Pulmonary hydatid cyst is caused by the larval stage of the Echinococcus tapeworm. It is most commonly caused by E. granulosus. The lungs are a common site of infection after the liver. Symptoms include chest pain, cough, and dyspnea. Diagnosis involves imaging like chest X-ray and CT scan showing cysts. Serological tests can also detect antibodies. Surgical resection is the treatment of choice for large cysts, while smaller cysts may be treated with albendazole. Prevention involves avoiding contact with stray dogs that can spread the tapeworm.

1. Pulmonary Hydatid Cyst
By :Darayus P.Gazder (DPG)

2.  Echinoccosis or hydatid disease is caused by
larval stage of the echinococcus tapeworm
 Four species
 E. granulosis
 E. multilocularis
 E. vogeli
 E. oligarthrus
 Vast majority of infestations in humans are
caused by echinococcus granulosis
 Worldwide distrubution are concentrated in sheep
raising areas

3. Map shows areas in which hydatid disease is endemic due to the transmission of E
granulosus by means of the dog-sheep cycle (solid red areas).
Red stripes indicate areas where transmission occurs by means of alternative life cycles in which carnivores such as
wolves and foxes serve as definitive hosts and goats, camels, and horses serve as intermediate hosts

5. CLINICAL FEATURES
 Lungs are the second most common site of haematogenous
spread in adults
 INCIDENCE
Rural > Urban
Male:Female ----- 5:1
Lower lobes R>L
AGE: 20-40 Years (MC)
Most common site in children (25%)
Pulmonary increase in size 1-5cm per year
Symptoms: Chest pain, cough, haemoptysis, dyspnoea,
fever, salty sputum, allergy, fragments of hydatid
membrane or scolices

6. Investigations:
 Chest X-ray:
1. Dense homogeneous opacity
2. Crescenteric cap of air
3. Water lily Appearance.
 Blood shows eosinophilia: 15-20%
 Positive Casoni’s test: +ve in 50% of cases.
 Serodiagnosis: Detection on antigen/ antibodies due to parasite by Elisa
 Indirect hemagglutination test: +ve in 60-100% cases
A fixed amount of anti-echinococcus antibodies is mixed with fixed amount of red blood
cells coated with antigens. A positive IHA test is indicated by formation of the a ‘mat’ or
‘carpet’ cells at the bottom of the well.
 CT scan diagnostic

7. Unruptured echinococcus cysts

8. Crescent sign-cap of air, when it communicates into bronchial tree.
Consider this as sign of impending rupture and indication for emergency
thoracotomy

10. Complications
 Pulmonary Embolism
 Rupture -- allergic symptoms and anaphylaxis
-severe hypotension and death
 Rupture - trans bronchial spread to other lobes/
pleural effusion/ Pneumothorax/ Anaphylaxis
 Hepatobronchial fistula formation (produces
bilious sputum)
 Infection -- abscess formation and septicemia
 Calcification - rare

11. D/D
 Lung cancer
 Lung abscess
 Epithelial cysts
 Aspergillosis

12. MANAGEMENT
 Small cyst< 2-3 cm-----Medical treatment –
Albendazole- 3-4 weeks
 Larger cysts>4-6 cm---- Surgical resection, preop
Albendazole atleast 4days prior to surgery and
continue for 3-6 months after surgery.
 IF THE HYDATID CYST OCCUPIES MORE THAN
50% OF A LOBE ----- LOBECTOMY

13. Surgery is considered the treatment of choice
Parasite can be completely removed and the patient cured.
Prevent spill of cyst contents to avoid intra-operative
dissemination and recurrence
 Delivery of intact cyst
 Cyst fluid aspiration ± use of scolicidal solution
 Hypertonic saline, povidine iodine, formalin, ethanol,
hydrogen peroxide, 1% formalderhyde
 Agent must remain in contact with cyst for at least 15
minutes

14. Prevention:
 Avoid close contact with dogs.
 Wash hands after handling of dogs.
 Avoid contact with dog feces.
 Vegetables, fruit should be thoroughly washed.
 Prevent dogs from roaming or having access to
raw sheep meat or viscera.
 All sheep carcasses should be disposed of
correctly and immediately.
Thank you!!

15. References
Baileys and Love’ Short Practice of Surgery
Manipal manual of Surgery
SRB Manual of Surgery
Bedside Clinics in Surgery
http://radiographics.rsna.org
www.emedicine.com