Puffy Belly
Answer: B
When the clinician detects air in the liver, he must first decide: is this pneumobilia or is this portal venous gas?
Although both conditions include benign and serious etiologies, the distinction must be made upfront, as the
differential diagnosis and management are vastly distinct. Although it is possible to detect either by ultrasound, CT makes the distinction much more readily apparent.
Pneumobilia is air in the biliary tree. It is almost always in a central location within the liver, and is often found in isolated bubbles no more than 5 mm in diameter. Associated air in the gallbladder makes the diagnosis of pneumobilia even more likely. The most common causes of pneumobilia are: post-endoscopic retrograde cholangiopancreatography (ERCP), an incompetent sphincter of Oddi (either post-operative or idiopathic), biliary-enteric fistula (from chronic inflammation or recurrent cholecystitis or symptomatic cholelithiasis), or a surgical biliary-enteric anastomosis (i.e. choledochoduodenostomy, see below).
Portal venous gas is a much more ominous finding; up to 50% of cases are due to mesenteric ischemia (A). Other causes include diverticulitis, small bowel obstruction (C), ulcerative colitis (D), septicemia; a less common
cause is idiopathic (15% of cases, and a diagnosis of exclusion). On CT, portal venous gas follows an extensive
pattern and is not confined to the liver hilum.
An example of portal venous gas:
When the clinician detects air in the liver, he must first decide: is this pneumobilia or is this portal venous gas?
Although both conditions include benign and serious etiologies, the distinction must be made upfront, as the
differential diagnosis and management are vastly distinct. Although it is possible to detect either by ultrasound, CT makes the distinction much more readily apparent.
Pneumobilia is air in the biliary tree. It is almost always in a central location within the liver, and is often found in isolated bubbles no more than 5 mm in diameter. Associated air in the gallbladder makes the diagnosis of pneumobilia even more likely. The most common causes of pneumobilia are: post-endoscopic retrograde cholangiopancreatography (ERCP), an incompetent sphincter of Oddi (either post-operative or idiopathic), biliary-enteric fistula (from chronic inflammation or recurrent cholecystitis or symptomatic cholelithiasis), or a surgical biliary-enteric anastomosis (i.e. choledochoduodenostomy, see below).
Portal venous gas is a much more ominous finding; up to 50% of cases are due to mesenteric ischemia (A). Other causes include diverticulitis, small bowel obstruction (C), ulcerative colitis (D), septicemia; a less common
cause is idiopathic (15% of cases, and a diagnosis of exclusion). On CT, portal venous gas follows an extensive
pattern and is not confined to the liver hilum.
An example of portal venous gas:
Later in the course of the evaluation, our patient became febrile (her blood cultures later grew Klebsiella species). An ERCP showed the patient to have a choledochoduodenostomy and an enlarged papilla obstructed with debris. A balloon papillotomy removed the debris, she responded to antibiotics, defervesced, and fully recovered.
Choledochoduodenostomy has traditionally been used for patients with recurrent common duct stones:
Choledochoduodenostomy has traditionally been used for patients with recurrent common duct stones:
Normally bile is sterile. When a surgical side-by-side anastomosis is created, the gall bladder will be colonized with enteric bacteria that usually do not cause a problem, as long as there continues to be forward flow of gallbladder contents. Once the ampulla is blocked with debris, the gall bladder is “backed up” with infected sludge. Our patient is suffering from sump syndrome (B), the sequela of an infected choledochoduodenostomy.
The more commonly performed approach to recurrent common duct stones is now balloon papillotomy.
Bottom line:
● Having “gall bladder surgery” does not remove the gall bladder or biliary tree from the differential diagnosis
of foregut pain.
● When air is seen in the liver on CT, remember:
● "Tiny Bubbles” in a central location are likely due to pneumobilia, and there is often a recognizable,
treatable condition.
● Something that resembles a super gran explosión de aire is portal venous gas: actively pursue the
diagnosis of mesenteric ischemia.
References
Cameron SL, Sandone C. Gall Bladder and Biliary Tract. In: Atlas of Gastrointestinal Surgery, 2nd Edition, Volume 1, pp 58-60. Johns Hopkins University Press. 2006.
Sherman C, Tran H. Pneumobilia: Benign or Life-threatening. J Emerg Med. 2006; 30(2): 147-153.
Strote SR, Caroon LV, Reardon RF. Identification of Portal Venous Air with Bedside Ultrasound. J Emerg Med. 2012; 43(4): 698–699.
The more commonly performed approach to recurrent common duct stones is now balloon papillotomy.
Bottom line:
● Having “gall bladder surgery” does not remove the gall bladder or biliary tree from the differential diagnosis
of foregut pain.
● When air is seen in the liver on CT, remember:
● "Tiny Bubbles” in a central location are likely due to pneumobilia, and there is often a recognizable,
treatable condition.
● Something that resembles a super gran explosión de aire is portal venous gas: actively pursue the
diagnosis of mesenteric ischemia.
References
Cameron SL, Sandone C. Gall Bladder and Biliary Tract. In: Atlas of Gastrointestinal Surgery, 2nd Edition, Volume 1, pp 58-60. Johns Hopkins University Press. 2006.
Sherman C, Tran H. Pneumobilia: Benign or Life-threatening. J Emerg Med. 2006; 30(2): 147-153.
Strote SR, Caroon LV, Reardon RF. Identification of Portal Venous Air with Bedside Ultrasound. J Emerg Med. 2012; 43(4): 698–699.