Respiratory Secretions Of Patients Research Articles

Neutrophil bactericidal activity and host defenses in cystic fibrosis: a narrative review.

Cystic fibrosis (CF) is a disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR). Without properly functioning CFTR channels, chloride does not exit respiratory epithelial cells, and consequently the mucus lining the surface of the cells becomes thick. This viscous mucus accumulates and causes abnormal function of the mucociliary apparatus, which can lead to bacterial colonization, infections with Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), and eventually lung damage. Recent studies have shown that the increased susceptibility to respiratory infections in CF patients may also be due to defects in neutrophil function, but the exact mechanism is uncertain. The PubMed database was searched on February 10, 2023 and again on July 23, 2023 to compile a comprehensive list of clinical and experimental studies to evaluate neutrophil function in CF. The first search included a combination of MeSH terms: "cystic fibrosis" and "neutrophils/physiology". A separate second search included a combination of the MeSH terms: "neutrophils" and "cystic fibrosis transmembrane conductance regulator". Neutrophils from patients with CF have decreased transfer of chloride into phagolysosomes after bacterial ingestion and have dysregulated degranulation. This reduces the production of toxic oxidative radicals, especially hypochlorous acid (HOCl), and reduces bactericidal activity. CFTR potentiators correct the dysregulated degranulation in patients with CF and increased neutrophil killing activity. A reduced concentration of chloride in in vitro assays also reduces neutrophil killing activity; these observations are relevant to the reduced chloride concentrations in respiratory secretions in patients with CF. This literature review summarizes studies that demonstrate that an important defect in CF neutrophils lies in the oxygen-dependent pathway in phagolysosomes and studies with ivacaftor demonstrate that this drug corrects CF neutrophil function. These studies demonstrate the potential utility of using easily available neutrophils to study drug effects in CF patients.

Molecular detection of Mycoplasma pneumoniae in respiratory samples from hospitalized children

It is currently reported that Mycoplasma pneumoniae (MP) infection can occur at a young age. Objective: Describe the findings of the molecular detection of MP in respiratory secretions of patients who required hospitalization due to acute respiratory infection, in a pediatric hospital. Data collection was performed by reviewing medical records and statistical correlation using the chi-square test. 919 patients from one month to fourteen years and eleven months of age who required hospitalization for acute respiratory infection were included. The frequency by age and sex of the isolation of MP was analyzed together with other respiratory pathogens. Mycoplasma pneumoniae was the most frequently detected microorganism (30%), followed by respiratory syncytial virus (RSV) (25.1%). Age and sex did not behave as a predictor of detection for MP. In 47.3% of the patients, MP was isolated together with another pathogen, the most prevalent was RSV 31.3%. Regarding the diagnoses at discharge of the group of patients with isolation of MP and a another microorganism, 50.8% had bronchiolitis, and in the group of patients with identification only of MP this percentage was 32.4%. The difference in the distributions was statistically significant (p <0.05). We conclude that Mycoplasma pneumoniae detection is frequent in our environment and occurs in a significant number of cases together with another respiratory pathogen. These findings should prompt further study to determine their clinical relevance.

Characterization of Pseudomonas aeruginosa and Acinetobacter spp. in respiratory secretions of hospitalized patients in intensive care

Pseudomonas aeruginosa and Acinetobacter spp. are the microorganisms most frequently associated with serious healthcare-associated infections and death. The objective of the research consisted of characterizing the isolates of P. aeruginosa and A. spp. in respiratory secretions of patients hospitalized in the Clinical Surgical Hospital of Santa Clara, Villa Clara, Cuba between January 2014 and December 2018. A descriptive, longitudinal and retrospective study was carried out with the isolates of P. aeruginosa and A. spp. from the Clinical Surgical Hospital "Arnaldo Milián Castro" in the city of Santa Clara, Villa Clara province, Cuba between the months of January 2014 to December 2018. For the realization of this work, a discretionary and intentional sampling by criterion was selected. The population consisted of 2 207 isolates, and the sample consisted of 249 P. aeruginosa and 705 A. spp. The data were obtained from the record books of the respiratory samples section of the Microbiology Laboratory and were arranged in a documentary observation guide. A. spp., was the most frequently isolated microorganism in the intensive care units, with a uniform behavior during the entire series studied, while P. aeruginosa predominated in the first and fourth trimesters. A. spp., showed almost absolute levels of resistance throughout the study, while P. aeruginosa showed low percentages of resistance with a propensity to increase resistance. It is concluded that both microorganisms were the most frequently isolated in respiratory secretions in ICUs, surpassing in recent years’ other microorganisms, such as Gram-positive cocci and enterobacteria in general isolates and in HAIs, with marked prevalence rates for both genera, as well as an evident resistance, characterized by differences in relation to percentages, but with a propensity to increase it.

