Department of Internal Medicine C (Haematology and Oncology, Marrow Transplantation), Ernst-Moritz-Arndt-University Greifswald, Ferdinand-Sauerbruch-Str, 17475, Greifswald, Germany.
Ann Hematol. 2012 Jul;91(7):1081-9. doi: 10.1007/s00277-012-1406-5. Epub 2012 Jan 17.
Toxoplasmosis is a rare but possibly underestimated complication following allogeneic stem cell transplantation with a high mortality rate. One reason might be the limitation of the diagnostic instruments relying mainly on imaging and molecular-based techniques. In this report, we present three cases of toxoplasmosis identified among 155 allograft recipients treated at Greifswald University Hospital. Widely disseminated toxoplasmosis was detected post-mortem in two patients allografted for high-risk multiple myeloma. Clinical signs suspicious for toxoplasmosis occurred after days +32 and +75, respectively. In one case, serology and conventional Toxoplasma gondii PCR, targeting the B1 gene, revealed negative results, while in the other patient, toxoplasmosis was not investigated. Both patients received pentamidine for Pneumocystis jirovecii pneumonia (PcP) prophylaxis. The third patient, a 68-year-old woman allografted for AML, developed cerebral toxoplasmosis from day +395 after allogeneic SCT with typical signs in magnetic resonance tomography. Toxoplasma DNA was amplified from one of two samples of cerebrospinal fluid. The patient died of disseminated toxoplasmosis despite immediate initiation of therapy. Retrospective comparative testing of clinical specimens by the conventional T. gondii PCR and by a real-time PCR targeting a 529-bp genomic fragment suggests a higher sensitivity of the latter method in our patients. In conclusion, we suggest a rigorous real-time PCR monitoring for high-risk patients or patients with signs of infections suspicious for toxoplasmosis, even though low-copy results are presently difficult to interpret. Our reported cases might also encourage the use of trimethoprim-sufmethoxazole instead of pentamidine for PcP prophylaxis in those patients.
弓形虫病是异基因造血干细胞移植后一种罕见但可能被低估的并发症，死亡率很高。原因之一可能是诊断仪器的局限性，这些仪器主要依赖于成像和基于分子的技术。在本报告中，我们介绍了在格赖夫斯瓦尔德大学医院接受治疗的 155 名同种异体移植受者中发现的 3 例弓形虫病。两名接受高危多发性骨髓瘤同种异体移植的患者死后均发现广泛播散性弓形虫病。分别在第+32 天和第+75 天出现疑似弓形虫病的临床症状。在一例中，血清学和针对 B1 基因的常规弓形虫 PCR 检测结果均为阴性，而另一名患者未进行弓形虫病检测。两名患者均接受喷他脒预防卡氏肺孢子虫肺炎（PcP）。第三位患者是一名 68 岁女性，因 AML 接受同种异体 SCT，在移植后第+395 天发生脑弓形虫病，磁共振成像显示典型征象。从两份脑脊液样本中的一份中扩增出弓形虫 DNA。尽管立即开始治疗，该患者仍死于播散性弓形虫病。对临床标本进行常规 T. gondii PCR 和针对 529-bp 基因组片段的实时 PCR 回顾性比较检测提示，后一种方法在我们的患者中具有更高的敏感性。总之，我们建议对高危患者或有疑似弓形虫病感染迹象的患者进行严格的实时 PCR 监测，尽管目前低拷贝结果难以解释。我们报告的病例也可能鼓励在这些患者中使用复方磺胺甲噁唑代替喷他脒预防 PcP。
