Rohlfing M B, Barton T K, Bigner S H, Johnston W W
Acta Cytol. 1981 Nov-Dec;25(6):611-5.
Hematogenous blasts in cytologic preparations of cerebrospinal fluid (CSF) have generally been thought to indicate leukemic involvement of the central nervous system (CNS). However, two leukemic patients who came to autopsy had no CNS involvement despite positive CSF preparations shortly before death. Both patients had over 10,000 blasts/cu mm in their peripheral blood. The CSF specimen from one patient was grossly bloody, but the specimen from the second patient was clear. An experiment was designed to test the hypothesis that membrane filter techniques are sufficiently sensitive to detect blasts in CSF contaminated by amounts of leukemic blood too small to be detected visually. Blood from a leukemic patient with 130,000 cells/cu mm was serially diluted in CSF from 1:20 to 1:1,600,000 and membrane filters from each dilution were examined. No blood could be detected visually at the 1:8,000 and further dilutions. Blasts forms were seen on membrane filter preparations down to the 1:1,600,000 dilution, which contained 0.000000125 ml of blood, equivalent to about 1/40,000th the volume of an 18-gauge spinal needle. These findings suggest that contamination of CSF specimens with minute amounts of blood, undetectable by visual inspection, may lead to erroneous interpretation of leukemic involvement of the CNS.
脑脊液（CSF）细胞学检查中的血源性母细胞通常被认为提示中枢神经系统（CNS）存在白血病浸润。然而，有两名白血病患者在尸检时发现尽管在死亡前不久脑脊液检查呈阳性，但并无CNS浸润。两名患者外周血母细胞计数均超过10,000/立方毫米。其中一名患者的脑脊液标本肉眼可见血性，而另一名患者的标本则清晰。设计了一项实验来检验以下假设：膜过滤技术足够灵敏，能够检测出被少量白血病血液污染的脑脊液中的母细胞，而这些少量血液肉眼无法检测到。将一名白血病患者的血液（细胞计数为130,000/立方毫米）在脑脊液中按1:20至1:1,600,000的比例进行系列稀释，并对每个稀释度的膜滤器进行检查。在1:8,000及更高稀释度下肉眼无法检测到血液。在稀释至1:1,600,000的膜滤器标本上仍可见母细胞形态，该稀释度的标本中含有0.000000125毫升血液，约相当于18号脊髓穿刺针体积的1/40,000。这些发现表明，脑脊液标本被微量血液污染（肉眼检查无法检测到）可能会导致对CNS白血病浸润的错误解读。
