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Microbiologically documented nosocomial infections after coronary artery bypass surgery without cardiopulmonary bypass.

OBJECTIVE: This study was undertaken to evaluate the frequency, characteristics, and risk factors of microbiologically documented nosocomial infections after off-pump coronary artery bypass grafting. METHODS: A prospective cohort study was performed at Henry Dunant Hospital, Athens, Greece. It included all adult patients who underwent coronary artery bypass grafting with no valve surgery and without the use of cardiopulmonary bypass during a period of 3 years. Case patients were those with development of microbiologically documented nosocomial infections. Various variables were examined as possible risk factors for nosocomial infections. RESULTS: Twenty-one of 782 studied patients (2.7%) acquired 26 microbiologically documented nosocomial infections after off-pump coronary artery bypass grafting. Eight of 782 studied patients had pneumonia (1.02%), 7 of 782 (0.90%) had bacteremia, 4 of 782 (0.51%) had superficial wound infection at the sternotomy site, 4 of 782 (0.51%) had urinary tract infection, 2 of 782 (0.26%) had mediastinitis, and 1 of 782 (0.13%) had pressure sore infection. Twenty-one infections were monomicrobial, whereas 5 were polymicrobial. All polymicrobial infections were wound infections. There was a statistically significant difference in mortality between patients with and without nosocomial infection (23.8% vs 1.2%, P < .001). Clinical response of the infection to the treatment administered was observed in 21 of 26 episodes (80.8%) in 21 patients. A backward stepwise multivariable logistic regression model showed that independent risk factors (P < .05) associated with development of microbiologically documented nosocomial infection were arterial hypertension, previous vascular surgery, urgent operation, postoperative atrial fibrillation, number of inotropes used during and after operation, transfusion of fresh-frozen plasma during the intensive care unit stay, and intensive care unit stay until development of infection. CONCLUSION: Nosocomial infection after off-pump coronary artery bypass grafting is an uncommon but potentially life-threatening complication. The identification of independent risk factors, including arterial hypertension, associated with development of postoperative infection may help in the development of clinical strategies for the prevention, early diagnosis, and treatment of these infections.

Adult↗

Clinical and microbiological profile of microsporidial keratoconjunctivitis in southern India.

PURPOSE: To report the clinical and microbiological profile of microsporidial keratoconjunctivitis in immunocompetent individuals in southern India. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Nineteen cases of microsporidial keratoconjunctivitis diagnosed between January 2002 and December 2004 were studied. METHODS: All medical and laboratory records of patients with infectious keratitis during the study period were reviewed. In all cases, after relevant history recording and slit-lamp examination, corneal/conjunctival scrapings were collected. Multiple scrapings were taken from the lesions and examined by fluorescence or light microscopy after staining with potassium hydroxide and calcofluor white (KOH + CFW), Gram's stain, Kinyoun's, and Giemsa stain. In some cases, the serum was tested for human immunodeficiency virus antibody by enzyme-linked immunosorbent assay. MAIN OUTCOME MEASURES: Clinical course, demographic features, predisposing factors, microbiological profile, treatment, and final outcome. RESULTS: Of 4822 cases of suspected microbial keratitis seen during the period, 19 (0.4%) were identified as microbiologically proven microsporidial keratitis. All patients were apparently healthy; 8 had a history of ocular trauma, and 3 mentioned bathing in unclean river water. All but 2 had unilateral involvement. The mean age of the patients was 38.4+/-13.7 years (range, 23-73). The duration of symptoms ranged from 1 day to 2 years, with 11 of 19 (58%) presenting within a week of onset of symptoms. Slit-lamp examination revealed multifocal, coarse, punctate, raised epithelial lesions in all patients. A mild to moderate nonpurulent conjunctivitis was present in all cases, with papillary and/or follicular reaction in 14. Corneal/conjunctival scrapings demonstrated microsporidial spores by KOH + CFW in 16 of 17 cases tested, whereas the diagnosis was made by Giemsa stain in 2 cases and by Gram's stain in one. Kinyoun's (1% acid fast) stain was confirmatory in all cases. In all patients, treatment was started after debridement and included oral and/or topical antimicrobial agents. At last follow-up, 15 of 19 achieved a visual acuity of 20/20. CONCLUSIONS: Microsporidial keratoconjunctivitis should be considered in the differential diagnosis of atypical punctate epithelial keratitis associated with conjunctivitis and can be diagnosed by routine microbiological methods. The disease can occur in healthy individuals, and the outcome of treatment is often satisfactory.

