Ostergaard L, Nielsen A K, Black F T
Department of Infectious Diseases, Marselisborg Hospital, Aarhus, Denmark.
Scand J Infect Dis. 1993;25(2):227-37. doi: 10.3109/00365549309008489.
Reactivation of Toxoplasma gondii can lead to a life-threatening intracerebral infection in immunocompromised HIV-positive patients. Due to the current diagnostic limitations for establishing an exact diagnosis of cerebral toxoplasmosis, a nested PCR system was developed for direct detection of T. gondii in cerebrospinal fluid. A storage temperature for samples of -20 degrees C and sample preparation using Proteinase K appeared to be critical for obtaining a high sensitivity of PCR. A total of 56 samples from 38 HIV-positive patients and 12 HIV-negative patients with symptoms or signs of neurological disease were evaluated by PCR. 5 of the 38 HIV-positive patients were diagnosed as having cerebral toxoplasmosis and PCR was positive in samples from all 5 patients. In the remaining 33, PCR was positive in one case and negative in 32. An exact etiological diagnosis other than cerebral toxoplasmosis was established in 5 patients. PCR performed on cerebrospinal fluid samples seems to be a fast, sensitive, specific and valuable tool for establishing the diagnosis of cerebral toxoplasmosis among HIV-positive patients at the time of presentation of symptoms or signs of neurological disease.
弓形虫再激活可导致免疫功能低下的HIV阳性患者发生危及生命的脑内感染。由于目前在准确诊断脑弓形虫病方面存在诊断局限性，因此开发了一种巢式PCR系统，用于直接检测脑脊液中的弓形虫。样本-20℃的储存温度以及使用蛋白酶K进行样本制备似乎对于获得高灵敏度的PCR至关重要。通过PCR对38例HIV阳性患者和12例有神经疾病症状或体征的HIV阴性患者的共56份样本进行了评估。38例HIV阳性患者中有5例被诊断为脑弓形虫病，所有5例患者的样本PCR均呈阳性。其余33例中，1例PCR呈阳性，32例呈阴性。5例患者确诊为除脑弓形虫病以外的确切病因。对脑脊液样本进行PCR检测似乎是一种快速、灵敏、特异且有价值的工具，可用于在出现神经疾病症状或体征时对HIV阳性患者进行脑弓形虫病的诊断。
