This document provides information about hydatid cysts, including: - Hydatid cysts are caused by the larval stage of the Echinococcus parasite and most commonly occur in the liver or lungs. - They have three layers and can expand slowly without symptoms. Symptoms may include abdominal pain or fever. - Diagnosis involves serological tests, ultrasound, CT scan or MRI. Surgical removal is often the treatment of choice along with anti-parasitic drugs. - Surgical techniques aim to inactivate scolices, prevent spillage, eliminate the cyst, and manage any residual cavity. Conservative and radical procedures are described.

1. HYDATID CYST
DR HUSSAIN MUSTAFA
POST GRADUATE
SURGICAL UNIT 5
CIVIL HOSPITAL KARACHI

2. HYDATID CYST:
ECHINOCOCCOSIS (HYDATID DISEASE) IS A
ZOONOSIS CAUSED BY THE LARVAL STAGE OF
ECHINOCOCCUS.
SPECIES: GRANULOSUS , MULTILOCULARIS,
LIGARTUS, VOGELI
IN HUMANS, 50–75% OF THE CYSTS OCCUR IN THE LIVER,
25% ARE LOCATED IN THE LUNGS, AND 5–10%
DISTRIBUTE ALONG THE ARTERIAL SYSTEM. INFECTION
WITH ECHINOCOCCAL ORGANISMS IS THE MOST COMMON
CAUSE OF LIVER CYSTS IN THE WORLD.

3. • DEFINITIVE HOST: DOG
& OTHER CANINE
• INTERMEDIATE HOST:
SHEEP, CATTLE, CAMEL
• HUMAN – ACCIDENTAL
HOST
INFECTIVE STAGE: EGG
(GRAVID PROGLOTTID)
LIFE CYCLE

4. PATHOLOGY
• HYDATID LIVER CYSTS TEND TO
EXPAND SLOWLY AND
WITHOUT SYMPTOMS AND ARE THUS
FREQUENTLY
VERY LARGE ON PRESENTATION.
SINGLE LESIONS ARE
NOTED IN 75% AND ARE
PREDOMINANTLY LOCATED
WITHIN THE RIGHT LOBE (80%). EVEN
THOUGH THE
LESION IS SINGLE, HALF CONTAIN
DAUGHTER CYSTS
AND ARE MULTILOCULAR.

5. THE HYDATID CYST HAS 3 LAYERS:
(A) THE OUTER PERICYST -
COMPOSED OF MODIFIED HOST
CELLS THAT FORM A DENSE AND
FIBROUS PROTECTIVE ZONE;
(B) THE MIDDLE LAMINATED
MEMBRANE - ACELLULAR,ALLOWS
THE PASSAGE OF NUTRIENTS
(C) THE INNER GERMINAL LAYER,
WHERE THE SCOLICES (THE
LARVAL STAGE OF THE PARASITE) AND
THE LAMINATED
MEMBRANE ARE PRODUCED.

6. CLINICAL PRESENTATION
THE CLINICAL FEATURES OF HYDATID LIVER DISEASE
DEPEND ON THE SITE, SIZE, STAGE OF DEVELOPMENT,
WHETHER THE CYST IS ALIVE OR DEAD, AND WHETHER
THE CYST IS INFECTED OR NOT.PAIN IN THE RUQ OR
EPIGASTRIUM IS THE MOST COMMON SYMPTOM,
WHEREAS HEPATOMEGALY AND A PALPABLE MASS ARE
THE MOST COMMON SIGNS.
SYMPTOMS PERCENTAGE
ASYMPTOMATIC 75%
ABDOMINAL PAIN 20%
DYSPEPSIA 13 %
FEVER AND CHILLS 8 %
JAUNDICE 6%

