Aydın Kaynar Lale, Özkurt Zübeyde Nur, Ülküden Burcu, Güzel Tunçcan Özlem, Aygencel Gülbin, Akyürek Nalan, Kalkancı Ayşe
Gazi University Faculty of Medicine, Department of Hematology, Ankara, Turkey.
Mikrobiyol Bul. 2016 Oct;50(4):613-620.
Saprochaete capitata (formerly known as Geotrichum capitatum and Blastoschizomyces capitatus) is a rare invasive fungal agent that may lead to mortal clinical course in patients with hematological malignancies. This agent can be colonized in skin, lungs and intestines, and it can cause major opportunistic infections. Invasive systemic infections due to S.capitata have been reported in immunosuppressed patients. In this report, two patients with invasive S.capitata infections detected during the course of persistent neutropenic fever in acute leukemia, were presented. In both cases empirical caspofungin was added to the treatment, as no response was obtained by board-spectrum antibacterial therapy in neutropenic fever. In the first patient, there were no significant findings except the chronic inflammation observed in the biopsies which was performed for the symptoms of lymphadenitis, myositis, and hepatosplenic candidiasis. While persistent fever was on going, S.capitata was isolated from the blood and catheter cultures. There was no response after catheter removing and the introduction of amphotericin B and voriconazole therapy, therefore allogeneic stem cell transplantation plan for the second time for bone marrow aplasia was taken an earlier time. However, the patient died due to progressive pericardial and pleural effusion and multiorgan failure, although an afebrile process after stem cell transplantation could be obtained. Similarly the second patient had persistent fever despite empirical caspofungin treatment. The additional symptoms of diarrhea, abdominal pain and subileus have indicated an intraabdominal infection. During the follow up, S.capitata was isolated from the blood and catheter cultures. Catheter was removed and amphotericin B was initiated. No response was obtained, and voriconazole was added to treatment. Despite of an afebrile and culture-negative period, the patient died as a result of Acinetobacter sepsis and multiorgan failure. Minimal inhibitory concentration values for both of the Saprochete strains were found as 0.25 µg/ml for amfoterisin B, 1 µg/ml for flukonazol, 0.125 µg/ml for vorikonazol and 0.25 µg/ml for itrakonazol. Virulence model was created by injecting the isolates to the Galleria mellonella larvae, and the life cycle of the larvae were determined. The observation revealed that the infected larvae began to die on the second day and there was no live larvae remained on the eleventh day. In conclusion, S.capitata should be considered as an infection agent with high mortality risk in the neutropenic patients with hematologic malignancies, especially in the presence of persistent fever during the use of caspofungin.
头状腐质霉(以前称为头状地霉和头状芽裂酵母)是一种罕见的侵袭性真菌病原体,可能导致血液系统恶性肿瘤患者出现致命的临床病程。这种病原体可定植于皮肤、肺部和肠道,并可引起严重的机会性感染。免疫抑制患者中已报告有因头状腐质霉引起的侵袭性全身感染。在本报告中,介绍了两名在急性白血病持续性中性粒细胞减少发热过程中检测出头状腐质霉侵袭性感染的患者。在这两例病例中,由于中性粒细胞减少发热的广谱抗菌治疗无反应,因此在治疗中加用了经验性的卡泊芬净。在第一例患者中,除了因淋巴结炎、肌炎和肝脾念珠菌病症状进行活检时观察到的慢性炎症外,没有其他显著发现。在持续发热期间,从血液和导管培养物中分离出头状腐质霉。拔除导管并引入两性霉素B和伏立康唑治疗后无反应,因此提前进行了第二次异基因干细胞移植计划以治疗骨髓再生障碍。然而,尽管干细胞移植后可获得无热过程,但患者因进行性心包和胸腔积液及多器官功能衰竭死亡。同样,第二例患者在经验性使用卡泊芬净治疗后仍持续发热。腹泻、腹痛和肠梗阻等附加症状提示存在腹腔内感染。在随访过程中,从血液和导管培养物中分离出头状腐质霉。拔除导管并开始使用两性霉素B。无反应,随后加用伏立康唑治疗。尽管有一段无热且培养阴性的时期,但患者因不动杆菌败血症和多器官功能衰竭死亡。两种头状腐质霉菌株的最小抑菌浓度值分别为:两性霉素B为0.25μg/ml,氟康唑为1μg/ml,伏立康唑为0.125μg/ml,伊曲康唑为0.25μg/ml。通过将分离株注射到黄粉虫幼虫中建立毒力模型,并确定幼虫的生命周期。观察发现,感染的幼虫在第二天开始死亡,到第十一天没有存活的幼虫。总之,在血液系统恶性肿瘤的中性粒细胞减少患者中,尤其是在使用卡泊芬净期间出现持续发热的情况下,头状腐质霉应被视为一种具有高死亡风险的感染病原体。