Adult↗

Use of high-performance liquid chromatographic and microbiological analyses for evaluating the presence or absence of active metabolites of the antifungal posaconazole in human plasma.

Posaconazole (SCH 56592) is a novel broad spectrum triazole antifungal agent that is currently in phase III clinical trials for the treatment of systemic fungal infections. This study was initiated to determine if orally administered posaconazole to humans would result in the formation of active metabolite(s). Plasma samples from a multiple-rising dose study in healthy volunteers were analyzed by validated HPLC and microbiological methods. The HPLC analysis involved extraction with a mixture of organic solvent (methylene chloride-hexane) followed by separation on a C18 column and quantification by UV absorbance at 262 nm. The microbiological assay was performed utilizing an agar diffusion method using Candida pseudorropicalis ATCC 46764 as the test organism. Potency was determined by comparing the growth inhibition zones produced by the test sample to those produced by standard concentrations prepared in plasma. Individual and mean plasma concentration-time profiles were similar for both HPLC and microbiological assays. The area under the plasma concentration-time curves of the microbiological and HPLC results were similar with a mean (RSD) ratio of 105.5% 15.3%), indicating that there was no relevant biologically active metabolite of posaconazole in human plasma.

Antifungal Agents↗

Evaluation of agent and host factors in progression of mycotic keratitis: A histologic and microbiologic study of 167 corneal buttons.

PURPOSE: To evaluate the host and agent factors in the progression of mycotic keratitis through the microbiologic evaluation and histologic study of human corneal buttons obtained at the time of therapeutic keratoplasty. DESIGN: Retrospective noncomparative consecutive case series. MATERIALS: One hundred sixty-seven corneal buttons from 148 patients of microbiologically diagnosed and treated cases of mycotic keratitis who underwent therapeutic keratoplasty between January 1995 and May 1998. METHODS: Therapeutic penetrating keratoplasty, review of microbiologic results, histopathologic and microbiologic evaluation of the corneal buttons of mycotic keratitis MAIN OUTCOME MEASURES: Histologic evaluation of the buttons for morphologic changes, degree and distribution of inflammatory cells, presence or absence of fungal filaments, and their degree and distribution within the corneal buttons. RESULTS: The diagnosis of fungal infection was made on corneal scrapings in 36 cases; whereas in 131 (78%), the fungus was grown in cultures and identified as Aspergillus in 55 (42%), Fusarium in 42 (32%), unidentified hyaline fungi in 22 (17%), dematiaceous (unidentified) in 4 (3%), and others in 8 (6%). The mean interval between diagnosis and keratoplasty was 19 (+/-40) days. From the keratoplasty specimen, the fungus was identified at histologic examination in 127 of 167 (76%) buttons and grown by culture techniques in 76 of 115 (66%) buttons. The fungal species identified in the corneal button were Fusarium in 30 (39%); Aspergillus in 25 (33%); unidentified hyaline in 19 (25%), and others in 2 (3%). Fungus-positive corneal buttons had early surgery (mean, 15 days) compared with fungus-negative (39 days) corneal buttons (P = 0.0005), with 93% fungus positivity in the buttons removed within 2 weeks and 42% after 2 months. In the fungus-positive buttons, there was an inverse correlation between the degree, distribution of inflammatory cells, and fungal filaments (r = -0.255, P = 0.024; r = -0.199, P = 0.027), respectively. The factors necessitating an early keratoplasty were heavy fungal load, deeper penetration of fungus, and possibly insufficient inflammation to combat infection. A granulomatous reaction was noted in the posterior stroma and around the fragmented Descemet's membrane in 23 buttons (13.8%), independent of fungal species. Inflammation was unaffected by elimination of fungus and increasing interval between diagnosis and treatment. CONCLUSIONS: Rapid progression of mycotic keratitis in the early phases is by agent factors such as heavy load and deeper penetration of the fungus, insufficient inflammatory response, and possibly relative ineffectiveness of antifungal agents. Progression in the later phase of mycotic keratitis need not necessarily be agent mediated; it could be either host-modulated, species-related, or drug resistance, thereby suggesting that ideal treatment regimens should include sensitivity-based antifungal therapy aided by in vivo monitoring of fungal filaments.

