Differentiation of Enterobacteriaceae, Pseudomonas aeruginosa, and Bacteroides and Haemophilus species in gram-stained direct smears.

The accuracy of examination of the Gram-stained direct smear to classify presumptively Gram-negative rods into three morphotype groups, that is, (a) Enteric bacteria, (b) Pseudomonas, and (c) Bacteroides or Haemophilus, was evaluated. Randomly selected clinical strains (4-9) each of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Ps. aeruginosa, B. fragilis, and H. influenzae were used to produce peritonitis or subcutaneous abscesses in mice. A Gram-stained direct smear was prepared from exudate collected from each animal. The direct smears were examined to classify bacteria observed into one of the three morphotype groups. The percent accuracy was 82, 56, and 95, respectively, and 76 overall. The assumption was made that classification was based primarily on differences in length and width of the organisms. To test this hypothesis, we prepared scanning electron photomicrographs from each specimen of exudate and measured the lengths and widths of bacteria. Examination of the Gram-stained direct smear was more accurate for classification of enteric bacteria, H. influenzae, or B. fragilis. Electron microscopy was more accurate for classification of Ps. aeruginosa. The higher length-width radio should be helpful in recognizing Ps. aeruginosa in direct smears.     

The microbiology of bacteriuria in men: a 5-year study at a Veterans' Affairs hospital

Bacteriuria and urinary tract infection occur relatively frequently in older men, but data regarding the causative microorganisms are limited. We retrospectively identified all positive cultures of urine specimens (n = 4943) obtained over a 5-year period at our institution. We determined the frequency of causative microorganisms and grouped these by Gram type, setting of patient care, and method of urine specimen collection. We also assessed the performance characteristics of the Gram-stained smear of uncentrifuged urine. Among our patients, Gram-positive cocci (GPC) were isolated as often as Gram-negative rods (GNR). Escherichia coli was the single or predominant isolate in only 14% of cases, and Enterococcus was the single most commonly identified genus (22.5%). The Gram stain was accurate in predicting the culture results (positive likelihood ratio, 7.0 for GPC and 8.1 for GNR). We conclude that the microorganisms causing bacteriuria in older male veterans are substantially different from those found in women, and the Gram-stained smear provides useful information on the causative organisms.     

Nonspecific vaginitis and Gardnerella vaginalis: methodological and epidemiological notes on 328 cases

328 samples of vaginal discharges in adult fertile women, aged between 16 and 48, were examined in this trial. After excluding 95 women (39 were affected by vaginal Trichomoniasis, 55 whose discharge presented yeasts and 1 affected by gonococcal infection), the authors divided the remaining 233 cases into subjects affected or not affected by nonspecific vaginitis (NSV) only using a Gram-stained smear. In the 83 patients affected by NSV, the authors isolated Gardnerella vaginalis in the 90.4% of the cases. After statistically correlating the different parameters described in literature as associated to NSV (pH, KOH-test, Clue Cells, isolation of G. vaginalis, symptoms), the authors concluded that: a) Gram-stained smear may be used as a simple microscopical test for diagnosis, in most of the cases, NSV; b) in most of the cases of NSV are implicated more organisms (essentially G. vaginalis and anaerobic organisms); c) G. vaginalis can be considered as a marker of these infections.     

Performance of a rapid yeast test in detecting Candida spp. in the vagina

We compared the performance of a rapid vaginal yeast assay (Savvycheck) with that of microscopic examination of a Gram-stained smear and culture of vaginal discharge in detecting Candida spp. Two hundred thirty-one women with vaginal symptoms were studied prospectively. Vaginal specimens obtained from all participants were studied by the Savvycheck rapid yeast test, microscopic evaluation of Gram-stained vaginal smears, and yeast culture. Savvycheck rapid yeast test was positive in 79% of women with positive cultures and in 3.6% of women with negative cultures. The Savvycheck test detected yeasts in 93% of subjects with positive Gram stain and in 5.5% of subjects with negative Gram stain. The Savvycheck rapid yeast test showed 93% sensitivity, 95% specificity, and a 97% negative predictive value compared with the Gram stain. It revealed 79% sensitivity, 96% specificity, and an 87% negative predictive value compared with culture. The Savvycheck rapid yeast test can be used in the busy office instead of microscopy as a point-of-care tool for diagnosing vulvovaginal candidiasis. It can also reduce the need for yeast cultures in patients with vaginitis.     

