A worldwide systematic review and meta-analysis of bacteria related to antibiotic-associated diarrhea in hospitalized patients

INTRODUCTION

Antibiotic-associated diarrhea (AAD) is a major hospital problem and a common adverse effect of antibiotic treatment. The aim of this study was to investigate the prevalence of the most important bacteria that cause AAD in hospitalized patients.

MATERIALS AND METHODS

PubMed, Web of Science and Scopus databases were searched using multiple relevant keywords and screening carried out based on inclusion/exclusion criteria from March 2001 to October 2021. The random-effects model was used to conduct the meta-analysis.

RESULTS

Of the 7,377 identified articles, 56 met the inclusion criteria. Pooling all studies, the prevalence of Clostridioides (Clostridium) difficile, Clostridium perfringens, Klebsiella oxytoca, and Staphylococcus aureus as AAD-related bacteria among hospitalized patients were 19.6%, 14.9%, 27%, and 5.2%, respectively. The prevalence of all four bacteria was higher in Europe compared to other continents. The highest resistance of C. difficile was estimated to ciprofloxacin and the lowest resistances were reported to chloramphenicol, vancomycin, and metronidazole. There was no or little data on antibiotic resistance of other bacteria.

CONCLUSIONS

The results of this study emphasize the need for a surveillance program, as well as timely public and hospital health measures in order to control and treat AAD infections.

Peryton: a manual collection of experimentally supported microbe-disease associations

We present Peryton (https://dianalab.e-ce.uth.gr/peryton/), a database of experimentally supported microbe-disease associations. Its first version constitutes a novel resource hosting more than 7900 entries linking 43 diseases with 1396 microorganisms. Peryton's content is exclusively sustained by manual curation of biomedical articles. Diseases and microorganisms are provided in a systematic, standardized manner using reference resources to create database dictionaries. Information about the experimental design, study cohorts and the applied high- or low-throughput techniques is meticulously annotated and catered to users. Several functionalities are provided to enhance user experience and enable ingenious use of Peryton. One or more microorganisms and/or diseases can be queried at the same time. Advanced filtering options and direct text-based filtering of results enable refinement of returned information and the conducting of tailored queries suitable to different research questions. Peryton also provides interactive visualizations to effectively capture different aspects of its content and results can be directly downloaded for local storage and downstream analyses. Peryton will serve as a valuable source, enabling scientists of microbe-related disease fields to form novel hypotheses but, equally importantly, to assist in cross-validation of findings.

Vaccines in adults

The proportion of adult population has increased globally and the current projections indicate that, by 2050, the group of 60 years and older will represent 21.1%. There are now vaccines exclusively designed for adults and others that are applied in early life but need to be updated later in life. Vaccines for adults are not only based on their respective age group but are also linked to risk factors like occupation, life style, health situation, among others. At the same time, longevity brings with it a weakening of the immune response to vaccines, a process known as immunosenescence representing an increasing challenge to adequately protect this age group. For some time, WHO has been promoting the term "Vaccination through the life course" allowing for an extension of the vaccination vision and taking adults as an integral part into the national vaccination programs and calendars. There are several vaccine preventable diseases affecting adults, but those associated with influenza virus and pneumococcus are the ones that affect the largest age group. Several recommendations include, additionally, others to prevent diphtheria, tetanus, whooping cough, hepatitis A and B, meningococcus, chickenpox, measles, rubella, mumps, herpes zoster, human papilloma virus and others. There are still many challenges to overcome in order to fully include adults, particularly health personnel, and to make vaccines extensively valued as a prevention tool in order to achieve a healthy life.

Middle Meatus Bacteriology of Acute Rhinosinusitis in Patients after Irradiation of Nasopharynx

Background

Patients who undergo radiotherapy for nasopharyngeal carcinoma (NPC) tend to suffer from rhinosinusitis because irradiation causes damage to sinonasal tissue; however, their bacteriology is lacking in the literature. The aim of this study was to determine the bacteriology and antibiotic resistance in acute rhinosinusitis (ARS) of these patients.

Methods

We collected nasal purulent discharge for bacteriology and antibiotic susceptibility tests in irradiated NPC patients with ARS. Middle meatus discharge was aspirated for culture with endoscopic assistance.

Results

A total of 33 episodes of ARS were documented in 25 patients. Staphylococcus aureus comprised 42% of all aerobes. Thirty-six percents of aerobic isolates were Gram-negative bacilli. Peptostreptococcus micros and Veillonella spp were the most frequently isolated anaerobes.

Conclusion

The bacteriology in irradiated NPC patients with ARS was distinctive in the following: first, the most common pathogen was S. aureus; second, frequently isolated Gram-negative bacilli and anaerobes; and third, polymicrobial infections. The β-lactamase–producing pathogens were highly prevalent.

Antibiotic stewardship and empirical antibiotic treatment: How can they get along?

The aim of this review is to focus on the recent knowledge on antibiotic stewardship and empiric antibiotic treatment in cirrhotic patients. The application of antimicrobial stewardship (AMS) rules appears to be the most appropriate strategy to globally manage cirrhotic patients with infectious complications: indeed they represent a unique way to provide both early diagnosis and appropriate therapy in order to avoid not only antibiotic over-prescription but, more importantly, selection and spread of antimicrobial resistance. Moreover, cirrhotic patients must be considered "frail" and susceptible to healthcare associated infections: applying AMS policies would assure a cost reduction and thus contribute to the improvement of public health strategies.