Adolescent↗

Phagocytosis and intracellular killing of Candida albicans blastoconidia by neutrophils and macrophages: a comparison of different microbiological test systems.

Polymorphonuclear neutrophils (PMN) and mononuclear phagocytes represent an important first line and effector function in the control of Candida infections. Their relative contribution to host defence is frequently assessed by means of microbiological assays. However, reported results are divergent and might well be associated with study design-related issues. In the present study, we compared frequently used microbiological candidacidal assays, with the purpose of determining the most adequate method for assessment of phagocytosis and intracellular killing. We concluded that microbiological assays using yeast-phagocyte suspensions are inappropriate for the assessment of intracellular killing of Candida blastoconidia by murine macrophages, due to adherence or clumping of cells. In contrast, an adherent monolayer of phagocytes can be applied as a single microbiological assay to independently study the process of phagocytosis and intracellular killing, by exudate peritoneal macrophages as well as exudate peritoneal PMN.

Animals↗

Neomycin: microbiological assay or liquid chromatography?

In a multicentre study involving six laboratories, a microbiological assay was performed on three neomycin samples containing respectively, 0.12, 2.1 and 11% (m/m) of neomycin C, as well on a pure neomycin C sample. The potency was determined according to the European Pharmacopoeia method but using a neomycin B base standard. The relative standard deviations between laboratories (RSD) on the potencies varied from 4.8 to 50%, depending on the sample examined. The RSD increased with the neomycin C content of the samples and the highest RSD values were observed for the pure neomycin C sample. The activity of neomycin C relative to neomycin B was found to be 62% by diffusion (RSD:41%) and 56% by turbidimetry (RSD: 50%). This confirmed that the presence of neomycin C in a neomycin sample influences the reproducibility of the microbiological assay. T estimate the influence of this effect on official standard, their composition was verified by liquid chromatography. The neomycin C base content of the standards varied between 0.4 and 5.8% (m/m). Based on the results obtained and on formerly published reports discussing problems encountered with microbiological assay of neomycin, it is proposed to introduce liquid chromatography in official monographs to replace microbiological assay.

Anti-Bacterial Agents↗

Microbiologic data overview of Italian cystic fibrosis patients.

The aim of our study was to determine the frequency of microbiological culturing and prevalence of colonization by principal pathogens of the respiratory tract of Italian cystic fibrosis patients. Data on all Italian cystic fibrosis patients were collected using a questionnaire sent to all Italian CF Centers. Results were obtained of microbiological cultures from 2,521 patients. Information was gained regarding the method of gathering biological samples, the percentage of patients undergoing microbiological culturing regularly, the procedures used to isolate bacteria and types of culture media used which were selective for Burkholderia cepacia. Ninety-four percent of Italian CF patients are regularly tested microbiologically. Sputum and pharyngeal cultures are most often carried out. 49% of Italian patients are colonized by Staphylococcus aureus, 5.4% by Haemophilus influenzae, 48.9% by Pseudomonas aeruginosa and 3.8% by Burkholderia cepacia. In Italy there is a high prevalence of CF patients colonized by Staphylococcus aureus and a low prevalence of patients colonized by Haemophilus influenzae. The prevalence of Burkholderia cepacia and Pseudomonas aeruginosa does not differe significantly from other countries examined.

Adolescent↗

Diagnostic characteristics of clinical and microbiological tests for monitoring periodontal and peri-implant mucosal tissue conditions during supportive periodontal therapy (SPT).

