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Published on: March 17, 2014
A rare case of Pseudomonas aeruginosa enteritis induced by pembrolizumab
Mai Miyamoto1, Shunji Tamagawa1, Masamitsu Kono1
1Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1, Kimiidera, Wakayama-shi, Wakayama, 641-8509, Japan.
Abstract:
A 72-year-old male had pseudomonal enteritis related to pembrolizumab. Chemotherapy for hypopharyngeal carcinoma with lung metastasis comprised cisplatin, 5-FU, and pembrolizumab. On day 14 of chemotherapy treatment he had a sudden prominent abdominal bulge, decreased consciousness, and drop in blood pressure in septic shock. CT scan showed marked intestinal gas through to intrahepatic bile ducts. Pseudomonas aeruginosa was simultaneously detected in both blood and stool cultures. Intestinal endoscopy revealed ulcerative lesions from the transverse colon to the rectum. Pathological investigations indicated apoptosis of the villus. The patient was diagnosed with pseudomonal enteritis induced by immune-related adverse events from the use of pembrolizumab. Treatment by corticosteroid and meropenem were subsequently switched to cefepime and metronidazole, and this successfully improved his colitis. In this new era of biological-targeted drugs and as clinical experience grows, we recommend a high level of alertness for potential diagnosis of infectious complications.
Insights
Pembrolizumab-induced pseudomonal enteritis is a serious risk. This case highlights the need for vigilance regarding infectious complications in patients receiving immunotherapy, especially during chemotherapy.
Area of Science:
- Oncology
- Immunology
- Gastroenterology
Background:
- Chemotherapy regimens for hypopharyngeal carcinoma, including cisplatin, 5-FU, and pembrolizumab, can lead to severe adverse events.
- Immune-related adverse events (irAEs) are increasingly recognized complications of immune checkpoint inhibitors like pembrolizumab.
Observation:
- A 72-year-old male presented with septic shock, abdominal distension, and altered consciousness on day 14 of chemotherapy.
- Imaging revealed intestinal gas extending to intrahepatic bile ducts, and Pseudomonas aeruginosa was isolated from blood and stool.
- Endoscopy showed ulcerative lesions from the transverse colon to the rectum with villus apoptosis.
Findings:
- The patient was diagnosed with pseudomonal enteritis, a rare complication attributed to pembrolizumab-induced immune-related adverse events.
- Initial treatment with corticosteroids and meropenem was followed by cefepime and metronidazole, leading to clinical improvement.
Implications:
- This case underscores the importance of considering infectious complications, particularly pseudomonal enteritis, in patients undergoing immunotherapy.
- Clinicians should maintain a high index of suspicion for irAEs and associated infections in patients receiving novel cancer therapies.
- Early diagnosis and appropriate management are crucial for improving outcomes in patients experiencing severe adverse events from pembrolizumab.