Effect of including recommendations for antimicrobial therapy in microbiology laboratory reports

Innovative approaches are needed to improve cost-effective antibiotic use in hospitals. We established an algorithm to provide a recommendation for both a single oral and a single parenteral antimicrobic, including dosage, to be placed in the bacteriology laboratory report for therapy guidance of 174 episodes of lower respiratory infection in a group of "program" patients with no evidence of infection at other sites. The initial recommendation was based on the Gram-stained direct smear of secretions. The recommendation was updated when preliminary culture results were available, and again with final identification and susceptibility data. We compared the severity of illness, length of stay, and cost of therapy for 68 episodes in program patients who received the recommended therapy with 111 episodes in a control group of patients who received antimicrobial therapy but for whom no recommendations were reported. There was a significantly greater use of the recommendations for sicker patients. Antimicrobial therapy, in general, was more often used for the program patients than for the controls. There was no difference in length of stay or therapy cost. We recommend that this approach be used in settings where there is more problematic use of antimicrobics.     

BACTERIAL VAGINOSIS

SUMMARY Bacterial vaginosis (BV) is an alteration of the vaginal flora, where the normally predominant lactobacilli are replaced by a cocktail of organisms including Gardnerella vaginalis and anaerobes. It presents with a grey, homogenous, offensive vaginal discharge that has a raised pH. However, around half the women with this condition are asymptomatic. Diagnosis is best made by microscopic examination of a Gram-stained smear of vaginal secretions. Treatment is with metronidazole or clindamycin. The indications for treatment of asymptomatic BV are not clear, but women should probably be treated before any invasive gynaecological procedure, including intrauterine contraceptive device (IUCD) insertion. BV during pregnancy is associated with preterm labour, although a causal effect is not proven; studies are in progress to determine whether treatment of BV will improve the outcome of these pregnancies.     

革兰染色痰涂片镜检与痰培养的荟萃分析

目的:综合分析革兰染色痰涂片镜检的临床应用价值。方法:应用荟萃分析(meta-analysis)对国内6组(共3210例)痰涂片革兰染色镜检结果及痰培养结果随机对照分析,评价革兰染色痰涂片镜检的临床应用价值。结果:共有6篇纳入研究,包括3210例,其中3030例为检索相关文献,180例为现收集标本。分析表明,革兰染色痰涂片镜检结果具较重要的临床价值,与临床诊断结果密切相关。结论:应提倡进行革兰染色痰涂片镜检。     

200例产后妇女阴道微生态状况分析

目的探讨产后女性阴道微生态状况。方法选择本院产后门诊复查的产后妇女200例及来本院妇科体检的健康妇女40例,采集阴道分泌物,测定pH值,并用革兰氏染色涂片后采用Nugent评分进行阴道微生态学评价及比较。结果200例产后妇女阴道pH值为（4．66±0．25）;微生态正常者9例,占4．5％;阴道微生态失调191例,占95．5％;乳杆菌检出率14．5％。40例健康妇女阴道pH值为（4．25±0．35）;阴道微生态正常者31例,占77．5％;阴道微生态失调9例,占22．5％;乳杆菌检查率82．5％。差异有统计学意义。结论产后妇女阴道微生态发生改变,表现为pH升高,微生态失调比例明显升高,应引起关注。     

Use of lactophenol cotton blue mounts of corneal scrapings as an aid to the diagnosis of mycotic keratitis.

Lactophenol cotton blue (LPCB) mounts of corneal ulcer scrapings were assessed as a diagnostic tool in cases of mycotic keratitis over a period of 15 months. We investigated 568 cases of ulcerative keratitis by microbiological techniques consisting of direct microscopic examination of LPCB mounts and Gram-stained smears as well as culture of material scraped from the ulcer. Fungi were isolated in large numbers on multiple media from the corneal scrapings of 179 patients (culture-proven mycotic keratitis). Direct microscopic examination of LPCB mounts of corneal scrapings yielded positive results in 140 (78%) of 179 culture-positive patients and negative results in 371 (95%) of 389 culture-negative patients. There was a significant difference between the percentage of positive results obtained by LPCB mounts and by Gram-stained smears in the culture-positive cases. The LPCB mount was positive in greater than 80% of cases of keratitis due to Fusarium spp. and Aspergillus spp. The LPCB mount is strongly recommended as a simple, rapid, inexpensive, and sensitive diagnostic technique in cases of mycotic keratitis.     

Differentiation of Pseudomonas aeruginosa and Enterobacteriaceae in direct smears based on measurements by scanning electron microscopy

We believe that experienced observers can often distinguish between Enterobacteriaceae and Pseudomonas aeruginosa, by differences in dimensions in Gram-stained direct smears. Many microbiologists question whether this should be attempted because of overlap in dimensions. We have found that culture results confirm our observations about 80% of the time and that such reporting is helpful in diagnosis and treatment. We decided to try to verify the differences in dimensions objectively. Because of the limitations of making measurements by light microscopy, exudate from clinical specimens and from experimental mouse infections were examined by scanning electron microscopy. Discriminant function analysis was applied to the dimensions of length and width, and this showed that 83% of the organisms in both groups could be correctly classified on the basis of the dimensions. This supports our premise that experienced observers should be able to differentiate between these organisms in Gram-stained direct smears, using light microscopy with sufficient confidence to provide clinically useful information.     

