TRANSPLANTATION RECIPIENTS. A COMPARATIVE STUDY OF DEXA AND ULTRASOUND MEASUREMENTS. S.Banolone, N.Morabito, L.Bartolone, D.Larosa, SPansera, N.Frisina. Dipartimento di Madicina Iutema 9 Terapia Medica, Universita di Medina. Background. Kidney transplantation recipients are patients at high risk for bone mineral density (BMD) loss and bone fractures, due to exposition to multiple factors. In the current literature, the degree oi osteoporosis in these patients has been evaluated by Dual Energy X-ray Absorptiometry (DEXA), but never, in our knowledge, by ultrasound (US) parameters. Aim of the study and Materials and Methods. We evaluated BMD in 19 kidney transplantation recipients (10 M, 9 F; age 25-60 yrs, time of dialysis 1-6 yrs, time from transplantation 2-15 yrs) comparing two different tecniques: 1) DEXA (SOPHOS) on lumbar spine at L1-L4 and femoral neck; 2) US bone velocity (UBV: DBM Sonic 1200 R). Results. Following WHO criteria based on BMD T-score, DEXA values detected osteoporosis in 6/19 (32%) pts, osteopenia in 8/19 (42%) pts and normal BMD in 5/19 (26%) pts. UBV was altered in all DEXA osteoporotic and osteopenie pts and showed altered values also in 3/5 normal DEXA pts. These 3 patients, however (all men), showed DEXA BMD values (g/cm 2) clearly decreased if compared to those of a sex and age-matched control group Conclusions. I) Our preliminary data confirm the very high prevalence of bone loss in kidney transplantation recipients (74 and 89~ by DEXA and UBV, respectively). 2) The absence of false negative cases (0/19) to US and the low frequency of discrepancies between DEXA and US results (3/19, however presenting subtle osteopenic signs to a subsequent evaluation) are promising featui'es that could lead (if confirmed on a larger number of subjects) to the utilization of US bone measurements as a reliable screening test for the detection of BMD alterations in transplanted recipients.