Immune-related intestinal pseudo-obstruction caused by immune checkpoint inhibitors: case report

Abstract

Intestinal obstruction, a rare manifestation of immunotherapy-related gastrointestinal adverse events, can be severe and even life-threatening with intestinal perforation. We present a 64-year-old man with HCC and currently under the therapy with Pembrolizumab, who was admitted in our hospital with abdominal distension. Radiologic findings were consistent with small bowel ileus. After conservative treatment, the patient underwent colonoscopy where no cause of ileus was discovered. The patient received high-dose prednisone due to the side effects of immune checkpoint inhibitor therapy. This resulted in a gradual improvement of symptoms.

Keywords: adverse effects; bloating; constipation; immune checkpoint inhibitor; immune-related pseudo-obstruction.

Figure 1

Clinical images of hepatocellular carcinoma in a 64-year-old man. (A) Advanced CT imaging has detected a significant mass in the right hepatic lobe, spanning multiple segments with dimensions of 112 mm x 77 mm x 83 mm. (B) Advanced CT imaging has identified a tumor in the right lobe of the liver with dimensions of 75 mm by 67 mm by 67 mm. Following completion of TACE, the efficacy of the treatment is PR in accordance mRECIST. (C) MRI revealed the largest hepatic tumor measuring approximately 69 mm x 63 mm x 67 mm. The efficacy of the radiotherapy has been evaluated as PR.

Figure 2

Timeline of the clinical course. TACE, transcatheter arterial chemoembolization; iv.gtt., intravenous drip; po., per os.

Figure 3

Clinical images during the treatment. (A) Plain abdominal x-ray shows no evidence of bowel distension or free intraperitoneal gas, but revealed increased colonic content and mild dilatation at the hepatic flexure of the right colon, along with gas-fluid levels. (B) Gastroscopy demonstrated features of chronic non-atrophic gastritis, with congested and edematous gastric folds, multiple ulcerative scars in the antrum, and flaky congestion in the duodenal papilla. (C) Pathological examination confirmed mild chronic mucosal inflammation with interstitial vascular congestion and a minor eosinophilic infiltrate. (D) Colonoscopy revealed congestion and edema of the colorectal mucosa, indistinct vascular patterns, friable mucosa prone to contact bleeding, and superficial erosions and ulcerations, leading to a diagnosis of colitis. (E) The pathology indicates a moderate level of chronic inflammation in the mucosa, with the presence of cryptitis and crypt abscesses. (F) Abdominal and pelvic scans revealed colonic dilation with fluid and gas accumulation.

Figure 4

GI irAEs Management Flowchart.