CANCER RELAPSE OR INFECTION? A SYSTEMATIC REVIEW ON LEISHMANIASIS AFTER BONE MARROW TRANSPLANTATION

Objective: Evaluate the factors associated with infection by Leishmania spp. in Bone Marrow Transplant (BMT) recipients due to hematological malignancies, in relation to clinical profile, tumor diagnosis, infection treatment, general mortality, infection relapses and graft infection. Material and methods: The search was carried out on the PUBMED, Embase and Google Scholar platforms using the terms “Leishmaniasis”, “Hematopoietic Stem Cell Transplant”, and the appropriate Boolean operators. Rayyan® and Microsoft Excel® software were used to select articles and interpret results. Results: 72 articles were found. Six duplicates and 54 articles that did not focus on the association between leishmaniasis and BMT due to hematological malignancies were excluded. Only 12 articles were included in the review, from 2001 to 2023. Of these, 7 studies were series or case reports on leishmaniasis in patients undergoing BMT, totaling 9 clinical cases. 78% of patients were male, with a mean age of 41-years.Lymphoblastic and myeloid leukemias predominated (55.6%) and 66.7% of patients underwent allogeneic BMT. 55.6% of patients were affected by Graft-Versus-Host Disease (GVHD) and 33.3% had associated infections (cytomegalovirus and Aspergillus spp.). The most common symptoms of the infection were: pancytopenia (88.9%); splenomegaly (55.6%); fever (44.4%); digestive involvement (22.2%); and skin or mucosal involvement (22.2%). The diagnosis was based on the presence of amastigotes in the bone marrow biopsy. Before diagnosis, 55.5% of patients were submitted to different clinical hypotheses: hemophagocytic lymphohistiocytosis (60.0%); viruses (20.0%); and acute GVHD (20.0%). The majority (88.9%) were treated with intravenous liposomal amphotericin B (L-AmB), which affected renal function in 25% of patients. 44.4% had recurrences of the infection (on average 4.3-months after the first treatment). Only one patient experienced allograft rejection and death. Discussion: Leishmaniasis is common in immunocompromised patients, especially due to acquired immunodeficiency syndrome. However, the literature has increasing descriptions of cases in transplant recipients, mainly kidney and liver transplants (the most common transplants). Few reports have been made in the literature about such infection in BMT, this being the only review on the subject in the literature. Infection with Leishmania spp. should always be considered in the differential of febrile pancytopenias, especially with splenomegaly. However, the clinic can be varied and the symptoms will not always be definitive. In the reality of BMT, it is difficult to clinically differentiate leishmaniasis from recurrences of hematological tumors and complications associated with transplantation, as they all present very similar and non-specific findings (such as fever, splenomegaly and pancytopenia). Immunosuppression, due to neoplasia or BMT therapy, makes the diagnosis of protozoosis even more difficult. Conclusion: Infection with Leishmania spp. in hematological patients, especially those undergoing hematopoietic stem cell transplantation, it should not be forgotten by the hematologist, as it can cause severe morbidity, mortality, and clinical complications, especially in cases of late diagnosis.