Presentation for seminar MBBS

1. HYDATID DISEASE OF LIVER
Roll no 0954

2. History
 Hydatid disease is one of the oldest diseases known to
man. It was first described in the Talmud as a
"Bladder full of water" .
 Hippocrates described the human hydatid disease
more than two thousand years ago with a very
interesting expression (liver filled with water) .

3.  Al-Rahzes wrote detailed script on hydatid cyst of
the liver about one thousand years ago .
 17th century- Francisco Redi illustrated that the
hydatid cysts of echinococcosis were of “animal”
origin
Early to mid 1900s, the more distinct features of E.
granulosus and E. multilocularis
1928- The exact life cycle of the parasite was
recognized by Dew et al.

4. Hydatid : Greek for ‘drop of water’
Echinococcus :
 ‘hedgehog berry’
 coined by Rudolphi in the first decade of the 19th century

5.  Echinococcosis / hydatid disease is a parasitic
disease that affects both humans and other mammals,
such as sheep, dogs, rodents and horses.
 Echinococcus granulosus-
cystic echinococcosis/ unilocular echinococcosis, dog tapeworm
 Echinococcus multilocularis-
alveolar echinococcosis /alveolar colloid of the liver/ alveolar
hydatid disease/ alveolococcosis/ multilocular echinococcosis,
“small fox tapeworm”
 Echinococcus vogeli-
polycystic echinococcosis/ human polycystic hydatid disease/
neotropical echinococcosis
 Echinococcus oligarthus-
polycystic disease rarely.

6. Epidemiology
 E. granulosus is present virtually worldwide, more
common in sheep and cattle raising countries.
 South America, North Africa, Eastern Australia, Asia
and sporadically in the Middle East, Mongolia,
Eastern Europe and the UK.
 India- AP, Gujarat, Tamil Nadu, West Bengal, Orissa,
Bihar, Punjab, Haryana, HP, UP, Kashmir, Delhi and
Pondicherry.
 E. multilocularis -Northern hemisphere, including
central Europe and the northern parts of Europe, Asia,
and North America.
 E. vogeli and E. oligarthus -Central and South
America.

7.  (< 1 case per 1 million inhabitants) in the continental
United States.
 CE in endemic areas ranges from 1-220 cases per
100,000 inhabitants,
Sex
 No sexual predilection.
Age
 The cysts grow slowly ( 1-3 cm / year), and rarely
diagnosed during childhood or adolescence unless the
brain is affected.
 CE is a disease of younger adults, with an average age
at diagnosis of 30-40 years.
 AE is a disease of older adults, with an average age at
diagnosis of older than 50 years.

8. Morphology
Adult worm: 3-6 mm
 Scolex- pyriform 300 µm, 4 suckers and a
protrusible rostellum with two circular rows of
hooklets
 Neck- short, thick
 Strobila- 3 segments usually (immature, mature
and gravid)

10.  32-36 µm length, 25-
32 µm breadth
 Hexacanth
embryo/oncosphere
with 3 pairs of
hooklets.
 Passed through the
faeces of the definitive
host and it is the
ingestion leads to
infection in the
intermediate host.
Egg:

12.  Larva: within hydatid cyst

13. Hosts
Definitive hosts
 E. granulosus: dogs and other canidae
E. multilocularis: foxes, dogs, other canidae and
cats
E. vogeli: bush dogs and dogs
E. oligarthus: wild felids
Intermediate Hosts
 E. granulosus: sheep, goats, swine and other wild
herbivores
E. multilocularis: small rodents
E. vogeli: rodents
E. oligarthus: small rodents
Humans- dead end

14. Life cycle

17. Incubation period
 Months to years or even decades.
 Largely depends on the location of the
cyst in the body and how fast the cyst
is growing.

18. Pathogenicity
 Hydatid cyst represents larval form
 Generally acquired during childhood.
 Gradual displacement of vital host tissue, vessels or parts of
organs → damage and dysfunction
 The cyst wall is formed by:
Pericyst-
 fibrous tissue laid down by host fibroblasts and new blood
vessels.
 merges with surrounding normal tissue.
 Nutrition derived through this layer.
 In old cysts, it may become sclerosed or calcified and
parasite may die within it.
 Absent in lung, bone, muscle, sometimes brain

20. Ectocyst:
 Secreted by embryo
 Tough, acellular, laminated ,elastic hyaline membrane,
1 mm
 Resembles white of a hard boiled egg
 When excise or ruptured, it curls on itself exposing the
inner layer
 Non- infective
Endocyst:
 Germinal layer, 22-25 µm thick
 Consists of number of nuclei embedded in a
protoplasmic mass.
 Gives rise to ectocyst, brood capsules and scolices
 Secretes hydatid fluid.