The aim of this study was to evaluate a clinical and a microbiological test for monitoring tissue condition during supportive periodontal therapy (SPT) and to compare their diagnostic characteristics at implant and tooth sites. Twelve female (age: 37-72 years) and 7 male patients (age: 26-83 years) were evaluated in this study on the basis of availability to follow a rigid SPT program. Patients had received a complete periodontal examination at 1 and 5 years after implant placement. This included standardized radiographs obtained at implants and matching control teeth. One implant site and one tooth site per patient were followed during the last 2 years of the SPT program. At each recall visit microbiological samples were analyzed according to DNA/RNA analysis identifying periodontal pathogens (IAI Pado Test 4.5, Institute for Applied Immunology, Zuchwil, Switzerland). Presence or absence of bleeding on probing at these sites was also noted using a standardized probing force of 0.25 N (Audio Probe, ESRO, Thalwil ZH, Switzerland). The percentage number of recall visits with positive bacteriological test results and positive BOP scores were calculated. Disease progression at the sites was defined if the annual increase in probing depth was > or = 0.5 mm/year (2.5 mm in 5 years) or if the annual decrease in CADIA values (Computer Assisted Densitometric Image Analysis) was more than -0.7 per year (-3.5 in 5 years). Changes below these values were considered as negative test results indicating stability of the sites. The diagnostic characteristics (sensitivity, specificity, positive and negative predictive values) of BOP and microbiological tests alone or in combination were then calculated using two-by-two tables. By application of increasing thresholds of BOP frequencies set for definition of positive test outcome (BOP > or = 10% > or = 20% > or = 25% > or = 50% > or = 75% > or = 90% or the combined BOP > or = 75%, but DNA positive > or = 10%, > or = 25% > or = 34% > or = 50% > or = 67% > or = 90%) receiver operator characteristics curves (ROC) were constructed for teeth and implants. The areas under the ROC curves were calculated and compared by means of chi-square tests. The results indicated statistically significant better diagnostic characteristics of both tests at implants compared to teeth. The inclusion of an additional microbiological test significantly enhanced the diagnostic characteristics of BOP alone at teeth as well as at implants.

Adult↗

The periodontal abscess (I). Clinical and microbiological findings.

BACKGROUND/AIMS: Little information is available regarding the diagnosis and microbiology of periodontal abscesses. The aim of this descriptive clinical and microbiological study was to provide more information in order to help in the characterisation of the periodontal abscess associated to periodontitis. METHOD: 29 consecutive patients with a periodontal abscess were studied by the assessment of clinical variables, including both subjective (pain, edema, redness and swelling) and objective (bleeding on probing, suppuration, probing pocket depth, tooth mobility and cervical lymphadenopathy) parameters. Microbiological samples were taken for anaerobic microbiology and processed by means of culture. Systemic involvement was also studied through the analysis of blood and urine samples using conventional laboratory standards. RESULTS: 62% of the abscesses affected untreated periodontitis patients, and 69% were associated with a molar tooth. More than 75% of the abscesses had moderate-severe scores related to edema, redness and swelling, and 90% of the patients reported pain. Bleeding occurred in all abscesses, while suppuration on sampling was detected in 66%. Mean associated pocket depth was 7.28 mm, and 79% of teeth presented some degree of mobility. Cervical lymphadenopathy was seen in 10% of patients, while elevated leucocyte counts were observed in 31.6%. The absolute number of neutrophils was elevated in 42% of the patients. High prevalences of putative periodontal pathogens were found, including Fusobacterium nucleatum, Peptostreptococcus micros, Porphyromonas gingivalis, Prevotella intermedia and Bacteroides forsythus. CONCLUSIONS: The periodontal abscess has clear clinical characteristics and is usually associated with severe periodontal destruction. This condition may cause systemic involvement and the lesion generally has a large bacterial mass with a high prevalence of well-recognised periodontal pathogens.

Acute Disease↗

The rôle of chlorhexidine in the one-stage full-mouth disinfection treatment of patients with advanced adult periodontitis. Long-term clinical and microbiological observations.

