Lupetti Antonella, Welling Mick M, Mazzi Ulderico, Nibbering Peter H, Pauwels Ernest K J
Department of Infectious Diseases, Leiden University Medical Center, The Netherlands.
Eur J Nucl Med Mol Imaging. 2002 May;29(5):674-9. doi: 10.1007/s00259-001-0760-7. Epub 2002 Mar 6.
The aim of this study was to investigate whether technetium-99m labelled fluconazole can distinguish fungal from bacterial infections. Fluconazole was labelled with (99m)Tc and radiochemical analysis showed less than 5% impurities. The labelling solution was injected into animals with experimental infections. For comparison, we used two peptides for infection detection, i.e. UBI 29-41 and hLF 1-11, and human IgG, all labelled with (99m)Tc. Mice were infected with Candida albicans or injected with heat-killed C. albicans or lipopolysaccharides to induce sterile inflammation. Also, mice were infected with Staphylococcus aureus or Klebsiella pneumoniae. Next, accumulation of (99m)Tc-fluconazole and (99m)Tc-labelled peptides/IgG at affected sites was determined scintigraphically. (99m)Tc-fluconazole detected C. albicans infections (T/NT ratio=3.6+/-0.47) without visualising bacterial infections (T/NT ratio=1.3+/-0.04) or sterile inflammatory processes (heat-killed C. albicans: T/NT ratio=1.3+/-0.2; lipopolysaccharide: T/NT ratio=1.4+/-0.1). C. albicans infections were already seen within the first hour after injection of (99m)Tc-fluconazole (T/NT ratio=3.1+/-0.2). A good correlation (R(2)=0.864; P<0.05) between T/NT ratios for this tracer and the number of viable C. albicans was found. Although (99m)Tc-UBI 29-41 and (99m)Tc-hLF 1-11 were able to distinguish C. albicans infections from sterile inflammatory processes in mice, these (99m)Tc-labelled peptides did not distinguish these fungal infections from bacterial infections. It is concluded that (99m)Tc-fluconazole distinguishes infections with C. albicans from bacterial infections and sterile inflammations.
本研究的目的是调查锝-99m标记的氟康唑能否区分真菌感染与细菌感染。氟康唑用（99m）Tc进行标记，放射化学分析显示杂质少于5%。将标记溶液注入患有实验性感染的动物体内。为作比较，我们使用了两种用于感染检测的肽，即泛素29 - 41和人乳铁蛋白1 - 11，以及均用（99m）Tc标记的人免疫球蛋白。小鼠感染白色念珠菌，或注射热灭活的白色念珠菌或脂多糖以诱导无菌性炎症。此外，小鼠感染金黄色葡萄球菌或肺炎克雷伯菌。接下来，通过闪烁扫描法测定（99m）Tc -氟康唑和（99m）Tc标记的肽/免疫球蛋白在感染部位的蓄积情况。（99m）Tc -氟康唑能检测出白色念珠菌感染（T/NT比值 = 3.6±0.47），而无法显示细菌感染（T/NT比值 = 1.3±0.04）或无菌性炎症过程（热灭活的白色念珠菌：T/NT比值 = 1.3±0.2；脂多糖：T/NT比值 = 1.4±0.1）。在注射（99m）Tc -氟康唑后的第一小时内就能观察到白色念珠菌感染（T/NT比值 = 3.1±0.2）。发现该示踪剂的T/NT比值与白色念珠菌活菌数之间具有良好的相关性（R² = 0.864；P<0.05）。虽然（99m）Tc -泛素29 - 41和（99m）Tc -人乳铁蛋白1 - 11能够区分小鼠白色念珠菌感染与无菌性炎症过程，但这些（99m）Tc标记的肽无法区分这些真菌感染与细菌感染。得出的结论是，（99m）Tc -氟康唑能区分白色念珠菌感染与细菌感染及无菌性炎症。
