Stanley M W, Mrak R E, Bardales R H
Department of Pathology, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
Diagn Cytopathol. 1995 Oct;13(3):225-8. doi: 10.1002/dc.2840130309.
High magnification examination of Romanovsky-stained bronchoalveolar lavage (BAL) material may be needed, if one is to confidently exclude small organisms such as toxoplasmosis, histoplasmosis, and the negative images of mycobacteria. Pseudomicrobes have been described, and detailed criteria must be carefully applied, if incorrect diagnoses are to be avoided. We recently noted numerous free-lying, uniform, eosinophilic, straight or slightly curved bacilliform structures in such a specimen. These were seen on Diff-Quik-stained material, but were extremely pale on Papanicolaou-stained slides. Comparison with the cilia of contaminating bronchial cells showed these pseudomicrobes to have similar length, diameter, and tinctorial properties. Electron microscopy of the sedimented cell pellet showed isolated, detached single cilia (DSC) far removed from any bronchial cells. Twenty BAL's from 13 males and seven females (median age = 48.5) undergoing infection surveillance were then retrospectively reviewed. DSC were present in 16 specimens (80%), but were rare in three of these. Although present in cases with prominent bronchial cell contamination (n = 6 cases), DSC were also encountered when ciliated cells were rare (n = 13), or absent (n = 1). Familiarity with these distinctive structures should make it unlikely that they will be mistaken for infectious organisms.
如果要可靠地排除诸如弓形虫病、组织胞浆菌病等微生物以及分枝杆菌的阴性影像，可能需要对罗曼诺夫斯基染色的支气管肺泡灌洗（BAL）材料进行高倍镜检查。已描述过假微生物，若要避免错误诊断，必须仔细应用详细标准。我们最近在这样一个标本中发现了许多游离的、形态一致、嗜酸性、直的或略弯曲的杆状结构。这些结构在Diff-Quik染色材料上可见，但在巴氏染色载玻片上颜色极淡。与污染支气管细胞的纤毛比较显示，这些假微生物具有相似的长度、直径和染色特性。对沉淀的细胞团块进行电子显微镜检查发现，有孤立的、脱离的单个纤毛（DSC），与任何支气管细胞相距甚远。然后对13名男性和7名女性（中位年龄 = 48.5岁）接受感染监测的20份BAL样本进行回顾性分析。16份样本（80%）中存在DSC，但其中3份样本中较少见。虽然在支气管细胞污染明显的病例（n = 6例）中存在DSC，但在纤毛细胞稀少（n = 13）或不存在（n = 1）的情况下也能见到DSC。熟悉这些独特结构应可避免将它们误认为感染性生物体。
