Discussion
Currently, a clinical diagnosis of pulmonary hydatid is based on chronic respiratory symptoms, supported by compatible radiologic findings and hydatid serology. However, imaging findings in a complicated cyst can overlap with lung abscess, tuberculosis, tumor, Wegener’s granulomatosis, bronchiectasis, pneumothorax or empyema. Serology in pulmonary haydatidosis has lower sensitivity than hepatic hydatidosis. It can be false positive in other helminthic infections, cancer, chronic immune disorders, liver cirrhosis, presence of anti P1 antibodies, etc; and may be false negative if the cyst is unruptured3. Thus it would be helpful if better diagnostic modalities are available.
There is no consensus regarding the place of bronchoscopy in diagnosis. To the best of our knowledge, this is the first series reporting FFOB under conscious sedation, in pediatric lung hydatid.
However, multiple reports in adult patients documented the unexpected visualization of hydatid membranes during procedures performed for persistent respiratory symptoms or radiological shadows. In a retrospective analysis of 386 cases of lung hydatid, bronchoscopy performed prior to surgery in 106 patients helped in establishing the diagnosis in 21 patients4. In another retrospective study of 72 patients with pulmonary hydatid, bronchoscopy performed in 34 patients showed cyst membranes in 7 patients5. Other non-specific findings described by the authors included airway hyperemia, edema, purulent secretions and extrinsic compression. The relatively higher diagnostic yield in our series could be because most children had complicated cysts.
Our experience suggests that FFOB with BAL (performed under conscious sedation) could be an effective diagnostic modality, especially since radiology findings or serology may be inconclusive even in suspected cases. However, the procedure should be performed with great caution, with preparedness for managing complications.