2. Hippocrates recognized human hydatid over
2,000 years ago. The Arab physician, Al
Rhazes, made reference to hydatid disease of
the liver in AD 900.
Liver hydatid disease is a zoonosis caused by
caused by larva of the dog tapeworm,
Echinococcus granulosus, with man acting as
an accidental intermediate host.
4. The adult form of Echinococcus granulosus resides in the
small intestine of dogs. The ova from the adult worm are
shed through the canine feces into the environment, where
the intermediate host sheep and humans ingest the eggs, in
humans after entering proximal portion of the small intestine,
the larvae burrow through the mucosa, enter the portal
circulation and travel to liver. The cycle is completed when
dogs eat the carcass of animals infected with the hydatid
5. A primary cyst in the liver is composed of three layers:
1. Adventitia (pseudocyst / pericyst) – consisting of
compressed liver parenchyma and fibrous tissue induced by the
expanding parasitic cyst.
2. Laminated membrane (ectocyst) – is elastic white covering,
easily separable from the adventitia.
3. Germinal epithelium (endocyst) – is a single layer of cells
lining the inner aspects of the cyst and is the only living
component, being responsible for the formation of the other
layers as well as the hydatid fluid and brood capsules within the
cyst. In some primary cysts laminated membranes may
eventually disintegrate and the brood capsules are freed and
grow into daughter cysts. Sometimes the germinal Epithelium
protrudes out towards the external side of the cyst, to form
exogenous daughter cysts, which if left untreated may cause
recurrence.
The Hydatid cysts are slow growing approx. 2 – 3 cm / year and
remain inapparent for long time.
6.
7. Theoretically, echinococcosis can involve any organ.
Organs affected by E granulosus are the liver (63%), lungs (25%),
muscles (5%), bones (3%), kidneys (2%), brain (1%), and spleen
(1%).
The clinical presentation of a hydatid cyst is largely
asymptomatic until complications occur.
The most common presenting symptoms are abdominal pain,
dyspepsia, and vomiting.
The most frequent sign is hepatomegaly/palpable mass.
Jaundice and fever are each present in about 8% of patients.
Bacterial superinfection of a hydatid cyst can occur and present
like a pyogenic abscess.
Rupture of the cyst into the biliary tree.
Free ruptures can result in disseminated echinococcosis and a
potentially fatal anaphylactic reaction.
8. Laboratory Studies
Routine laboratory blood workup: The results of routine
laboratory blood work are nonspecific.
Liver involvement may be reflected in an elevated bilirubin
or alkaline phosphatase level. Leukocytosis may suggest
infection of the cyst. Eosinophilia is present in 25% of all
persons who are infected, while hypogammaglobinemia is
present in 30%.
Serodiagnostic techniques
Indirect hemagglutination test and the enzyme-linked
immunosorbent assay (ELISA) have a sensitivity of 80%
overall (90% in hepatic echinococcosis, 40% in pulmonary
echinococcosis) and are the initial screening tests of
choice.
Immunodiffusion and immunoelectrophoresis demonstrate
antibodies to antigen 5 and provide specific confirmation
of reactivity.
The ELISA test is useful in follow-up to detect recurrence.
9. Plain X-RAY Films:
Findings from plain films of
the chest, abdomen, or any
other involved site are
nonspecific and mostly non
revealing. A thin rim of
calcification delineating a
cyst is suggestive of an
echinococcal cyst.
10. Ultrasound:
currently the primary diagnostic technique and has diagnostic accuracy
of 90%.
Findings usually seen are:
a) Solitary Cyst – anechoic univesicular cyst with well defined borders
and enhancement of back wall echoes in a manner similar to simple or
congenital cysts. Features are suggesting a hydatid etiology include
dependent debris (hydatid sand) moving freely with change in position;
presence of wall calcification or localized thickening in the wall
corresponding to early daughter cysts.
b) Separation of membranes (ultrasonic water lily sign) due to
collapse of germinal layer seen as an undulating linear collection of
echoes.
c) Daughter cysts - probably the most characteristic sign with cysts
within a cyst, producing a cartwheel or honeycomb cyst.
d) Multiple cysts with normal intervening parenchyma (differential
diagnosis are necrotic secondaries, Polycystic liver disease, abscess,
chronic hematoma and biliary cysts.
e) Complications may be evident such as echogenic cyst in infection
or signs of biliary obstruction usually implying a biliary communication.
