topic presentation on hydatid disease

1. Hydatid Disease
-BISHAL SAPKOTA
-INTERN,GMCTHRC

2. Hydatid Cyst of Liver
Introduction
 Hydatid disease is a worldwide zoonosis produced by the larval stage of the
Echinococcus tapeworm .
 The two main types of hydatid disease are caused by
E. granulosus and E. multilocularis.
 E. granulosus is commonly seen in the great grazing regions of the world—
particularly the Mediterranean region, Africa, South America, the Middle East, China
& South East Asia
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3. Life cycle of Echinococcus
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4. Hydatid Cyst Structure
 The hydatid cyst has three layers:
(a) the outer pericyst, composed of modified host cells that form a
dense and fibrous protective zone;
(b) the middle laminated membrane, also k/a Ectocyst which is
acellular and allows the passage of nutrients;
(c) the inner germinal layer, also k/a Endocyst where the scolices (the
larval stage of the parasite) and the laminated membrane are produced.
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5.  Daughter vesicles (brood capsules) are small spheres that contain the
protoscolices and are formed from rests of the germinal layer. Before becoming
daughter cysts, these daughter vesicles are attached by a pedicle to the germinal
layer of the mother cyst. At gross examination, the vesicles resemble a bunch of
grapes.

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7. Pathogenesis
 The hydatid cysts are mainly located in the liver as the
liver acts as 1st filter in 60-70% of human infections as
embryos after hatching out penetrates intestinal wall and
enter into radical of portal vein.
 It can also be present in lungs as sometimes the embryo
pass through hepatic capillaries and enter the pulmonary
circulation , lung act as 2nd filter.
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8.  A few embryos may pass through pulmonary circulation too
and enter various organs
 Thus rarely, the cysts may be found in the brain, eye, kidney,
muscles ,bones ,spleen, genital organs.
8
Hydatid cyst
showing a
row of brood
capsules
attached to
the germinal
layer.

9. Clinical Features
 The clinical features are highly variable. The spectrum of
symptoms depends on the following:
 Involved organs
 Size & Site of Cysts
 Interaction between the expanding cysts and adjacent organ
structures( bile ducts & the vascular system of the liver )
 Pressure symptoms usually occur late, except when they occur in the
brain .
 Immunologic reactions such as asthma, anaphylaxis, or
membranous nephropathy secondary to release of antigenic material
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10. Hepatic Disease
 The right lobe is the most frequently involved portion of the
liver.
 Once in the human liver, cysts grow to 1 cm during the first 6
months and 2–3 cm annually thereafter, depending on host
tissue resistance.
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11. Diagnosis
 Radiodiagnosis
 Examination of cyst fluid
 Serodiagnosis
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12. Radiodiagnosis
 Plain X-rays
 pulmonary cysts of E. granulosus - rounded masses of
uniform density.
 But may miss cysts in other organs unless there is cyst wall
calcification (as occurs in the liver).
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13. X ray showing Hydatid
cyst in left lung.
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14. Xray showing Hydatid cysts in liver 14

15. 15MRI, CT, and Ultrasound
reveal well-defined cysts with thick or thin walls.
The most pathognomonic finding- daughter cysts
within the larger cyst.
Eggshell or mural calcification on CT, is indicative of
E. granulosus infection and helps to distinguish the
cyst from carcinomas, bacterial or amebic liver
abscesses, or hemangiomas.

16. CT scan of liver-showing a
Large cyst occupying
most of right lobe. And
daughter cyst (arrow)
attached to germinal
membrane by stalk.
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17. CT scan showing a round lesion
with water attenuation and a
ringlike pattern of calcification
(arrows). This pattern represents
calcification of the pericyst
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18. a)CT scan-Cystic lesion(arrows)
in body and tail of pancreas
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b)CT scan showing Cystic
lesion in spleen and liver
c) Two thick walled cysts in lungs

19. USG Classification (WHO-IWGE, 2003)
 Group 1 : Active group – cysts larger than 2 cm and 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.
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20. 20