血涂片复审人员资历及效率的比较

目的探讨血涂片复审人员资历及效率。方法选择不同资历技术人员在显微镜下观察各类血涂片,分别记录检测数据和分析时间,并进行比较分析。结果各类人员对成熟中性粒细胞、嗜酸粒细胞、淋巴细胞和单核细胞的检测数据均无显著性差异;未经血液学检验培训者对于幼稚粒细胞分辨能力较差,并可影响单核细胞的识别;而对于白血病细胞类型的鉴定,只有血细胞形态学专业技术人员才能准确完成。血涂片复审时间与WBC值未呈特定的相关关系,形态学工作者平均观察用时约10min,明显少于其他人员。结论血液细胞形态学专业技术人员能完全胜任血涂片的复审工作;长期从事基础检验专业者或经过血液学实验室训练后的年轻技师可承担血涂片“筛查”或“核实”工作;而未从事基础检验和血液学检验者或未经血液学实验训练的基础检验年轻技师,不能从事本项工作。同时血涂片复审耗时长、劳动强度大,合理安排人员、建立适当程序有利于提高检验效率。     

Usefulness of gram-stained sputum obtained just after administration of antimicrobial agents as the earliest therapeutic indicator for evaluating the effectiveness of empiric therapy in community-acquired pneumonia caused by pneumococcus or Moraxella catarrhalis

We present here three cases in which morphological changes and/or a decreased number of Streptococcus pneumoniae or Moraxella catarrhalis could be observed in gram-stained sputum obtained just after the first administration of an antimicrobial agent. Case 1 was a 53-year-old man with pneumonia caused by gram-positive diplococcus, identified as S. pneumoniae, who was administered 2 g of ampicillin over a period of 1 h. Gram-stained sputum showed smaller or gram-negative pneumococci at the completion of administration of the agent, a decreased number of cocci at 1 h after administration, and almost no cocci at 12 h after the completion of administration. Case 2 was a 72-year-old woman with pneumonia caused by diplococcus, identified as S. pneumoniae, who was administered 2 g of ampicillin over a period of 1 h. Gram-stained sputum showed weakly stained, small cocci at the completion of administration of the agent and few cocci at 1 h after the completion of administration. Case 3 was a 58-year-old woman with pneumonia caused by a gram-negative diplococcus, identified as Moraxella catarrhalis, who was administered 1 g of cefotaxime over a period of 30 min. Gram-stained sputum showed few extracellular cocci and some intracellular cocci inside neutrophils 1 h after administration and no cocci 2 h after the completion of administration. These three cases showed that gram-stained sputum obtained just after and/or 1 h after administration of the first antimicrobial agent were suitable as the quickest therapeutic indicator of the effectiveness of empiric therapy, with the effectiveness of the agent being shown much earlier than with markers such as the white blood cell count and C-reactive protein level.     

血涂片复检在采用仪器法测定结果可靠性评估中的价值

目的探讨血细胞涂片复检在采用仪器法分析复查中的必要性和可靠性,强调手工涂片复检的重要性。方法采用仪器法对随机抽查的746例标本结果进行筛查,并严格按照血涂片制备方法和细胞形态学分类方法对筛查的结果进行手工复检,复检原则参照国际血细胞复检规则相关条款。结果根据复检规则对检测结果进行统计学分析,得到真阳性率为4.6%,假阳性率为20.4%,真阴性率为74.0%,假阴性率为1.1%,复检率为25%。仪器法测定的敏感度为28.8%,特异度为98.6%,阳性预测值为81.0%,阴性预测值为78.4%,准确性为78.6%。结论血细胞形态学检查在血常规分析中具有十分重要的意义,仪器法检测的方法学具有其局限性,对于形态、结构异常的细胞不能作出准确判断和定位,一旦仪器检测提示异常,应及时涂片镜检复查,以保证检验结果的准确性和可靠性。     

自动化镜检结合人工智能分析系统对阴道分泌物革兰氏染色涂片形态学的准确性评价

目的 探究自动化镜检结合人工智能分析系统对阴道分泌物革兰氏染色涂片阴道微生态形态学评价的准确性.方法 收集2020年1—5月北京协和医院妇产科门诊患者的阴道分泌物标本.标本经涂片、革兰氏染色,分别进行人工镜检和自动化镜检.自动化镜检采用仕达思Comet-60au高倍镜检分析系统,并通过人工智能分析自动判定结果.对形态学...     