Control of serogroup W meningococcal disease outbreaks: the promise of adolescent vaccination

Meningococcal disease is a serious bacterial infection caused by Neisseria meningitidis, usually presenting as meningitis, bacteraemia, or both. Even with appropriate treatment, the case fatality rate is approximately 10–15%, and 10–20% of survivors have long-term sequelae.1 N meningitidis colonises the oropharynx and is spread through the respiratory secretions of patients with meningococcal disease or asymptomatic carriers. In many regions, including Europe, adolescents and young adults have the highest carriage rates and are thus considered to be the primary source of transmission to other age groups.

Australian dentists' knowledge, preparedness, and experiences during the COVID-19 pandemic.

BackgroundCOVID-19 is a global health crisis. Close contact with the mucous membranes and respiratory secretions of patients and aerosol-generating procedures renders dentists and other oral health professionals at high risk of exposure to SARS-CoV-2. We examined dentists’ knowledge, preparedness, and experiences of managing COVID-19 in Australia.MethodsA cross-sectional online survey of dentists with a current membership with The Australian Dental Association (ADA) was conducted between March and April 2021.ResultsOf the 368 survey responses, most dentists (72.3%) reported having a good level of knowledge about COVID-19, with most visiting the ADA Federal COVID-19 (74.7%) and state/territory department of health websites (62.8%), respectively to source up-to-date information. Most dentists (87.6%) felt prepared to manage COVID-19 into the future, although 66% reported not receiving training or certification in the use of PPE. Over half (58.7%) reported not being concerned about contracting SARS-CoV-2 at work, with some (28.9%, n = 98/339) feeling more stressed than usual and having heavier workloads.ConclusionCOVID-19 had significant impact in oral healthcare in Australia. Dentistry has adapted to the varied challenges raised by the pandemic. Comprehensive training and detailed guidelines were fundamental for successful patient management during the COVID-19 outbreak.

Management of bacteriological specimens of patients suffering from coronavirus disease 2019 (COVID-19)

Management of bacteriological specimens of patients suffering from coronavirus disease 2019 (COVID-19)

Molecular detection of bacterial pathogens in intensification of chronic obstructive pulmonary disease by polymerase chain reaction methods

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the major causes of mortality all around the world, and research indicates that it will become more prevalent in future. Patients with COPD may sometimes also catch bacterial infections, including infections with Streptococcus Pneumonia, Mycoplasma Pneumonia, and Legionella Pneumophila. The purpose of this study is to use PCR as more sensitive, supplementary method for detection of these infections. METHODS: The study is of the cross-sectional-descriptive type. 109 specimens were collected under supervision of pulmonologists from the respiratory secretions of patients with COPD and suspicion of bacterial infections. The specimens entered the DNA extraction process. Then, molecular experiments were performed, and their results were finally analyzed with statistical tests. RESULTS: There was no significant difference in terms of gender (P value>0.05). The patients’ average age was 62.4±12.2. In the case of Legionella Pneumophila, 4 of the 109 patients were identified as positive using the kit, and 2 of them were reported as positive with the second PCR method using the designed primers. As for Streptococcus Pneumonia, 8 of the 109 patients were identified as positive with the standard kit me thod, and 5 of them were reported as positive with the second PCR method. Relative frequency was calculated for Legionella Pneumophila and Streptococcus Pneumonia as 4% and 7%, respectively. CONCLUSIONS: In general, the methods employed in this study have good sensitivity and accuracy as compared to the conventional and common methods and to those in similar studies. Of course, it is suggested that the experiments be performed on more samples and with other genes.

Do Streptococcus pneumoniae and respiratory Syncytial virus synergise to promote invasive disease?