22. Echinococcus multilocularis-
 Multilocular cysts
 Cyst spreads from the outset by actual invasion
rather than expansion.
 May be mistaken for malignant tumour.
 Destruction of parenchyma may cause hepatic
failure.
 Spread by extension, lymphatic or hematogenous
 Among the most lethal of helminthic infections
 If untreated, 70% progress to death

23. Hydatid fluid
 Clear, colourless or pale yellow.
 Specific gravity= 1.005-1.010
 Slightly acidic, pH 6.7
 Contains sodium chloride, sodium phosphate
and sodium and calcium salts of succinic acid.
 Antigenic, used for Casoni’s test
 Anaphylactic shock on absorption
 Centrifuged deposit shows hydatid sand –
brood capsules, free scolices and hooklets.

25. Organs affected
The parasite can colonise virtually every organ in the body
 Liver- 52-77% (¾ right liver)
 Lung- 8.5-44%
 Abdominal cavity- 8%
 Kidney- 7%
 Central nervous system- 0.2-2.4%
 Bone- 1-2.5%
 Less common- spleen,
bladder, thyroid, prostate , heart, eye, adrenal gland, cervix,
fallopian tube, ovaries, breast, pancreas, subcutaneous tissues.

26. Clinical features
History :
•of living in or visiting an endemic area must be
established.
•Exposure to the parasite through the ingestion of foods
or water contaminated by the feces of a definitive host
must be determined.
•Contact with infected dogs

27.  disease may be asymptomatic (75%) and
discovered coincidentally at post mortem or
when an ultrasound or CT scan is done for some
other condition.
 Most symptomatic cysts ≥ 5 cm
 Depends on site, size, parasite load
 Symptomatic disease presents with a swelling
causing pressure effects.

28.  Dull pain from stretching of the liver capsule.
 Palpable or visible abdominal mass.
 Chronic abdominal discomfort
 Dyspepsia
 Low grade fever
 Obstructive jaundice : Daughter cysts pass through
cytobiliary communication
 Biliary rupture- jaundice, urticaria, biliary colic
 Nausea
 Vomiting
 Cough
 Hydatid emesia
 Hydatid enterica

30. Lungs:
 chronic cough
 dyspnea
 pleuritic chest pain
 hemoptysis.
Cerebral involvement:
 headache
 dizziness
 decreased level of
consciousness
 neurologic deficits

31. Presentations in emergency
 severe abdominal pain following minor trauma
(CT scan may be diagnostic).
 Allergic reactions
 skin rash
 anaphylactic shock if cyst ruptures
spontaneously, from trauma or surgery.

32. Examination
Skin
o Jaundice
o urticaria and erythema
o spider angiomas -portal hypertension secondary to either
biliary cirrhosis or obstruction of the inferior vena cava.
Vital signs
 Fever -secondary infection or allergic reaction.
 Hypotension-with anaphylaxis secondary to a cyst leak
Abdomen
 Abdominal tenderness.
 Hepatomegaly or mass
 Ascites is rare.
 Splenomegaly -splenic echinococcosis or portal
hypertension.

33.  Hydatid thrill
 Camellotte sign
Lungs:
 Decreased breath sounds over the affected area -airway
obstruction with consolidation
Extremities
 Bone -tenderness, palpable mass.
 Muscle - palpable mass.

34. Differential diagnosis
 simple (bile duct) cyst
 benign adenoma
 focal nodular hyperplasia
 metastatic lesion
 biliary cystadenoma or cystadenocarcinoma
 primary hepatoma
 pyogenic or amoebic abscess

35. Investigations
There should be a high index of suspicion.
1.Routine hematology –
 Elevated total leucocyte count
 eosinophilia.
2. Casoni’s intradermal test –
 Low sensitivity(75%) and specificity
 risk of anaphylactic reaction
 considered obsolete now.

