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1.
The mechanical pressure exerted during centrifugation and the chemical pressure experienced when sputum specimens are processed, leave the tubercle bacilli in the sputum unsuitable for rapid detection especially in phage based assays. Thus, growing Mycobacterium tuberculosis in broth, at least overnight, is mandatory for allowing the tubercle bacilli to recoup. During this time the surviving colonizing flora grow faster and overgrow tubercle bacilli interfering with TB diagnosis. In the present study normal flora surviving the action of 4% NaOH was isolated and characterized. Phages capable of killing 14 different species representing this normal flora were isolated from soil and sewage samples and characterized. A novel and bio-friendly approach to treat sputum samples with a cocktail of three phages capable of killing most of the 14 representative organisms and not infecting mycobacteria is explored to control the overgrowth of colonizing bacteria in broth culture. While 26 of the 100 sputum samples processed by modified Petroff's procedure showed growth of colonizing flora on blood agar, all of them when grown in broth overnight showed mixed, confluent growth. The addition of phagebiotics controlled them all, showing a significant reduction in colony forming units but resulting in few discrete colonies in 54 samples. Isolation of phages capable of controlling these surviving organisms and including them in the phagebiotics mixture should lead to the control of colonizing bacteria effectively.  相似文献   

2.
Quantitation of Microorganisms in Sputum   总被引:11,自引:0,他引:11       下载免费PDF全文
A method of quantitating microbial cultures of homogenized sputum has been devised. Possible application of this method to the problem of determining the etiologic agent of lower-respiratory-tract infections has been studied to determine its usefulness as a guide in the management of these infections. Specimens were liquefied by using an equal volume of 2% N-acetyl-L-cysteine. The liquefied sputum suspension was serially diluted to 10-1, 10-3, 10-5, and 10-7. These dilutions were plated on appropriate media by using an 0.01-ml calibrated loop; they were incubated and examined by standard diagnostic methods. Quantitation of fresh sputum from patients with pneumonia prior to antimicrobial therapy revealed that probable pathogens were present in populations of 107 organisms/ml or greater. Normal oropharyngeal flora did not occur in these numbers before therapy. Comparison of microbial counts on fresh and aged sputum showed that it is necessary to use only fresh specimens, since multiplication or death alters both quantitative and qualitative findings. Proper collection and quantitative culturing of homogenized sputum provided information more directly applicable to patient management than did qualitative routine methods. Not only was the recognition of the probable pathogenic organism in pneumonia patients improved, but serial quantitative cultures were particularly useful in recognizing the emergence of superinfections and in evaluating the efficacy of antimicrobial therapy.  相似文献   

3.
In view of the wide-spread existence of legionellae in cooling-tower and other environmental water, asymptomatic infection of this organism could occur. In order to verify the possibility of colonization of legionellae at lower respiratory tract of patients with various pulmonary diseases, a total of 22,036 sputum samples from in- and out-patients at National Sanyoso Hospital were examined during a five-year period from September, 1984 to August, 1989. Four (0.073%) out of 5,502 cases were culture-positive for L. pneumophila. L. pneumophila strains were isolated from expectorated, subsequently washed sputum samples of two male and two female patients with respiratory tract diseases. The identification of the isolates was genetically confirmed by the fluorometric microplate DNA-DNA hybridization method. The serogroup (SG) and viable counts of L. pneumophila per ml of sputum of each patient were as follows: 73 y/o female K.H., SG-6, 10(3) CFU; 75 y/o male H.J., SG-5, 10(4) CFU; 61 y/o female M.S., SG-5, 10(5) CFU; and 77 y/o male M.G., not-agglutinable against SG-1-6 antisera, 10(4) CFU. None of the four patients was clinically suspected of legionellosis and antibody titer of paired sera remained 1:64 or lower than 1:32. From these findings, we concluded that L. pneumophila can cause, though quite rarely, asymptomatic infection in human respiratory tract. None of the environmental samples obtained from in- and out-side of the Hospital was culture-positive for legionellae. Thus, the source of infection has remained unknown.  相似文献   

