**6. Conclusions**

All children demonstrated the features of cell damage already before alloHSCT; thus, the subclinical AKI is a common finding in this population. Clusterin seems more useful in the assessment of subclinical AKI than the classical indices of tubular (KIM-1) and glomerular (cystatin C) damage analyzed separately. It may become a new early marker of sublethal kidney injury in this group of patients.

**Author Contributions:** Conceptualization: K.M., M.A., D.Z.; investigation: K.M., M.A., I.M.-M., M.U.; resources: I.M.-M., K.K., M.U.; formal analysis: K.M.; writing—original draft: K.M. writing—review and editing: K.M., D.Z.; visualization: K.M.; funding acquisition: K.K., D.Z. All authors have read and agreed to the published version of the manuscript.

**Funding:** The project was financed by the Foundation "Na Ratunek Dzieciom z Chorob ˛a Nowotworow ˛a" (FNRD.C210.19.002).

**Conflicts of Interest:** The authors declare no conflict of interest regarding the publication of this manuscript.

**Ethical Standards:** All procedures were performed in accordance with the 1964 Helsinki declaration and its further amendments. The research project was approved by the Wroclaw Medical University ethics committee (decision no. KB-786/2018).