7. INDIRECT HEMAGGLUTINATION TEST AND
ENZYME-LINKED IMMUNOSORBENT ASSAY
ARE THE MOST WIDELY USED METHODS FOR
DETECTION OF ANTI-ECHINOCOCCUS
ANTIBODIES (IMMUNOGLOBULIN G
[IGG]).THESE TESTS GIVE FALSE POSITIVE
RESULTS IN CASES OF SCHISTOSOMIASIS AND
NEMATODE INFESTATIONS THAT IS WHY
THEY ARE NOT SPECIFIC FOR DIAGNOSING
HYDATIDOSIS.
THE INITIAL INTRADERMAL CASONI TEST, THE
HUMAN BASOPHILE DEGRADATION TEST AND THE
COMPLEMENT FIXATION TEST HAVE ONLY HISTORICAL
RELEVANCE
LAB INVESTIGATIONS

8. IMMUNOELECTROPHORESIS : DEPENDS ON
THE FORMATION OF SPECIFIC ARC OF
PRECIPITATION ( CALLED ARC 5 ) WHICH IS
HIGHLY SPECIFIC AND CAN BE USED TO
EXCLUDE CROSS-REACTIONS CAUSED BY
NONCESTODE PARASITES
Eosinophilia - 35%
Bilirubin >2 mg/Dl - 20%
WBC count <10,000/mm3 -10%

9. • IN ENDEMIC AREAS, ELEVATION OF
THE RIGHT HEMIDIAPHRAGM IN
ANOTHERWISE HEALTHY,
ASYMPTOMATIC PATIENT IS HIGHLY
INDICATIVE OF LIVER HYDATIDOSIS
• CLASSIC FINDINGS OF HYDATID CYSTS
ARE CALCIFIED
THICK WALLS, OFTEN WITH DAUGHTER
CYSTS.
RADIOLOGICAL INVESTIGATIONS
CHEST XRAY

10. ULTRASOUND DEFINES THE INTERNAL STRUCTURE, NUMBER, AND LOCATION
OF THE CYSTS AND THE PRESENCE OF COMPLICATIONS. THE SPECIFICITY OF
ULTRASOUND IN HYDATID DISEASE IS AROUND 90%.
ULTRASOUND
BASED ON ULTRASOUND, HASSEN GHARBI IN 1981
CLASSIFIED
LIVER HYDATID CYSTS INTO FIVE TYPES:
TYPE I PURE FLUID COLLECTION.
TYPE II FLUID COLLECTION WITH A SPLIT WALL
(FLOATING MEMBRANE OR WATER LILY SIGN).
TYPE III FLUID COLLECTION WITH SEPTA
(HONEYCOMB IMAGE).
TYPE IV HETEROGENOUS ECHOGRAPHIC
PATTERNS
TYPE V REFLECTING THICK WALLS.

12. COMPUTED TOMOGRAPHY (CT
SCAN)
HIGHEST SENSITIVITY OF IMAGING 98%
CT GIVES SIMILAR INFORMATION TO ULTRASOUND,
MORE SPECIFIC INFORMATION ABOUT THE LOCATION AND
DEPTH OF THE CYST WITHIN THE LIVER.
DAUGHTER CYSTS AND EXOGENOUS CYSTS ARE ALSO
CLEARLY VISUALIZED, AND THE VOLUME OF THE CYST
CAN BE ESTIMATED.
CT IS IMPERATIVE FOR OPERATIVE MANAGEMENT,
ESPECIALLY WHEN A LAPAROSCOPIC APPROACH IS
UTILIZED.

13. MRI AND ERCP
MRI PROVIDES STRUCTURAL DETAILS OF THE
HYDATID CYST, BUT ADDS LITTLE MORE THAN
ULTRASOUND OR CT BUT IS MORE EXPENSIVE.
ENDOSCOPIC RETROGRADE CHOLANGIO
PANCREATOGRAPHY (ERCP) MAY SHOW
COMMUNICATION BETWEEN THE CYSTS AND
BILE
DUCTS AND CAN BE USED TO DRAIN THE
BILIARY TREE
BEFORE SURGERY.

