Intestinal And Lung Flukes

Parasitology Intestinal and Lung Flukes February 2008

INTESTINAL FLUKES

Adult in small intestine

FASCIOLOPSIS BUSKI ●

Scientific name

: Fasciolopsis buski

●

Common name

: giant intestinal fluke

●

Disease

: Fasciolopsiasis

●

Geographic Distribution ●

Cyst digested, worm attaches to intestinal mucosa

Found in Central and South China as far north as the Yangtze valley, Taiwan, Thailand, Laos, Vietnam,

Man eats metacercaria on raw water plants

Cambodia, India, Korea, Indonesia ●

Chief

endemic

area

in

Kwangtung

and

Chekiang

provinces of China

Cercaria encysts on water plants, secretes cyst wall; becomes metacercaria man eats metacercaria

MORPHOLOGY ●

Thick, fleshy, ovate, flesh colored

●

Measures 2.0-7.5 cm by 0.8-2.0

●

Cuticle covered with transverse rows of small spines

●

Oral sucker about ¼ the size of the ventral sucker

●

Intestinal tract consists of a short prepharynx, bulbous pharynx, a short esophagus, and a pair of unbranched

●

●

Miracidium in ssnail develops into LIFE CYCLE OF FASCIOLOP SIS BUSKI

sporocysts

redia I

Cercaria breaks out of the redia II and snail into water

redia II

PATHOLOGY AND SYMPTOMATOLOGY

Two dendritic testes lie in tandem of the posterior half

●

Areas of imflammation, ulceration, and abscesses at the site of attachment

Single branched ovary in the middle of the body to the

●

Epigastric pain, nausea, and vomiting

right of the midline

●

In heavy infections: edema, ascitis and anasarca

Vitellaria lateral to the ceca extend from ventral sucker

●

Slight

anemia,

leukocytosis,

often

sometimes

a

leucopenia or lymphocytes

to the posterior end of the body ●

Miracidium frpm egg and penetrates snail

ceca with two characteristics lateral indentations. of the worm ●

Undevelopd eggs passed in feces into freshwater

Convoluted uterus opens in the common genital atrium

●

Complete recovery follows removal of

at the anterior border of the ventral sucker

●

Clinical

manifestations

due

to

the worms

toxic

products

of

the

worm MIRACIDIUM EPIDEMIOLOGY

●

Covered with cilia

●

Has spined head, pigmented eye spot, two flame cells,

●

The natural definitive hosts are humans. hogs and dogs

cephalic glands and germinal cells

●

The

CERCARIAE ●

METACERCARIAE ●

outer friable cyst and firm inner wall

hosts

are

the

planorbis

snails

The second immediate hosts are aquatic vegetation like:

o o o o o o

145 µ

216 by 187µ

immediate

Segmentiba, hippeutis, Gyraulus ●

With slender muscular tails and heavy bodies 195 by

●

first

●

water caltrop (Trapa bicomius) water hyacinth (Eichomia) water chestnut (Eliocharis tuberosa) water bamboo (Zizania) water morning glory (Ipomaea aquatica) lotus (Nymphaea lotus)

Human infection usually results from the ingestion of metacercariae on fresh edible water plants that grow in ponds fertilized by night soil

●

When eaten raw, the pods of the water caltrop and the bulbs of the water chestnut are peeled with their teeth, thus enabling the detavhed metacercariae to enter the digestive tract.

DIAGNOSIS

ian & virns

●

Clinical symptoms in an endemic area

●

Final diagnosis

1 of 6

Parasitology – Intestinal and Lung Flukes o

Page 2 of 6

finding eggs in the feces

●

Egg:

●

●

yellowish ellipsoidal 130-140 µ by 80-85 µ

●

Has clear thin shell with a small operculum at

●

one end Undeveloped when passed into feces

Two ovoid testes side by side in posterior fifth of the body

Eggs resemble those of:

●

Nonprotrusible, nonadhesive genital sucker at the left posterioborder of the ventral sucker

●

●

●

Large ventral sucker in the anterior middle third of the body

●

●

Cuticle covered with fine scalelike spines

Absence of cirrus and cirral sac, the seminal vesicle opening within the genital sucker

Fasciola hepatica except for the distribution of

●

Subglobose ovary anterior to the testes

yolk granules

●

Vitellaria with large polyglonal follicles in the lateral

Gastrodiscoides hominis – narrower and greenish

posterior third if the body

brown ●

o

Echino perfoliatus – smaller

adult flukes sometimes vomited or passed in the Metacercariae excyst in duodenum

feces TREATMENT ●

Praziquantel 25 mg/kg TID

●

Niclosamide 100 mg/kg as single dose

●

Dichlophen 2-3 gm evry 8 hrs for 3 doses

Definitive hosts ingest raw or insufficiently cooked infected fish

PREVENTION ●

Avoid eating raw aquatic plants

●

thorough

cooking

or the steeping

of the plant\s

LIFE CYCLE OF HETERPHYE S HETERPHYE

snail ( 1st IH)

