high gvhd prevalence in travel-based sct despite young patients and hla matching

Background: patients from regions without stem cell transplantation (sct) facilities often seek treatment abroad and return home for post-transplant care. although extensive data exist on graft-versus-host disease (gvhd) and its risk factors, information on international sct patients returning to countries that lack transplant facilities and expertise is scarce and not well documented. materials and methods: we screened 149 transplant recipients and analyzed the data of 91 patients who received transplants abroad and were followed up at our center from january 2019 to december 2022. this observational study used data from electronic medical records and employed descriptive statistics, inferential tests, and relative risk calculations with forest plots to analyze the prevalence of gvdh and its key risk factors. results: of the recipients, 31.8% were residents of nine countries residing in the uae, and 67.2% were uae citizens. adults comprised 48.3% of the recipients, whereas 51.7% were pediatric patients. hematological malignancy was the most common indication (49%), primarily in adults. siblings comprised the majority of donors (52.6%), followed by related (23.09%) and unrelated donors (8.9%). most patients (69.2%) received hla-identical transplants, followed by 21.9% who received haplo-identical transplants. among adults, 62.2% developed gvhd compared to 26% of pediatric patients. recipients from related hla-identical donors had a 50% prevalence of gvdh, whereas those from unrelated identical donors had a 71% prevalence. the overall prevalence of gvdh was 50% in 87.9% of patients who received allogeneic scts. conclusion: despite favorable factors, such as young age and matched related donors, we found a high prevalence of gvdh. ocular gvhd was less prevalent than expected, and lung gvhd was weakly correlated with established risk factors. larger multicenter studies are needed to assess and confirm the effect of contributing factors.