11. Hydatid cyst of the liver on ultrasound examination. Note the multiloculated
appearance of the cyst due to the presence of multiple daughter cysts.
Detached germinal membranes and brood capsules can be seen in the more
anterior daughter cyst. This multiseptated anechoic or hypoechoic appearance
on sonography is typical of a hydatid cyst.
12. Type I : pure cystic
fluid Collection
(spherical-oval, thick-
walled)
Type II : fluid
Collection with
membrane separation
Type III : Fluid
collection with septa
TypeIV: heterogeneou
s (hypoechoic-
hyperechoic-
intermediate) pattern
Type V: completely
calcified (Reflecting)
walls
13. Has the highest sensitivity of imaging of the
cyst (98%). It is the best mode to detect the
number, size, and location, of the cysts. It
may provide clue to presence of
complications such as infection, and
intrabiliary rupture. CT features include
sharply marginated single or multiple
rounded cysts of fluid density (3 – 30
Hounsfield units) with a thin dense rim.It is
supported by floating membrane within the
cysts on CT scan.
14.
15. Fig. 3.34 Type I, II and III
unruptured hydatid cysts in 4
different patients. (A)
Univesicular uncomplicated
type I cyst in a 54-year-old
man. (B) Multivesicular type II
hydatid with multiple
daughter cysts giving a
septated appearance to the
cyst in a 21-year-old woman.
(C) Old hypermature liver
hydatid in a 64-year-old
man. Non-contrast CT shows
calcification in the cyst wall
and matrix and fluid within
the cyst, suggesting it is still
evolving and not innocuous
and should be treated. (D)
Two hydatid liver cysts in a
75-year-old man. The larger
pseudotumoral cyst has some
calcification in its wall while
the smaller type III cyst is
totally calcified on non-
contrast CT.
16. Angiography – of the liver is suggestive but due to lack of
specificity and availability of lesser invasive techniques it
is rarely required. It may be required in a differential
diagnosis of suspected malignancy or vascular
malformation. Typical features include an avascular lesion
with vascular displacement and a thin peripheral halo of
higher density.
Direct cholangiography – (Endoscopic or percutaneous)
may be required in suspected intrabiliary rupture and bile
duct obstruction. ERCP is also a valuable method for
detecting post-operative complications involving the
biliary tree following surgical intervention.
Radionuclide scan – has largely replaced by ultrasound and
CT scan. It remains most accurate method of
demonstration of a bronchobiliary fistula.
Immunoscintigraphy – is an innovation using radiolabelled
antibodies to antigens in the parasite.
Magnetic resonance Imaging (MRI scan) Images show the
cysts adequately, but MRI offers no real advantage over CT
scan.
17. The treatment of choice is surgery.
Available Options:
Medical
Per-cutaneous
Endoscopic
Surgical
18. CHEMOTHERAPY FOR HYDATID DISEASE OF LIVER
The compounds in common clinical use are
mebendazole and albendazole which inhibit the
uptake of glucose by the parasite and inhibit
production of adenosine triphosphate.
Indications: Chemotherapy is indicated in patients
with primary liver or lung cysts that are inoperable
(because of location or medical condition), patients
with cysts in 2 or more organs, and peritoneal cysts.
Contraindications: Early pregnancy, bone marrow
suppression, chronic hepatic disease, large cysts with
the risk of rupture, and inactive or calcified cysts are
contraindications. A relative contraindication is bone
cysts because of the significantly decreased
response.
19. Mebendazole:Its disadvantages are that it is poorly absorbed from the
gastrointestinal tract. It is no longer used in hydatid disease.
Albendazole
. Albendazole is administered in a dose of 10 – 15 mg/kg/day in adults
or a fixed dose of 400 mg twice daily. The treatment is given in cycles of
28 days with two weeks treatment free periods between the cycles. The
different schedules for the treatment are:
1. Inoperable cases - as primary treatment - 3 cycles
2. Pre-operatively – to reduce the risk of recurrence 6 weeks
continuous treatment
3. Post-operatively to prevent recurrence in cases of intraoperative
cyst spillage – 3 cycles.
Side effects of Albendazole therapy are: mild abdominal pain, nausea,
vomiting, pruritis, dizziness, alopecia, rash and headache. Occasionally
leucopoenia, eosinophillia, icterus, and mild elevation in transaminase
levels.
20. PAIR (Puncture, Aspiration, Injection, Re-
aspiration), was proposed in 1986 by the
Tunisian team that first used it in a prospective
study.
PAIR is a relatively recent and minimally
invasive therapeutic option, that complements
or replaces surgery which was long considered
as the only treatment for CE.
If a catheter is temporarily left in the cyst after
the procedure for drainage (D), the acronym
PAIRD should be preferred.
21. This technique, performed using either ultrasound or
CT guidance, involves aspiration of the contents via
a special cannula, followed by injection of a
scolicidal agent for at least 15 minutes, and then
reaspiration of the cystic contents. This is repeated
until the return is clear. The cyst is then filled with
isotonic sodium chloride solution. Perioperative
treatment with a benzimidazole is mandatory
The cysts should be larger than 5 cm in diameter
and type I or II according to the Gharbi ultrasound
classification of liver cysts PAIR can be performed on
type III cysts as long as it is not a honeycomb cyst.
22. Patients with:
Non-echoic lesion ≥ 5 cm in diameter (TYPE 1)
Cysts with detachment of membranes (TYPE2) and/or with
daughter cysts (TYPE 3),
Multiple cysts if accessible to puncture
Infected cysts
Also
Pregnant women
Children >3 years old
Patients who fail to respond to chemotherapy alone
Patients in whom surgery is contraindicated
Patient who refuse surgery
Patients who relapse after surgery
23. Non-cooperative patients and inaccessible or
risky location of the cyst in the liver.
Cyst in spine, brain and/or heart.
Inactive or calcified lesion.
Cysts communicating with the biliary tree.
Cysts open into the abdominal cavity, bronchi
and urinary tract.
24. Benefits Of PAIR:
Minimal invasiveness
Reduced risk compared with surgery
Confirmation of diagnosis
Removal of large numbers of protoscolices with the aspirated cyst fluid
Improved efficacy of chemotherapy given before and after puncture (probably because
of an increased penetration of antihelminthic drugs into cysts re-filling with hydatid
fluid )
Reduced hospitalization time
Cost of the puncture and chemotherapy usually less than that of surgery or
chemotherapy alone
Risks Of PAIR:
Same risks as any puncture ( haemorrhage, mechanical lesions of other tissues,
infections )
Anaphylactic shock or other allergic reactions
Secondary echinococcosis caused by spillage
Chemical ( sclerosing ) cholangitis if cysts communicate with the biliary tree
Sudden intracystic decompression, thus leading to biliary fistulas
Persistence of satellite daughter cysts
Systemic toxicity of alcohol or hypertonic saline in case of large cysts (total
volume injected must be carefully calculated)
25. Basic Requirements:
Trained personnel
Equipment, Supplies, Drugs (minimum
requirements) :
Ultrasound equipment (portable apparatus) with a 3.5 - 5 MHz probe
Needles (lumbar puncture needles, “fine needles”, especially for multiple
daughter cysts)
Catheters for large cysts (> 5 cm)
95 % alcohol or hypertonic (at least 15 %) saline as protoscolicide agent
“Fast test” for checking the presence of bilirubin in the cystic fluid
Optic microscope
Drugs to be used in case of allergic reactions-anaphylaxis (epinephrine,
hydrocortisone); basic resuscitation equipment
Blood pressure measurement and intravenous catheter must be left in
the forearm during the procedure, so that resuscitation can take place
immediately, should the need arise
26. PAIR Protocol (Minimum
Requirements):
1. Prophylaxis with albendazole
2. Puncture and parasitological examination (if possible) or
fast test for antigen detection in cyst fluid
3. Aspiration of cystic fluid (10-15 cc)
4. Test for bilirubin in cyst fluid
5. If bilirubin present: →→ →→ stop procedure
6. If no bilirubin present: →→ →→ aspirate all cystic fluid
7. Injection of 95 % ethanol solution or hypertonic saline
(1/3 of the amount of aspirated fluid)
8. Re aspiration of protoscolicide solution after 15 minutes
9. New parasitological control if possible
27. • Skin reaction (urticaria [hives], oedema) without arterial blood
pressure (ABP) changes (ABP>115-70 mm HG):
Inject hydrocortisone and/or anti-histamine drug
Careful monitoring of ABP
• Moderate decrease in ABP (115-70>ABP>95-50 mm Hg)
Temporarily stop the procedure
Careful monitoring of ABP
• Marked decrease in ABP (ABP<9O-50 mm Hg)
Stop the procedure
Inject 1/3 mL of epinephrine (1mg/mL) IM or (3mL of a saline
solution of epinephrine-1mL/10mL-through the IV catheter)
Careful monitoring of ABP
• If ABP<95-50:
new injection of epinephrine up to 1mL (IM) or 10mL of the
saline solution of epinephrine (IV)
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
The ERCP is effective in diagnosing biliary tree
involvement from the cyst. The Endoscopic
management is useful in presence of intrabiliary
rupture, which requires exploration and drainage
of the biliary tract and also after surgery in
presence of residual hydatid material
(membranes and daughter cyst) left in biliary
tree. During the endoscopic exploration the
biliary tree is cleared of any hydatid material with
a balloon catheter or a dormia basket. The
endoscopic sphinterotomy is also performed to
facilitate drainage of the common bile duct.
