Prospective Validation of Engraftment Syndrome Phenotypes and Outcomes After Hematopoietic Stem Cell Transplantation

A Prospective Observational Cohort Study to Validate Engraftment Syndrome Phenotypes and Their Associations With Acute Graft-Versus-Host Disease and Clinical Outcomes After Hematopoietic Stem Cell Transplantation

Engraftment syndrome (ES) is an early inflammatory complication after hematopoietic stem cell transplantation (HSCT) and has been associated with subsequent transplant-related complications and adverse clinical outcomes. However, ES is clinically heterogeneous, and its relationship with acute graft-versus-host disease (aGVHD), survival, and other post-transplant outcomes remains incompletely defined.

This prospective observational cohort study aims to validate previously identified ES-associated risk factors, severity-oriented ES phenotypes, and their associations with grade II-IV aGVHD and clinical outcomes after HSCT. Patients undergoing HSCT will be prospectively followed for the development of ES, grade II-IV aGVHD, and clinical outcomes including overall survival, disease-free survival, relapse, and non-relapse mortality. The study will evaluate whether ES phenotypes and ES-related clinical characteristics can stratify patients according to subsequent aGVHD risk and post-transplant prognosis.

Inclusion Criteria:

1. Patients undergoing allogeneic hematopoietic stem cell transplantation at the participating center.
2. Development of engraftment syndrome after hematopoietic stem cell transplantation, diagnosed according to predefined institutional or published clinical criteria.
3. Availability of key clinical and laboratory data required for engraftment syndrome phenotyping, including engraftment kinetics, clinical manifestations, inflammatory markers, and organ-injury parameters.
4. Ability to undergo prospective follow-up for post-transplant outcomes, including acute graft-versus-host disease and survival outcomes.
5. Written informed consent provided by the patient or legally authorized representative, when required by the institutional review board or ethics committee.

Exclusion Criteria:

1. Patients who do not develop engraftment syndrome after hematopoietic stem cell transplantation.
2. Patients with insufficient clinical or laboratory data to confirm the diagnosis of engraftment syndrome.
3. Patients with missing essential follow-up information for assessment of primary outcome measures.
4. Patients who withdraw consent or decline participation in prospective follow-up.
5. Patients enrolled in another study that, in the opinion of the investigators, may interfere with the observational assessment of engraftment syndrome phenotypes or post-transplant outcomes.