Haematopoietic stem cell transplant in a case of mucopolysaccharidosis IV with Fanconi anaemia and bone marrow failure.

Mucopolysaccharidosis type IV (MPS IV; Morquio syndrome) is a rare lysosomal storage disorder characterised by skeletal dysplasia and multisystem involvement, while Fanconi anaemia (FA) is an inherited bone marrow failure syndrome associated with chromosomal instability and hypersensitivity to conditioning agents. The coexistence of these two disorders poses a unique therapeutic challenge, particularly when haematopoietic stem cell transplantation (HSCT) is indicated. We report a child with MPS IV and FA who underwent HSCT with a non-myeloablative conditioning regimen. The procedure was carefully individualised to balance engraftment success with minimisation of toxicity. This case highlights the complexities of managing overlapping genetic conditions requiring HSCT and demonstrates the value of multidisciplinary planning and personalised transplant strategies in achieving favourable clinical outcomes.