Pulmonary manifestations and clinical management of echinococcosis in a low-endemic region of Mexico: a 15-year retrospective cohort study at a tertiary hospital.

Background: Cystic echinococcosis has a low incidence even in endemic countries. It is a chronic and complex zoonosis that in many cases presents delay in diagnosis; it typically affects the liver in up to 90% of the cases, being disseminated pulmonary disease the most common in young subjects, while the rate of cases located only in the pulmonary parenchyma is low. In Mexico it is considered a disease of low endemicity.

Material and methods: We retrospectively collected data from patients with suspected echinococcosis infection from the hospital discharge database.

Results: Of the 70 patients in the database, 59 had a clinical history (84.3%), of whom 11 had a histopathological diagnosis of cystic echinococcosis and were included in this study, 67.6% were female, with a median age of 32 years (IQR 17-53.5). A total of 45.6% had some comorbidity, the most frequent being type II diabetes mellitus (80%); only 54.6% had lived in a rural area as a risk factor, while only 27.2% had exposure to canines. All cases were symptomatic, with a mean symptom duration of 49 days. A total of 81.8% had exclusive pulmonary disease, while the rest had simultaneous lung and liver involvement. No case presented spontaneous rupture. All cases received anthelmintic treatment and, in 9 cases, surgical resection of the pulmonary parenchyma. The only postsurgical complication was a chylothorax with adequate resolution. The median follow-up in months was 8.3 (IQR 3.7 to 10.7 months), and almost two-thirds of the cases presented dyspnea grade 2-3 (mMRC) as sequelae.

Conclusion: Of all the patients studied with pulmonary echinococcosis, only two presented with hepatic-pulmonary hydatid disease, and spontaneous cyst rupture was not reported. About half had exposure to cattle as a risk factor, while no specific risk factor was identified in the rest of the subjects.