Objective To evaluate the feasibility and toxicity of autologous haematopoietic stem cell transplantation (HSCT) for the treatment of refractory Crohn's disease (CD).

Design In this prospective study, patients with refractory CD suffering an aggressive disease course despite medical treatment, impaired quality of life and in whom surgery was not an acceptable option underwent HSCT. Toxicity and complications during the procedure and within the first year following transplantation were evaluated, along with the impact of the introduction of supportive measures on safety outcomes.

Results 26 patients were enrolled. During mobilisation, 16 patients (62%) presented febrile neutropaenia, including one bacteraemia and two septic shocks. Neutropaenia median time after mobilisation was 5 days. 5 patients withdrew from the study after mobilisation and 21 patients entered the conditioning phase. Haematopoietic recovery median time for neutrophils (>0.5×10⁹/L) was 11 days and for platelets (>20×10⁹/L) 4 days. Twenty patients (95%) suffered febrile neutropaenia and three patients (27%) presented worsening of the perianal CD activity during conditioning. Among non-infectious complications, 6 patients (28.5%) presented antithymocyte globulin reaction, 12 patients (57%) developed mucositis and 2 patients (9.5%) had haemorrhagic complications. Changes in supportive measures over the study, particularly antibiotic prophylaxis regimes during mobilisation and conditioning, markedly diminished the incidence of severe complications. During the first 12-month follow-up, viral infections were the most commonly observed complications, and one patient died due to systemic cytomegalovirus infection.

Conclusions Autologous HSCT for patients with refractory CD is feasible, but extraordinary supportive measures need to be implemented. We suggest that this procedure should only be performed in highly experienced centres.