pneumatosis intestinalis ( pi ) is a rare and unexpected disorder defined as accumulation of gas in the submucosa or subserosa of the large or small intestine .
it is associated with a variety of diseases , and its pathogenesis is still obscure .
, it has been reported in 12 cases after pediatric orthotopic lt [ 1 - 5 ] , although nearly none has been reported in adult liver recipients .
we report three cases of adult liver transplant recipients in whom the diagnosis of pi was made by computer tomography ( ct ) and simple x - ray ( table 1 ) .
the patients in case 1 and 2 were unremarkable during post - operative period , and they were discharged home . the patient in case 1 experienced high fever and watery diarrhea after two months and the patient in case 2 complained of watery diarrhea after four months . the patient in case 3 experienced high fever and watery diarrhea one month after the transplantation without discharge . at admission ,
all patients were stable in blood pressure , pulse rate , and respiratory rate , but in case 1 and 3 , patients had high body temperature ( 38.8 and 38.5 ) .
the physical examination showed severely distended , non - tender abdomen , with hypoactive bowel sound and tympanic percussion in case 1 .
the laboratory findings of all cases did not reveal abnormal findings except mildly elevated c - reactive protein , ranging 0.38 to 1.59 mg / dl ( normal range , < 0.3 mg / dl ) .
serial blood tests of case 1 were positive twice for cytomegalovirus ( cmv ) antigenemia , but other cases showed all negative results .
the peak titer of cmv antigenemia was 10/400,000 and colonoscopic finding did not show abnormal finding in case 1 .
the cytotoxicity assay of the all patient 's stool was negative for clostridium difficile toxin .
stool cultures and special stains for micro - organisms were all negative in all patients .
abdomen simple x - rays and ct in abdomen revealed diffuse pneumatosis intestinalis of the colon , ileus , and free air under diaphragm , but no air in the portal vein in case 1 and 2 ( fig .
1 ) . an abdominal ct of case 3 demonstrated pneumopericardium , diffuse linear pneumatosis intestinalis of the colon and extraluminal air within retroperitoneum and mesentery but no free intraperitoneal air ( figs . 2 , 3 ) .
all patients were conservatively managed with bowel rest , parenteral nutritional support , intravenous antibiotics ( cefotaxime , ampicillin / sulbactam , and metronidazole ) because of no signs of peritonitis .
the patients in case 1 was treated with additional antiviral agent ( ganciclovir ) for positive cmv antigenemia and nasogastric tube decompression for free air , but other patients did not receive antiviral agent and did not have nasogastric tube decompression .
the patients in case 1 and 3 did not receive immunosuppressive agent for 1 week , but the patient in case 2 received reduced immunosuppressive treatment with fk506 ( 2 mg daily ) , methylprednisolone ( 2 mg daily ) , and mycophenolate mofetil ( 500 mg daily ) .
he remained in excellent general condition from the admission and had a sense of well - being during hospitalization .
the abdominal distension of case 1 resolved and diarrhea improved within a week and antibiotics were discontinued .
all patients were given a diet , and were discharged home after the pi resolved clinically and radiographically .
the common factor linking pi to organ transplant recipients is steroid treatment . in this report
, one patient did not receive steroid treatment and the other two had steroid treatment but the amount was only 4 mg / day .
drug concentrations of fk506 and mycophenolate mofetil ( mmf ) in all patients have low levels as well .
it might be possible that immunosuppression including fk506 , steroid , and mmf did not cause of pi in our cases .
symptoms that have been attributed to pi are in decreasing order of frequency : diarrhea , bloody stool , abdominal pain , abdominal distension , constipation , weight loss , and tenesmus . in this report , three recipients had watery diarrhea , and two had high fever . the physical examination of recipients did not show specific findings except abdominal distension in one case .
the patients did not have abdominal pain , tenderness , rebound tenderness , and rigidity of abdominal wall .
there was no clear evidence of peritonitis despite of pneumoperitoneum and air density in mesentery and retroperitoneum in simple x - rays and ct scan of abdomen .
we assumed that there was no direct communication between lumen and peritoneum , therefore conservative treatment should be performed rather than surgical exploration .
however , patients with white blood cells of more than 12,000/mm with or without the symptoms of clinical obstruction such as emesis , vomiting , and pain , age over 60 years were considered to be candidates for surgical intervention . based on this report
, pi should be considered as the differential diagnosis of adult after lt who suffers from watery diarrhea and fever .
pneumoperitoneum , air - density in mesentery and retroperitoneum in patients with pneumatosis intestinalis without signs of peritonitis improved with conservative management .
 pneumatosis intestinalis is an uncommon disorder characterized by an accumulation of gas in the bowel wall . 
 we described three cases undertaking liver transplantation . 
 the patients developed diarrhea in three cases and high fever in two . an abdominal x - ray and computed tomography scan demonstrated extensive pneumatosis intestinalis in the colon with pneumoperitoneum mimicking hollow organ perforation . 
 however , the patients had no abdominal symptoms and there was no evidence of peritonitis . 
 the infection work - up was negative except one case with cytomegalovirus antigenemia . 
 after one week of conservative management including bowel rest and antibiotic therapy , their pneumoperitoneum resolved spontaneously without any complication . 
 pneumatosis intestinalis should be considered as a differential diagnosis after adult liver transplantation with patients suffering from watery diarrhea and fever . 
 pneumoperitoneum , air - density in mesentery and retroperitoneum in patients with pneumatosis intestinalis without signs of peritonitis improved with conservative management , which included bowel rest and antibiotic therapy . 
INTRODUCTION
CASE REPORT
DISCUSSION