4.
This study is a quantitative comparison of the sputum produced by 12 subjects with cystic fibrosis (CF) who received high-frequency chest compression (HFCC) and standard chest physical therapy (CPT) in randomized order. Six subjects routinely used manual CPT and six routinely used the HFCC. None had acute infections or hospitalization in the six weeks before the study. Two certified respiratory therapists alternated subjects and CPT vs HFCC order during the two weeks of the matched study. For all sessions, the expectorated sputum was collected in preweighed cups, which were reweighed immediately after collection and again after evaporation to dryness. The wet and dry weights of the sputum produced as a result of the two techniques were significantly different, with HFCC having greater weight. Regardless of the mode of therapy, the sputum produced by the subjects who regularly received HFCC had greater water content than did the sputum produced by those subjects who regularly received CPT. No significant difference was found between the two therapists regarding sputum expectorated by the subjects during CPT. These results show that sputum production by subjects with CF who receive CPT by certified respiratory therapists can be as great as the sputum produced by the same subjects who receive HFCC. The results also suggest that unknown factors attributed to the therapists may produce different levels of effort from time to time that may decrease the respiratory therapists' effectiveness, whereas the HFCC therapy may be more consistently effective because it is entirely machine based.  相似文献   

5.
To complement donor selection and tissue processing, rapid and reliable detection, discrimination, and quantification of fungal pathogens are extremely important for tissues destined to be implanted into humans. The current detection method for fungal pathogens, in particular, is difficult and time-consuming. Quantitative polymerase chain reaction (qPCR) technology is considered one of the most sensitive methods to detect low levels of DNA. Here a qPCR method is described that can detect clinically relevant, pathogenic fungal organisms. The assay allowed the quantification of fungal organisms within a tissue implant and provides a means to identify the contaminating species. The primers for the qPCR assay were designed to amplify a conserved region of the L2 region of the large ribosomal subunit (LSU) gene. This set of primers was able to detect fewer than 10 colony forming units from Aspergillus and Candida species in spiked samples. Clinical samples were also evaluated using this method and the data compared positively to the existing accepted 28-day fungal culture method for fungal detection. The qPCR method described herein significantly reduced the time required to identify fungal contamination in tissue implants.  相似文献   

6.
D Qin 《Acta cytologica》1986,30(5):547-548
Neostigmine induction was investigated as a method for increasing the rate of detection of lung cancer in respiratory cytology samples. Eleven patients with dry and essentially nonproductive cough were given neostigmine, 15 mg by mouth or 0.5 mg by hypodermic injection. The quality of sputum produced was increased in all cases; the sputum was also more easily expectorated. Eight patients suspected of having lung cancer had previously negative cytologic examinations of sputum obtained by conventional methods. Following the administration of neostigmine, malignant cells indicating squamous-cell carcinoma were found in the sputum samples of three of these patients while dysplastic cells were detected in the samples from two patients. It is postulated that neostigmine intake may increase the excretion of mucous glands in the bronchial submucosa as well as the bronchial epithelium itself.  相似文献   

7.
8.
In order to evaluate the predictive value of acid fast bacilii (AFB) smear for the diagnosis of Mycobacterium tuberculosis in respiratory specimens in a setting with a high prevalence of AIDS and an unknown prevalence of nontuberculous mycobacteria (NTM), we retrospectively examined specimens cultured for mycobacteria between 1 September 1993 and 30 September 1994 and medical records of patients with positive culture in a General Hospital, AIDS reference in Rio de Janeiro, Brazil. Seventy three per cent (1517/2077) of samples were respiratory specimens and mycobacteria were recovered from 20.6% (313/1517) of these. M. tuberculosis was identified in 94.2% (295/313) and NTM in 5.8% (18/313). The yield of positive AFB smear and of positive culture was 6.1% (93/1517) and 20.6% (313/1517), respectively. The positive predictive value (PPV) of AFB for M. tuberculosis was 98.4% in expectorated sputum and 96.4% in bronchoalveolar lavage. Forty four percent (130/295) of specimens with positive culture for M. tuberculosis and 66.7% (12/18) for NTM were from patients HIV positive. The conclusion was that in our study population, the PPV of AFB for M. tuberculosis in respiratory specimens was high and the prevalence of NTM was low despite the high prevalence of HIV positive.  相似文献   

9.
目的了解重症监护室(ICU)开放气道患者下呼吸道感染病原菌分布及耐药特点,为临床用药提供依据。方法回顾性分析2007年1月至2008年12月,重症监护室开放气道患者下呼吸道感染者的痰标本418株病原菌进行鉴定及药敏试验。结果革兰阴性杆菌占69.6%,其中铜绿假单胞菌27.02%,其次为鲍曼不动杆菌20.16%。革兰阳性球菌占20.16%,以金黄色葡萄球菌为主占12.5%,真菌10.24%。结论目前重症监护室下呼吸道致病菌以G^-杆菌为主,细菌的耐药性严重,应根据药敏试验选择抗生素。  相似文献   

