Bone Microarchitecture in the Transplant Patient (TRANSOS)

Longitudinal Monitoring of Bone Microarchitecture by High Resolution Peripheral Quantitative Computed Tomography of (HR-pQCT) in the Transplant Patient

The optimal management of calcium and phosphate metabolism regulation in chronic kidney disease (CKD) is important in preventing fracture risk and vascular calcification and thus morbidity and mortality, global and vascular.

Kidney transplant in a CKD context, usually with a pre-existing underlying renal osteodystrophy, malnutrition, chronic inflammation, hypogonadism and immunosuppression protocols still often made up of high-dose corticosteroid therapy, are all theoretical factors of post-transplantation bone disease. For other solid organ transplants, even though there is generally no underlying renal osteodystrophy before the transplant, the proportion of osteoporotic patients at the time of transplant is substantial. The bone risk in the immediate post-transplant period is notable.

Patients' follow-up is based on biological, radiological and histological tools. Bone densitometry (DXA) is used to measure bone mass. However, recent international recommendations do not consider DXA as a valid tool to assess bone health in CKD patients. Moreover, it is less informative than peripheral quantitative tomography resolution (HR-pQCT). This latest technique, available in Lyon and Saint-Etienne, is more precise, allowing a three-dimensional study of the trabecular microarchitecture and compartmental volumetric bone density (total, cortical, trabecular), while similar to DXA in terms of radiation (less than 5 μSv). The prevention of cardiovascular risk factors is also part of the daily care of patients with a regular cardiac monitoring (heart ultrasound) and vascular (blood pressure, Doppler of the supra-aortic trunks).

TRANSOS study aims to evaluate in a prospective cohort (longitudinal follow-up of 6 months), the bone status in patients receiving solid organ transplantation in the University Hospitals of Lyon and Saint-Etienne, using DXA and HR-pQCT (at baseline and month 6), in combination with classical biological and cardiovascular monitoring. Transplantation is an important activity in these two hospitals and this protocol provides the same bone follow-up for all solid organ transplants, with a reliable, efficient, non-invasive and low-dose radiation tool.

The primary objective of TRANSOS study is to evaluate changes in tibial cortical density between the baseline and the 6th month post-transplant measured by HR-pQCT.

Study Overview

• Status: Completed
• Conditions: Organ Transplant
• Intervention / Treatment: Procedure: Tibial cortical density evaluation

• Study Type: Interventional
• Enrollment (Actual): 137
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Bron, France
    • Hôpital Femme Mère Enfant
  • Lyon, France
    • Hopital Edouard Herriot
  • Saint-Étienne, France
    • CHU Saint Etienne

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient over 10 year-old
• Patient receiving a first solid organ transplant within involved hospitals (Lyon, Saint Etienne): kidney, heart, kidney-pancreas, lung
• Informed consent signed by the patients or their parents (minors)

Exclusion Criteria:

• No health cover
• Ongoing pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tibial cortical density evaluation	Procedure: Tibial cortical density evaluation; Bone evaluation in transplant patients will be performed by HR-pQCT at baseline (either within 6 months before surgery or within 15 days following surgery) and 6 months post-intervention in order to assess its evolution.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Tibial cortical density measured by HR-pQCT	at 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
trabecular bone area measured by HR-pQCT		at 6 months
total bone area measured by HR-pQCT		at 6 months
trabecular number measured by HR-pQCT		at 6 months
trabecular thickness measured by HR-pQCT		at 6 months
trabecular separation measured by HR-pQCT		at 6 months
cortical perimeter measured by HR-pQCT		at 6 months
Evaluation of bone markers by measuring calcium		at 6 months
Evaluation of bone markers by measuring phosphate		at 6 months
Evaluation of bone markers by measuring alkaline reserve		at 6 months
Evaluation of bone markers by measuring PTH		at 6 months
Evaluation of bone markers by measuring 25OHD3		at 6 months
Evaluation of bone markers by measuring 1-25 OHD3		at 6 months
Evaluation of bone markers by measuring FGF23		at 6 months
Evaluation of bone markers by measuring CTX		at 6 months
Evaluation of bone markers by measuring total alkaline phosphatase		at 6 months
Evaluation of bone markers by measuring bone alkaline phosphatase		at 6 months
Evaluation of bone markers by measuring osteocalcin		at 6 months
Bone mineral density assessed by DXA		at 6 months
Fractures onset assessed by DXA		at 6 months
Cardiovascular events (death from cardiovascular cause, heart attack, stroke)		at 6 months
PTH	For kidney transplant only	Baseline
1-25 OHD	For kidney transplant only	Baseline
FGF 23	For kidney transplant only	Baseline
calcium	For kidney transplant only	Baseline
phosphate	For kidney transplant only	Baseline

Collaborators and Investigators

• Sponsor: Hospices Civils de Lyon
• Investigators: Principal Investigator: Charlene LEVI, Doctor, Hospices Civils de Lyon

Publications and helpful links

General Publications

• De Mul A, Leclerc AS, Ginhoux T, Levi C, Confavreux C, Aurelle M, Portefaix A, Bacchetta J. Changes in bone density and microarchitecture in adolescents undergoing a first kidney transplantation: a prospective study. Eur J Pediatr. 2024 Dec;183(12):5303-5312. doi: 10.1007/s00431-024-05777-z. Epub 2024 Oct 9.

Study record dates

Study Major Dates

• Study Start (Actual): June 7, 2016
• Primary Completion (Actual): October 8, 2020
• Study Completion (Actual): October 8, 2020

Study Registration Dates

• First Submitted: March 25, 2016
• First Submitted That Met QC Criteria: March 31, 2016
• First Posted (Estimated): April 6, 2016

Study Record Updates

• Last Update Posted (Actual): August 22, 2025
• Last Update Submitted That Met QC Criteria: August 20, 2025
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Keywords: transplant; bone microarchitecture; HRpQCT
• Other Study ID Numbers: 69HCL14_0223; 2015-A00510-49 (Other Identifier: IDRCB)