38. Indications: Large liver cysts with multiple daughter
cysts; superficially located single liver cysts that may
rupture (traumatically or spontaneously); liver cysts
with biliary tree communication or pressure effects on
vital organs or structures; infected cysts.
Contraindications: General contraindications to
surgical procedures (eg, extremes of age, pregnancy,
severe preexisting medical conditions); multiple cysts
in multiple organs; cysts that are difficult to access;
dead cysts; calcified cysts; and very small cysts are
contraindications.
39. 1) Total removal of all infective components
of the cysts
2) The avoidance of spillage of cyst contents
at time of surgery
3) Management of communication between
cyst and adjacent structures
4) Management of the residual cavity
5) Minimize risks of operation
All the surgical procedures can be divided
into two large groups, conservative group
and radical group
40. The conservative technique consists of
aspiration of the cyst, instillation of scolicidal
agents and evacuation of the cyst contents
and leaving the pericyst. The residual pericyst
is managed by marsupialization, which
consists of suturing the edges of opened
pericyst with the skin, capitonnage (suture
obliteration), partial pericystectomy,
omentoplasty and suture closure of the
pericyst cavity after filling it with saline.
41.
42. Pericystectomy
Lobectomy
Hepatectomy .
Radical procedures have lower rate of
complications and recurrences but many
authors consider them inappropriate,
claiming that intraoperative risks are too high
for a benign disease.
43. Pericystectomy – This procedure involves non-
anatomical resection of cyst and surrounding
compressed liver tissue. This is technically more
difficult procedure than cystectomy and can be
associated with considerable blood loss; it can
also be hazardous in the case of large and
complicated cysts when the cyst distorts vital
anatomical structures.
Hepatic resections – is the only surgical therapy
for E. multilocularis as the disease is infiltrative
and disease margin is ill defined. The arguments
against hepatic resection as a primary modality
of treatment are that outside of dedicated liver
units there is considerable morbidity and
mortality from resection of what is essentially a
benign condition and also distortion of anatomy
makes surgery more difficult.
44. A special instrument has been developed for the
removal of the hydatid cyst with the laparoscope
called the perforator-grinder-aspirator
apparatus. The instrument penetrates the cyst,
grinds the particulate matter and sucks it all out.
The advantage of this instrument over that of
conventional suction apparatus is that it does not
gets blocked by the daughter cysts and
laminated membranes. Vacuum obliteration of
cavity is carried out with application of – 250
mbar of negative pressure, which obliterates the
cystic cavity by clinging to the opposing cyst
walls.
45. Biliary leakage is the most frequent postoperative
complication following surgery for hydatid cyst of
liver. It has been reported to occur in about 50%
of cases because of the small-undetected
communication between the cyst and the bile
ducts.
The surgical management of hydatid disease of
liver carries a mortality rate of 0.9 to 3.6 % and
recurrence up to 11.3 % within 5 years.
Operations carry a progressively higher mortality
– increasing from 6 % after second to 20% after
third.
46. Chemotherapy: Postoperative treatment with
benzimidazoles is continued for 1 month in patients with
CE who have undergone complete resection or PAIR
successfully. The treatment is continued for 3-6 months
for patients with resected AE, incompletely resected CE,
spillage during surgery or PAIR, and metastatic lesions.
Laboratory tests: Patients on benzimidazoles should have
a CBC count and liver enzyme evaluation performed at
biweekly intervals for 3 months and then every 4 weeks to
monitor for toxicity. ELISA or indirect hemagglutination
tests are usually performed at 3-, 6-, 12-, and 24-month
intervals as screening for recurrence of resected disease or
aggravation of existing disease.
Imaging: Ultrasonography and/or CT scan are used in
follow-up at the same intervals as the laboratory tests or
as clinically indicated.