Table 1. - Data for quantification of Interstitial cells of Cajal between patient with or without gastroparesis Control Gastroparesis Gender Females 5 13 Males 11 3 Race White 7 10 African American 9 5 Other 1 Age (yrs) Average 40 ± 15 55 ± 12 BMI (kg/m2) vAverage 29.2 ± 8.8 35.2 ± 4.7 Number of ICC cells (per 4mm2 area) 1394.6 ± 314.6 371.0 ± 199.9 Cause of Gastroparesis Diabetes Mellitus 11 Idiopathic 2 Post-surgical 3