Tracking the Remodeling of SNOMED CT's Bacterial Infectious Diseases

SNOMED CT's content undergoes many changes from one release to the next. Over the last year SNOMED CT's Bacterial infectious disease subhierarchy has undergone significant editing to bring consistent modeling to its concepts. In this paper we analyze the stated and inferred structural modifications that affected the Bacterial infectious disease subhierarchy between the Jan 2015 and Jan 2016 SNOMED CT releases using a two-phased approach. First, we introduce a methodology for creating a human readable list of changes. Next, we utilize partial-area taxonomies, which are compact summaries of SNOMED CT's content and structure, to identify the "big picture" changes that occurred in the subhierarchy. We illustrate how partial-area taxonomies can be used to help identify groups of concepts that were affected by these editing operations and the nature of these changes. Modeling issues identified using our two-phase methodology are discussed.

Cell Wall-Deficient Bacteria as a Cause of Infections: A Review of the Clinical Significance

Cell wall-deficient bacteria (CWDB) are pleomorphic bacterial forms. These atypical organisms may occur naturally or they can be induced in the laboratory. Their presence has been known about for over a century, but a definite link to clinical disease outcomes has not been demonstrated. A number of case reports and laboratory studies suggest some disease associations, however. Considerable controversy surrounds the true relevance of CWDB to disease; there is a widespread belief that they may represent a response by the walled organism to adverse extracellular conditions like antibiotic pressure. This review looks at studies published between 1934 and 2003, which were identified by Dialog DataStar using the key words ‘cell wall deficient bacteria and clinical significance and infections’ and by further scanning the reference list at the end of the papers retrieved. We conclude that the evidence for the clinical significance of CWDB in disease is not compelling.

PREVALENCE OF BACTERIAL RESISTANCE IN HOSPITALIZED CIRRHOTIC PATIENTS IN SOUTHERN BRAZIL: A NEW CHALLENGE

BACKGROUND & AIMS

An increased frequency of infections by multiresistant bacteria has been described in hospitalized patients. The aim of this study was to evaluate the bacterial resistance profile in cirrhotic patients.

METHODS

This is a retrospective observational study. We assessed the antimicrobial susceptibility of 5,839 bacterial isolates from patients with and without cirrhosis. Regarding the multidrug resistance, we evaluated 4,505 bacterial isolates from 2,180 patients.

RESULTS

Two hundred and fifty-one patients had cirrhosis (mean age 57.6 ± 11 years; 61.8% were male, 47.8% of cases associated with hepatitis C virus). Of the isolates of patients with and without cirrhosis, 174/464 (37.5%) and 1,783/4,041 (44.1%) were multiresistant, respectively (p = 0.007). E. coli was the most common multiresistant bacteria in both groups. Approximately 20% of E. coli and Klebsiella sp. isolates were ESBL-producers and 44% of S. aureus isolates were methicillin-resistant in cirrhotic patients. In cirrhotic patients admitted to the emergency department, hospital ward, and intensive care unit, 28.3%, 50% and 40% had multiresistant isolates, respectively. In patients with and without cirrhosis, 36.2% and 33.5% of isolates were resistant to third-generation cephalosporins, respectively.

CONCLUSIONS

The empirical treatment of infections in hospitalized patients using broad-spectrum antibiotics should consider the observed pattern of bacterial resistance.

Surgical-Site Infection Rates and Risk Factor Analysis in Coronary Artery Bypass Graft Surgery

Background:

The Victorian Infection Control Surveillance Project (VICSP) is a multicenter collaborative surveillance project established by infection control practitioners. Five public hospitals contributed data for patients undergoing coronary artery bypass graft (CABG) surgery.

Objective:

To determine the aggregate and comparative interhospital surgical-site infection (SSI) rates for patients undergoing CABG surgery and the risk factors for SSI in this patient group.

Method:

Each institution used standardized definitions of SSI, risk adjustment, and reporting methodology according to the National Nosocomial Infections Surveillance System of the Centers for Disease Control and Prevention. Data on potential risk factors were prospectively collected.

Results:

For 4,474 patients undergoing CABG surgery, the aggregate SSI rate was 7.8 infections per 100 procedures (95% confidence interval [CI95], 7.0-8.5), with individual institutions ranging between 4.5 and 10.7 infections per 100 procedures. Multivariate risk factor analysis demonstrated age (odds ratio [OR], 1.02; CI95, 1.01-1.04; P < .001), obesity (OR, 1.8; CI95, 1.4-2.3; P < .001), and diabetes mellitus (OR, 1.6; CI95, 1.2-2.1; P < .001) as independent predictors of SSI. Three hundred thirty-four organisms were isolated from 296 SSIs. Of the total SSIs, methicillin-resistant Staphylococcus aureus was isolated from 32%, methicillin-sensitive S. aureus from 24%, gram-negative bacilli (eg, Enterobacter and Escherichia colt) from 18%, and miscellaneous organisms from the remainder.

Conclusion:

We documented aggregate and comparative SSI rates among five Victorian public hospitals performing CABG surgery and defined specific independent risk factors for SSI. VICSP data offer opportunities for targeted interventions to reduce SSI following cardiac surgery.

[Anaerobic nonclostridial infection of pelvis: classification and its practical application]

Anaerobic nonclostridial infection of pelvis are analysed in 89 patients that were on treatment in the department of festering surgery in 1999-2012 years. Clinical classification of disease is offered and it is applied in practice for dividing of research array into clinically-morphological groups with the aim of the differentiated going near a surgical treatment.

Design and evaluation of a bacterial clinical infectious diseases ontology

With antimicrobial resistance increasing worldwide, there is a great need to use automated antimicrobial decision support systems (ADSSs) to lower antimicrobial resistance rates by promoting appropriate antimicrobial use. However, they are infrequently used mostly because of their poor interoperability with different health information technologies. Ontologies can augment portable ADSSs by providing an explicit knowledge representation for biomedical entities and their relationships, helping to standardize and integrate heterogeneous data resources. We developed a bacterial clinical infectious diseases ontology (BCIDO) using Protégé-OWL. BCIDO defines a controlled terminology for clinical infectious diseases along with domain knowledge commonly used in hospital settings for clinical infectious disease treatment decision-making. BCIDO has 599 classes and 2355 object properties. Terms were imported from or mapped to Systematized Nomenclature of Medicine, Unified Medical Language System, RxNorm and National Center for Bitechnology Information Organismal Classification where possible. Domain expert evaluation using the "laddering" technique, ontology visualization, and clinical notes and scenarios, confirmed the correctness and potential usefulness of BCIDO.

