Appendiceal intussusception due to a fecalith mimicking a submucosal tumor

A case report of impacted fecalith within mucosal pouch: an unusual cause of colocolic intussusception

Intussusception involving the colon is unusual in adults and when present is managed with resection due to the risk of malignancy. We present an unusual case where the intussusceptum was impacted stool in a mucosal pouch in the transverse colon. The patient presented with bleeding per rectum and abdominal pain and was found to have a colocolic intussusception on computed tomography. Colonoscopy showed an ulcerated mass in the transverse colon. A laparoscopic right hemicolectomy was performed. Histopathology demonstrated known chronic lymphocytic leukemia, but not solid malignancy. A large fecalith impacted within a mucosal pouch had acted as the lead point. This represents a highly unusual but benign cause of intussusception.

Appendiceal Fecalith Presenting as a Submucosal Cecal Polyp Removed During Colonoscopy

Appendiceal fecaliths, also known as stercoliths or coproliths, are rigid masses comprised of fecal material that become lodged within the appendix. They are generally accepted to be a primary etiologic agent of acute appendicitis and appendiceal intussusception in adults. We report a case of an asymptomatic woman undergoing colonoscopy found to have a submucosal appearing mass below the appendiceal orifice. A neoplastic appearing lesion on the orifice of the appendix was resected, after which a fecalith extruded into the colonic lumen. This is the first reported case of appendiceal fecalith discovered and completely removed during colonoscopy in an asymptomatic patient.

Appendicitis with submucosal fecalith mimicking a submucosal tumor: a case report

Background

Submucosal fecalith(s) mimicking submucosal tumors of the gastrointestinal lumen are rare. Moreover, accurate preoperative diagnosis of these entities is exceedingly difficult, and the mechanism(s) of their formation remains unclear.

Case presentation

A 40-year-old woman visited the authors’ hospital due to lower abdominal pain and diarrhea. She had previously been treated for endometriosis. Laboratory investigation revealed increased C-reactive protein levels. Abdominal contrast-enhanced computed tomography revealed thickening of the appendix wall and dilation of the small intestine. The patient was diagnosed with paralytic ileus caused by appendicitis, and interval appendectomy was scheduled. She underwent laparoscopic-assisted appendectomy after conservative treatment. Partial cecal resection was selected due to the presence of an elastic mass in the cecum. The final pathological diagnosis was submucosal fecalith, not submucosal tumor. On day 5, the patient was discharged without any postoperative complications.

Conclusions

In cases of appendicitis with fecalith(s) that appear as submucosal tumor(s) on colonoscopy, submucosal fecalith mimicking submucosal tumor should be considered in the differential diagnosis.

Reactive lymphoid hyperplasia with a lipomatous component associated with fecal compaction in an appendiceal orifice

A 69-year-old man underwent endoscopic mucosal resection of a solitary polyp located in the cecum. After the procedure, a fecal mass and appendiceal orifice appeared under the cut surface. A diagnosis of reactive lymphoid hyperplasia was made based on the results of an immunostaining analysis, which revealed a segregated population of T cells and B cells in multiple lymphoid follicles. The aggregation of adipocytes forming a lipomatous area and granulation tissue was also observed. We speculate that the compaction of the fecal mass in the appendix triggered mucosal inflammation, resulting in the formation of the polyp, which concealed both the feces and appendiceal orifice.