Xanthogranulomatous cholecystitis is a chronic cholecystitis entity characterized by an inflammatory process that destroys the gallbladder. Its exact incidence is little known and is estimated according to studies between 0.2% and 13% [1,2]. His clinic is non-specific. Its macroscopic appearance and radiological presentation can simulate gallbladder cancer, thus complicating diagnosis and management [3,4]. Knowledge of this benign pathology is important in order to make a correct diagnosis to avoid aggressive surgery but also to minimize the complications it will cause. Through this work, we highlight the diagnostic problems posed by xanthogranulomatous cholecystitis, and we review the literature on the radiological aspects of this rare disease in adults.
This is a 64-year-old woman with no particular history, who was admitted to the emergency room for abdominal pain evolving for 2 months with accentuation 1 week ago, accompanied by vomiting without transit disorder. Clinical examination found tenderness in the defenseless right hypochondrium or a palpable mass. Biology showed C-reactive protein at 26.5 mg/L, gamma-GT at 67 IU/L and leukocytes at 11150/mm3. Transaminases, lipase and alkaline phosphatase were normal.
Ultrasound showed a slightly distended, lithiasic, wall-thickened gallbladder with well-limited hypoechoic nodular areas (Figure 1), a continuous linear hypoechoic area (Figure 2) and a common bile duct at 8 mm without bile duct dilation intrahepatic, or effusion especially in the vesicular bed.
CT scan after contrast showed regular lobulated thickening of the gallbladder wall, site of intramural nodules and hypodense mucous bands with enhancement of the luminal surface (Figures 3, 4). This was associated with a calculus of the gallbladder neck and a dilation of the common bile duct to 7.5 mm (Figure 5) without dilation of the intrahepatic bile ducts.
The patient was operated on through the right subcostal approach. The surgical procedure consisted initially in taking a sample by puncture of the gallbladder and then in a second step in performing a retrograde cholecystectomy. Histology finds a thickened fibrous wall whose coating is more or less often ulcerated and a chorion seat of polymorphous and diffuse inflammatory infiltrate; confirming the diagnosis of xanthogranulomatous cholecystitis without detectable signs of malignancy.
Xanthogranulomatous cholecystitis is a rare form of chronic cholecystitis, characterized by a destructive inflammatory process of the gallbladder. It mainly occurs in middle-aged and elderly subjects . Its pathophysiology is still poorly understood, but could result from the association of acute inflammation of the gallbladder and obstruction of the flow of bile by gallstones, leading to extravasation of the latter in the wall leading to an accumulation of histiocytes and the development of micro-abscesses which will later be replaced by xanthogranulomatous nodules [5-7].
The positive diagnosis of xanthogranulomatous cholecystitis is based on histology, however knowledge of the diagnosis preoperatively allows good therapeutic management [3,6]. The clinical expression of xanthogranulomatous cholecystitis is nonspecific and similar to that of acute and chronic cholecystitis . The most reported symptoms are non-specific abdominal pain, nausea, vomiting, a positive Murphy and the presence of a mass in the right hypochondrium .
Imaging has its place in the diagnostic process. Its bet whatever the modalities, is to link gallbladder anomalies to xanthogranulomatous cholecystitis and to eliminate the cancer in order to allow appropriate therapeutic management . Imaging findings are variable, but the most characteristic are diffuse or focal parietal thickening and the presence of stones [4,5]. The detection of intramural nodules or bands is a decisive semiological element [3,5].
Ultrasound is the first-line examination for any symptom suggestive of gallbladder pathology; It makes it possible to detect abnormalities of the gallbladder and to study its environment. Ultrasound findings more often show diffuse thickening of the gallbladder wall with intramural nodules that behave as well-defined hypoechoic nodular areas and intraparietal mucosal bands that are linear hypoechoic patches that may be caused by more involvement generalized mucosa [3,4]. The alignment of these multiple nodules arranged parallel in the gallbladder wall produces a palisade presentation considered characteristic of xanthogranulomatous cholecystitis . L' ultrasound also shows the presence of stones or biliary sludge, which suggests for some authors an additional causal role in this pathology. In addition, complications such as abscess and hepatic infiltration can be observed on ultrasound [3,4,8].
Computed tomography (CT) allows locoregional and remote study. It provides better information on vesicular parietal thickening, which is more often diffuse and generally symmetrical, although rare cases report the association of diffuse asymmetric thickening with xanthogranulomatous cholecystitis [3,9]. She appreciates the intra-mural nodules which are hypo-attenuating and occupy a large part of the thickened wall. This feature has been described as having significant specificity for xanthogranulomatous cholecystitis. On computed tomography, the intraparietal mucosa most often appears continuous (intact) or only with a focal breach . However, CT shows portal phase enhancement of the luminal surface, Magnetic Resonance Imaging (MRI) has better diagnostic performance than ultrasound and CT in this type of pathology, with a sensitivity of around 86% and a specificity of 94.7% according to the studies. In conventional MRI, the vesicular parietal thickening presents as T1 hypo or isosignal and is enhanced late after the injection. The mucosal line within the parietal thickening is continuous and enhances during the dynamic enhancement study. Intramural nodules are less well seen when they are small, unlike CT scans, and the intensity of the signal can vary according to their components; But the presence of intra-nodular or intra-parietal fat is a discriminating semiological element .
Nowadays, diffusion-weighted MRI has shown an advantage in differentiating xanthogranulomatous cholecystitis from wall thickening in gallbladder cancer. In a recent study, Kang et al. observed a lower frequency of diffusion restriction in xanthogranulomatous cholecystitis (7%) than in gallbladder cancer (68%). They also found that the ADC values of xanthogranulomatous cholecystitis were higher than those of wall-thickened gallbladder cancer, with mean values of 1.637 × 10-3 millimeter2/s and 1.076 × 10-3 millimeter2/s, respectively. with p= 0.005 ; Which has not been revealed in other reports to our knowledge.
The treatment consists of performing a total cholecystectomy by laparoscopy, after an intraoperative frozen examination which must be performed because of the high incidence of gallbladder carcinoma accompanying xanthogranulomatous cholecystitis . However, the risks of conversion and complications such as a priori biliary fistulas, a bilioma or a bilioperitoneum are possible [5,10].
Xanthogranulomatous cholecystitis is a destructive inflammatory disease of the gallbladder whose clinical, macroscopic and radiological presentation can simulate a tumor lesion. It is the prerogative of the elderly and middle-aged subject. It constitutes a diagnostic difficulty. Knowledge of the radiological characteristics is an essential contribution to guide the diagnosis and orient the therapeutic management. Histology is the confirmatory examination.
Declaration of interest : The authors declare that they have no conflicts of interest in relation to this article.