Hydited Cyst

Question 1

Cause of the Hydatid Cyst

Answer 1

Infection by tape worm Echinococcus granulosus

Question 2

Definitive host

Answer 2

Dogs and other carnivores

Question 3

The cyst wall secreted by the embryo consist of 2 layers

Answer 3

Ectocyst
Endocyst

Question 4

Intermediate host

Answer 4

Sheep, pig, or accidentally man

Question 5

Pathology

Answer 5

Usually solitary and most often in the right lobe
▪ A cyst develops which grows slowly and differentiates into:
1. Adventitia: an outer fibrous layer formed by the host tissue.
2. Ectocyst: (laminated membrane) in the middle. It is whitish and elastic.
3. Endocyst: An inner single germinal layer of cells which secretes hydatid fluid and form ectocyst and broad capsules.
4. The cyst is filled with clear fluid containing scolices of future worms, brood capsules formed by Endocyst& daughter cysts, ( free separated broil capsules)

Question 6

Complications

Answer 6

1. Secondary infection = Pyogenic liver abscess
2. Rupture of the cyst into:
   - Biliary Tract
   - Peritoneal cavity = dissemination and anaphylaxis
   - Pleura = empyema
   - Lung = bronchopleural fistula.
   - Bowel or death and calcification = mean the cyst is inactive, infertile with spontaneous cure and no treatment is needed.
   - blood stream = anaphylaxis and systemic echinococcosis.

Question 7

C / P :

Answer 7

• Small cysts are symptomless & may be discovered accidentally during US or CT scan.
• Painless, well-defined, fluctuating abdominal swelling.
• Dull aching pain in the right hypochondrium and right shoulder.
• Attacks of urticaria with eosinophilia and dyspepsia.
  5. Manifestations of complications.
  ( Right upper quadrant pain / Dyspepsisa / vomiting / non specific fatigue / weight loss / Hx of fever / allergy )

Question 8

Investigations

Answer 8

1. Ultrasonography and C.T. Scan ( the most important)
2. Casoni’s test is not reliable
3. ELISA or complement fixation test which detect hydatid antibodies in the serum are the sure diagnosis.

Question 9

Treatment

Answer 9

1. Small asymptomatic cysts need just follow up by u/s and C.T.
2. Laparoscopic Surgery is the standard treatment for large symptomatic cyst.
   - Exicision after sterilization of the cyst contents.
   - PAIR ( Puncture, Aspiration, Injection of hypertonic saline and Reaspiration)
   - Partial hepatectomy for easily accessible large or multiple cysts.
3. Medical treatment: Unfit patient or recurrent cases, Pre and post operative to prevent recurrence.

Question 10

Signs

Answer 10

Palpable right upper quadrant mass
Jaundice
Malnutrition
Pleural effusion
Cholangitis
Splenomegaly
Dyspnea, asthma
Edema of extremists
Pancreatitis