BACKGROUND/AIMS: Recent studies reported significant additional clinical and microbiological improvements when severe adult periodontitis was treated by means of a "one-stage full-mouth" disinfection instead of a standard treatment strategy with consecutive root planings quadrant per quadrant. The one stage full-mouth disinfection procedure involves scaling and root planing of all pockets within 24 h in combination with an extensive application of chlorhexidine to all intra-oral niches such as periodontal pockets, tongue dorsum, tonsils (chairside, and at home for 2 months). This study aims to examine the relative importance of the use of chlorhexidine in the one stage full-mouth disinfection protocol. METHODS: Therefore, 3 groups of 12 patients each with advanced periodontitis were followed, both from a clinical and microbiological point of view, over a period of 8 months. The patients from the control group were scaled and root planed, quadrant per quadrant. at two-week intervals. The 2 other groups underwent a one stage full-mouth scaling and root planing (all pockets within 24 h) with (Fdis) or without (FRp=full-mouth root planing) the adjunctive use of chlorhexidine. At baseline and after 1, 2, 4 and 8 months, the following clinical parameters were recorded: plaque and gingivitis indices, probing depth, bleeding on probing and clinical attachment level. Microbiological samples were taken from different intra-oral niches (tongue, mucosa, saliva and pooled samples from single- and multi-rooted teeth). The samples were cultured on selective and non-selective media in order to evaluate the number of CFU/ml for the key-periodontopathogens. At baseline, an anonymous questionnaire was given to the patients to record the perception of each treatment (post operative pain, fever, swelling etc.). RESULTS: All 3 treatment strategies resulted in significant improvements for all clinical parameters, but the Fdis and FRp patients reacted always significantly more favourably than the control group, with an additional probing depth reduction of +/- 1.5 mm and an additional gain in attachment of +/- 2 mm (for pockets > or = 7 mm). Also from a microbiological point of view both the FRp and Fdis patients showed additional improvements when compared to the control group, as well in the reduction of spirochetes and motile organisms as in the number of CFU/ml of the key-pathogens, especially when the subgingival plaque samples were considered. The differences between FRp and Fdis patients were negligible. CONCLUSIONS: These findings suggest that the benefits of a "one-stage full-mouth disinfection" in the treatment of patients suffering from severe adult periodontitis probably results from the full-mouth scaling and root planing within 24 h rather than the beneficial effect of chlorhexidine. The raise in body temperature the second day after the full-mouth scaling and root planing seems to indicate a Shwartzman reaction.

Adult↗

Untreated periodontal disease in Indonesian adolescents. Longitudinal clinical data and prospective clinical and microbiological risk assessment.

BACKGROUND, AIMS: In order to investigate the r le of various putative clinical and microbiological risk markers, a longitudinal study was initiated in a young population deprived of regular dental care. In 1987 all inhabitants in the age range 15-25 years living in a village with approximately 2,000 inhabitants at a tea estate on Western Java, Indonesia, were examined clinically and microbiologically. In total, 167 subjects of the original group of 255 adolescents were re-examined in 1994. The material presented in this paper describes the clinical periodontal condition at baseline (1987) and at follow-up (1994), 7 years later. Furthermore, the relationship between progression of the disease and baseline clinical and microbiological data was assessed. METHODS: Plaque index (PI), bleeding on probing (BOP), pocket depth (PD), and attachment loss (AL) were scored at the approximal surfaces of the vestibular aspects of all teeth. The number of approximal surfaces of the Ramfjord teeth showing subgingival calculus was recorded. At baseline, the dorsum of the tongue, the buccal gingiva in the upper jaw, the saliva and the deepest bleeding pocket without clinical loss of attachment were sampled for microbiological examination with phase contrast microscopy and indirect immunofluorescence. RESULTS: Mean values at baseline and at follow-up were PI: 1.01 and 1.15, BOP: 0.80 and 1.16, PD 3.26 mm and 3.32 mm, AL: 0.33 mm and 0.73 mm, respectively. All parameters except PD showed a statistically significant increase over the 7-year period. The prevalence of the studied bacteria irrespective of the sample site was: A. actinomycetemcomitans 53%, P. gingivalis 88%, P. intermedia 100%, spirochetes 89% and motile micro-organisms 100%. At the full mouth level, logistic regression showed significant odds ratios for progressive disease with age (1.15), subgingival calculus (1.20) and subgingival presence of A. actinomycetemcomitans (4.61). Presence of any of the selected micro-organisms on the mucous membranes was not related with progressive disease. In order to study local factors to explain local disease activity, each subject was characterized using the sampled pocket, which was the deepest bleeding pocket without LA at baseline, as a single response site per patient. In this constrained design, the main statistical factors associated with progressive disease were presence of motile micro-organisms and the plaque score. CONCLUSIONS: This study identified 3 main risk markers for disease progression at the full mouth level: age, amount of subgingival calculus and subgingival presence of A. actinomycetemcomitans.

Adolescent↗

Nasal endoscopy in asthmatic children: assessment of rhinosinusitis and adenoiditis incidence, correlations with cytology and microbiology.