Streptococcus pneumoniae (S.p.) and Respiratory Syncytial Virus (RSV) are two major pathogens commonly found to coexist in respiratory secretions in patients with acute respiratory infection. Though there is increasing evidence of a synergistic interplay between these two pathobionts, the exact mechanisms remain obscure. The aim of our study was to decipher how coinfection with RSV alter pneumococcal growth dynamics and host immune response and how this impact on the colonisation and invasive properties of S.p. Using in vivo mouse model, we made the key observation that upon coinfection with RSV, the density of pneumococcal colonisation in the nasopharynx and dissemination to the lower respiratory tract were significantly higher in mice previously colonised with S.p. These mice also presented more severe weight loss and delayed recovery compared to mono-infected animals as well as significantly heightened pro-inflammatory cytokine profiles. Measurement of in vitro transepithelial electrical resistance (TEER) showed that, upon RSV coinfection, S.p. transmigrate through the epithelial barrier without altering epithelial integrity suggesting a transcellular mechanism rather than paracellular migration. Moreover, RSV-pneumococcal coinfection of human primary nasal epithelial cell demonstrated major changes in host protein expression involved in the catalytic activity, ubiquitination, cytoskeletal organisation, and endocytosis. Simultaneously, significant upregulation observed in bacterial proteins involved in the ribosomal activity, streptococcus-induced tissue inflammation, DNA supercoiling, and bacterial viability during oxidative stress, affecting both the survival and the virulence of S.p. Our results explain the complex interactions between pneumococci, RSV and host and help towards further understanding the significance of viral-bacterial co-infection in clinical settings.

Value of Broncho-Alveolar Lavage in Diagnosis of Newly Developed Lung Infiltrates in Mechanically Ventilated Patients

Background and Objectives: in a developing country, cost effectiveness is an important consideration. The aim of this study was to investigate the efficiency and safety of mini broncho-alveolar lavage (mini BAL) samples in the diagnosis of newly developed lung infiltrates in mechanically ventilated patients. Methods: fifty mechanically ventilated patients with newly developed lung infiltrates were assessed by mini-BAL and subsequent microbiological examination. An infant Ryle catheter FG-10 was used as the inner catheter, a Nelaton catheter size 18 FG was used as the outer protective catheter and was blocked by sterile K-Y gel instead of the pre-packaged catheters. Results: eighty six percent of samples collected by Mini-BAL technique from mechanically ventilated patients showed positive growth for culture and sensitivity. Thirty percent of patients had bi microbial infection while fourteen had polymicrobial infection. Fungal infection (Candida) was the most frequent isolated pathogen (32%) followed by Gram-negative bacteria (Klebsiella) (30%). Legionella was the commonest isolated atypical bacteria. Conclusion: this study highlighted the mini-BAL technique as a simple, safe, cheap, available and non-invasive bedside procedure for acquiring uncontaminated lower respiratory secretions in patients with newly developed pulmonary infiltrates.

Effects of an Airway Clearance Device on Inflammation, Bacteriology, and Mucus Transport in Bronchiectasis.

Bronchiectasis is characterized by abnormal and permanent dilation of the bronchi, caused by the perpetuation of inflammation and impairment of mucociliary clearance. Physiotherapy techniques can help to decrease the retention of respiratory secretions. The flutter valve combines high-frequency oscillation and positive expiratory pressure to facilitate the removal of secretions. We evaluated the effects of the flutter valve on sputum inflammation, microbiology, and transport of respiratory secretions in patients with bronchiectasis. Seventeen participants underwent sessions with flutter or control (flutter-sham), for 30 min/d, in a randomized crossover study, with 4 weeks with one of the therapies, a 2-week wash-out period, and then another 4 weeks with the other modality. Secretion samples were collected every week throughout the protocol and were assessed for the mucociliary transport, displacement in a simulated cough machine, contact angle, and cell cytology with percentage of neutrophil count, eosinophils, and macrophages, and the microbiology was assessed by the number of colony-forming units. Treatment with flutter resulted in greater displacement in a simulated cough machine and smaller contact angle, comparing the results between the first week (9.94 ± 3.12 cm and 26.5 ± 3.21°, respectively) and fourth week of treatment (13.96 ± 5.76 cm and 22.76 ± 3.64°, respectively) and was associated with a decrease in the total number of inflammatory cells. The use of a flutter valve for 30 min/d for at least 4 weeks is enough to change physical properties and improve mucus transport by coughing and can contribute to the reduction of the total number of inflammatory cells of the respiratory secretions of subjects with bronchiectasis. (ClinicalTrials.gov registration NCT01209546.).

