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the disease often occurs spontaneously , especially in the elder population with underlying atherosclerosis , and is caused by embolic or thrombotic occlusion of colonic vessels or by conditions leading to hypoperfusion of the colonic wall ( nonocclusive form ) .
the typical clinical presentation is sudden onset of left - sided lower abdominal pain often followed by hematochezia within 24 h. in most patients the disease is self - limiting , but the severe form of ischemic colitis , colonic gangrene , is a life - threatening disease usually requiring urgent surgery .
these factors include decreased cardiac output caused by shock , arrhythmias , congestive heart failure , ongoing cardiac bypass operation or aortic repair .
other reasons for colonic ischemia are coagulation disorders such as deficiency of protein c , protein s or antithrombin iii , sickle cell disease , and vasculitis disorders such as systemic lupus erythematosus , polyarteritis nodosa or thromboangiitis obliterans .
various drugs including digitalis , vasoconstrictors , antihypertensive drugs , psychotropic agents , nonsteroidal anti - inflammatory drugs , and antidiarrheal agents have been identified as precipitating factors for colonic ischemia .
antineoplastic drugs such as bevacizumab in combination with irinotecan and 5-fluorouracil   or docetaxel in combination with vinorelbin   may cause ischemic colitis . however , therapy for non hodgkin 's lymphoma with cyclophosphamide , vincristine , doxorubicine , prednisolone and rituximab ( r - chop ) has not been described as a precipitating factor for ischemic colitis .
colitis occurring during antineoplastic chemotherapy is most frequently due to direct toxic effects or severe neutropenia .
both toxic effects on the colonic mucosa and neutropenic enterocolitis should be differentiated from ischemic colitis . here
we report the association of recurrent episodes of colonic ischemia in relation to standard antineoplastic chemotherapy for b - cell lymphomas .
histology taken 200 cm from incisors by double balloon enteroscopy established the diagnosis of jejunal b - cell lymphoma .
systemic antineoplastic therapy containing the monoclonal antibody rituximab 375 mg / m ( day 0 ) , combined with cyclophosphamide 750 mg / m , vincristine 2 mg , doxorubicine 50 mg / m ( each given at day 1 ) and prednisolone 100 mg on days 1 - 5 ( r - chop ) was initiated .
mesna and ondansetron were given for prophylaxis of cyclophosphamide - induced cystitis and emesis , respectively .
two days after the initiation of chemotherapy the patient was admitted to the emergency department because of sudden onset of left - sided lower abdominal pain followed by hematochezia . computed tomography of the abdomen revealed , besides the small bowel lymphoma with lymph node involvement , thickening of the descending and sigmoid colon .
laboratory tests including stool analysis for enteritis pathogens were unremarkable except for an elevation of c - reactive protein to 23.5 mg / l .
colonoscopy showed inflammation with semicircular longitudinal swelling and petechial bleeding in the descending and sigmoid colon ( fig .
histology from the descending colon showed complete necrosis of the superficial epithelium and infiltration of the submucosal layer by polymorphonuclear neutrophilic leucocytes consistent with ischemic colitis .
the second course of chemotherapy containing chop plus rituximab was well tolerated , but 4 days after the third course of chemotherapy , the patient presented again with sudden onset of diffuse abdominal pain .
a new episode of colonic ischemia was diagnosed by a ct scan of the abdomen , which showed nearly complete regression of the lymphoma , but also marked thickening of the entire colon wall .
laboratory tests again showed no neutropenia , but a rise of c - reactive protein to 69.7 mg / l .
in the present case , differential diagnosis was difficult because the patient initially presented with abdominal pain due to jejunal lymphoma .
the first episode of colonic ischemia was thought to occur spontaneously in a heavy smoker , but the occurrence of two clinically typical episodes of ischemic colitis after chemotherapy argues for the association of reduced blood supply of the colon following the application of chemotherapy .
various drugs have been described as possible triggers for the nonocclusive form of ischemic colitis .
however , the patient did not take drugs having a known association with ischemic colitis .
colitis associated with antineoplastic chemotherapy is usually associated with severe neutropenia 7 - 10 days after completion of the course or with a direct toxic effect .
some chemotherapeutic drugs such as bevacizumab in combination with irinotecan and 5-fluorouracil or docetaxel in combination with vinorelbin may cause colon ischemia [ 3 , 4 ] , but chemotherapy according to the r - chop protocol , which is a standard regime for treatment of non hodgkin 's lymphoma , has not been associated with the development of ischemic colitis .
after switching chemotherapy to bendamustine combined with prednisolone and rituximab , no episodes of colon ischemia occurred during the following three cycles .
we therefore favour cyclophosphamide , doxorubicine or vincristine or the combination , respectively , as the cause for the two episodes of colonic ischemia .
as illustrated in this case , clinicians should be aware of possible ischemic colitis in patients with abdominal pain during chemotherapy with the chop regime .
the occurrence of acute ischemic colitis may be associated with the intake of various drugs . 
 however , colitis during antineoplastic chemotherapy usually is due to toxic effects or neutropenia and not caused by ischemia . we describe a 51-year - old man with jejunal b - cell lymphoma who developed recurrent episodes of ischemic colitis following chemotherapy with cyclophosphamide , vincristine , doxorubicine and prednisolone plus rituximab ( r - chop ) . after switching chemotherapy to bendamustin plus 
 rituximab no further episodes of colonic ischemia occurred during the following cycles of chemotherapy . in conclusion , 
 chemotherapy of lymphoma using a standard protocol with chop and rituximab may cause ischemic colitis .