BACKGROUND: Upper respiratory airway diseases may induce a worsening of asthma. Sinusitis represents one of the most common chronic diseases. The association of asthma and sinusitis varies greatly in different studies, depending on diagnostic procedures. OBJECTIVE: The aims were: (i) to demonstrate that nasal endoscopy may be easily feasible in asthma at paediatric age; (ii) to evaluate the incidence of rhinosinusitis and adenoiditis in children with asthma by nasal endoscopy; (iii) to correlate inflammatory parameters such as cytology and microbiological cultures with nasal endoscopy findings. SUBJECTS AND METHODS: One hundred and forty-five asthmatic children were evaluated, 48 males and 97 females, with an average age of 7.27 years. Evaluated parameters were the incidence of rhinosinusal infections in asthmatic children, and the role of: (i) nasal endoscopy, (ii) nasal cytology, and (iii) nasal microbiology in their diagnoses. RESULTS: Nasal endoscopy was successfully performed on 128 patients. Twenty-six children had endoscopic rhinosinusitis alone, 10 had adenoiditis alone, and 35 showed endoscopic rhinosinusitis associated with adenoiditis. There were significant correlations between endoscopic rhinosinusitis and adenoiditis (P < 0.001), between clinical and endoscopic rhinosinusitis (P < 0.001), between endoscopic rhinosinusitis and adenoiditis and microbiology (P < 0.05 and P < 0.0001, respectively), and between microbiology and cytology (P < 0.05). CONCLUSION: This study shows that rhinosinusal infections are common in asthmatic children. Moreover, nasal endoscopy might represent a fruitful tool in the management of asthmatic children.

Adenoids↗

Bioptic microbiology in the differential diagnosis of enterocolitis.

Parameters in the differential diagnosis of enterocolitis have been poorly evident for many years. Development and profitable employment of endoscopic instruments were the first step towards advancing the diagnostic facilities in inflammatory bowel disease. The microbiologic examination of mucosal biopsies creates a new diagnostic dimension, and it distinctly seems to increase the diagnostic sensitivity for pathogens. Within fifteen months 152 patients admitted to the gastroenterologic unit with acute, or symptoms of exacerbated, bowel disease were examined for the aetiologic agents. Compared with former reports, idiopathic inflammatory bowel disease (IIBD) such as Crohn's disease (32.2%) and ulcerative colitis (18.4%) were decreased. Infectious colitis (22.3%), mostly Campylobacter or Yersinia infections, was, sometimes exclusively, diagnosed by bioptic microbiology, non-classifiable forms of colitis (21.7%), and rare forms (5.4%) were diagnosed more often. It proved to be important that IIBD was frequently superinfected by Campylobacter, Yersinia and Chlamydia, and the differential diagnosis was complicated, since these microorganisms can mimic IIBD. The results suggest that coloileoscopy combined with bioptic microbiologic investigation additional to faecal samples should include a search for Campylobacter and Yersinia. It appears indispensable that the final diagnosis "Crohn's disease" or "ulcerative colitis" should be confirmed by sequential coloileoscopy and microbiologic examination.

Adolescent↗

Feasibility of an in vitro microbiological model as an alternative to the rabbit eye model.

Ocular inserts of gentamicin sulfate with polyvinyl alcohol (PVA) 1.5%, 2.0%, and 2.5% and a combination of methyl cellulose 2% and Eudragit NE 30D 30%, 35%, and 40% w/w of methyl cellulose were fabricated by a casting technique. The inserts were sterilized by gamma radiation at 25 kGy and tested for sterility. The microbiological efficacy of the ocular inserts against Staphylococcus aureus ATCC 6538P and Pseudomonas aeruginosa NCIM 2200 was evaluated by developing an in vitro microbiological model and an in vivo noninvasive rabbit eye model. Parameters of the in vitro microbiological model were varied, and the results correlated with a noninvasive rabbit eye model. The in vitro model proved to be a viable alternative to the rabbit eye model in evaluating the microbiological efficacy of gentamicin sulfate ocular inserts.

Administration, Topical↗

How many nosocomial infections are missed if identification is restricted to patients with either microbiology reports or antibiotic administration?

