Relevance of Pulmonary Alveolar Echinococcosis.

Background: Pulmonary alveolar echinococcosis (PAE) is a chronic disease caused by Echinococcus multilocularis with very low incidence in developed countries.

Methods: This single-center, retrospective study included 34 patients who were diagnosed with PAE between January 2001 and February 2019 (15 males, 19 females, mean age: 52.4±15.8 years, age range: 28-78 years) in Ataturk University Medical School, Erzurum, Turkey.

Results: The liver was the primary involved organ in all cases. Pulmonary involvement was detected in 13.0% (34/261) of all cases with hepatic alveolar echinococcosis (AE), and three patients (8.8%) had both pulmonary metastasis and brain metastasis. The route of spread to the lungs based on radiological data was hematogeneous in 25 patients (73.5%), transdiaphragmatic in three patients (8.8%) and both hematogeneous and transdiaphragmatic in six patients (17.7%). AE showed bilateral involvement in 19 patients (55.9%), whereas only the right lung was involved in 12 patients (35.3%) and the left lung in three patients (8.8%). Of the patients, five underwent surgery due to PAE and 29 patients received medical therapy with albendazole. A total of three patients died during the follow-up period (2, 5 and 10 years after the diagnosis of PAE), while 31 patients continued with follow-up and treatment for a mean duration of 5.4±3.8 years (1-14 years).

Conclusions: Patients with hepatic AE must, as a matter of course, be screened for possible lung involvement. Albendazole therapy may slow down disease progression in patients with widespread pulmonary involvement who are not eligible for surgery.