Miracadium develops into sporocyst

Encystation as metacercariae in fish (2nd IH)

CONTROL ●

Treatment of human sources of infection

●

Reduce infestation of water palnts by:

Fresh swimming circarae

treating night soil containing eggs by storage or unslaked lime

o

Mature eggs passed out in feces and reach water

ingested by fresh water

in

boiling

o

Adults in small intestine of humans and fish eating mammals

killing

the

water

with

eggs,

miracidia, and

unslaked

lime

(100

cercariae

in

ppm)

copper

or

radiae 1 or 2 generation

the

sulfate (20ppm) ●

restrain infected hogs from contaminating areas where water plants are growing

● ●

Destroy immediate snail host Education of the public and fundamental changes in eating habits HETEROPHYES HETEROPHYES Scientific name

: Heterophyes heterophyes

PATHOLOGY AND SYMPTOMATOLOGY

●

Common name

: Von Siebold’s fluke

●

No marked symptoms nor appreciable injury too the

●

Disease

: Heterophyiasis

●

Geographic Distribution

●

in heavy infections

●

o

intestine except with heavy infections

Found in Egypt, particularly the Lower Nile valley, Greece,

Israel,

Central

and

South

China,

●

intestinal mucosa

Korea, Taiwan, Philippines o

High incidence of infection near Port Said, Egypt

●

where local fishermen continually pollute the water

●

and a high percentage of mullets are infected

chronic intermittent mucoid diarrhea with colicky pains and abdominal discomfort due to irritation of the

Japan,

presence of eosinophilia but not anemia eggs may cause granulomatoous lesions in the heart and brain when worms Penetrate the intestinal walls and gel into the lymphatics or venules

MORPHOLOGY ●

Pyriform grayish fluke

●

Small size: 1.3-0.5 mm

beriberi and cerebral hemorrhage respectively EPIDEMIOLOGY

cardiac

Parasitology – Intestinal and Lung Flukes ●

The definitive hosts are man, domesticated and wild fish

Page 3 of 6

●

eating mammals ●

The first intermediate hosts are brackish water snails

●

such as Pirenella in Egypt and Cerithidea in Japan ●

The second intermediate host is a fish chiefly Mugit

with

minute

scalelike

Humans acquire thr infection by eating raw fresh mullet

●

more

Large ventral sucker, situates to the right of the midline Two oval testes, obliquely side by side in the posterior Globose ovary at the junction of the middle and lower third of the body

●

DIAGNOSIS

Coarse

vitellaria

in

a

fan

shape

distribution

in

the

posterior lateral fields

By finding the eggs in the feces Eggs: o

Light brown, thick shelled, operculated

o

Measures 29 by 16 µ

o

Contains fully developed miracidia at ovipostion

o

Shell has a slight shoulder at the rim of the

Metacercariae excyst in duodenum

Adults in small intestine of humans and fish eating mammals

operculum and sometimes a knob at the posterior pole

Definitive hosts ingest raw or insufficiently cooked infected fish

It differs from Clonorchis sinensis eggs by: o

their broad ends with indistinct opercular shoulders

o

less developed posterior spine

It differs from Metagonimus yokogawi by: o

light yellow color

o

thin shell

LIFE CYCLE OF METAGONIM US

Encystation as metacercariae in fish (2nd IH)

TREATMENT ●

spines

third of the body

or fessik (salted mullet) pickled for less than 14 days

●

covered

with a genital opening at its anterior rim ●

(mullet) and tilapia in Egypt and Acanthogius in Japan ●

Cuticle

numerpous at the anterior end

Mature eggs passed out in feces and reach water

ingested by fresh water snail ( 1st IH)

Miracadium develops into sporocyst

radiae 1 or 2 generation Fresh swimming circarae

Praziquantel- 20 mg per kg 3x a day for 2 consecutive days

PREVENTION ●

Avoid eating raw or improperly cooked or recently salted fish in endemic areas

●

Sanitary disposal of waste or excreta

CONTROL ●

General measures are impracticable because of: o

impossibility of detecting and treating human carrier

o

presence of animal reservoir hosts

o

difficulty of enforcing sanitary measures METAGONIMUS YOKOGAWI

PATHOLOGY AND SYMPTOMATOLOGY ●

Similar to Heterophyes heterophyes

●

Eggs may enter the lymphatics or mesenteric venules and set up granulomatous lesions in distant foci such as

