Pitfalls in the diagnosis of complicated pulmonary hydatid disease.

The aim of this study was to present the pitfalls in the diagnosis of complicated pulmonary hydatid disease and to discuss the unusual radiological presentations of this endemic disorder in Turkey. We retrospectively evaluated 34 patients (12 females) aged between 8 and 64 years, who were operated on at our centre between 1991 and 1998 and diagnosed with complicated pulmonary hydatid cyst histopathologically. Computerized tomography (CT) scans of these patients were reviewed double-blind by two radiologists. The patients were then divided into two groups: group 1: initial radiological impression is pulmonary hydatid cyst and group 2: initial radiological impression is not pulmonary hydatid disease. These two groups were evaluated in terms of symptoms, radiographical presentation and laboratory tests. The presence of cystic appearance, water-lily sign, ring enhancement concomitant with intact cysts unanimously led the radiologists to the diagnosis of complicated pulmonary hydatid cyst, whereas solid appearance and presence of bronchial obliteration made the diagnosis unlikely. In such circumstances patient history, laboratory findings and bronchoscopic evaluation helped the diagnosis. In conclusion, in endemic regions like Turkey, atypical radiological presentation of complicated pulmonary hydatid disease should be considered in the differential diagnosis of solid pulmonary lesions.