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Paper text:
portal vein gas is an uncommon ominous radiological sign usually harbouring an intra abdominal catastrophe .
we present the case of a 66 years old female presented with acute lower abdominal pain .
general examination revealed tachycardia and pallor . on abdominal examination , there was tenderness and rigidity in the lower abdomen with signs of peritonitis .
blood results included a crp of 242 , wcc 9.3 , mildly elevated urea and creatinine levels , bilirubin 86 and evidence of metabolic acidosis and lactate of 4.2 .
ct scan revealed intestinal pneumatosis affecting the ileal loops , with free gas in the abdominal cavity and gas in the portal venous system , in keeping with acute ischemia and perforation involving ileal bowel loops ( figure 1 and 2 ) ct scan showing portal venous gas and pneumatosis intestinalis in a large intraabdominal cystic mass ( gangrenous meckel s diverticulum ) ct scan showing extensive portal venous gas laparotomy was performed , and it revealed an infracted and severely necrotic large meckel s diverticulum with free fluid in the peritoneal cavity .
she was in a state of multi - organ dysfunction with a low blood pressure despite being on noreadrenaline support .
the liver enzymes were elevated and the platelets count was low with elevated prothrombin time .
there was oliguria with persistent elevation of the urea and creatinine levels , and the patient eventually needed haemofiltration and required assisted ventilation .
unfortunaetly the patient died with septicaemia and multi - organ failure on the fifth postoperative day .
pathology reported a 14 cm small bowel loop with large cystic gangrenous lesion arising from the anti - mesenteric surface measuring 10 cm at maximum diameter .
microscopic examination revealed ulcerated malignant gastrointestinal stromal tumour ( gist ) arising from the orifice of the meckel s diverticulum and protruding within the small bowel mucosa .
portal venous gas is a rare radiological sign . it is usually an ominous sign for an underlying intra - abdominal surgical emergency .
( 1,2 ) the combination of portal venous gas , pneumatosis intestinalis , and acidosis typically portends bowel ischemia and inevitable necrosis .
( 3 ) however , portal venous gas may not predict the severity of the ischemia , which could be reversible . ( 4 ) we present a case of acute abdominal emergency with both radiological signs found on ct .
the operative findings confirmed a well established gangrene in a large cystic swelling arising from the anti - mesenteric border of the ileum about 60 cm from the ileo - ceacal junction .
( 5 ) it is a rare condition with only 275 cases reported in the literature between 1975 and 2008 .
( 2 ) historically , portal venous gas has been associated with high mortality rates and mandatory surgical exploration .
the development of the ct uncovered a wide range of pathologies that do not necessarily warrant surgical intervention .
( 6 ) this is the reason for the claimed recent decrease in mortality rates , but the rates remain high for cases of bowel ischemia .
the case presented , developed multi - organ failure due to the irreversible systemic effect of septicaemia .
the radiologic detection of portal venous gas should not then determine the clinical management of the patient ; rather the disease severity should .
( 7 ) on the other hand , the risk of neoplasm in a meckel s diverticulum is 0.5 - 5% .
leiomyoma is the most frequent tumor , followed by leiomyosarcoma , carcinoid , and fibroma .
gists arising from meckel s diverticulum are extremely rare ; they contribute to 12% of all neoplasm arising in meckel s diverticulum .
histo - pathology for the reported case documented a large meckel s diverticulum of 10 cm in the greatest diameter with hypertrophied ulcerated malignant gastrointestinal stromal tumour ( gist ) at the orifice .
portal vein gas is an uncommon ominous radiological sign usually harbouring an intra abdominal catastrophe . when accompanied by pneumatosis intestinalis , it is more predictive of bowel ischemia . 
 we present a case presented with both signs , who suffered from a rare complication of meckel s diverticulum .