Benefits of interventions for respiratory secretion management in adult palliative care patients-a systematic review.

BackgroundRespiratory secretions impact negatively on palliative patients. Unfortunately, a gold standard therapy is not yet available. The purpose of this study was to identify which interventions are in use to control respiratory secretions in patients with chronic disease with a poor prognosis and verify their effects on outcomes relevant for palliative care patients.MethodsA systematic review of the literature with narrative summary was conducted. We searched eight electronic databases in April 6th, 2016. Citation-tracking and reference list searches were conducted. We included randomized controlled trials, crossover trials, observational and qualitative studies regarding interventions for respiratory secretion management in adult patients with chronic diseases that met inclusion criteria indicating short prognosis.ResultsSix randomized controlled trials, 11 observational studies, ten crossover trials and one qualitative study were found. Interventions included mechanical insufflation-exsufflation (MIE), expiratory muscle training, manually-assisted cough, tracheotomy, chest physiotherapy, suctioning, air stacking, electrical stimulation of abdominal muscles, nebulized saline, positive expiratory pressure masks, percussive ventilation, high frequency chest wall oscillations. The interventions with most promising benefits to patients in palliative care were manually-assisted cough and mechanical insufflation-exsufflation to promote expectoration and percussive ventilation to improve mucous clearance.ConclusionTherapies, such as manually assisted cough, mechanical insufflation-exsufflation and percussive ventilation, which aim to deal with respiratory secretion, were the most promising treatment for use in palliative care for specific diseases. Nevertheless, the evidence still needs to improve in order to identify which treatment is the best.Electronic supplementary materialThe online version of this article (doi:10.1186/s12904-016-0147-y) contains supplementary material, which is available to authorized users.

Discrepancy in MALDI-TOF MS identification of uncommon Gram-negative bacteria from lower respiratory secretions in patients with cystic fibrosis.

IntroductionEarly identification of microbial organisms from respiratory secretions of patients with cystic fibrosis (CF) is important to guide therapeutic decisions. The objective was to compare the accuracy of matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) relative to the conventional phenotypic method in identifying common bacterial isolates, including nonfermenting Gram-negative bacteria, in a cohort of patients with CF.MethodsA total of 123 isolates from 50 patients with CF representing 14 bacterial species from respiratory specimens were identified using MALDI-TOF MS in parallel with conventional phenotypic methods. Discrepancies were confirmed by 16S ribosomal RNA (rRNA) gene sequencing in five Gram-negative isolates.ResultsThe MALDI-TOF MS managed to identify 122/123 (99.2%) bacterial isolates to the genus level and 118/123 (95.9%) were identified to the species level. The MALDI-TOF MS results were 100% consistent to the species level with conventional phenotypic identification for isolates of Staphylococcus aureus, Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pyogenes, Achromobacter xylosoxidans, Stenotrophomonas maltophilia, and other uncommon organisms such as Chryseobacterium gleum and Enterobacter cloacae. The 5/123 (4.6%) isolates misidentified were all Gram-negative bacteria. The isolation of E. cloacae and Haemophilus paraphrohaemolyticus may extend the potentially pathogenic list of organisms isolated from patients with CF.ConclusionAlthough the technique provides an early identification and antimicrobial therapy approach in patients with CF, limitation in the diagnosis of uncommon Gram-negative bacteria may exist.

Human Rhinovirus Infection in Children with Cystic Fibrosis

Nasopharyngeal swabs obtained from 78 pediatric patients with cystic fibrosis (CF), including 47 with acute pulmonary exacerbation and 31 in a stable clinical condition, were evaluated for 17 respiratory viruses. Human rhinovirus (HRV) was the most frequently detected virus in patients with pulmonary exacerbation and in those who were clinically stable (21.3% vs. 12.9%; P = 0.52). HRV-A was the main RV detected in patients with pulmonary exacerbations. However, no prevalence of particular HRV-A subtypes was found. This study highlights that RV is frequently found in the respiratory secretions of patients with CF and the impact of HRV-A appears higher than that of the other HRV types in patients with pulmonary exacerbations.

