Diagnostic Ultrasound - Abdomen and Pelvis

Xanthogranulomatous Cholecystitis
Diagnoses: Biliary System
TERMINOLOGY
• Uncommon destructive variant of chronic cholecystitis
characterized by lipid-laden inflammation
IMAGING
• US findings
○ Marked GB wall thickening
○ Intramural hypoechoic nodules or bands
– Nodular areas of foamy inflammatory cells or
necrosis/abscess
○ Continuous mucosal line
○ Absence of hepatic invasion
○ Absence of biliary dilation
○ Gallstones
• When infiltrative with involvement of adjacent organs and
surrounding fat/soft tissue obliterating the normal margins,
preoperative differentiation from GB carcinoma nearly
impossible
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Gallbladder carcinoma
• Gangrenous cholecystitis
• Hyperplastic cholecystoses
CLINICAL ISSUES
• Typical symptoms of acute cholecystitis
• Treatment: Open cholecystectomy
• Can coexist with gallbladder carcinoma (adenocarcinoma
seen in up to 10% of resected specimens)
DIAGNOSTIC CHECKLIST
• Difficult to distinguish from GB carcinoma preoperatively
but can be suggested based on imaging findings
• With preoperative awareness and heightened suspicion:
Presence of marked wall thickening and dense fibrous
adhesions should prompt intraoperative frozen section for
diagnosis distinguishing XGC from nonoperable GB
carcinoma
(Left) US in an 83-year-old
woman with RUQ pain,
anorexia, and weight loss
shows multiple shadowing
stones st and diffuse wall
thickening with hypoechoic
intramural nodules ſt and
continuous mucosal line .
(Right) Sagittal MPR in the
same orientation shows
layering stones st and
intramural hypodense nodules
ſt within the markedly
thickened GB wall. (Used with
permission from the American
Institute for Radiologic
Pathology archives, Case ID
#6173.)
(Left) Longitudinal US shows
asymmetric GB wall thickening
with intramural hypoechoic
nodules ſt and a large
shadowing stone in a 43-
year-old woman who
presented with 4-day history
of intermittent RUQ pain.
(Right) CT of the same patient
shows wall thickening and a
large stone with mass
effect on the 2nd portion of
the duodenum st. XGC with
cholecystoduodenal fistula
was confirmed at surgery.
(Used with permission from
the American Institute for
Radiologic Pathology archives,
Case ID #2129.)
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