21. Examination of cyst fluid
 A specific diagnosis of E. granulosus infection can be
made by the examination of aspirated fluids for
protoscolices or hooklets
 Not usually recommended because of the risk of fluid
leakage resulting in either dissemination of infection or
anaphylactic reactions.
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22. Serodiagnosis
 can be useful, although a negative test does not exclude the
diagnosis.
 Can be carried out by
 ELISA
 RIA(radioimmunoassay)
 Complement fixation
 IHA(indirect haemagglutination)
 Cysts in the liver elicit positive antibody responses in 90% of
cases whereas up to 50% of individuals with cysts in the
lungs are seronegative.
 Detection of antibody to specific echinococcal antigens by
immunoblotting has the highest degree of specificity
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23. Complications
 Rupture
 pain
 anaphylactic reaction
 peritonitis
 If biliary tree involved: cholangitis, obstructive
jaundice, or pancreatitis.
 Into the bronchi : expectoration of cyst fluid, scolices.
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24. 24Infection • Liver abscess
• Mild fever to full blown sepsis
Allergic reactions • Urticaria
• Brochospasm
• Anaphylaxis
• Eosinophilia
Pressure Effects • Obstructive Jaundice
• Budd-Chiari Syndrome
Organ dysfunction • Cholangitis
• Biliary Cirrhosis

25. Management
 Medical Therapy
 Surgical Therapy
 PAIR (Puncture, Aspiration, Injection & Reaspiration)
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26. Medical Therapy
 Indications:
 Patients with primary liver or lung cysts that are inoperable
 Patients with cysts in 2 or more organs, and
 Peritoneal cysts.
 Chemotherapeutic agents:
 Two benzimidazoles are used, albendazole and mebendazole.
 Albendazole is administered in several 1-month oral doses
(10-15 mg/kg/d) separated by 14-day intervals.
 The optimal period of treatment ranges from 3-6 months,
 Mebendazole is also administered for 3-6 months orally in dosages of 40-
50 mg/kg/d.
 Praziquantel 60mg/kg along with albendazole for 2 weeks.
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27. Contraindications to Medical Therapy
 Early pregnancy,
 Bone marrow suppression,
 Chronic hepatic disease,
 Large cysts with the risk of rupture, and
 Inactive or calcified cysts.
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28. PAIR
 Performed using either ultrasound or CT guidance,
 Puncture usually using a 22G needle through thickest portion
 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.
 The cyst is then filled with isotonic sodium chloride solution.
 Perioperative treatment with a albendazole (15mg/kg/d) in 2 divided doses is
mandatory (4 days prior to the procedure and 1-3 months after).
 The cysts larger than 6 cm in diameter should undergo PAIR technique with drain
catheter placed for 24 hrs.
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29. 29
Puncture
Confirmation of diagnosis
aspiration
Injection of
scolicidal agent
Reaspiration

30. Indications
 Inoperable patients
 Patients refusing surgery
 Multiple cysts in segment I, II, and III of the
liver
 Relapse after surgery or chemotherapy
Contraindications
 Early pregnancy,
 Lung cysts,
 Inaccessible cysts,
 Superficially located cysts (risk of spillage),
and
 Cysts communicating with the biliary tree
(risk of sclerosing cholangitis from the
scolecoidal agent).
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31. Surgical Treatment
 Choice of Surgery:
 Radical total or partial pericystectomy with omentoplasty
 Hepatic segmentectomy
 During the operation scolicidal agents are used.
 Nowadays Laparoscopic Approach is being tried.
(Laparoscopic Pericystectomy)
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32. 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 .
 Cysts in lungs, brain, kidneys, eyes, bones .
Contraindications
 General contraindications to surgical
procedures
 Multiple cysts in multiple organs;
 Cysts that are difficult to access;
 Dead cysts;
 Calcified cysts
 Very small cysts
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33. 33

34. Hydatid Cyst removed from Brain 34

35. Conclusion
 Many hydatid cysts remain asymptomatic, even into advanced age.
Parasite load, the site, and the size of the cysts determine the degree of
symptoms.
 The liver is the most common organ involved, followed by the lungs.
These 2 organs account for 90% of cases of echinococcosis.
 Surgery remains the main treatment of the hydatid liver disease , PAIR
technique still promising.
 Patient education about the prevention of this zoonotic infection .
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36. MCQ 36
Q} water lily appearance in a
chest radiograph suggest
a. Metastasis
b. Cavitating metastasis
c. Aspergilloma
d. Ruptured hydatid cyst

37. Q} diagnosis of hydatid disease is by
a. Biopsy
b. X-ray
c. Casoni test
d. Serum examination
Q} during surgical exploration for hydatid cystof
liver any of the follwing except can be used as
scolicidal
a. Hypertonic saline
b. Formalin
c. Cetrimide
d. Povidine iodine

38. References
 Bailey And Love’s Short Practice Of Surgery, 25th Edition
 SRB’s MANUAL OF SURGERY;4E
 Schwart’s Principles Of Surgery;10E
 Surgery Essence;3E; Pritesh Singh
 Bedside Clinicals in Surgery; Makhan lal saha;1E ,2011 reprint
 Internet Sources
 Google
 Webmd.Com
 Radiopedia.Org
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39. ANY QUESTIONS?