●

Scientific name

: Metagonimus yokogawi

●

Common name

: Yokogawa’s fluke

the heart and nervous system causing cardiac beriberi

: Metagonimiasis

and cerebral hemorrhage respectively

●

Disease

●

Geographic Distribution o

Most common heterophyid in the FarEast

EPIDEMIOLOGY

o

Has been reported in Japan, China, Korea ,

●

eating mammals

Philippines, Taiwan,m Siberia and Balkans, Greece and Spain

The definitive hosts are man, domesticated and wild fish

●

The first intermediate hosts are sp of the genera Semisulcospira, Thiara and Hua

MORPHOLOGY

●

nd

The 2

intermediate hosts are the fresh water

●

Small size 1.4 by 0.6 mm

salmonoid fishes of the genera Plecoglossus and Salmo

●

Pyriform shape with a rounded posterior and a tapering

and thw cyprinoids of the genera Richardsonian

anterior end

(Leusciscus) and Odontubutis

Parasitology – Intestinal and Lung Flukes ●

Page 4 of 6

Humans and other mammals acquire the infection by eating raw infected fish

●

The waters inhabited by susceptible snails and fish are contaminated by the fecal discharges of humans and other mammals

LABORATORY DIAGNOSIS ●

Identification of the eggs in feces Eggs: o

Light yellow brown, tyhin shelled, operculated, 28 by

o

With nodular thickening on the posterior end

o

Contains a mature miracidia at ovipostion

17 µ

TREATMENT ●

Praziquantel : 20 mg/kg TID for 2 days

PREVENTION ●

Avoid ingestion of inadequately cooked or raw fish

●

Sanitary disposal of waste or excreta

●

Scientific name

: Echinostoma ilocanum

●

Common name

: Garrison’s fluke

●

Disease

: Echinostomiasis

●

Geographic distribution

ECHINOSTOMA ILOCANUM

o

Infection

is

PATHOLOGY AND SYMPTOMATOLOGY ●

:

prevalent

in

Northern

Luzon,

Leyte,

Samar and Mindanao o

It

is

also

found

in

Indonesia,

India,

China

and

●

MORPHOLOGY ●

Reddish gray, 2.5 – 6.5 mm by 1.0 – 1.35 mm

●

Integument covered with plaquelike scales

●

Anterior end provided with a circumoral disk surrounded with a crown of 49 – 51 spines

●

Oral sucker lies at the center of the disk

●

Ventral sucker in the anterior fifth of the body

●

Testes deeply lobed and in tandem

●

Ovary located in front of the testes Uterus between the intestinal ceca bounded by the ventral sucker and ovary

●

Crescent shaped vitelleria in the lateral

In

heavy

infections,

diarrhea

sometimes

bloody,

and

abdominal pain ●

General intoxication may result from absorption of the metabolites of the worm

Thailand

●

Inflammation at the site of attachment of the worm in the intestinal wall

EPIDEMIOLOGY ●

The natural definitive hosts are humans

●

The

first

intermediate

snail

host

are

Gyraulus

convexiusculus and Hippeutis umbilicalis ●

The

second

intermediate

hosts

are

the

snails

Pila

luzonica (“kuhol”) ●

Rats mayserve as an important reservoir host

●

Infection is acquired by ingestion of raw snails that serves as second intermediate hosts of the parasite

LABORATORY DIAGNOSIS ●

Demonstration of eggs in the stools o

fields of the posterior 2/3 of the body

Straw colored, operculated, ovoid, 83 – 116 by 58 – 69 u

o o

LIFE CYCLE

Immature when passed in the feces Morphologically similar to eggs of Fasciola and Fasciolopsis

TREATMENT ●

Hexylresorcinol

●

Tetrachlorethylene

●

Praziquantel

PREVENTION AND CONTROL

Parasitology – Intestinal and Lung Flukes ●

●

Page 5 of 6

In enedemic areas, raw or insufficiently cooked snails

PATHOLOGY AND SYMPTOMATOLOGY

should not be eaten

Four types of lesions produced in the tissues

Drinking water also should be boiled

1)

Nonsuppurative

o

Eggs infiltrated the tissues causing round cell and connective tissue reaction  abscess

LUNG FLUKE 2)

PARAGONIMUS WESTERMANI

Tubercle like lesion Contains caseous material

●

Scientific name

: Paragonimus westermani

●

Common name

: Oriental lung fluke

3)