10.
Kang Y  Deng R  Wang C  Deng T  Peng P  Cheng X  Wang G  Qian M  Gao H  Han B  Chen Y  Hu Y  Geng R  Hu C  Zhang W  Yang J  Wan H  Yu Q  Wei L  Li J  Tian G  Wang Q  Hu K  Wang S  Wang R  Du J  He B  Ma J  Zhong X  Mu L  Cai S  Zhu X  Xing W  Yu J  Deng M  Gao Z 《PloS one》2012,7(6):e38743
Etiologic diagnoses of lower respiratory tract infections (LRTI) have been relying primarily on bacterial cultures that often fail to return useful results in time. Although DNA-based assays are more sensitive than bacterial cultures in detecting pathogens, the molecular results are often inconsistent and challenged by doubts on false positives, such as those due to system- and environment-derived contaminations. Here we report a nationwide cohort study on 2986 suspected LRTI patients across P. R. China. We compared the performance of a DNA-based assay qLAMP (quantitative Loop-mediated isothermal AMPlification) with that of standard bacterial cultures in detecting a panel of eight common respiratory bacterial pathogens from sputum samples. Our qLAMP assay detects the panel of pathogens in 1047(69.28%) patients from 1533 qualified patients at the end. We found that the bacterial titer quantified based on qLAMP is a predictor of probability that the bacterium in the sample can be detected in culture assay. The relatedness of the two assays fits a logistic regression curve. We used a piecewise linear function to define breakpoints where latent pathogen abruptly change its competitive relationship with others in the panel. These breakpoints, where pathogens start to propagate abnormally, are used as cutoffs to eliminate the influence of contaminations from normal flora. With help of the cutoffs derived from statistical analysis, we are able to identify causative pathogens in 750 (48.92%) patients from qualified patients. In conclusion, qLAMP is a reliable method in quantifying bacterial titer. Despite the fact that there are always latent bacteria contaminated in sputum samples, we can identify causative pathogens based on cutoffs derived from statistical analysis of competitive relationship. TRIAL REGISTRATION: ClinicalTrials.gov NCT00567827.  相似文献   

11.

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.  相似文献   

12.

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.  相似文献   

13.
We investigated the interleukin-8 (IL-8) levels and neutrophil numbers in the sputum of 9 elderly patients with lower respiratory tract infections, including Pseudomonas aeruginosa infection, before and after treatment with various antimicrobial agents. The IL-8 levels in sputum supernatants and the neutrophil numbers in sputum smears from 9 patients decreased significantly after the elimination of the causative respiratory pathogens. We also demonstrated that human recombinant IL-8 at a range of 6.25-25 ng/ml significantly enhanced opsonophagocytic killing of P. aeruginosa immunotype-1 strain by human neutrophils in the presence of a serotype-specific anti-lipopolysaccharide monoclonal antibody and fresh normal human serum. These data suggest that the level of IL-8 production in the airways of patients with lower respiratory tract infections is dependent on bacterial densities, and indicate the important role of IL-8 not only in neutrophil migration but also in opsonophagocytic killing of bacteria in the lower respiratory tract.  相似文献   

14.
The effect of thermal injury on the host response to systemic infections withCandida albicans was studied by use of a 20% total body surface, full-thickness scald burn in inbred BALB/c mice. The lethal dose of intravenously injectedC. albicans required to kill 50% of the population (LD50) of control, sham-burned mice was 4.7×105 organisms, whereas the LD50 of burned mice was 300 organisms (p<0.001). Mice injected intraperitoneally with 2×107 C. albicans were assayed at two, four, seven, and ten days after burn for the presence of yeasts in the kidneys, skin, or burn wounds. At each time period examined, fewer yeasts were recovered from the kidneys of sham-burned mice than from burned mice. In addition, only one (5%) of 20 sham-burned mice had organisms in the skin at the time of sacrifice, whereas seven (37%) of 19 burned mice had organisms isolated from the burn wound (p<0.05). Wound histology demonstrated that the organisms were localized in the subeschar area and not colonizing the wound surface. This study describes the enhanced susceptibility of burned mice to systemic candidiasis and shows that a systemic infection withCandida can lead to organisms contaminating the wound.  相似文献   