36. o Indirect haemagglutination test (IHA)
o Latex agglutination test (LT)
o Immunoelectrophoresis (IEP)
o Double diffusion test (DD)
o Enzyme linked immunosorbent assay (ELISA)
o Radioallergosorbent test (RAST)
o Complement fixation test (CFT)
o Bentonite flocculation test (BFT)
o Indirect fluorescent antibody test(IFAT)
o Counterimmune electrophoresis (CIE)
o Basophil degranulation test (BDT)
3. Immunological serology-
primary tests

37. • Initial screening -highly sensitive test like IHA or LT
• Confirmation - highly specific test like IEP, DD test,
ELISA or RAST.
• Positive IEP test is highly specific for active infection
(cross-reaction with Taenia solium cysticercosis only).
• ELISA and RAST are simple to perform and useful for
population surveys.
• The only serological test that has a role in monitoring
progress after surgical treatment of hydatids is CFT
because it reverts to negative within 12 months of cure.

38. 4. Secondary laboratory
tests Immunoblotting
 Polymerase chain reaction
 Detection of precipitation line- arc 5
•More specific
•Useful in extra hepatic hydatid disease
•Calcified non-fertile liver hydatid

39. Imaging studies
5. Plain X-ray abdomen,
chest:
 an elevated right hemdiaphragm.
 Calcification

40. 6. Ultrasonography
(USG)•easy availability, affordability and diagnostic sensitivity
•Reveals rosettes of daughter cysts
•Double contoured membrane of cyst due to detachment
of cyst membranes
•calcification of cyst wall
Role:
a. Screening in endemic areas and in family members.
b. First line diagnostics.
c. Interventional non-operative procedures.
d. Monitoring treatment and during follow-up.
e. IOUS (Intra-operative ultrasound): useful for localization and
management of small, nonpalpable or deep-seated cysts.

41. CLASSIFICATION OF HYDATID CYSTS
 based on ultrasonographic findings.
Gharbi Classification of Hydatid Cysts
Type I - pure fluid collection - univesicular cyst
Type II - fluid collection with a split wall - detached
laminated membrane - ‘water lily’ sign
Type III - fluid collection with septa - daughter cysts
Type IV - heterogenous appearance - presence of
matrix
- mimics a solid mass
Type V - reflecting thick walls - calcifications
Gharbi Classification of Hydatid Cysts
Type I Pure fluid collection
Type II Fluid collection with a split wall
Type III Fluid collection with septa
Type IV Heterogenous appearance
Type V Reflecting thick walls

42. Classification
 In 2003, the WHO Informal Working Group on
Echinococcosis (WHO-IWGE) proposed a standardized
ultrasound classification based on the status of activity of the
cyst.
 Universally accepted
 Helps to decide on the appropriate management.
Group 1: Active group – cysts larger than 2 cm and often fertile.
Group 2: Transition group – cysts starting to degenerate and
entering a transitional stage because of host resistance or
treatment, but may contain viable protoscolices.
Group 3: Inactive group – degenerated, partially or totally
calcified cysts; unlikely to contain viable protoscolices.

43. WHO classification
• Active
• unilocular
• no cyst wall
• early stage
• not fertile
CL

44. CE1
 Active
 Unilocular, simple cyst
with uniform anechoic
content.
 May exhibit fine echoes
due to shifting of brood
capsules i.e. hydatid sand
(“snow flake sign”).
 fertile

45. CE2
 Active
 Multivesicular,
multiseptated cysts
 Cyst septations produce
“wheel-like” structures
 Daughter cysts indicated
by rosette-like or
honeycomb-like structures.
 Daughter cysts may partly
or completely fill the
unilocular mother cyst.

46. CE3
 Transitional
 Unilocular cyst which may
contain daughter cysts.
 Anechoic content with
detachment of laminated
membrane from the cyst
wall
 floating membrane or
“water-lily sign” -wavy
membranes floating on top
of remaining cyst fluid.

47. CE4
 Inactive
 Heterogenous hypoechoic
or hyperechoic
degenerative contents.
 No daughter cysts.
 Ball of wool sign -
degenerating
membranes.

48. CE5
 Inactive
 Thick calcified wall
that is arch shaped,
producing a cone
shaped shadow.
 Not fertile

49. 7. Computerised
tomography (CT): best imaging modality
 maximum information of the position and extent of
intra-abdominal hydatid disease
 volume of cyst can be estimated
 More accurate to identify cyst characteristics-cart
wheel like- multivesicular rosette like.
 Diagnostic feature is a space-occupying lesion with a
smooth outline with septa.

50. Computerised tomographic (CT) scan showing a hydatid cyst with septa in
the left lobe of the liver.

51. Typical unilocular hydatid cyst. Unenhanced CT scan shows a large hydatid
cyst with a noncalcified, high-attenuation wall in the right hepatic lobe
(arrows).