Vaccine update: the latest from ACIP

ACIP has combined 2 vaccine schedules into a single schedule for infants, children, and adolescents. It also recommends the Tdap vaccine for those ≥ 65 years and the pneumococcal conjugate vaccine for adults at high risk.

Infectious diseases in Poland in 2011

The aim of the study was assessment of the epidemiological situation of infectious and parasitic diseases in Poland in 2011 MATERIALS AND METHODS: The main source of data to develop the statistical overview was the annual bulletin "Infectious diseases in Poland in 2011," and "Vaccinations in Poland in 2011,"/NIPH-NIH, CSI, 2011 and information contained in the articles of epidemiological journal in which authors depth discussion of the epidemiological situation of 27 diseases or groups of diseases. Data on deaths are based on the statements of the Department of the Central Statistical Office of Demographic Studies.

RESULTS

Upper respiratory tract infection classified as "influenza and influenza-like illness" in 2011, were reported in a total number of 1,156,357 cases, which was an 108.0% increase of incidence as compared with 2010. and in relation to the median of the years 2005 - 2009 of 205.9%. In 2011, food infections dominated among the bacterial infections caused by Salmonella, with the continuing decline of incidence and fraction of salmonellosis among other etiologies. Among the diseases that can be prevented by vaccination it was reported 30.7% increase in the incidence of pertussis. In relation to the median of the years 2005-2009 is a decrease of 16.9%. A downward trend in the incidence of mumps was maintained. As compared to 2010, the incidence decreased by 7.0%. When compared to the median of the years 2005 to 2009 the decline was 38.3%. In relation to the median of the years 2005-2009 there have been a decrease of the number of rubella cases by 67.7% and there have been no reported cases of congenital rubella. A further decline in the incidence of invasive disease caused by H. influenzae was observed. The incidence of tuberculosis in 2011 increased as compared to the previous year from 19.7 to 22/100,000 in respect to all forms of tuberculosis, and pulmonary tuberculosis from 18.3 to 20.5/100,000. The number of newly diagnosed HIV-infected persons also increased. In 2011 it was reported 1,105 cases (2.87/100,000), compared with the previous year, an increase of 14.8%. In 2011, there were reported 221 cases (0.57/100,000) of tick-borne encephalitis, i.e. by 25.5% less than in the previous year, the incidence of viral meningitis decreased by 11.8%. In 2011, there were no cases of especially dangerous infectious diseases: plague, anthrax, diphtheria, polio, rabies and viral hemorrhagic fevers besides dengue, of which 5 cases acquired in endemic areas were reported to the epidemiological surveillance. Due to infectious and parasitic diseases in 2011, died in Poland 3,408 people total. The share of deaths from these causes in the total number of deaths was 0.91%, and the mortality rate--8.8 per 100,000 population, 52.0% of all deaths were due to sepsis.

Bacteria and Candida yeasts in inflammations of the oral mucosa in children with secondary immunodeficiency

BACKGROUND

Oral microbial flora and a damaged oral mucosa may increase the risk of bacteriemia, fungemia and complications in immunocompromised patients.

AIM OF THE STUDY

Assessment of presence: bacteria and Candida spp. in different oral lesions, and the incidence of bacteremia in the case of a damaged mucosa in transplant recipients and patients receiving anti-tumour chemotherapy.

MATERIAL AND METHOD

Forty-five patients – 18 months to 18 years of life, were included (20 – organ recipients, 14– anti-tumour chemotherapy, 11 – control group). Clinical, oral mucosa examination focused on the type, severity and site of lesions, and microbiology assessed the presence of bacteria and fungi in the material from lesions. Blood cultures were performed in ten immunocompromised patients with manifestations of systemic infection. The control material consisted of blood cultures made prior to the onset of oral lesions and after 4–6 weeks following their remission in a diagnosed bacteremia. The statistical analysis was performed.

RESULTS

In the subjects with secondary immunodeficiency, among other coagulase-negative Staphylococcus (CoNS), Candidia spp. were more frequent. In cancer patients, mucositis was associated with Candida spp., Streptococcus spp. Organ recipients with stomatitis exhibited the presence of CoNS, Streptococcus viridians and other. Oral lesions in the control group contained Haemophilus parainfluenzae, Neisseria spp. and Staphylococcus aureus. In 30% of immunocompromised patients, oral lesions were accompanied by bacteremia.

CONCLUSIONS

A correlation has been found between oral lesions and the presence of S. aureus in patients without secondary immunodeficiency, and of CoNS, Enterococcus spp., Candida spp. in immunocompromised patients.

[Infectious diseases in Poland in 2010]

The purpose of the study is assessment of the epidemiological condition of infectious diseases in Poland in 2010, especially in comparison with 2009 and the years 2004-2008.

MATERIAL AND METHODS

The evaluation of the epidemiological situation of infectious diseases in Poland was based on analysis of data: published in the annual bulletin "Infectious diseases in Poland in 2010" and "Vaccinations in Poland in 2010"/NIPH-NIH, GIS, 2011, the data contained in 27 articles prepared for publication in the Chronicle of epidemiology for 2010; data of Demographic Research Department of the central Statistical Office (GUS) for deaths from infectious and parasitic diseases registered in 2010 and selected earlier years.

