Treatment of Hydatid Cyst in the Lung
Surgical excision is the primary treatment for pulmonary hydatid cysts, with complete excision conserving as much lung tissue as feasible, supplemented by pre- and post-operative antiparasitic medications. 1, 2
First-Line Management Approach
- Pulmonary cystic echinococcosis (CE) requires management in specialist centers following World Health Organization (WHO) Informal Working Group on echinococcosis guidance 1, 2
- Cases should be discussed at a specialist hydatid multidisciplinary team where parasitology, infectious diseases, and surgical specialist input is available 1
Surgical Treatment
- Complete surgical excision with maximum preservation of lung parenchyma is the treatment of choice for most pulmonary hydatid cysts 1, 3
- Common surgical techniques include:
- Pulmonary resection procedures like lobectomy should be avoided when possible, particularly in children 3
- Percutaneous aspiration, injection of chemical scolecidal agents and re-aspiration (PAIR), or aspiration alone, are contraindicated for lung cysts due to risk of anaphylaxis and dissemination 1, 2
Medical Treatment
- Praziquantel is given pre- and post-operatively 1
- Albendazole (more effective than mebendazole) is administered post-operatively 1, 7
- Standard dosing: 400 mg twice daily with meals for patients ≥60 kg 7
- For patients <60 kg: 15 mg/kg/day in divided doses twice daily with meals (maximum 800 mg daily) 7
- Duration depends on whether excised material was assessed as viable 1
- Typically given in 28-day cycles followed by 14-day albendazole-free intervals, for a total of 3 cycles 2, 7
Special Situations
- For inoperable lung cysts, albendazole may be given as a continuous treatment course 1
- Small lung cysts (<5 cm) may respond to medical treatment alone, though cyst rupture remains a risk 1, 2
- In patients with both lung and liver CE, management of lung cysts should be prioritized over liver cysts 1
Monitoring During Treatment
- Monitor blood counts at the beginning of each 28-day cycle and every 2 weeks during therapy with albendazole 7
- Monitor liver enzymes (transaminases) at the beginning of each 28-day cycle and at least every 2 weeks during treatment 7
- Obtain pregnancy test in females of reproductive potential prior to therapy due to risk of embryo-fetal toxicity 7
Potential Complications and Pitfalls
- Risk of bone marrow suppression with albendazole, particularly in patients with liver disease 7
- Discontinue albendazole if clinically significant decreases in blood cell counts occur 7
- Risk of anaphylaxis and cyst dissemination during interventional procedures is significant 2
- Recurrence rates are higher in patients with ruptured cysts prior to operation 6
- Larger cysts (>10 cm) are associated with higher complication and recurrence rates 4