14. TREATMENT
MEDICAL, SURGICAL, AND PERCUTANEOUS APPROACHES
MAY BE PART OF THE TREATMENT.
BASIC PRINCIPLES OF TREATMENT ARE
(1)ERADICATION OF THE PARASITE WITHIN THE CYST,
(2)PROTECTION OF THE HOST AGAINST SPILLAGE OF
SCOLECES
(3)MANAGEMENT OF COMPLICATIONS SUCH AS
PULMONARY INFECTION, CHOLANGITIS, RUPTURE, AND
ANAPHYLAXIS GIVE GOOD REASON TO CONSIDER TREATMENT
FOR ALL.

15. MEDICAL THERAPY
MEDICAL THERAPY FOR ECHINOCOCCOSIS IS LIMITED TO
THE BENZIMIDAZOLES (MEBENDAZOLE AND
ALBENDAZOLE) AND USED ALONE IS ONLY 30%
SUCCESSFUL.
• ALBENDAZOLE IS READILY ABSORBED FROM THE
INTESTINE AND METABOLIZED BY THE LIVER TO AN ACTIVE
FORM.
• MEBENDAZOLE IS POORLY ABSORBED AND IS
INACTIVATED BY THE LIVER.

16. MEBENDAZOLE(3-6 MONTHS ORALLY IN DOSAGES
OF 40-50 MG/KG/D)
ALBENDAZOLE (10-15 MG/KG/D ORALLY 3-6
MONTHS WITH INTERVALS OF 14 DAYS )
PRAZIQUANTEL : MOST ACTIVE AND RAPID SCOLICIDAL
AGENT BUT IT HAS POOR EFFECT ON GERMINAL LAYER
SO IT IS OF CHOICE FOR PROPHYLAXIS IN PRE AND
POST OPERATIVE PERIOD IN ORDER TO PREVENT
SECONDARY IMPLANTATION OF SPILLED
PROTOSCOLECES

17. INDICATIONS:
• PRIMARY LIVER OR LUNG CYSTS THAT
ARE INOPERABLE (BECAUSE OF LOCATION OR
MEDICAL CONDITION)
• PERITONEAL CYSTS OR DEEP CYSTS AND
CYSTS IN BONE BRAIN EYE ETC
• MULTIPLE CYST IN TWO OR MORE ORGANS
• MUTIPLE SMALL CYSTS LESS THAN 4 CM IN
SIZE
• IN COMBINATION WITH SURGERY OR
INTERVENTIONAL PROCEDURE
CONTRAINDICATIONS:
• EARLY PREGNANCY
• BONE MARROW SUPPRESSION
• CHRONIC HEPATIC DISEASE
• LARGE CYSTS MORE THAN 10
CMS WITH THE RISK OF RUPTURE
• INACTIVE OR CALCIFIED CYSTS

18. MINIMALLY INVASIVE TECHNIQUE
PAIR TECHNIQUE
PUNCTURE,ASPIRATION,INJECTION,RE
ASPIRATION
THE MOST FREQUENTLY UTILIZED PROTOSCOLECIDAL
AGENTS
1. 15–20% SALINE,
2. 95% ETHANOL,
3. MEBENDAZOLE
4. 3% H2O2
5. BETADINE
6. SILVER NITRATE
7. FORMALIN
PAIR IS USUALLY PERFORMED UNDER US OR
CT GUIDANCE

19. CONTRAINDICATIONS
• INACCESSIBLE CYSTS
• SUPERFICIALLY LOCATED CYSTS
• CYSTS WITH MULTIPLE SEPTA
DIVISIONS (HONEYCOMBLIKE CYSTS
CE2, CE3B)
• CYSTS WITH HYPERECHOGENIC
SOLID PATTERNS ( CE4 )
• CYSTS COMMUNICATING WITH BILE
DUCTS
• PARTIALLY OR TOTALLY CALCIFIED
CYSTS (CE5
• MOST CYSTS IN THE LUNG.
INDICATIONS:
• INOPERABLE PATIENTS
• PATIENTS WHO REFUSE SURGERY.
• CYSTS TYPES CL, CE1, CE3, AND SOME CE2
(GHARBI TYPE I AND IL AND SOME PATIENTS WITH
TYPES LLI AND IV)
• RELAPSE AFTER SURGERY
• INFECTED CYSTS
• FAILURE OF CHEMOTHERAPY
• MULTIPLE CYSTS OF MORE THAN 5-CM DIAMETER
IN DIFFERENT LIVER SEGMENTS
• POSSIBLY PREGNANT WOMEN (CHEMOTHERAPY
CONTRAINDICATED)
• POSSIBLY CHILDREN LESS THAN 3 YEARS OLD.