52. Computerised tomographic (CT) scan of the upper abdomen showing a
hypodense lesion of the left lobe of the liver; the periphery of the lesion
shows a double edge.This is the lamellar membrane of the hydatid cyst
that separated after trivial injury

53. 8. Magnetic resonance
imaging (MRI) / MRCP: When there is jaundice to visualise biliary tree and its
relation to hydatid cyst
 Cystobiliary communication
 Biliary hydatids in bile duct and hepatic ducts
 Much costlier.
• For non-invasive visualization of the pancreato-
biliary complex.

54. Magneticresonancecholangiopancreatography(MRCP)showingalargehepatic
hydatidcystwithdaughtercystscommunicatingwiththecommonbileductcausing
obstructionanddilatationoftheentirebiliarytree

55. 9. Endoscopic retrograde
cholangiography (ERCP)
 Diagnostic and therapeutic role- with sphincterotomy in cases of
biliary rupture of hydatid cyst.
 To find biliary communications.
 Can be used to drain biliary tree before surgery
10. Liver function tests :ALT , AST, GGT, ALP
may be raised
11.Angiography
 lack of specificity
 invasive
 differential diagnosis of suspected malignancy or vascular
malformation.
12. Radionuclide scan :most accurate demonstration
of bronchobiliary fistula.

56. Complications
Rupture
 Internal- into the cyst
 External- cyst bursts into surrounding structures
Minor leaks : increased pain , mild allergic reaction
characterized by flushing and urticaria.
Major rupture: full-blown anaphylactic reaction, peritonitis
Into the biliary tree : cholangitis, obstructive
jaundice, or pancreatitis.
Into the bronchi :expectoration of cyst fluid, scolices.

57. Infection •liver abscesses
•Mild fever to full blown sepsis
Allergic reactions •Urticaria
•Brochospasm
•Anaphylaxis
•Eosinophilia
Pressure Effects •Obstructive Jaundice
• Budd-Chiari Syndrome
Organ dysfunction •Cholangitis
• Biliary Cirrhosis
Spread, recurrence
(8.5-25%)
• Spontaneous Rupture of Cyst
• Iatrogenic Puncture, Surgical Inoculation

58. Treatment
 No need of treatment in asymptomatic and inactive cysts– monitor
size by ultrasound.
 Whether treated medically or in combination with surgery depends
on →Number of cysts, size , anatomical position. co-morbid
conditions
Medical treatment
Indications:
 Single uncomplicated cyst, < 4 cm
 Surgically unfit patients
 Recurrent cysts
 Widely disseminated hydatid disease.
 Localized disease with poor surgical risk.
 Ruptured cysts.
 Significant intraoperative spillage

59. Mebendazole: 40-50 mg /kg/day , plasma ≥74 ng/ml.
Albendazole: 10-15 mg/kg/day (400 mg BD for 4 weeks,
cycle repeated 3 times separated by 2 weeks intervals)
Site: colchicine-sensitive site of tubulin→ inhibits
polymerization → impaired uptake of glucose
Both active against germinal membrane
Praziquantel: 40 mg/kg/day in 2 divided doses.
Once a week as adjunct to albendazole
More active against protoscoleces..

60.  Disease reassessed and decision taken
either for surgery or continue
chemotherapy( 1-year course).
 Post-operatively: 2 weeks praziquantel +
albendazole for material possibly spilled

61. Surgery
 Cystotomy, deroofing and
omentoplasty
 Partial cystectomy
 Partial resection
 Marsupialisation and tube
drainage or omentoplasty
 Radical surgical resection(total
cystopericystectomy)
 Partial hepatectomy, hepatic
segmentectomy
Minimal invasive Open surgery
PAIR
Laparoscopic
cystotomy, deroofing
and omentoplasty
Children- deroofing + tube drainage, capitonnage, omentoplasty and
pericystectomy

62. Principles of hydatid surgery
1) Total removal of all infective components of
the cysts
2) 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

63. Scolicidal agents used during surgery
 Silver nitrate 0.5%
 Hypertonic saline (15–20%)
 Ethanol (75–95%)
 Povidone iodine 10%
 Chlorhexidine 0.5%
 Hydrogen peroxide 3%
 Formaldehyde not used
They may cause sclerosing cholangitis if biliary radicles
are in communication with the cyst wall.

