Not Your Typical Mucocele: A Case Report of a Benign Sigmoidal Diverticular Mucocele.

In recent literature, mucoceles have been discovered to be in the appendix vermiformis or in the nasal sinuses. Although rare, colonic mucoceles, as well as rectal mucoceles, have also been encountered. Furthermore, colonic mucoceles arising from a diverticulum is an even more unusual occurrence, and to date, there has been only one reported case. We present a 48-year-old male with a past medical history of multiple episodes of diverticulitis who presented to the emergency department complaining of bilateral lower quadrant abdominal pain for three days. Upon arrival to the emergency department, the patient had a CT scan of the abdomen and pelvis, which showed an annular constricting 65 mm mass in the proximal sigmoid causing large bowel obstruction. The patient underwent unsuccessful endoscopies and inevitably underwent a hand-assisted laparoscopic sigmoid resection. The following days, the biopsy returned and resulted to be a mucocele arising from a sigmoid diverticulum. We encountered the very first benign colonic mucocele arising from a sigmoid diverticulum.

A Case of Immune Checkpoint Inhibitor Refractory Colitis Treated with Mycophenolate and High-dose Steroids.

Immune checkpoint inhibitors (ICPI) are a class of chemotherapy agents that have emerged as a front-line treatment option for multiple cancers. Nivolumab is an ICPI agent commonly used to treat metastatic melanoma. Although promising, the adverse reaction of this class is broad and per reports, the incidence of colitis is <6%. We present the case of a 71-year-old male with a history of metastatic melanoma who was being treated with nivolumab. The patient was two weeks into his treatment regimen when he began complaining of multiple loose, bloody stools. Because of these symptoms, his nivolumab was discontinued. However, despite discontinuation, his symptoms persisted and the patient underwent a colonoscopy. He was found to have diffuse inflammation of the colon and was diagnosed with nivolumab-induced colitis. Subsequently, the patient underwent multiple treatments, including high-dose steroids, infliximab, and vedolizumab (Entyvio), with no resolution of symptoms. After several months of failed treatment, the patient was readmitted to the hospital for refractory colitis. He was started on high-dose steroids and underwent a repeat colonoscopy, which again showed diffuse colitis. Because of the previously failed treatment options, mycophenolate, an immunosuppressant, was initiated in combination with his steroids. After three days of high-dose steroids and mycophenolate, the patient's symptoms resolved, with no subsequent apparent symptoms of colitis. We present a case of nivolumab-induced colitis, refractory to multiple immunosuppressive medications, which was successfully treated with mycophenolate and high-dose steroids.