20. COMPLICATION OF PAIR
• SPILLAGE AND ANAPHYLAXIS,
• RECURRENCE
• MECHANICAL DAMAGE TO OTHER TISSUE
• BILARY FISTULA
• HEMORRHAGE
• INFECTION
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

21. SURGICAL MANGEMENT
SURGERY IS STILL THE TREATMENT OF CHOICE FOR
UNCOMPLICATED HYDATID DISEASE OF THE LIVER.
• THE OBJECTIVES OF SURGICAL TREATMENT ARE TO:
(1) INACTIVATE THE SCOLECES,
(2) PREVENT SPILLAGE OF CYST CONTENTS,
(3) ELIMINATE ALL VIABLE ELEMENTS OF THE CYST, AND
(4) MANAGE THE RESIDUAL CAVITY OF THE CYST.
EARLY ON, SURGICAL MANAGEMENT OF HYDATID CYSTS
VIA CYST EVACUATION RESULTED IN A HIGH RATE OF
PERITONEAL IMPLANTATION. THIS PROBLEM PROMPTED
THE USE OF SCOLECIDAL AGENTS FOR INJECTION INTO THE
CYST AND FOR USE IN THE SURROUNDING PERITONEUM.
FORMALIN, HYPERTONIC SALINE, CETRIMIDE, HYDROGEN
PEROXIDE, POLYVINYLPURROLIDONE-IODINE, SILVER
NITRATE, AND ETHYL ALCOHOL ARE AMONG SOME OF THE
MANY AGENTS THAT HAVE BEEN USED

22. OPEN SURGICAL APPROACH
THE INCISION DEPENDS ON
• THE SITE OF THE OF THE CYST. CYST
• ITS SIZE
• THE PRESENCE OF EXTRAHEPATIC CYSTS
• THE PRESENCE OF COMPLICATIONS
A LONG RIGHT SUBCOSTAL INCISION WITH AN UPWARD
EXTENSION INTO MIDLINE IF NECESSARY
RIGHT THORACOABDOMINAL INCISION IS USED
INFREQUENTLY
A MIDLINE LAPAROTOMY IS PREFERRED WITH
• CYSTS IN THE LEFT LOBE OF THE LIVER
• PERFORATED ABDOMINAL HCS
• SECONDARY ABDOMINAL ECHINOCOCCOEIS.

23. RADICAL PROCEDURES
THE RATIONALE FOR RADICAL PROCEDURES IS THAT
(A) TOTAL REMOVAL OF THE CYST AND EXOCYSTS IS
ASSOCIATED WITH THE LOWEST RECURRENCE RATE,
(B) CHEMOTHERAPY AFTER RADICAL REMOVAL OF
THE INTACT CYST IS UNNECESSARY, (C) THE USE OF
INTRAOPERATIVE PROTOSCOLICIDAL AGENTS IS UNNECESSARY
IF THE CYST IS NOT ENTERED, (D) THE
CHANCE FOR A BILIARY FISTULA AND CAVITY-RELATED
COMPLICATIONS IS LOW (E) CALCIFIED CYSTS CAN
BE REMOVED, AND (F) IN EXPERT HANDS THE
MORTALITY AND MORBIDITY RATES ARE LOW.
RADICAL PROCEDURES ARE (A) CLOSED CYSTECTOMY.
(B) OPEN CYSTECTOMY. (C) NEAR-TOTAL
OPEN CYSTECTOMY. (D) SUBADVENTITIAL CYSTECTOMY.
(E) NONANATOMIC LIVER RESECTION, (F) ANATOMIC
LIVER RESECTION, (G) COMPLETION CYSTECTOPERICYSTECTOMY
IN RESIDUAL CAVITIES, AND
(H) TOTAL CYSTOPERICYSTECTOMY IN HEPATOPULMONARY
TRANSIT