RESULTS

The most common group of diseases were respiratory diseases--despite a significant relative to 2009, a decrease of 49.1% of cases of influenza and flu-like disease. Still a major epidemiological problem in Poland is food poisoning and foodborne infections--despite the downward trend in the incidence of salmonellosis. In 2010, 9 732 cases were reported, and the incidence of salmonellosis was 25.5 to 100 000. There was an increase of gastro-intestinal infections, caused by viruses, compared to the median of the years 2004-2008 by 58.1%. Particularly important is epidemiological surveillance of the diseases covered by the immunization program. Their situation can be assessed as satisfactory. However, special attention is paid to the spread of viral hepatitis B and C, in which there was an increased incidence, respectively, by 10% and 2%. Decreased by 5.3% the number of newly registered cases of HIV infection. In 2010, total 3 044 people died in Poland due to infectious and parasitic diseases. The share of deaths from these diseases in the total number of deaths in Poland (378 478) was 0.80% - 8 deaths per 100 000. and were comparable to the data for 2009 In the last decade increased mortality due to infectious diseases was observerd, mainly due to the increase in diagnosed cases of sepsis.

CONCLUSIONS

Infectious diseases, although a small part in the overall statistics of deaths, have not ceased to be a serious public health problem. As regards epidemiological surveillance is necessary to continue the legislative work on improving its sensitivity and increase microbiologically confirmed diagnoses.

[Infected lesions of diabetic foot]

The diabetic foot lesions are the result of a complex set of factors including peripheral neuropathy, trauma, joint deformities and perfusion abnormalities. The foot becomes vulnerable and insensitive to minor injuries caused by excessive pressure, mechanically or minimum thermal insults that can determine the primum movens of a foot ulcer. Due to the trauma, the subcutaneous tissues are exposed to bacterial colonization. Therefore, the wound can develop an infection. So, the first step in the treatment of the lesion is the evaluation of tissue damage, in order to guide therapy and prognosis. Wagner's classification, used by over 25 years, is still one of the best known systems of lesion classification; however, it is giving way to the most recent Texas's classification. However, in both systems infection have a minority role. Therefore, the Infectious Diseases Society of America has developed a classification system that divides infections in mild, moderate and severe. The purpose of this classification is to recognize the severe patients because they require immediate hospitalization, parenteral antibiotic therapy and specific instrumental examinations.

Biological agents as occupational hazards - selected issues

There are two main groups of biological agents regarded as occupational hazards: allergenic and/or toxic agents forming bioaerosols, and agents causing zoonoses and other infectious diseases. Bioaerosols occurring in the agricultural work environments comprise: bacteria, fungi, high molecular polymers produced by bacteria (endotoxin) or by fungi (β-glucans), low molecular secondary metabolites of fungi (mycotoxins, volatile organic compounds) and various particles of plant and animal origin. All these agents could be a cause of allergic and/or immunotoxic occupational diseases of respiratory organ (airways inflammation, rhinitis, toxic pneumonitis, hypersensitivity pneumonitis and asthma), conjunctivitis and dermatitis in exposed workers. Very important among zoonotic agents causing occupational diseases are those causing tick-borne diseases: Lyme borreliosis, anaplasmosis, babesiosis, bartonellosis. Agricultural workers in tropical zones are exposed to mosquito bites causing malaria, the most prevalent vector-borne disease in the world. The group of agents causing other, basically not vector-borne zoonoses, comprises those evoking emerging or re-emerging diseases of global concern, such as: hantaviral diseases, avian and swine influenza, Q fever, leptospiroses, staphylococcal diseases caused by the methicillin-resistant Staphylococcus aureus (MRSA) strains, and diseases caused by parasitic protozoa. Among other infectious, non-zoonotic agents, the greatest hazard for health care workers pose the blood-borne human hepatitis and immunodeficiency viruses (HBV, HCV, HIV). Of interest are also bacteria causing legionellosis in people occupationally exposed to droplet aerosols, mainly from warm water.

[Biofilms of pathogenic bacteria and their role in chronization of infectious process. The search for the means to control biofilms]

The role of biofilms in the environment and in the hosts of pathogenic bacteria has recently attracted much attention of researchers. Microorganisms form biofilms at any biotic and abiotic surfaces and thereby cause serious problems in medical practice and other areas of human activity. Biofilms have been shown to be pathogenetic factors responsible for chronization of infectious process. The data are presented illustrating ubiquitous nature of biofilms, their structural and functional characteristics, and modern methods for the study of microbial communities. The discussion is focused on the role of biofilms in chronization of infectious process, enhanced resistance of biofilm organisms to antibiotics and its underlying mechanisms. Approaches to the search for new means for biofilm control during chronic infections are considered.

The use of a dermal substitute to preserve maximal foot length in diabetic foot wounds with tendon and bone exposure following urgent surgical debridement for acute infection

In this study, we evaluated the utility of a dermal substitute for preserving maximal foot length after urgent surgical debridement. Patients referred to our Diabetic Foot Center with foot lesions were assessed for sensory-motor neuropathy, infection and critical limb ischaemia. The presence of acute foot infection indicated the need for immediate surgical debridement. The degree of amputation, if necessary, was based on the amount of apparently non infected vital tissue. When vital tendon/bone tissue remained exposed, the lesion was covered with a dermal substitute. From January to December 2008, 393 patients underwent surgical treatment for diabetic foot syndrome; 30 patients underwent immediate surgical debridement resulting in exposed tendon and/or bone tissues. An average of 4.4 +/- 2.1 days following surgical debridement, all 30 patients underwent dermal regeneration template grafting to cover-exposed healthy tendon and bone tissues, instead of achieving primary wound closure with a proximal amputation. After 21 days, a skin graft was performed. Complete wound healing occurred in 26 patients (86.7%). In these patients, the amputation level was significantly more distal (P < 0.003) with respect to that potentially required for immediate wound closure. The average healing time was 74.1 +/- 28.9 days. Four patients underwent a more proximal amputation. No patients underwent major amputation. The use of the dermal substitute for treating exposed tendon and bone tissues allowed timely wound healing and preserved maximal foot length. Continued follow-up will allow assessment of long-term relapse and complication rates. Such treatment could constitute part of the comprehensive management of diabetic wounds.

