Case No. :	25
Month :	January
Year :	2001
Contributor :	Dr. Mansi Awasthi

Case report |Radiological Findings | Discussion

Case report:

A seventeen- year- old girl presented with acute pain in abdomen. She had a history of high-grade fever without chills, intermittent pain in abdomen and malaise since fifteen days. On examination she was febrile with a distended, tender abdomen with guarding. A Widal test which had been done four days previously was positive for Salmonella typhii. She had been started on appropriate antibiotic treatment.

Ultrasonography at that time had revealed an anechoic collection in the gall bladder fossa. This was in continuity with a distended gall bladder. The gall bladder walls were irregular and the medial wall appeared to be floating in the collection. An ultrasound guided needle aspiration of the collection revealed bile. A diagnosis of gall bladder perforation was made.

Radiological Findings:

A CT scan of the abdomen (Fig 1,2) done at our institution showed a hypodense collection in the gall bladder fossa measuring 9x12x13 cms. The gall bladder wall was thickened and non-enhancing. The collection was seen to be in communication with the distended gall bladder by a centimeter wide defect on its lateral wall and produced an impression on the stomach. There was moderate free fluid with mesenteric stranding. Bilateral basal pleural effusion effusions were present. The liver, spleen and pancreas were normal. A HIDA 99m scan was also performed which clearly demonstrated the biliary leak from the gall bladder. A diagnosis of gall bladder perforation was made. In view of the history of typhoid infection the etiology was postulated to be typhoid induced acalulous cholecystitis. The patient underwent laparotomy and the finding of gall bladder perforation was confirmed. A cholecystectomy was performed and the patient made an uneventful recovery.

Discussion:

Perforation of the gall bladder can be fatal making rapid diagnosis and treatment essential. The common causes are traumatic rupture, calculous and acalculous cholecystitis. Gall bladder perforation following calculous cholecystitis may be associated with trauma. It may lead to free intraperitoneal cholelithiasis, which can be seen on a plain abdominal radiograph. Salmonella typhii is well known to affect the gall bladder and cause acalculous cholecystitis. A large distended gall bladder may then perforate spontaneously as seen in our patient. Gall bladder injuries occur in 2-3% of patients following trauma. However, isolated rupture of the gall bladder without other visceral injury following abdominal trauma is rare.

Gall bladder perforation has been classified as acute [typeI], subacute [typeII] and chronic [typeIII]. Patients presenting with type I perforation may not have any symptoms of gall bladder disease. However, most patients presenting with chronic perforation are symptomatic. Alcohol intoxication has also been implicated as a contributory factor for gall bladder perforation. Alcohol causes gall bladder distension and increases the risk of perforation.

Diagnostic peritoneal lavage in gall bladder perforation yields bile with or without blood. The presence of bile indicates biliary tract injury and is not specific for gall bladder perforation. In isolated traumatic gall bladder rupture the use of diagnostic paracentesis has been reported to be misleading. Hence, preoperative diagnosis on imaging is vital. Ultrasonography, CT and HIDA 99m scan can be used in a case of gall bladder perforation.

The features of non- traumatic gall bladder perforation on USG are free fluid and fluid collections close to the gall bladder fossa, thickened gall bladder wall- 7mm (range 3-20 mm) and localized collection in the gall bladder wall. However, there is no specific sonographic sign of imminent perforation and sonography. In a traumatic perforation there maybe echogenic, non-shadowing, mobile material in the gall bladder associated with free fluid or localized collection in the gall bladder fossa.

CT scan shows free fluid and localized perihepatic and gall bladder fossa collections. The gall bladder can be accurately identified and the site of perforation is often demonstrated. The gall bladder wall is thickened in chronic cases. In posttraumatic rupture, the gall bladder contour is often irregular and high-density hemorrhage maybe seen within the gall bladder lumen and outside its walls (7). Contrast in the duodenum should not be confused with hemorrhage. The exact extent of fluid collections and other visceral injuries are also demonstrated.

HIDA scans can usually demonstrate biliary leakage and is diagnostic.

In conclusion, gall bladder perforation is a condition, which needs prompt diagnosis and treatment. It is usually unsuspected clinically and the diagnosis should be kept in mind while imaging patients of acute abdomen and trauma.