24. PARTIAL CYSTOPERCYSTECTOMY IS
THE MOST FREQUENTLY EMPLOYED CONSERVATIVE
PROCEDURE. SEVERAL TECHNIQUES FOR THE SAFE
OBLITERATION OF THE RESIDUAL PERICYST CAVITY
HAVE BEEN DEVELOPED. THE METHOD OF
MANAGING OR OBLITERATING THE RESIDUAL CAVITY
SHOULD BE SELECTED CAREFULLY. 'IHE AVAILABLE
OPTIONSARE
(A) LEAVING THE CYST OPEN. (B) SIMPLE CYST
CLOSURE. (C) MARSUPIALIZATION. (D) EXTERNAL
TUBE DRAINAGE. (E) INTROFLEXION. (F)
CAPITONNAGE,
(G) OMENTOPLASTY, (H) PARTIAL CAPITONNAGE
PLUS OMENTOPLASTY
CONSERVATIVE PROCEDURE

25. SAFE DECOMPRESSION OF THE
HYDATID CYST.THE CYST IS
WALLED OFF WITH PACKS
SOAKED IN HYPERTONIC SALINE
AND PUNCTURED
WITH A LARGE-GAUGE NEEDLE
CONNECTED TO TRANSPARENT
PLASTIC SUCTION TUBING.AFTER
DECOMPRESSION.THE MOST
PROMINENT PART
OF THE CYST IS INCISED WITH
DIATHERMY TO ALLOW ENTRY
WITH. A SUCTION TIP. AFTER THE
LIQUID CYST CONTENTS HAVE
BEEN ASPIRATED, THE
OPENING IS FURTHER ENLARGED
AND ITS EDGES ARE SUSPENDED
BY ALLISON FORCEPS.
HYPERTONIC SALINE SOLUTION IS
INJECTED TO ENABLE
FURTHER ASPIRATION OF CYST
CONTENTS.

26. MANAGEMENT OF CYSTOBILIARY
COMMUNICATION
MANAGEMENT OF CBC IS THE CRUCIAL ISSUE IN
CONSERVATIVE SURGERY FOR LIVER HYDATIDOSIS.
MANAGEMENT OF CYSTOBILIARY COMMUNICATION
DEPENDS ON SEVERAL FACTORS INCLUDING AMONG MANY OTHER FACTORS
(A) THEIR NUMBER, (B) TYPE, (C) SITE, (D) SIZE OF THE ORIFCE, (E) THE INVOLVED
BILE DUCT (F) PATIENT STATUS (G) CONDITION OF THE LIVER, AND (H) THE EXPERTISE
OF THE SURGEON.

27. MANAGEMENT OFTHE RESIDUAL
CYST CAVITY
THE RESIDUAL CAVITY CAN BE A SOURCE OF
POSTOPERATIVE COMPLICATIONS IN INEXPERINCED
HANDS.
• LEAVING THE CYST OPEN
• SIMPLE CYST CLOSURE
• INTROFLEXION(CONSISTS OF
FOLDING IN AND
APPROXIMATING OPPOSITE
EDGES OF THE PERICYST
AND SUTURING THEM IN
PLACE)
• CAPITONNAGE (THERE IS
SPIRAL SUTURING FROM THE
• BOTTOM OF THE CAVITY
UPWARD.

28. MARSUPIALIZATION
EXTERNAL CYST DRAINAGE BY SUTURING THE
OPENING ON THE PERICYST TO THE ABDOMINAL
WALL HAS BEEN ABANDONED
OMENTOPLASTY
A VITAL OMENTAL FLAP IS
DEVELOPED
AND PLACED INTO THE REMAINING
CYST CAVITY.THE OMENTUM IS
SUTURED IN PLACE WITH SEVERAL
ABSORBABLE SUTURES.