骨髓活检在血液病诊断中的临床应用研究

目的通过骨髓涂片与骨髓切片比较,明确骨髓活检在血液病诊断中的重要作用。方法对138例血液病患者分别进行骨髓穿刺与骨髓活检,观察骨髓涂片与骨髓切片结果。结果骨髓切片能较准确地反映骨髓的增生程度,在骨髓异常增生综合征(MDS)、淋巴瘤、骨髓纤维化(MF)、急性白血病(AL)诊断中明显优于骨髓涂片。结论骨髓活检切片在某些血液病诊断上优于骨髓涂片,2者相结合,可有效提高血液病临床上的诊断水平。     

结核分枝杆菌检测方法临床应用的对比研究

目的用涂片、聚合酶链反应(PCR)法检测结核分枝杆菌,探讨其临床应用价值。方法对169例临床确诊的肺结核患者、可疑肺结核患者和非结核患者痰标本用涂片、PCR两种方法进行检测,对结果进行对比分析。结果 169例痰标本中,痰涂片检查阳性率为7.1%(12/169),PCR检测阳性率为32.54%(55/169);痰涂片、PCR法检测42例临床确诊的肺结核患者痰标本阳性率分别为11.9%(5/42)、57.1%(24/42);检测82例临床可疑肺结核患者痰标本阳性率分别为8.54%(7/82)、37.8%(31/82)。比较两种方法的阳性检测率,差异有统计学意义(χ2=19.729,P<0.01),检测45例非结核患者痰标本,涂片及PCR检测均为阴性。结论 PCR法检测结核分枝杆菌具有较高的敏感性和特异性,可作为临床结核病检测诊断的有效方法之一。     

骨髓涂片荧光原位杂交法在检测多发性骨髓瘤细胞8号染色体遗传学异常的应用

本研究旨在建立骨髓涂片间期荧光原位杂交（I-FISH）的实验方法,为检测多发性骨髓瘤（MM）分子细胞遗传学提供新方法。以骨髓涂片为载体,通过一系列的处理,固定及消化后,用8号染色体着丝粒探针行I-FISH分子细胞遗传学的检测,并比较该方法与常规I-FISH结果的差异。结果表明：两种方法分析非恶性血液病标本的各个信号比例无统计学差异（P〉0．05）。骨髓涂片I-FISH研究中,19例MM患者中8例（42．1％）有8号染色体异常,其中8号染色体单体（-8）5例（26．3％）,8号染色体三倍体（＋8）3例（15．8％）。结论：骨髓涂片I-FISH具有操作简便、经济、准确的特点,可用于MM分子遗传学异常的研究。     

骨髓涂片免疫组化在形态学难以诊断的急性白血病中的临床研究

目的 分析骨髓涂片免疫组化在急性白血病中的诊断价值.方法 采用骨髓涂片免疫组化,对40例形态学难以诊断的急性白血病进行免疫表型分析,与单独用形态学诊断的结果比对,对两种结果进行一致性检验有差异的与流式细胞仪分型对照.结果 骨髓涂片免疫组化的结果和FCM有较好的一致性,采用免疫表型分析的结果为临床诊断和预后提供了更有力的帮助,对M0和MAL的诊断有决定性的意义,较形态学诊断的结果更好.结论 骨髓涂片免疫组化在形态学难以诊断的急性白血病分型中有较好的临床价值,能更好地进一步分型.     

骨髓涂片免疫组化在形态学难以诊断的急性白血病中的临床研究

目的 分析骨髓涂片免疫组化在急性白血病中的诊断价值.方法 采用骨髓涂片免疫组化,对40例形态学难以诊断的急性白血病进行免疫表型分析,与单独用形态学诊断的结果比对,对两种结果进行一致性检验有差异的与流式细胞仪分型对照.结果 骨髓涂片免疫组化的结果和FCM有较好的一致性,采用免疫表型分析的结果为临床诊断和预后提供了更有力的帮助,对M0和MAL的诊断有决定性的意义,较形态学诊断的结果更好.结论 骨髓涂片免疫组化在形态学难以诊断的急性白血病分型中有较好的临床价值,能更好地进一步分型.     

骨髓涂片免疫组化在形态学难以诊断的急性白血病中的临床研究

目的 分析骨髓涂片免疫组化在急性白血病中的诊断价值.方法 采用骨髓涂片免疫组化,对40例形态学难以诊断的急性白血病进行免疫表型分析,与单独用形态学诊断的结果比对,对两种结果进行一致性检验有差异的与流式细胞仪分型对照.结果 骨髓涂片免疫组化的结果和FCM有较好的一致性,采用免疫表型分析的结果为临床诊断和预后提供了更有力的帮助,对M0和MAL的诊断有决定性的意义,较形态学诊断的结果更好.结论 骨髓涂片免疫组化在形态学难以诊断的急性白血病分型中有较好的临床价值,能更好地进一步分型.