15.
The present study analysed the concordance among four different molecular diagnostic methods for tuberculosis (TB) in pulmonary and blood samples from immunocompromised patients. A total of 165 blood and 194 sputum samples were collected from 181 human immunodeficiency virus (HIV)-infected patients with upper respiratory complaints, regardless of suspicious for TB. The samples were submitted for smear microscopy, culture and molecular tests: a laboratory-developed conventional polymerase chain reaction (PCR) and real-time quantitative PCR (qPCR) and the Gen-Probe and Detect-TB Ampligenix kits. The samples were handled blindly by all the technicians involved, from sample processing to results analysis. For sputum, the sensitivity and specificity were 100% and 96.7% for qPCR, 81.8% and 94.5% for Gen-Probe and 100% and 66.3% for Detect-TB, respectively. qPCR presented the best concordance with sputum culture [kappa (k) = 0.864)], followed by Gen-Probe (k = 0.682). For blood samples, qPCR showed 100% sensitivity and 92.3% specificity, with a substantial correlation with sputum culture (k = 0.754) and with the qPCR results obtained from sputum of the corresponding patient (k = 0.630). Conventional PCR demonstrated the worst results for sputa and blood, with a sensitivity of 100% vs. 88.9% and a specificity of 46.3% vs. 32%, respectively. Commercial or laboratory-developed molecular assays can overcome the difficulties in the diagnosis of TB in paucibacillary patients using conventional methods available in most laboratories.  相似文献   

16.
PurposeAn adaptive concomitant boost (ACB) for the neo-adjuvant treatment of rectal cancer was clinically implemented. In this study population margins M(90,90) considering rectal deformation were derived for 10 consecutive patients treated at 18 × 2.3 Gy with Helical Tomotherapy (HT) and prospectively validated on 20 additional patients treated with HT, delivering ACB in the last 6 fractions.MethodsSectorial margins M(90,90) of the whole and second treatment parts were assessed for 90% population through a method combining the 90% coverage probability maps of rectal positions (CPC90%) with 3D local distance measurements between the CPC90% and a reference rectal contour. M(90,90) were compared with the margins M(90,90)95%/99%, ensuring CPC90% coverage with 95%/99% confidence level. M(90,90) of the treatment second part were chosen as ACB margins which were clinically validated for each patient by means of %volume missing of CPC5/6 excluded by the ACB margins.ResultsThe whole treatment M(90,90) ranged between 1.9 mm and 9 mm in the lower-posterior and upper-anterior sectors, respectively. Regarding ACB, M(90,90) were 7 mm in the anterior direction and <5 mm elsewhere. M(90,90)95%/99% did not significantly differ from M(90,90). The %volume excluded by the ACB margin was<2% for all male and <5% for 9/10 female patients. The dosimetry impact on R_adapt for the patients with the largest residual error was negligible.ConclusionsLocal deformation measurements confirm an anisotropic motion of rectum once set-up error is rigidly corrected. Margins of 7 mm anterior and 5 mm elsewhere are adequate for ACB. Female patients show a slightly larger residual error.  相似文献   

17.

Background

Prior microrheologic assessments of selected, microlitre plugs of cystic fibrosis (CF) sputum suggest no intrinsic rheologic abnormality. However, such analyses may not be representative of CF sputum as a whole. We therefore reassessed this question using whole sputum macrorheology. Additionally, we wished to further explore the relationships between sputum rheology, inflammation and infection.

Methods

Dynamic oscillatory macrorheometry was performed on whole expectorated sputum from stable adults with CF (n = 18) and COPD (n = 12) and induced sputum from normal controls (n = 7). Concomitant sputum inflammatory mediator levels were measured in CF and COPD samples. Sputum collected from CF subjects (n = 6) at commencement and completion of intravenous antibiotic therapy for an infective exacerbation was also assessed.

Results

CF sputum neutrophil elastase activity (NE) was significantly related to degree of sputum purulence (p = 0.049) and correlated significantly with measures of sputum viscoelasticity (r = 0.696, p = 0.008 for storage modulus G'' at 9 Hz). There were significant differences in viscoelasticity between subject groups when samples were compared irrespective of appearance/degree of sputum purulence. However, the macrorheology of mucoid CF sputum did not differ from normal sputum (eg median (range) G'' at 9 Hz 2.25 (0.79, 3.26) vs 2.04 (1.4,4.6) Pa, p = 1). In contrast, mucoid COPD samples demonstrated significantly greater viscoelasticity (G'' at 9 Hz 4.5 (2.4, 23) Pa) than sputum from both CF (p = 0.048) & normal subjects (p = 0.009). Antibiotic therapy during exacerbations was associated with significant reductions in CF sputum viscoelasticity, with mean (SD) G'' at 9 Hz decreasing from 28.5 (11.5) Pa at commencement to 6.4 (4.6) Pa on day 7 (p = 0.01).

Conclusion

The macrorheologic properties of whole, mucoid CF sputum are not different from normal, confirming the results of prior microrheologic studies. Instead, CF sputum viscoelasticity is related to secondary infection, decreases with intravenous antibiotic therapy and correlates with inflammation. In contrast, COPD sputum demonstrates inherently greater viscoelasticity, providing a novel target for potential therapeutic interventions.  相似文献   

18.

