Clonorchiasis is a disease caused by the parasitic worm Clonorchis sinensis, primarily affecting the bile ducts of the liver following the consumption of contaminated freshwater fish. It predominantly infects 15 million people in East Asia, with China being the most affected country. Diagnosis typically involves detecting eggs in stool, while treatment options include praziquantel and preventive measures focus on avoiding raw or undercooked fish.

1. Clonorchiasis

2. Outline
Introduction Etiology Epidemiology Pathology
Clinical
features
Diagnosis Treatment Prevention

3. Introduction
● infestation with or disease caused by Clonorchis sinensis
● invades bile ducts of the liver after ingestion in uncooked fish and
when present in large numbers causes severe systemic reactions

4. Etiology
● Clonorchis is a liver fluke parasite (trematode or worm) - Chinese
fluke/Liver fluke
● It was discovered by British physician James McConnell at the
Medical College Hospital in Calcutta (Kolkata) in 1874
● 3 hosts freshwater snail → Fish →mammals
● life span of the Chinese fluke in the host body can reach 40 years

5. Epidemiolo
gy
● 15 million people are infected with C sinensis, predominantly in east
Asia →China, South Korea, northern Vietnam, and parts of Russia
● China has the biggest share with an estimated 13 million people
infected with the parasite
● Clonorchiasis is a major public health problem in South Korea, with an
estimated 1·2 million people infected with C sinensis
● About 1 million people are infected with C sinensis in Vietnam
● 3000 people in the far east of Russia are reported to be infected with C
sinensis
● Clonorchiasis coexists in opisthorchiasis-endemic areas of Thailand
● Male > females
● prevalence increases with age , highest in the 50–59-year age

7. Lu et al. Infectious Diseases of Poverty (2018) 7:28

8. Life cycle (1) Eggs enter the water environment from faeces
(2) eggs are ingested by specific freshwater snails, the first
intermediate host
(3) cercariae released from the snail
(4) cercariae infect specific freshwater fish, the second
intermediate host;
(5) cercariae encyst in the subcutaneous tissues or muscles
of the fish to form metacercariae
(6) metacercariae are ingested by man (and other hosts)
through consumption of raw or undercooked fish, and excyst
as juvenile flukes in the duodenum;
(7) hermaphroditic adult C sinensis predominantly found in
intrahepatic bile ducts

10. Pathogenesis
1
mechanical
obstruction of
the bile ducts by
the worms
2
narrowing of the
bile ducts by
adenomatous
hyperplasia
cause an
obstruction
3
bile stagnation,
and bile pigment
deposition→sto
nes
→cholestasis→
sec bacterial
infection (E.coli)
4
Cholecystitis
→stones in gall
bladder
5
Hepatomegaly
of
predominantly
left lobe , Left
hepatic duct
>>> right
hepatic duct
6
excretory-
secretory
products (ESPs)
→inflammation
and promote
proliferation,
and they
suppress
apoptosis
7
↑ MCM7 protein
:- oncogenesis

11. Clinical
features
● related to worm burden
● With ↓ infection intensity → asymptomatic or mild
symptoms - subfebrility, minor eosinophilia with normal
white blood cell count
● ↑ infection intensity often show unspecific symptoms, such
as itching of the skin, rash asthenia, nausea, indigestion,
headache, dizziness, vertigo, abdominal discomfort,
diarrhoea, or RUQ pain
● Typical physical signs of C sinensis infection are jaundice,
hepatomegaly, and liver tenderness
● Chronic infection results in various complications in the
liver and biliary systems, mainly cholelithiasis (common ),
cholangitis, and cholecystitis
● liver abscess and pancreatitis may occur

12. Clinical fetaures
● Developmental retardation in children with heavy infection
● children often present with inappetence, diarrhoea, malnutrition,
anaemia, and hepatomegaly
● incidence of cholangiocarcinoma 25 per 100000 in female and 35
per 100 000 in male individuals

14. Diagnosis
● the most common is epidemiological anamnesis , ultrasound, CT
● The detection of eggs in stool is the gold standard for diagnosis of C sinensis infection (4 weeks
)
● Eggs may be also detected in bile and gall bladder
● Kato-Katz method is the most widely used technique ,consecutive samples needed
● vegetative resonance testing ???
● Immunodiagnosis for clonorchiasis not sensitive and specific
● Non - specific = Bilirubin, ALT, AST , ALP , eosinophilia

18. TREATME
NT
● Praziquantel is the only recommended
drug for treatment of clonorchiasis
● 25mg/kg praziquantel tid for 1 or 2
consecutive days is usually given, which
can be highly efficacious
● S/E :- dizziness, headache, and
abdominal pain
● Albendazole can be given 10mg/kg for 7
days
● dose of 400 mg tribendimidine achieved
cure rates of 44–50%

19. Preventio
n
● avoiding raw or undercooked freshwater
fish
● Lightly salted, smoked, or pickled fish
can contain infectious parasites
● Cook fish adequately (to an internal
temperature of at least 145° F [~63° C]
● high-endemicity areas , praziquantel (75
mg/kg) was given in selective
chemotherapy twice per year or through
mass drug administration once per year

20. RESOURCE
S
● www. Cdc. com
● Clonorchiasis ,Men-Bao Qian, Jürg
Utzinger, Jennifer Keiser, Xiao-Nong
Zhou
● Korean J. Parasitol. Vol. 45, No. 2: 77-
85, June 2007

21. Thank you