Khalaf Ahmed M, Hashim Mahmoud A, Alsharabati Mohammed, Fallon Kenneth, Cure Joel K, Pappas Peter, Mineishi Shin, Saad Ayman
Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Blood and Marrow Transplantation and Cellular Therapy Program, The University of Alabama at Birmingham, Birmingham, AL, USA.
Am J Case Rep. 2017 Mar 10;18:246-250. doi: 10.12659/ajcr.899687.
BACKGROUND Toxoplasmosis is an uncommon but potentially fatal complication following allogeneic hematopoietic stem cell transplantation (HCT). Post-transplant toxoplasmosis is often a reactivation of prior infection and typically occurs within the first 6 months of transplant. Herein, we report that cerebral toxoplasmosis may occur 22 months after allogeneic hematopoietic stem cell transplantation. CASE REPORT We describe a case of cerebral toxoplasmosis that occurred 22 months after an allogeneic HCT while the patient was on aerosolized pentamidine for Pneumocystis jiroveci pneumonia (PCP) prophylaxis. The disease was only diagnosed after brain biopsy because of atypical MRI appearance of the cerebral lesion and negative Toxoplasma gondii IgG antibody test result in the cerebrospinal fluid (CSF). The patient received pyrimethamine and sulfadiazine treatment, with dramatic improvement after several months. The patient is alive 2 years after infection diagnosis, with no evidence of disease and is off Toxoplasma prophylaxis. CONCLUSIONS Cerebral toxoplasmosis can occur late after allogeneic HCT while patients are on immunosuppression therapy, with atypical features on imaging studies and negative Toxoplasma gondii IgG antibody test result in the CSF. Pre-transplant serologic screening for T. gondii antibodies in allogeneic transplant candidates is warranted. Brain biopsy can be a helpful diagnostic tool for cerebral lesions.
背景 弓形虫病是异基因造血干细胞移植（HCT）后一种不常见但可能致命的并发症。移植后弓形虫病通常是既往感染的重新激活，典型地发生在移植后的前6个月内。在此，我们报告异基因造血干细胞移植22个月后可能发生脑弓形虫病。病例报告 我们描述了一例在异基因造血干细胞移植22个月后发生脑弓形虫病的病例，当时患者正在接受雾化喷他脒预防耶氏肺孢子菌肺炎（PCP）。由于脑病变的MRI表现不典型且脑脊液（CSF）中弓形虫IgG抗体检测结果为阴性，该疾病仅在脑活检后才得以诊断。患者接受了乙胺嘧啶和磺胺嘧啶治疗，数月后有显著改善。在感染诊断后2年患者仍然存活，没有疾病证据且已停用弓形虫预防药物。结论 异基因造血干细胞移植后晚期，在患者接受免疫抑制治疗时，脑弓形虫病可能发生，其影像学表现不典型且脑脊液中弓形虫IgG抗体检测结果为阴性。对异基因移植候选者进行移植前弓形虫抗体血清学筛查是必要的。脑活检对于脑病变可能是一种有用的诊断工具。
