Cross-Sectional Analysis of Renal Transplantation Osteoporosis

Abstract

We report a cross-sectional study of 54 adult female renal transplant recipients. We measured bone mineral density (BMD) of the lumbar spine, femoral neck, total hip, and mid-and total radius, and 38 patients underwent transiliac crest bone biopsy. Osteopenia was widespread with 31/54 (57%) of patients osteoporotic at one or more sites. Seventeen out of 54 (32%) of the patients had a prevalent low-trauma fracture. There was a clear trend in BMD reduction across spine, hip and midradius, with the predominantly cortical midradial site showing the greatest loss. We found no relationship between BMD and body mass index, parathyroid hormone (PTH), dose of immunosuppressant, years since transplantation, age at menopause, or years since menopause. Histologically, abnormal biopsies could be classified into three categories: hyperparathyroid (n = 20), adynamic (n = 14), and osteomalacic (n = 2). Mean PTH was lower (p = NS) and mean cumulative prednisolone dose was higher (p = 0.04) in the adynamic group compared with the hyperparathyroid group, but because of overlap between groups neither was an effective discriminator of histology. We suggest that bone biopsy is indicated in these patients to direct appropriate treatment. At the cellular level, there were significant negative correlations between osteoclast function (eroded surface, r = 0.47, p = 0.003) and osteoblast numbers (osteoblast surface, r = -0.40, p = 0.01) and cumulative exposure to prednisolone. We postulate that suppression of osteoblast function by prednisolone with unopposed bone resorption may result in relative hypercalcaemia and low PTH. This progressive reduction in bone turnover may promote or prolong the adynamic

Comparison of intact and 'whole molecule' parathyroid hormone assays in patients with histologically confirmed post-renal transplant osteodystrophy

“…7 This was a histological classi¢cation, with hyperparathyroidism being classed as the presence of two out of three of the following: increased eroded bone surfaces, elevated osteoclast surface and increased osteoclast numbers. In the adynamic bone disease group, measurements of osteoblast surface, osteoid thickness and osteoclast numbers were all within or below the reference range for age-and gender-matched controls.…”

Improvement of adynamic bone disease after renal transplantation

“…For example, Faugere et al (21) reported a high prevalence of low bone turnover and osteomalacia after RT. Similarly, Parker et al (22) described a pro-gressive reduction in bone turnover which could promote or prolong the adynamic state. However, these were cross-sectional studies performed in mostly symptomatic patients, with various follow-up times.…”

“…However, these were cross-sectional studies performed in mostly symptomatic patients, with various follow-up times. Under the conditions described in the study of Parker et al (22), it would not be possible to determine the pre-RT pattern of bone turnover. Therefore, our findings cannot be compared to those from these studies.…”

KOSTNYY METABOLIZM I POTERYa KOSTNOY TKANI V OTDALENNYE SROKI POSLE ALLOTRANSPLANTATsII TRUPNOY POChKI (ATP) (ODNOMOMENTNOE ISSLEDOVANIE)

“…Остеопения, остеопоpоз и пеpеломы pазличной ло-кализации -частое осложнение после пересадки почки [9,16,17,18,21]. По данным одномомент-ных исследований, до 40-45% реципиентов как в ранние, так и отдаленные сроки после аллотpанс-плантации тpупной почки (АТП) имеют остеопе-нию, а от 10% до 50% пациентов -остеопороз [7,10,13,14].…”

“…Показано, что у женщин-реципиентов значительнее подавлен синтез остеобластами кальцийсвя-зывающего белка остеокальцина [1,2], и риск развития ос-теопороза и переломов костей у них повышен [17]. Однако данные о непосредственной связи между потерями костной ткани и биохимическими маркерами костного обмена [3,14,15], а также между снижением МПК и иммуносупрес-сивной терапией [3,6,8,9,12,14,15,16] в отдаленные сроки после АТП противоречивы. Вместе с тем, по мнению некоторых исследователей, гиперпаратиреоз и связанный с ним повышенный костный обмен -основные предикторы костных потерь в отдаленные сроки после АТП [7,8,14,19].…”