Parasitic infestations of the biliary tract
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Transcript of Parasitic infestations of the biliary tract
PARASITIC INFESTATIONS OF THE BILIARY TRACT
AmoebiasisHydatidosisAscariasisFascioliasisClonorchiosisOpisthorchiosis
FASCIOLIASISEtiology:
Zoonosis caused by trematode◦Fasciola hepatica◦Fasciola giganticaEpidemiology
F. hepatica – temperate zonesF. gigantica – tropical zones
Now has become global in distribution
Epidemiologic pattern◦Cases imported by migration◦Autochthonous – isolated, sporadic
infection in areas where animal infestation is present
◦Endemic fascioliasis◦Epidemic fascioliasis – in animal
endemic and human endemic areas
Life cycleF. hepatica flukes
are large, flat, brown and leaf shaped
25 -30 mm by 10-15 mm
F. gigantica upto 75 mm
Adult flukes in common and hepatic bile ducts of human or animal
Eggs – oval, yellowish brown; 130x60 microns
Eggs in tepid water miracidia (9 to 14 days)
Miracidia freshwater snails sporozoites and redia (4 to 7 weeks) free swimming cercaria watercress, water lettuce, alfalfa (aquatic plants)
Life cycleConsumption of Aquatic plants
contaminated with metacercaria
excyst in the duodenum migrate through bowel wall and
peritoneal cavity Glisson capsule of liver (after 4
wks) initiate larval, hepatic and
invasive stages of infection
Extrahepatic forms or ectopic infectionsJuvenile larva adult flukes ( 3-5
months)Adult fluke worms produce eggs in 4
months eggs traverse sphincter of Oddi intestine
Flukes live in biliary tracts between 9-13.5 years
Women more affected; more complications
Risk factorsContaminated aquatic plant
consumptionDietary habitsGeographic location
Treatment of contaminated plants with high doses of KMnO₄ which decrease metacercariae viability
CLINICAL FEATURESAcute infection:
◦3-5 months◦Prolonged fever◦Hepatomegaly◦Abdominal pain◦Eosinophilia ◦Acute cholecystitis like syndrome
with significant eosinophilia
Hyperbilirubinemia is absent in acute phase
Anorexia, weight loss, nausea, vomiting, urticaria
Lasts from migration of immature larvae from duodenum to liver and biliary duct
CHRONIC INFECTION 3-6 months after consumption of
metacercariaeSymptoms – biliary obstruction with
colicky pain in RUQ, epigastrium;Extrahepatic cholestatic syndromeElevation of liver enzymesDilated CBD, parasites in GB and
CBD, stones in GB and bile ductHemobilia
Acute eosinophilic cholecystitis – pruritis and intermittent jaundice
chronic granulomatous inflammation
Hepatic fibrosisCholangiocarcinoma
INVESTIGATIONSUSG Abdomen :
◦Acute Focal areas of increased echogenicity Multiple nodular lesions Single, complex mass in liver Mimics malignancy
◦Chronic Less specific Parasites in GB and CBD Thickening of GB and CBD walls Stones in CBD
COMPUTED TOMOGRAPHYMultiple hepatic metastasis like
lesionsChange in position, attenuation,
and shape over timeHepatomegaly Subcapsular hematomaSub capsular Tract like
hypodense lesions
CTStages
◦Early : contrast enhancement of Glisson capsule
◦Intermediate : subcapsular multiple hypodense nodular areas, tortuous, tunnel-like lesions
◦Late stage : necrotic granuloma as a single, non-contrast-enhanced hypodense irregular mass in liver
◦Liver calcification
LAB. DIAGNOSISAcute phase
◦Antibodies against Cathepsin L1 by ELISA
◦Anti-parasitic trial ◦Eosinophilia
Chronic phase◦Visualisation of parsitic egg in stool◦Sedimentation technique to
concentrate the eggs◦Serial stool specimens
SURGERY IN FASCIOLIASISChronic phase – biliary obstruction with
choledocholithiasisIncidentally found in cholecystectomy
specimens and T-tubesERCP – when there is biliary obstructionIn cholangitis – antiparasites,
percutaneous drainage and anti-biotics ( against E. faecalis, E. coli )
Incidental met. Like lesions in D-lap with eosinophilia – consider fascioliasis
CHEMOTHERAPYTriclabendazole
◦Single dose of 10 mg/kg◦Better absorption with fatty meal◦Adverse effect – biliary colic;
antispasmodic to be administered concurrently
◦Other drugs Bithionol dehydroemetine nitazoxanide
CLONORCHIASIS AND OPISTHORCHIASISClonorchiasis
◦Clonorchis sinensis◦Chinese or oriental liver fluke
Opisthorchiasis ◦Opisthorchis viverrini◦Opisthorchis felineusCommonly found in oriental countries
– China, Laos, Thailand, Korea, Japan, Taiwan
Eating raw and uncooked fish
Life cycle
Two intermediate hosts : Fresh water snail & Fish
Human host adult worms eggs in stools water fresh water snail miracidia sporocyst, redia and cercaria in snail freshwater fish metacercariae in muscles of fish metacercarial cyst (acid resistant ) small intestine of human Liver
Metacercariae navigate through ampulla of vater mature into adult worms in bile ducts
Live for 45 years in liver1000-2500 eggs/dayReside in medium to small
intrahepatic bile ducts, extrahepatic ducts, GB and pancreatic duct
CLINICAL FEATURESMostly asymptomatic5%-10% - non specific symptoms
◦Fever◦Rash ◦Malaise◦RUQ pain◦Flatulence ◦Fatigue
Clonorchis sinensis◦Acute : asymptomatic and non-
specific symptoms◦Chronic:
Recurrent cholangitis Cholecystitis Obstructive jaundice Hepatomegaly Cholelithiasis Multiple hepatic tumours Cholangiocarcinoma
Opisthorchis viverrini:◦Acute : 5-10% have non-specific
symptoms◦Chronic:
Hepatomegaly Intrahepatic duct stones Recurrent suppurative cholangitis Cholangiocarcinoma
Opisthorchis felineus:◦Raw, salted and frozen fish
consumption◦Acute
High grade fever Nausea and vomiting Abdominal pain Malaise, arthralgia and lymphadenopathy Eosinophilia with Increased LFT
◦Chronic Liver abscess and suppurative cholangitis
CHOLANGIOCARCINOMA AND FLUKES O. viverrini ( More common ) C. sinensisSecretion of parasite proteins
with mitogenic properties into bile ducts
Ov-GRN-1Inflammation around biliary tree;
epithelial hyperplasia; metaplasia of mucin-producing cells and periductal fibrosis
DIAGNOSISEggs in stool sampleSerology : Ov-CP-1 based ELISA ,
doesn’t distinguish recent or past infection
USG : Intrahepatic duct dilation; increased periductal echogenicity; GB sludge
PCR to detect adult parasite DNA in stool samples
TreatmentPraziquantelO. viverrini – single dose (40-50
mg/kg)C. sinensis – 25 mg/kg three
times at 5 hour intervals in 1 day
BILIARY ASCARIASISAscaris lumbricoidesRoundworm – 20-30 cm in lengthTropical and sub-tropical regionsPoor socioeconomic conditionsSource of infection -Fecal
contamination of soil and farmsSymptoms – when worms enter
biliary tree
Adult worm of A. lumbricoides
Life cycleAdult worm in human intestine Female lay eggs Feces warm moist soil
maturation mature egg human ingestion
Hatch in duodenum larvae penetrate mucosa portal venous blood liver right heart pulm. Capillary bed trachea esophagus Jejunum
PathologyAscaris reach duodenum
◦ Increased load in jejnum◦ Increased intestinal motility
One or two worms enter biliary system via ampulla of vater
Part of worm may remain in intestineCommon in women and pregnant
women (progesterone)Common after cholecystectomy,
sphincterotomy, choledochostomy
Impacted worm sphincter of oddi spasm biliary colic
Suppurative cholangitis cholangiohepatic abscess
Acalculous cholecystitis, empyema, perforation of bile duct
Acute pancreatitisDuctal stricture and stones
( dead worms)
Clinical featuresChildren ; 2-8 yrsAdults in endemic areas – 35 yrs
(mean)Women > menHistory of previous biliary surgeryVomiting of wormsWorms in stools
Sudden severe upper abdominal painRUQ tenderness and guardingLow grade feverJaundice is usually absentComplications
◦Early Acute suppurative cholangitis Hepatic ascariasis Acute pancreatitis
◦Late- calculi and strictures
Diagnosis Stool analysis for ova and dead
wormsLeukocytosis – suppurative
complicationsHyperbilirubinemia –
hepatopancreatic ascariasisElevated liver enzymes in
cholangitisS. amylase elevation
Imaging Abdominal radiographs – worms can
be seenUSG – dilated bile ducts containing
linear or round areas of increased echogenicity;GB sludge, movement of worms in biliary system; alternating echogenic and echolucent strips
CT is less sensitiveEndoscopy – worm in duodenum;
protruding from ampulla of water
MRCP – useful in pancreaticobiliary ascariasis
ERCP – diagnostic and therapeutic
EUSPTC – in cases of failed ERCP
ManagementConservativeEndoscopic extractionSurgical intervention
ConservativeSpontaneous return to duodenum
in 98% of childrenParenteral analgesics and
antispasmodics – relax sphincterNGAIV fluidsPiperazine citrate through
nasobiliary catheter
Oral anti-helminthics:◦Albendazole 400 mg/day for 1 day◦Mebendazole 100 mg BD for 3 days
and◦Pyrantel palmoate 11mg/kg single
dose
Endoscopic interventionsERCP with sphinterotomy and removal of
wormsExtracted from papillary opening using
dormia basketEndoscopic papillary balloon dilatationRequires multiple sessionsIndications:
◦Severe persistent pain unresponsive to antihelminthics
◦Symptoms or USG abnormalities persist 2 wks after conservative line
◦ Increasing jaundice
SurgicalPTC – in failed ERCP with cholangitisIndications of surgery
◦Intrahepatic duct worms, stones, strictures and abscess
◦Gall bladder ascariasis◦Procedure:
Longitudinal choledochotomy Lap. Cholecystectomy with CBD exploration Choledochoscopy T-tube intra and post-operatively