Fascioliasis: sonographic abnormalities of the biliary tract and evolution after treatment with triclabendazole

Abstract

SummaryDiagnosis of infection with the liver fluke Fasciola hepatica is usually difficult. Ultrasonography (US) might be a useful diagnostic alternative, and we assessed the value of sequential US in the diagnosis and monitoring of fascioliasis in 76 patients at baseline and for 60 days after treatment with triclabendazole. At baseline, biliary abnormalities were observed in 52 patients. Crescent-shaped parasites were seen in 11 patients; in 2 cases parasites were spontaneously moving and in 4 patients parasites were motionless. Postprandial examination revealed parasites adhering to the gallbladder wall in a further 5 cases. In 3 further cases, gallbladder contents were mobile but did not sediment downwards after patients changed position. Non-specific abnormalities were: impaired gallbladder contractility (n ϭ 23), gallbladder tenderness (n ϭ 19), debris (n ϭ 6), calculi (n ϭ 5), wall thickening (n ϭ 2) and bile duct dilatation (n ϭ 12). During day 1-7, Fasciola-like crescents in the gallbladder or passing through the bile duct were detected in another 15 patients, impaired gallbladder contractility in 16, gallbladder tenderness in 16, and bile duct dilatation in an additional 28 patients. Thirty-two patients with these US abnormalities experienced colic-like abdominal pain accompanied by increased alkaline phosphatase in 25 cases. During day 30-60, abnormalities regressed completely in 45 patients; 2/6 triclabendazole failures were evident by detection of living parasites. Biliary tract abnormalities are frequently observed by US, but the detection-rate of Fasciola hepatica is disappointingly low despite the parasite's relatively large size. US findings must therefore be interpreted together with other clinical measurements. The visualization of parasites being expelled through the dilated common bile duct allowed the causal interpretation of post-therapeutic abdominal pain and increase of liver enzymes. When triclabendazole is given on suspicion, visualization of worm expulsion and bile duct dilatation by US may be used to confirm diagnosis.

The efficacy and tolerability of triclabendazole in Cuban patients with latent and chronic Fasciola hepatica infection.

“…Details on ultrasonographic methodology are published elsewhere. 28 Clinical evaluation and safety assessment. For close monitoring, patients were hospitalized at the Institute of Tropical Medicine 'Pedro Kouri' (IPK) during the first 7 days after treatment in order to allow prompt therapy if adverse events occurred.…”

Population dynamics of intermediate snail hosts of Fasciola hepatica and some environmental factors in San Juan y Martinez municipality, Cuba

“…Both species can host larvae of the trematode, but only the former has been found naturally infected in the island. Currently, only the curative aspect of the disease is taken into account by a chemotherapy treatment of the final host (Ritchter et al 1999, Millan et al 2000. No integrated program aiming at stopping or at limiting the transmission of the parasite, associating the control of intermediate snail hosts to other control strategies is currently carried out at the national level.…”

Efficacy and tolerability of two single-day regimens of triclabendazole for fascioliasis in Peruvian children

“…Third, biliary colic and increased liver enzymes do not occur in individuals treated with TCBZ for other indications such as paragonimiasis (58) . Last, ultrasonographic studies of the liver fl uke have shown that the parasites stop moving on posttreatment day 3, and the whole parasite or its fragments are eliminated through the biliary tract, with a transitory increase in the diameter of the biliary duct (59) (60) .…”