IgE-Mediated Immune Responses and Airway Detection of Aspergillus and Candida in Adult Cystic Fibrosis

The recovery of Aspergillus and Candida from the respiratory secretions of patients with cystic fibrosis (CF) is common. Their relationship to the development of allergic sensitization and effect on lung function has not been established. Improved techniques to detect these organisms are needed to increase knowledge of these effects. A 2-year prospective observational cohort study was performed. Fifty-five adult patients with CF had sputum monitored for Aspergillus by culture and real-time polymerase chain reaction and Candida by CHROMagar and carbon assimilation profile (API/ID 32C). Skin prick tests and ImmunoCAP IgEs to a panel of common and fungal allergens were performed. Lung function and pulmonary exacerbation rates were monitored over 2 years. Sixty-nine percent of patient sputum samples showed chronic colonization with Candida and 60% showed colonization with Aspergillus. There was no association between the recovery of either organism and the presence of specific IgE responses. There was no difference in lung function decline for patients with Aspergillus or Candida colonization compared with those without (FEV₁ percent predicted, P = .41 and P = .90, respectively; FVC % predicted, P = .87 and P = .37, respectively). However, there was a significantly greater decline in FEV1 and increase in IV antibiotic days for those sensitized to Aspergillus (FEV₁ decline, P = .03; IV antibiotics days, P = .03). Allergic sensitization is not associated with recovery of Candida or Aspergillus from the sputum of patients with CF. Aspergillus but not Candida sensitization is associated with greater lung function decline and pulmonary exacerbations.

Aspergillus fumigatus colonization in cystic fibrosis: implications for lung function?

Aspergillus fumigatus is commonly found in the respiratory secretions of patients with cystic fibrosis (CF). Although allergic bronchopulmonary aspergillosis (ABPA) is associated with deterioration of lung function, the effects of A. fumigatus colonization on lung function in the absence of ABPA are not clear. This study was performed in 259 adults and children with CF, without ABPA. A. fumigatus colonization was defined as positivity of >50% of respiratory cultures in a given year. A cross-sectional analysis was performed to study clinical characteristics associated with A. fumigatus colonization. A retrospective cohort analysis was performed to study the effect of A. fumigatus colonization on lung function observed between 2002 and 2007. Longitudinal data were analysed with a linear mixed model. Sixtyone of 259 patients were at least intermittently colonized with A. fumigatus. An association was found between A. fumigatus colonization and increased age and use of inhaled antibiotics. In the longitudinal analysis, 163 patients were grouped according to duration of colonization. After adjustment for confounders, there was no significant difference in lung function between patients colonized for 0 or 1 year and patients with 2–3 or more than 3 years of colonization (p 0.40 and p 0.64) throughout the study. There was no significant difference in lung function decline between groups. Although colonization with A. fumigatus is more commonly found in patients with more severe lung disease and increased treatment burden, it is not independently associated with lower lung function or more severe lung function decline over a 5-year period.

Lack of standardization in the procedures for mycological examination of sputum samples from CF patients: a possible cause for variations in the prevalence of filamentous fungi

Filamentous fungi and yeasts are increasingly isolated from respiratory secretions of patients with cystic fibrosis (CF), and persistent fungal colonization of the airways of such patients is thought to exacerbate lung damage. While many independent studies have identified Aspergillus fumigatus complex as the principal colonizing fungus in CF, increased awareness of the role of fungi in CF pathology coupled with improved mycological culture and identification methods have resulted in a number of other fungi being isolated and reported from CF sputum samples, including A. terreus, members of the Pseudallescheria boydii/Scedosporium apiospermum complex, Exophiala dermatitidis, Paecilomyces and Penicillium species. However, the range of fungal pathogens isolated and the relative prevalence of individual species vary widely between reports from different geographical CF centres, and as yet no standardized method for the mycological examination of CF sputum samples has been adopted. Here, we examine the potential contribution of the mycological methods employed to examine CF respiratory secretions relative to the variability in the fungal biota reported. The role of direct microscopic examination of respiratory samples and the impact of the culture conditions used on the detection of specific fungal pathogens are addressed, and the potential significance of isolation of yeast species from CF patient airways is discussed.

