title: Incidental Diagnosis of an Asymptomatic Hydatid Cyst Through Low-Grade 18F-FDG Uptake in the Peripheral Rim.
abstract: Here we present a case of an untreated, asymptomatic, pulmonary hydatid cyst incidentally diagnosed on the basis of atypically low-grade (18)F-FDG uptake in the peripheral rim and a minimal increase in uptake on dual-point (18)F-FDG PET/CT. The patient underwent (18)F-FDG PET/CT for characterization of a solitary lung lesion found on chest radiography and inconclusive findings on contrast-enhanced CT. Although the diagnosis was confirmed by a serum indirect hemagglutination assay positive for Echinococcus granulosus, the low-grade (18)F-FDG uptake in the context of the asymptomatic presentation was noteworthy, as it could be related to minimal active inflammation. Our case, together with similar previously published findings, leads to the hypothesis that inflammatory (18)F-FDG uptake may be an additional determinant of the cause of symptoms in these patients.
authors.affiliation: Radiation Medicine Centre (BARC), Tata Memorial Hospital Annexe, Parel, Mumbai, India; and.
authors.forename: Nandigam S
authors.initials: NS
authors.lastname: Kumar
authors.affiliation: Department of Pulmonary Medicine, T.N. Medical College, B.Y.L. Nair Hospital, Mumbai, India.
authors.forename: Ketaki
authors.initials: K
authors.lastname: Barve
authors.affiliation: Department of Pulmonary Medicine, T.N. Medical College, B.Y.L. Nair Hospital, Mumbai, India.
authors.forename: Jyotsna
authors.initials: J
authors.lastname: Joshi
authors.affiliation: Radiation Medicine Centre (BARC), Tata Memorial Hospital Annexe, Parel, Mumbai, India; and drsanb@yahoo.com.
authors.forename: Sandip
authors.initials: S
authors.lastname: Basu
mesh_terms: D058070:Asymptomatic Diseases; D001692:Biological Transport; D004443:Echinococcosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism*; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D006801:Humans; D033162:Incidental Findings; D008297:Male; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: 18F-FDG PET/CT; echinococcus; hydatid cyst; inflammation