Epidemiological, clinical and microbiological profile of infective endocarditis in a tertiary hospital in the South-East Anatolia Region

OBJECTIVES

We aimed to evaluate epidemiological, clinical, and microbiological features of infective endocarditis (IE) in a tertiary university hospital.

STUDY DESIGN

The study included 72 patients (31 women, 41 men; mean age 45+/-16 years; range 18 to 80 years) who were diagnosed as having definite IE, according to the modified Duke criteria, between 2004 and 2007. Data were reviewed on age, sex, underlying heart disease, predisposing conditions for bacteremia, echocardiographic and microbiological findings, treatment, complications, and mortality.

RESULTS

Infective endocarditis developed on a native valve in 47 (65.3%), a mechanical prosthetic valve in 21 (29.2%), and a pacemaker in two cases. The location of IE could not be determined in two cases (2.8%). Rheumatic heart disease (36.1%) was the most common preexisting valvular abnormality. The mitral valve was the most commonly affected valve in both native valves (43.1%) and prosthetic valves (13.9%). The most frequent symptom was fever (n=60, 83.3%). Electrocardiography showed abnormal findings in 24 cases (33.3%). Transthoracic and/or transesophageal echocardiography showed a vegetation in 63 cases (87.5%), moderate or severe mitral regurgitation in 41 cases (56.9%), aortic regurgitation in 21 cases (29.2%), and tricuspid regurgitation in 29 cases (40.3%). Staphylococci (26.4%) and streptococci (22.2%) were the most common causative agents. Cultures were negative in 26 cases (36.1%). Twenty patients (27.8%) underwent surgical treatment. Congestive heart failure (n=23, 31.9%) and cerebrovascular accidents (n=10, 13.9%) were the major complications. In-hospital mortality occurred in 11 cases (15.3%).

CONCLUSION

Our data reflect epidemiological, clinical, and microbiological profile of IE in a tertiary hospital located in the Southeastern Anatolia.

[Histopathologic diagnosis of infectious loosening of joint prostheses]

To optimize the reliability of histopathological criteria for periprosthetic infection, 110 tissue specimens from joint prostheses were analyzed with quantification of the inflammatory cells and immunohistochemical typing of lymphocytes and plasma cells. As reported in the literature the density of granulocytic infiltration was the most sensitive marker of periprosthetic infection with an accuracy of 84%, a sensitivity of 91%, a specificity of 81%, a positive predictive value of 67%, and a negative predictive value of 95%, using the mostly favored limit value of 5 granulocytes per HPF. T lymphocytes were also found to a high degree in cases of aseptic loosening. In contrast, B lymphocytes were predominantly seen in cases with periprosthetic infection. For B lymphocytes an accuracy of 80% and a sensitivity of 79% were calculated and for plasma cells an accuracy of 75% and a sensitivity of 79%. Our data suggest that the quantification of granulocyte, B-cell, and plasma cell infiltrates is an important parameter for verifying the diagnosis of periprosthetic infection.

Infection and sudden unexpected death in infancy: a systematic retrospective case review

BACKGROUND

The cause and mechanism of most cases of sudden unexpected death in infancy (SUDI) remain unknown, despite specialist autopsy examination. We reviewed autopsy results to determine whether infection was a cause of SUDI.

METHODS

We did a systematic retrospective case review of autopsies, done at one specialist centre between 1996 and 2005, of 546 infants (aged 7-365 days) who died suddenly and unexpectedly. Cases of SUDI were categorised as unexplained, explained with histological evidence of bacterial infection, or explained by non-infective causes. Microbial isolates gathered at autopsy were classified as non-pathogens, group 1 pathogens (organisms usually associated with an identifiable focus of infection), or group 2 pathogens (organisms known to cause septicaemia without an obvious focus of infection).

FINDINGS

Of 546 SUDI cases, 39 autopsies were excluded because of viral or pneumocystis infection or secondary bacterial infection after initial collapse and resuscitation. Bacteriological sampling was done in 470 (93%) of the remaining 507 autopsies. 2079 bacteriological samples were taken, of which 571 (27%) were sterile. Positive cultures yielded 2871 separate isolates, 484 (32%) of which showed pure growth and 1024 (68%) mixed growth. Significantly more isolates from infants whose deaths were explained by bacterial infection (78/322, 24%) and from those whose death was unexplained (440/2306, 19%) contained group 2 pathogens than did those from infants whose death was explained by a non-infective cause (27/243, 11%; difference 13.1%, 95% CI 6.9-19.2, p<0.0001 vs bacterial infection; and 8.0%, 3.2-11.8, p=0.001 vs unexplained). Significantly more cultures from infants whose deaths were unexplained contained Staphylococcus aureus (262/1628, 16%) or Escherichia coli (93/1628; 6%) than did those from infants whose deaths were of non-infective cause (S aureus: 19/211, 9%; difference 7.1%, 95% CI 2.2-10.8, p=0.005; E coli: 3/211, 1%, difference 4.3%, 1.5-5.9, p=0.003).

INTERPRETATION

Although many post-mortem bacteriological cultures in SUDI yield organisms, most seem to be unrelated to the cause of death. The high rate of detection of group 2 pathogens, particularly S aureus and E coli, in otherwise unexplained cases of SUDI suggests that these bacteria could be associated with this condition.