29. LAPAROSCOPIC HYDATID SURGERY
LAPAROSCOPIC HYDATID SURGERY FOLLOWS
THE BASIC SURGICAL PRINCIPLES OF TREATING HYDATID
CYST BY THE OPEN APPROACH
EVACUATION OF THE CYST WITHOUT SPILLAGE, STERILIZATION
OF THE CAVITY. DETECTION OF MAJOR BILIARY COMMUNICATIONS
AND MANAGEMENT OF THE RESIDUAL CAVITY.
THE LAPAROSCOPIC EVACUATION OF THE HYDATID CONTENT
REQUIRES A POWERFUL ASPIRATOR AND A TROCAR WITH A LARGE
DIAMETER TO EXTRACT ALL VESICLES.
ANOTHER IMPORTANT ISSUE IN LAPAROSCOPIC
HYDATID CYST SURGERY IS THE REMOVAL OF THE
GERMINATIVE MEMBRANE.

30. • THE PATIENT UNDER GENERAL ANESTHESIA.
• PNEUMOPERITONEUM IS CREATED AND AN
• INTRA-ABDOMINAL PRESSURE OF 12 MM IS ACHIEVED.
• A 30-DEGREE SCOPE IS INTRODUCED THROUGH A 10-MM UMBILICAL PORT AND A
12-MM SUCTION CANNULA THROUGH A SUBXIPHOID PORT.
• TWO OTHER 5-MM TROCARS ARE PLACED AT THE STANDARD SITES USED FOR
LAPAROSCOPIC CHOLECYSTECTOMY
• A FIFTH 5-MM TROCAR IS PLACED ABOVE THE UMBILICUS ON THE LEFT SIDE

31. THE GERMINATIVE MEMBRANE IS REMOVED IN A
PLASTIC BAG AND EXTRACTED THROUGH THE
EPIGASTRIC PORT.
THE CYST CAVITY IS EXPLORED UNDER DIRECT
VIEW WITH THE CAMERA INSERTED INSIDE THE
CYST TO EXCLUDE RESIDUAL DAUGHTER CYSTS.
THE LAPAROSCOPIC APPROACH GIVES BETTER
VISUAL CONTROL OF THE CYST CAVITY BECAUSE OF
THE ADVANTAGE OF MAGNIFICATION WHICH ALLOW
THE DETECTION OF SMALL OPEN BILE DUCTS.
CONVERSION RATE RANGE FROM 4% TO 30%
DUE TO DIFFCULT AND UNSAFE EXPOSURE OF THE
CYSTS AND DUE TO DENSE INTRA-ABDOMINAL
ADHESIONS.

32. POSTOPERATIVE MANAGEMENT
• REPEAT US EXAMINATIONS AND CHEST RADIOGRAPHS
DURING THE IMMEDIATE POSTOPERATIVE PERIOD
• DETECT SUBDIAPHRAGMATIC ,SUBHEPATIC FLUID
COLLECTION AND DIAPHRAGMATIC PLEURISY AT AN
EARLY STAGE.
• PRACTICALLY ALL RESIDUAL CAVITIES DISAPPEAR BY
• 18 MONTHS AFTER OPERATION. CAVITIES PERSISTING
• AFTER THIS PERIOD NEED DIGNOSTIC WORKUP (A) US
MONITORING. (B) CT OR MRI. (C) SEROLOGY AND (D)
DIAGNOSTIC PUNCTURE

33. POSTOPERATIVE COMPLICATIONS
THE MOST FREQUENT POSTOPERATIVE COMPLICATIONS
ARE:
(A) WOUND INFECTION, (B) CHEST PROBLEMS (C)
SUBPHRENIC ABSCESS (D) BILLARY LEAKS (E) LIVER
ABSCESS

34. REFERENCES:
• FISCHER’S MASTERY OF SURGERY
• SABISTON TEXTBOOK OF SURGERY
• WHO WEBSITE
• PUBMED