64. PAIR: percutaneous therapy by puncture,
aspiration, injection and reaspiration
 Relatively recent and minimally invasive
therapeutic option, that complements or
replaces surgery
 For uncomplicated liver cysts
 Done after adequate drug treatment with
albendazole (praziquantel)- pre-operative: 3
months

65. Indications for PAIR
Patients with:
• Non-echoic lesion ≥ 5 cm in diameter
• Cysts with daughter cysts (CE2), and/or with detachment
of membranes (CE3)
• Multiple cysts if accessible to puncture
• Infected cysts
• 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

66. Contraindications to PAIR
 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

67.  Done under US/CT guidance
 Under local anaesthesia cyst is punctured using a
cholangiography 22 gauge needle through thickest part
of wall
 Parasitological examination (if possible) or fast test for
antigen detection in cyst fluid is carried out.
 10-15 cc of cystic fluid is aspirated.
 Cyst fluid is tested for bilirubin.
If bilirubin is present: stop the procedure.
If no bilirubin is present: aspirate all cystic fluid.
 95% ethanol solution or hypertonic saline 15-20%
 (1/3 of the amount of aspirated fluid) is injected.
 Reaspiration of protoscolicide solution after 5 minutes.
Technique

69. 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
 Reduced hospitalization time
 Cost of the puncture and chemotherapy usually
less than that of surgery or chemotherapy alone

70. Complications of PAIR
 Urticaria
 Anaphylaxis
 Subcapsular haematoma
 Fever
 Biliary fistula
 Secondary infection of cyst cavity
 Hypotension/ hypotensive shock

71. Surgery
 Preoperative steroids may be used.
 Incisions- midline or right subcostal
 Abdomen is completely explored, liver mobilised
and cyst exposed
 Peritoneal cavity is packed with coloured mops
(To identify pearly white scolices, prevent
spillage)
 Cyst is aspirated through a closed-suction system
 Scolicidal agents are injected into cyst cavity
 Hypertonic saline should be left within cavity for
15-20 minutes to have effect, others- 5 min
 Cyst is unroofed

72. After entering in the abdominal cavity with middle incision, the large right
lobe hydatid cyst is identified.

73. The hydatid cyst is unroofed and evacuated by aspiration. Remaining
daughter cysts are removed after repetitive infusions of hypertonic saline
solutions and chlorexidine

74. Conservative technique
 Evacuation of the cyst contents and leaving the
pericyst.
 The residual pericyst is managed by:
i. marsupialization, which consists of suturing the
edges of opened pericyst with the skin
ii. capitonnage- spiral suturing of the bottom of
cavity upward from base of cavity to edge of cyst
wall
iii. partial pericystectomy
iv. omentoplasty (omentum is thought of fill residual
cavity, to assist healing of raw surfaces and to
promoted resorption of serosal fluid and
macrophagic migration of septic focus)
v. suture closure of the pericyst cavity after filling it
with saline.

75. Placement of the sutures in the lateral anterior edge of the cystic wall
remnant.Then the interior edge is sutured and anchored in the posterior
wall.

76. The capitonnage is completed when the edges of the anterior cystic wall
remnants are sutured in the posterior wall. The capitonage prevents the
postoperative "dead" space, which facilitates the fluid collection.

77. In the previous cavity of the cyst, under the capitonage, drainage is placed.
The penrose drainage will be removed the 2nd postoperative day.

78. Open cyst
evacuation-
aspiration, removal
of daughter cysts,
resection of active
cyst lining, packing
with omentum
,

79. Indications for external drainage
 Infected cyst
 Biliary communication not found
 Hemorrhagic cyst
 Primary closure not possible
 Omentoplasty not possible

80. Radical surgical procedures
 Cystectomy
 Pericystectomy
 Hepatic resections:
• Segmental
• hemihepatectomy
Complications
•Biliary leakage
Risk factors: purulent and/or bilious
contents, Male, preoperative  alkaline
phosphatase and gamma-glutamyl
transferase
•Biliary fistula
•Infection of residual cavity
•Cholangitis

81. AARONS HYDATID CONE
 To reduce spillage and consequent
secondary implantation
 Cryogenic cone (1971)- adhered by
freezing
damaged tissues and structures, and
an unreliable seal.
 In 1983 Barrie Aarons, surgeon at
Hamilton (Vic.) Australia, perfected
a cone which adhered to the surface
of the liver by suction.
 Set of 2 cones: first having conical
part vertically above suction base,
other with conical part tilted to 20◦ to
vertical

82. •Area of cyst wall >cone base is exposed,
•Cone of best fit is placed in position → suction applied to
obtain seal.
•Hydatid fluid wells into the cone →removed by a separate
wide-bore sucker.
•Cyst cavity is then aspirated, hydatid membrane is removed
•Cavity is sterilized and closed.