Necrotizing fasciitis: A life-threatening clinical disorder in uncontrolled type 2 diabetic patients

We presented 23 patients with necrotizing fasciitis (NF), 15 of whom had uncontrolled diabetes mellitus (DM), for risk factors, clinical signs, laboratory findings and prognosis during the period 1998 and 2006 in Istanbul. A hospital incidence of NF was 14.2/100,000 admissions. Other risk factors were obesity in 9 and recent surgical trauma in 10 patients. The mean age of the patients with DM was higher than that of the patients with non-DM (58.6+/-12.8 vs 43.0+/-17.2 years, p=0.028). The most frequently isolated microorganisms from tissue cultures were Escherichia coli, Klebsiella pneumoniae and Group A streptococci. Of the 23 patients, 9 (39%), of whom 8 had DM, died between 2 and 29 days after admission. The mortality rate and length of hospitalization were longer in diabetic patients than in others (p=0.02 and p=0.286, respectively). The mean blood glucose levels and HbA1C were higher in non-survival group than in survival group (195.6+/-41.5 vs 133.7+/-22.1 and 10.6 vs 7.4) (p=0.04, r=0.39 and p=0.03, r=0.50, respectively). In the univariate analysis, the hospitalization time (r=0.72), white blood cell count (r=0.52) and surgical debridement count (r=0.47) were found to be prognostic risk factors. Our results showed that NF is a very serious life-threatening disorder in especially diabetic patients with bad metabolic control.

Acute bacterial meningitis at the 'Complexe Pédiatrique' of Bangui, Central African Republic

To precis the aetiologies of children meningitis and the susceptibility to antibiotics of bacteria responsible for meningitis in Bangui, we conducted a prospective study between October 2004 and September 2005, at the 'Complexe Pédiatrique de Bangui', Central African Republic (CAR). Children from 1 day to 16 years with suspected meningitis and who underwent a lumbar puncture were enrolled. Gram staining, culture on chocolate blood medium, cell count, biochemistry (protein level, glucose ratio), capsular antigen detection were performed for each cerebrospinal fluid. MICs were determined by the E-test method. Four hundred and seventeen patients were enrolled during the study period; 130 were proven acute bacterial meningitis and 37 probable bacterial meningitis. Among proven bacterial meningitis, Streptococcus pneumoniae was the most common organism responsible for meningitis (62 cases, 48%) followed by Haemophilus influenzae (46 cases, 35%) and by Neisseria meningitidis and Salmonella sp. (8 cases, 6% each). Ninety-four percent and 96% of S. pneumoniae strains tested remain susceptible to benzylpenicilline and chloramphenicol, respectively. A beta-lactamase was detected in 92% of H. influenzae strains tested. However, MICs 50% and 90% for amoxicillin were found to be 1 and 4 mg/l, respectively and 33% of these strains were resistant to chloramphenicol. The global mortality rate was 35% (59/167). This mortality rate was 47% for S. pneumoniae, 33% for H. influenzae, 62% for Salmonella sp. and 13% for N. meningitidis. The probabilistic treatment with ampicillin and chloramphenicol usually administered for children meningitis in Bangui must be reconsidered particularly in cases of H. influenzae meningitis. It is of importance to reduce the presentation delays of children with suspected meningitis in Bangui. The H. influenzae b immunization would allow a dramatic reduction of meningitis cases and deaths in Central African children.

[Child acute otitis media]

Most frequent complication of children upper respiratory tract infections, acute otitis media is the leading cause of bacterial infections and one of the leading causes of antibiotic prescriptions. Under the combined effect of Prevenar immunization and the reduction of the use of antibiotics in France, the highly resistant strains of pneumococci (those which posed therapeutic problems) decreased moreover of the three quarter. Non typable H. influenzae became the main bacteria responsible of AOM, and resistance to the beta-lactams by change of penicillin binding proteins is an emergent problem in France. The diagnosis of purulent OMA is based on a triad: recent onset functional (otalgia) and generals (fever) signs, middle ear effusion and tympanic membrane inflammation. The official French guidelines suggest prescribing antibiotics (amoxicillin-acid clavulanate-cefpodoxime proxetil) only for purulent acute otitis media diagnosed in an unquestionable way, systematically in the child of less than two years, only for the most symptomatic forms after this age, while making use of the history and the clinical and bacteriological correlations to choose antibiotic.

Pneumonies acquises sous ventilation mécanique: suivez les recommandations!

OBJECTIVES

To compare the clinical outcomes and the causative pathogens of early-onset and late-onset ventilator-associated pneumonia (VAP) diagnosed by bronchoalveolar lavage (BAL).

STUDY DESIGN

Prospective, observational, epidemiological study.

PATIENTS AND METHODS

During a 7-years period, all first episodes of VAP were prospectively included. Diagnosis was confirmed by a BAL with a threshold of 10(4) cfu/ml. Late-onset pneumonia was defined if occurred after the seventh day after mechanical ventilation.

RESULTS

One hundred and thirteen VAP were studied. Fifty were early-onsets and 63 late-onsets. Thirty-four per cent of early-onset VAP and 73% of late-onset VAP were due to potential multiresistants pathogens. Pseudomonas aeruginosa was the most commonly isolated bacteria both in early-onset and late-onset VAP (16 and 39% respectively). Morbidity and mortality (29 vs 29%, ns) were not statically different between the two groups (early-onset and late-onset VAP).

CONCLUSION

In our study, both early-onset and late-onset VAP were mainly caused by potentially multiresistants bacteria, most commonly Gram negative bacilli. Even for early VAP, clinicians should be aware about all risk factors for potentially multiresistants pathogens and not only the delay of onset of the VAP episode.

FACTORS AFFECTING IMPLANT RETENTION IN INFECTED JOINT REPLACEMENTS

BACKGROUND

There is no standard treatment for infected joint replacements. The options available are varied, and treatment choices may pose problems in relation to both efficacy and cost-effectiveness.

