Case Presentation: A 71-year-old male presented to an outside emergency room after the abrupt onset of severe abdominal pain and vomiting. Physical exam revealed fever, hypotension, and a diffusely tender abdomen with guarding. His past medical history was a complicated course of multiple admissions to outside facilities for abdominal pain over the previous six months, during which a colonoscopy demonstrated areas of ischemic bowel. Crohn’s disease was diagnosed clinically, although never confirmed with pathology. The patient was placed on mesalamine and prednisone, but mesalamine was discontinued after four days due to pancytopenia. The patient had been doing well on prednisone for the past two months. Laboratory tests on admission showed severe leucopenia, thrombocytopenia, lactic acidosis, and hyperbilirubinemia. CT of the abdomen and pelvis showed thickening of the distal small bowel wall with large volume pneumoperitoneum and debris in the pelvis consistent with a perforated viscus. Significant splenomegaly was also noted. Bowel perforation due to Crohn’s disease was suspected, and the patient was transferred to our facility via helicopter for emergency laparotomy. There was gross contamination of the abdominal cavity and three distinct areas of small bowel perforation were identified with a large nearly circumferential defect in the mid-portion of the jejunum. The perforated segments were removed and the small bowel was left in discontinuity as the patient was moved to the ICU for continued resuscitation with a negative pressure VAC pack in place. Continued exploration the next day resulted in an ileocecectomy due to a necrotic portion of the terminal ileum. The small bowel was diffusely edematous with palpable discontinuous lesions and areas of mesenteric adenopathy. The remaining segments were anastomosed, an end ileostomy was created, and he was returned to the ICU in critical condition. The pathology report revealed a transmural peripheral T-cell lymphoma (TCL) associated with EBV positive B-cell lymphoproliferative disorder with extensive necrosis and perforation. Multiple resection margins were positive for tumor and extensive necrosis. The patient continued to deteriorate; he expired 8 days later.
Discussion: Although T-cell lymphoma involving the small bowel can result in perforation and peritonitis, this is unusual at presentation and is associated with a very poor prognosis, thus stressing the importance of prompt diagnosis. Differentiating small bowel involvement by TCL from inflammatory bowel disease is a diagnostic challenge as the clinical presentation, as well as colonoscopy and imaging findings, are non-specific and may mimic benign lesions. Due to these ill-defined findings, TCL can easily be misdiagnosed as Crohn’s disease and subsequently treated with immunosuppressive agents. Close endoscopic and CT imaging surveillance may aid in obtaining a diagnosis and determining appropriate treatment, although histologic and immunohistochemical studies are necessary for a definitive final diagnosis. This case emphasizes the importance of including lymphoma in the differential diagnosis due to its aggressive clinical behavior and potentially devastating outcome.
Conclusions: A prompt diagnosis of T-cell lymphoma involving the small bowel is challenging as clinically it may mimic benign inflammatory lesions such as Crohn’s disease. Misdiagnosis with devastating results may ensue if clinicians fail to consider this important aggressive differential.