Suppurative lesions

●

Disease

: Paragonimiasis

4)

Ulcerative

o

: Pulmonary distomiasis

o

Partial healing

: Endemic hemoptysis ●

Organs involved

:

Geographic distribution

Cosmopolitan distribution among mammals

●

o

Presence in humans is chiefly confined in the Far

●

Abdominal cavity – abscess formation common

east

●

Muscular tissue – ulceration most common

Principal endemic regions are in Japan, South Korea,

●

Liver

Thailand, Taiwan, China and the Philippines

●

Intestinal wall

Human

and

●

Mesenteric lymph nodes

South

●

Testes

●

Brain

●

Peritoneum

●

Pleura

o o

infections

Southeast

Asia,

also

reported

Indonesia,

in

islands

South

of

the

Pacific, and northern South America MORPHOLOGY ●

Reddish brown fluke

●

Measures 8 – 16 mm by 4 – 8 mm

●

Active:

resembles

a

spoon

with

Clinical one

contracted ●

●

●

●

Lungs

o

●

Chronic course and insidious onset

●

Most common symptoms are referable to the

of preserved –oval, coffee bean

o

Chest Abdomen

Suckers of equal size, the ventral just

o

anterior to

o

Lymph nodes

the equatorial plane

o

Brain

Irregularly lobed testes, oblique to each other, in posterior third of worm

Chest

Lobed ovary anterior to testes on right side

●

Similar

to

bronchopneumonia

or

opposite closely coiled uterus

pleural effusion

Vitellaria in extreme lateral fields for entire length of

o

Blood streaked sputum

body

o

Frank hemoptysis

o

Persistent and distressing cough

o

Chest pain

LIFE CYCLE

bronchiectasis

with

Abdomen ●

Rigidity and tenderness

Lymph node glandular fever ●

Abscess in the skin over the involved nodes

Brain ●

Jacksonian type of epilepsy

●

Hemiplegia

●

Monoplegia

●

Paresis of varying degrees

●

Visual disturbances

EPIDEMIOLOGY ●

The natural final hosts are humans and a variety of carnivores

like

cats,

dogs,

mongoose, opossums and rats

aquatic

animals,

the

Parasitology – Intestinal and Lung Flukes ●

Page 6 of 6

The first intermediate hosts are operculated snails of the

o

Intradermal

tests with a Paragonimus antigen

genera: o

: Hua, Semisulcospira, Syncera, and

Far east Thiara

●

MORPHOLOGY ●

Large

o

North America

: Pomatiopsis

●

Moderately thick, dark shell

o

South America

: Pomacea

●

Prominent operculum at the broad end

●

Tickened abopercular end

●

Unembryonated at oviposition

●

Paragonimus westermanii ova is larger, has thicker and

The second intermediate hosts are the: o

Fresh water crabs 

Eriocheir,

genera

Potamon,

Sesarma

and

Parethelpusa o

o o

more deeply stained shell and the thickened abopercular

Crayfishes

end lacks the knob so often seen in Diphyllobothrium



Far East –Astacus



North America - Cambarus

latum ova

Man gets the infection by eating uncooked infected

TREATMENT

freshwater crabs and crayfish

●

Praziquantel – 25 mg/kg TID for 3 days

Metacercariae dislodges during food preparation may

●

Corticosteroids – cerebral involvement

contaminate eating and cooking utensils o

Crushed crab juice may be a source of infection in

PREVENTION AND CONTROL

children in Korea

●

Avoid eating raw, freshly pickled, or imperfectly cooked

●

Refrain from drinking unfiltered or unboiled creek water

freshwater crustaceans DIAGNOSIS ●

Clinical – in endemic areas it is based on: o

Pulmonary symptoms

o

Blood tinged sputum

o

Eosinophilia

o

Chest x-ray 

in endemic districts ●

Ring shadowed opacity, 5 to 10 cm, comprising small

contiguous

cavities

that

give

the

appearance of a bunch of grapes DIFFERENTIAL DIAGNOSIS ●

●

Pulmonary o

Bronchopneumonia

o

Bronchiectasis

o

Pulmonary tuberculosis

o

Pleural effusion and other chest disease

Cerebral o

Cysticercosis

o

Hydatid cyst

o

Encephalitis

o

Meningitis

GENERALIZED PARAGONIMIASIS ●

Filariasis bancrofti

●

Myositis

●

Glandular fever

LABORATORY ●

By finding the eggs o

Sputum

o

Feces

o

Aspirated

material

from

abscesses

effusions ●

Adult worm – exploratory operation

●

In ectopic infections o

Complement-fixation

or

pleural

Public education