title: [Diagnostic imaging for the study of popliteal masses in dialyzed patients].
abstract: A new type of amyloidosis, secondary to the massive deposition of beta 2-microglobulin, has been identified which is peculiar to long-term (greater than or equal to 5 years) hemodialysis. Popliteal masses have recently been described as a possible manifestation of this type of amyloidosis. We report the results of a clinical-radiologic study of the popliteal region in 28 patients (14 males, 14 females; age 52.9 +/- 12.6 years) undergoing chronic hemodialysis for 60-212 months (mean 127 +/- 40). We aimed at determining the role of diagnostic imaging (conventional radiography, ultrasonography, Computed Tomography) in this pathologic condition. Clinics detected popliteal masses in 4 patients (bilateral in 1). US allowed 2 more cases to be detected and demonstrated the cystic nature of the lesion. Ultimately, popliteal masses could be demonstrated in 6 (bilateral in 5) of 28 patients (incidence 21.4%). In the 3 patients who were investigated by CT, cysts were seen to communicate with the joint cavity (Baker's cysts). In 1 case, immunocytochemical analysis showed diffuse beta 2-microglobulin positive amyloid deposition within the synovial wall of the surgically removed cyst. All the 6 patients experienced some of the major features of dialysis-related amyloidosis: carpal tunnel syndrome (6 cases), destructive arthropathy (5 cases), carpal and shoulder bone radiolucencies (5 and 4 cases, respectively). These findings, while documenting the high prevalence of popliteal cysts among long-term hemodialysis patients and the strong correlation with dialysis-related amyloidosis, stress the importance of diagnostic imaging in the detection and follow-up of such lesions.
authors.affiliation: Servizio di Nefrologia e Dialisi, Ospedale M. Bufalini, Cesena, Forlì.
authors.forename: L
authors.initials: L
authors.lastname: Baldrati
authors.forename: B
authors.initials: B
authors.lastname: Balbi
authors.forename: A
authors.initials: A
authors.lastname: Rocchi
authors.forename: R
authors.initials: R
authors.lastname: Bonsanto
authors.forename: D
authors.initials: D
authors.lastname: Docci
authors.forename: C
authors.initials: C
authors.lastname: Capponcini
authors.forename: C
authors.initials: C
authors.lastname: Feletti
authors.forename: M
authors.initials: M
authors.lastname: Mughetti
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000686:Amyloidosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011151:Popliteal Cyst / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D006435:Renal Dialysis / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography