Experimental Clonorchiasis in Dogs: CT Findings before and after Treatment

Abstract

Disease activity in experimental canine clonorchiasis can be assessed with dynamic CT.

Imaging diagnosis of clonorchiasis

“…In contrast to sonography showing an increased echogenicity of the ductal wall, CT failed to show thickening of the bile duct wall (Choi et al, 1989). A recent experimental study, however, suggested that an active infection could be differentiated from cured clonorchiasis by using the periductal enhancement with the thickened bile duct walls on dynamic contrast-enhanced CT (Lee et al, 2003). The contrastenhanced CT visualized a characteristic finding, transient hepatic attenuation differences (THAD).…”

“…3B). They also asserted that some adult worms were demonstrated on their thin-section CT scans (Lee et al, 2003). MR imaging has been used in diagnosis of various diseases of the biliary system, and MR cholangiography is a relatively new non-invasive imaging modality for evaluation of the biliary pathology.…”

Clonorchiasis and Cholangiocarcinoma: Etiologic Relationship and Imaging Diagnosis

“…The national survey in Korea in 1997 revealed that the prevalence of clonorchiasis was still 1.4% (77a). The difficulty of eliminating clonorchiasis in areas of endemic infection has been attributed mainly to the difficulty in detecting infected cases, although other contributory factors, including reinfection after treatment, have been discussed (37,64). C. sinensis is currently the most prevalent human parasitic helminth detected by fecal examination in Korea (52,76).…”

“…The low sensitivity was attributed to false-negative cases with mild infection, and the low specificity was attributed to false-positive cases with residual pathology after cure. This low specificity is of particular interest, since the number of cases cured has been continuously increasing over recent decades due to nationwide control and changes in the ecological environment (38,64). Ultrasonography is less useful in the differentiation between cured clonorchiasis and active infection, since it reflects the pathological changes in the bile ducts (73), which may persist for years after cure (15,37,65), rather than reflecting the presence of the worm itself.…”

“…These findings are considered pathognomonic for clonorchiasis (11,12,14,70). Computed tomography was previously thought to be of little value in delineating the fluke itself (12,70); however, a recent experimental study (64) revealed that the fluke can be visualized by thin-section helical computed tomography. This study also demonstrated that disease activity can be assessed by dynamic contrast-enhanced computed tomography during experimental canine clonorchiasis, suggesting the possibility of distinction between active clonorchiasis and cured cases with residual pathology.…”