METHODS

A retrospective review of 73 patient records identified in our departmental audit database as infected joint replacements treated at Dunedin Hospital between 1990 and 2000 was carried out. The findings were analysed in terms of outcome of primary treatment, final outcome including prosthesis retention and bacteriology.

RESULTS

Of the 73 patients (50 hips and 20 knees), the majority (69%) were managed by primary surgical debridement followed by intravenous antibiotics but about one-third (34%) lost their implants because of infection. Retention of implants was higher in acute infections (85-100%) as opposed to late infections (20-50%). The microbiological analysis showed that Staphylococcus and Streptococcus caused the majority (76%) of infections.

CONCLUSION

In our series, a patient with an infected joint replacement had an approximately similar 30% chance of retaining the original prosthesis, undergoing a successful revision and having no implants in situ at the end of treatment.

[Proper use of antibiotics: a prospective study on the use of linezolid in a French university hospital]

AIM OF THE STUDY

To describe clinical use of a new antibiotic: linezolid, in a French university hospital, on a population of patients different from the one studied during the clinical trials for the marketing authorisation.

PATIENTS AND METHODS

An observational, prospective cohort study performed in patients treated by linezolid between November 2005 and June 2006 at Saint André hospital (Bordeaux University Hospital). The following data were collected: sources of infection, isolated pathogens, patient's background, antibiotherapy strategies, duration of therapy and evolution.

RESULTS

Fifty patients (intensive care, internal medicine) were included. The absence of local guidelines on proper use of linezolid led to various prescriptions as well in infections listed in the marketing authorisation: nosocomial pneumonia and ventilator associated pneumonia (48%), skin and soft tissue infections (11%), as in endocarditis (7%), intra-abdominal infections (13%), bone and joint infections (2%), catheter infections (13%) and febrile neutropenic patients (6%). The main justification for using linezolid was worsening renal dysfunction (66%), which contra indicated glycopeptides use. Isolated pathogens were for the major part staphylococcus.

CONCLUSION

In the context of proper use of antibiotics, it would be advisable to add new recommendations on the use of linezolid to the hospital's antibiotherapy guide which would constitute a tool for the prescribing clinicians, and to re-evaluate the impact during a second evaluation.

Characterization of the Organ Donor With Bacteremia

INTRODUCTION

The presence of bloodstream infection in the donor is a common finding that could be transmitted to the recipient. To safely expand the donor pool, we examined its relevance.

MATERIALS AND METHODS

We described the clinical characteristics of organ donors grafted in our center between 1997 and 2006 who had bacteremia detected in blood cultures obtained during organ procurement.

RESULTS

Among 1353 organ donors, 75 were non-heart-beating donors type II and the others brain-dead donors. Only 186 donors (14%) showed bacteremia during retrieval. This mean age was 49.8 years (range 12 to 86 years, SD 18) including 63% men. Causes of death were cerebrovascular accident in 60%; craneoencephalic trauma, 25%; and other causes, 15%. The average length of the intensive care unit stay was 3 days (interquartile range: 2 to 7 days). Twenty-nine percent of donors presented previous infectious complications (90% from respiratory origin). The most prevalent pathogen isolated in blood cultures was coagulase negative Staphylococci (46,2%), followed by S aureus (15%), Streptococcus group viridans (9.1%), enterobacteria (9%), Enterococcus faecalis (7.5%) and gram-negative bacilli nonfermentative (6.2%). In 3.1%, the bloodstream infections were polymicrobial. The bronchial aspiration cultures were positive in 50% of cases and the urine culture in 8,6%. In 17% of donors the isolated microorganism was coincident between blood and bronchial cultures. Pseudomonas spp and S aureus were more common than the others (P = .004 and P = .058, respectively).

CONCLUSIONS

The incidence of bacteremia in our cohort was 14%. The respiratory tract was the most common clinical focus. Pseudomonas spp or S aureus isolated in bronchial cultures are risk factors to develop bacteremia. According to these findings, it is important to start specific antibiotics against those microorganisms in the donor and the recipients.

[Bacteriological aspects of osteitis in a university hospital]

INTRODUCTION

The aim, of our retrospective study, was to determine the epidemiological and susceptibility profile of bacterial osteitis isolates in the Rabat Mohammed V Military Hospital, to optimize the probabilistic antibiotherapy.

MATERIALS AND METHODS

A study was made from August 2004 to December 2005. All the positive specimen for the etiologic diagnosis of osteitis and osteoarthritis were included.

RESULTS

During this period, 85 osteitis cases were documented. 123 isolates were collected. 31 cases of osteitis allowed for the isolation of at least 2 bacteria (36.5%). The Gram positive cocci rate was 54.5%, the Gram negative bacilli rate 39.8%, and the Gram positive bacilli rate 5.7%. The distribution by groups was staphylococcus spp 46.4%, enterobacteriaceae 25.2% and non-fermenting Gram negative bacilli 12.9%. The most frequently isolated species were Staphylococcus aureus (23,6%) followed by Pseudomonas aeruginosa (8.9%), and Klebsiella pneumoniae (5.7%). All the S. aureus isolates were susceptible to oxacillin and 30.8% of the coagulase negative staphylococci were resistant. The enterobacteriaceae resistance rates were 64.5% for clavulanic acid-amoxicillin and 16% for third generation cephalosporin and ciprofloxacin. The non-fermenting Gram negative bacilli resistance rate was 37.5% for ceftazidim, 62.5% for ticarcillin, and 12.5% for imipenem.

CONCLUSION

Our results show the potential efficient therapy for community osteitis, using the traditional association: methicillin-aminosides and oral relay with fluoroquinolones. In nosocomial osteitis, the antibiotherapy must be modulated according to the identification and an antibiogram.