Introduction

Cystic fibrosis (CF) airways are colonized by a polymicrobial community of organisms, termed the CF microbiota. We sought to define the microbial constituents of the home environment of individuals with CF and determine if it may serve as a latent reservoir for infection.

Methods

Six patients with newly identified CF pathogens were included. An investigator collected repeat sputum and multiple environmental samples from their homes. Bacteria were cultured under both aerobic and anaerobic conditions. Morphologically distinct colonies were selected, purified and identified to the genus and species level through 16S rRNA gene sequencing. When concordant organisms were identified in sputum and environment, pulsed-field gel electrophoresis (PFGE) was performed to determine relatedness. Culture-independent bacterial profiling of each sample was carried out by Illumina sequencing of the V3 region of the 16s RNA gene.

Results

New respiratory pathogens prompting investigation included: Mycobacterium abscessus(2), Stenotrophomonas maltophilia(3), Pseudomonas aeruginosa(3), Pseudomonas fluorescens(1), Nocardia spp.(1), and Achromobacter xylosoxidans(1). A median 25 organisms/patient were cultured from sputum. A median 125 organisms/home were cultured from environmental sites. Several organisms commonly found in the CF lung microbiome were identified within the home environments of these patients. Concordant species included members of the following genera: Brevibacterium(1), Microbacterium(1), Staphylococcus(3), Stenotrophomonas(2), Streptococcus(2), Sphingomonas(1), and Pseudomonas(4). PFGE confirmed related strains (one episode each of Sphinogomonas and P. aeruginosa) from the environment and airways were identified in two patients. Culture-independent assessment confirmed that many organisms were not identified using culture-dependent techniques.

Conclusions

Members of the CF microbiota can be found as constituents of the home environment in individuals with CF. While the majority of isolates from the home environment were not genetically related to those isolated from the lower airways of individuals with CF suggesting alternate sources of infection were more common, a few genetically related isolates were indeed identified. As such, the home environment may rarely serve as either the source of infection or a persistent reservoir for re-infection after clearance.  相似文献   

19.
A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of three Pseudomonas species belonging to the mendocina sublineage (P. oleovorans, P. pseudoalcaligenes, and P. oleovorans subsp. lubricantis) found in contaminated metalworking fluids (MWFs). These microbes are the primary colonizers and serve as indicator organisms of biodegradation of used MWFs. Molecular techniques such as qPCR are preferred for the detection of these microbes since they grow poorly on typical growth media such as R2A agar and Pseudomonas isolation agar (PIA). Traditional culturing techniques not only underestimate the actual distribution of these bacteria but are also time-consuming. The primer–probe pair developed from gyrase B (gyrB) sequences of the targeted bacteria was highly sensitive and specific for the three species. qPCR was performed with both whole cell and genomic DNA to confirm the specificity and sensitivity of the assay. The sensitivity of the assay was 101 colony forming units (CFU)/ml for whole cell and 13.7 fg with genomic DNA. The primer–probe pair was successful in determining concentrations from used MWF samples, indicating levels between 2.9 × 103 and 3.9 × 106 CFU/ml. In contrast, the total count of Pseudomonas sp. recovered on PIA was in the range of <1.0 × 101 to 1.4 × 105 CFU/ml for the same samples. Based on these results from the qPCR assay, the designed TaqMan primer–probe pair can be efficiently used for rapid (within 2 h) determination of the distribution of these species of Pseudomonas in contaminated MWFs.  相似文献   

20.
赵坚  任涛 《中国微生态学杂志》2011,23(4):361-362,364
目的探讨慢性阻塞性肺病急性加重期(AECOPD)下呼吸道病原菌群的分布及分析药敏试验结果。方法对仙居县人民医院呼吸病房收治的128例AECOPD患者的痰细菌培养和药敏试验结果进行分析。结果 AECOPD患者感染的病原菌中,革兰阴性杆菌占61.95%,以铜绿假单胞菌、肺炎克雷伯菌、鲍曼不动杆菌为主;革兰阳性球菌占21.43%,以金黄色葡萄球菌、粪肠球菌为主;真菌占14.88%;2种以上病原菌混合感染占20.31%。体外药敏试验发现:亚胺培南对大部分革兰阴性杆菌有较好敏感性,万古霉素对大部分革兰阳性球菌有较好敏感性,检出的真菌对氟胞嘧啶、两性霉素、氟康唑、依曲康唑均保持较高敏感性。结论 AECOPD患者下呼吸道感染病原菌以革兰阴性杆菌为主,真菌感染率和混合感染率较高,应引起重视,应根据药敏结果合理选用抗菌药物。  相似文献   

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