Exophiala (Wangiella) dermatitidis and cystic fibrosis – Prevalence and risk factors

The objective of this prospective study was to assess the prevalence of Exophiala dermatitidis in respiratory secretions of patients with cystic fibrosis (CF) and to identify risk factors for its presence. The results of all cultures performed over a 2-year period in non lung-transplant patients in our CF clinic were included in the study. Samples consisted of sputum (whenever possible) or deep pharyngeal aspirate after a session of physiotherapy. Specimens were inoculated onto Sabouraud gentamicin-chloramphenicol agar (SGCA) medium (Becton-Dickinson) and incubated at 35°C for 2 days and then at ambient temperature (15-25°C) for 3 weeks. The whole study group included 154 patients (mean age ± SD: 18.5 y ± 11.69). E. dermatitidis was isolated from 58 specimens (2.8%) of nine patients (5.8%) out of total of 2065 cultures prepared during the study period. All E. dermatitidis culture-positive patients were pancreatic insufficient and ≥12 y of age. Almost all (8/9) were homozygous for the F508 del mutation. Aspergillus fumigatus colonization and genotype seemed to be predisposing factors. No other significant characteristic was identified in this group, either in terms of predominant bacterial pathogen or treatment. A distinct comparative study performed over 3 months in our laboratory revealed that the use of SGCA yielded identical isolation rates of E. dermatitidis as erythritol-chloramphenicol agar (ECA).

Adesividade e purulência de secreções respiratórias: implicações no transporte mucociliar em pacientes com bronquiectasias

To analyze and compare the transport properties of respiratory secretions, classified by selected parameters, in individuals with bronchiectasis unrelated to cystic fibrosis. We collected mucus samples from 35 individuals with bronchiectasis unrelated to cystic fibrosis. The samples were first classified by their surface properties (adhesive or nonadhesive), as well as by their aspect (mucoid or purulent). We then tested the samples regarding relative transport velocity (RTV), displacement in a simulated cough machine (SCM), and contact angle (CA). For the proposed comparisons, we used ANOVA models, with a level of significance set at 5%. In comparison with nonadhesive samples, adhesive samples showed significantly less displacement in the SCM, as well as a significantly higher CA (6.52 ± 1.88 cm vs. 8.93 ± 2.81 cm and 27.08 ± 6.13º vs. 22.53 ± 5.92º, respectively; p < 0.05 for both). The same was true in the comparison between purulent and mucoid samples (7.57 ± 0.22 cm vs. 9.04 ± 2.48 cm and 25.61 ± 6.12º vs. 21.71 ± 5.89º; p < 0.05 for both). There were no significant differences in RTV among the groups of samples, although the values were low regardless of the surface properties (adhesive: 0.81 ± 0.20; nonadhesive: 0.68 ± 0.24) or the aspect (purulent: 0.74 ± 0.22; mucoid: The respiratory secretions of patients with bronchiectasis showed decreased mucociliary transport. Increased adhesiveness and purulence cause the worsening of transport properties, as demonstrated by the lesser displacement in the SCM and the higher CA.

Detection of herpes viruses in respiratory secretions of patients undergoing artificial ventilation

The significance of detection of herpes viruses in respiratory secretions of critically ill patients is controversial. The study aim was to determine the prevalence of herpes virus DNA in respiratory secretions in patients on artificial ventilation. Respiratory secretions taken thrice weekly from 174 patients in a tertiary center intensive therapy unit (ITU) were tested for herpes simplex virus (HSV) by nested PCR. Samples from 61 patients in ITU for 4 days or more were also tested for Epstein Barr Virus (EBV) and cytomegalovirus (CMV) using real-time PCR. HSV positivity increased with ITU stay with 18.6% admission samples positive, 32.5% day 2-5 samples, and 65.9% day 6-39 samples. Being HSV positive on admission did not influence mortality (9/27, 33.3% vs. 38/118, 32.2%) however, subsequently, mortality of those negative but becoming positive was higher than in those remaining negative (10/35, 29% vs. 5/24 21%). At least one sample was EBV positive in 61% and CMV positive in 19% of patients tested. Of 63 patients tested for all three viruses, 4 were positive for three viruses, 23 patients for two viruses, 24 for one virus and 12 were negative for all the above viruses. Detection of HSV, EBV and CMV is common in ITU patients. Becoming HSV positive while in ITU may increase mortality.

Stable Polymyxin B Susceptibility to Pseudomonas aeruginosa and Acinetobacter spp. despite Persistent Recovery of These Organisms from Respiratory Secretions of Patients with Ventilator-Associated Pneumonia Treated with This Drug

In a recent article, Lee et al. ([4][1]) reported the occurrence of an increase in MICs for polymyxin B during therapy in 3 of 16 patients treated with this drug for carbapenem-resistant Klebsiella pneumoniae infections. This report is very important, since polymyxins, polymyxin B and colistin, are