OBJECTIVE: To investigate how many nosocomial infections would be missed if surveillance activities were restricted to patients having either microbiology reports or antibiotic administration. DESIGN: Analysis of data from a large prevalence study on nosocomial infections (Nosocomial Infections in Germany-Surveillance and Prevention). SETTING: A total of 14,966 patients were investigated in medical, surgical, obstetric-gynecologic, and intensive-care units of 72 German hospitals representatively selected according to size. Five hundred eighteen patients (3.5%) had at least one nosocomial infection. Microbiology reports were available for 56.6% of these patients on the prevalence day, and 86.3% received antibiotics. RESULTS: Only 31 nosocomially infected patients (6%) would have been missed by using either microbiology reports or antibiotic treatment as an indicator. These indicators of nosocomial infections had a high diagnostic sensitivity for nosocomial pneumonia (98.8%), urinary tract infections (96.3%), and primary bloodstream infections (95.3%), but a lower sensitivity for wound infections (85.4%). Thus, 97.4% of all nosocomial infections were found with this method in intensive-care units and 96.1% in medicine units, but only 89.7% in surgical departments. In 9 (12.5%) of 72 hospitals, the overall sensitivity would have been <80% using a combination of the two indicators. For this reason, the situation in one's own hospital should be checked before using this method. CONCLUSIONS: After checking the situation in one's own hospital, the "either-or" approach using the two indicators "microbiology report" and "antibiotic administration" can be recommended as a time-saving measure to diagnose pneumonia, urinary tract, and primary bloodstream infections. For wound infections, additional information obtained by changing dressings or participating in ward rounds is necessary to achieve satisfactory sensitivity in the surveillance of nosocomial infections. Of course, it is necessary that the surveillance staff discard all false positives to ensure a satisfactory specificity.

Anti-Bacterial Agents↗

The folacin contents of foods as measured by a radiometric microbiologic method.

A radiometric microbiologic assay for folate was applied to measure food folacin levels. Sixteen different foods were analyzed. The total folacin content of the 16 foods obtained by the radiometric microbiologic method was found to compare well with that obtained by the turbidimetric microbiologic method. The folacin content ranged from 9 ng/ml of frozen reconstituted grape juice to 1820 micrograms/100 g of the cereal Total. The study showed that the radiometric microbiologic assay can be used to measure folacin content in foods.

Biological Assay↗

Histopathologic and microbiologic aspects of ventilator-associated pneumonia.

BACKGROUND: The relationship between microbiology and histology in patients with ventilator-associated pneumonia has been sparsely described. METHODS: Twenty-five patients who died in the intensive care unit after their lungs had been mechanically ventilated for 72 h were studied. Twenty of the 25 died with clinical suspicion of pulmonary infection. A total of 375 immediate postmortem pulmonary biopsies were obtained after death and processed for quantitative microbiology and histology. Four evolutionary stages of pneumonia were defined: early, intermediate, advanced, and resolution. RESULTS: At least one specimen with histologic evidence of pneumonia was found in all but two patients (92%). Histologic pneumonia was a widespread and frequent process (46%) of biopsies examined) involving predominantly the lower lobes (55% of all biopsies with pneumonia) and showing different histopathologic stages of progression coexisting in the same lung lobes. Lung cultures were frequently polymicrobial (149 of 375, 40% of the pulmonary biopsy cultures, and 20 of 25, 80% of the cases) and not always yielding the same pathogen (19 microorganisms) when comparing one lung to the other. Histopathology and microbiologic biopsy cultures showed a weak relationship (28% and 49% of species had counts > or = 10(3) cfu/g in samples without pneumonia from patients with and without prior antibiotic treatment, respectively). Histopathologic evolutionary stages were not associated with any differences in quantitative culture results of pulmonary biopsies, independently of prior administration of antibiotics. Higher bacterial concentrations of biopsy cultures were associated with the absence of prior antibiotic treatment. CONCLUSIONS: Ventilator-associated pneumonia is a frequent diffuse and polymicrobial process showing different coexisting degrees of evolution and involving preferentially the lower lobes. Microbiology and histology can be dissociated even in the absence of prior antibiotic treatment. Lung histology appears more reliable than bacteriology as a diagnostic reference test.

Adult↗

Exploiting molecular methods to explore endodontic infections: Part 1--current molecular technologies for microbiological diagnosis.

Endodontic infections have been traditionally studied by culture-dependent methods. However, as with other areas of clinical microbiology, culture-based investigations are plagued by significant problems, including the probable involvement of viable but uncultivable micro-organisms with disease causation and inaccurate microbial identification. Innumerous molecular technologies have been used for microbiological diagnosis in clinical microbiology, but only recently some of these techniques have been applied in endodontic microbiology research. This paper intended to review the main molecular methods that have been used or have the potential to be used in the study of endodontic infections. Moreover, advantages and limitations of current molecular techniques when compared to conventional methods for microbial identification are also discussed.

Bacterial Typing Techniques↗