Seeking the Factors Predisposing to Local Skin Inflammatory State Development in Children with Type 1 Diabetes (T1DM) Treated with Continuous Subcutaneous Insulin Infusion (CSII)

The often CSII treatment complication is local skin infection. The aim of the study was to analyze chosen factors predisposing to this complication.

MATERIAL AND METHODS

We observed 40 children aged 1.9-15.6, suffering from diabetes for 0.1-12 and treated by CSII for 0.01-4.4 years in whom HbA1c, BMI, injection site and catheter insertion duration, catheter colonization, skin flora and Staphylococcus aureus carrier state were analyzed. The catheter cultures were prepared with Maki method. The skin and nasal vestibule swab were taken to detect local flora.

RESULTS

In the culture of 43 catheters (Maki method) a positive growth (>10 cfu) was detected in 9 (21%), homogeny culture of coagulase-negative staphylococci in 7 and mixed culture (both S.epidermidis and S.aureus) in two cases. Skin inflammation of the injection site was observed in a total of 10 children (25%), in two of whom catheter culture was positive. A statistically significant relation between the presence of bacteria in the catheter and on the skin around the injection site was found. Among the examined parameters, the relation between the catheter colonization and HbA1c, female sex and BMI were observed.

CONCLUSIONS

Metabolic control, female sex and BMI influence the development of a skin inflammatory state in patients treated with CSII. S.aureus carrier state has no impact either on catheter colonization or the development of an infection. However, bacteria skin occurrences can predispose to catheter colonization by the strain as well as to developing an inflammation.

Infections in Patients With End-stage Liver Disease

Infections in patients with end-stage liver disease (ESLD) are an important cause of morbidity and mortality in these patients. Abnormalities in their natural defense mechanisms, alterations in the enteric flora and the growing utilization of invasive procedures increase the risk of infections in these patients. Common bacterial infections in ESLD patients include spontaneous bacterial peritonitis, urinary tract infections, community-acquired pneumonia, dermatologic infections, and bacteremia. Viral infections such as influenza can have a devastating course in ESLD patients. Hepatitis B and C are now among the most common causes of ESLD. They also present an important therapeutic challenge. As patients with human immunodeficiency virus are surviving longer, ESLD due to hepatitis C is now emerging as a leading cause of morbidity in these patients. Prompt detection of infections, use of appropriate antibiotics for treatment and prophylactic measures such as vaccinations can help improve survival in these patients.

Subthreshold coexistence of strains: the impact of vaccination and mutation

We consider a model for a disease with two competing strains and vaccination. The vaccine provides complete protection against one of the strains (strain 2) but only partial protection against the other (strain 1). The partial protection leads to existence of subthreshold equilibria of strain 1. If the first strain mutates into the second, there are subthreshold coexistence equilibria when both vaccine-dependent reproduction numbers are below one. Thus, a vaccine that is specific toward the second strain and that, in absence of other strains, should be able to eliminate the second strain by reducing its reproduction number below one, cannot do so because it provides only partial protection to another strain that mutates into the second strain.

[Lactococcus lactis: an opportunistic bacterium?]

Lactic bacteria have been used for centuries to ferment food and thus, to better preserve them. Considered as inoffensive for man, its use has largely spread in food industry. Some species are even being considered for the treatment of human diseases. Indeed, the development of new cellular biology technologies opens opportunities for the use of these bacteria as biotherapeutic agents. These species would produce heterogeneous proteins such as enzymes (lipase, lactase, esterase), chemical mediators (hormones and interleukins), and molecules able to stimulate local immune responses. However, rare cases of human infection, sometimes severe, were reported recently. They generally occured in patients with comorbidities with consumption of unpasteurized dairy products reported for some. The scarcity of these cases and their favorable outcome should not hinder the industrial and medical use of these bacteria.

Validation of the Infectious Diseases Society of America's diabetic foot infection classification system

In this longitudinal study of 1666 persons with diabetes, there was an observed trend toward an increased risk for amputation (chi(2) test for trend, 108.0; P<.001), higher-level amputation (chi(2) test for trend, 113.3; P<.001), and lower extremity-related hospitalization (chi(2) test for trend, 118.6; P<.001) with increasing infection severity. The Infectious Diseases Society of America's foot infection classification system may be a useful tool for grading foot infections.

[Bile duct infections as a late complication after endoscopic sphincterotomy]

Nowadays endoscopic sphincterotomy (SE) is considered to be a "gold standard" in the treatment of residual choledocholithiasis and biliary pancreatitis. Nevertheless patients after invasive procedures concerning bile ducts with destruction of Oddi's sphincter often have increased succeptibility to chronic infections of bile ducts.

AIM

Assessment of the influence of SE on bacterial colonization, development of main bile duct chronic inflammation and recurrent choledocholithiasis.

MATERIAL AND METHODS

We included to the study 50 patients with main bile duct lithiasis, who underwent endoscopic cholangiopancreatography (ERCP). Among them there were 32 women in age from 45 to 87 (mean 69.7 +/- 12.3) and 18 men in age from 39 to 84 (mean 59.8 +/- 11.56). The studied group was divided into 3 subgroups: In I (control) group were included 10 patients diagnosed with ERCP techniques because of jaundice of unknown origin. Those patients did't have ERCP or operative revision of bile ducts before, but all of them underwent cholecystectomy in the past. Each II and III group consisted of 20 patients, who underwent SE before 12-24 and 25-36 months earlier respectively. Sterile uodenoscope was inserted to the region of major duodenal papilla, and then a sterile brush was used to collect material to cytological smear (brushing) from main bile duct. In all groups 2 ml of bile were taken by a catheter to a syringe. On the basis of radiograms from ERCP findings, the width of main bile duct was assessed. In all patients blood cell count, aspartate and alanine aminotransferases, gammaglutamyltranspeptidase, alkaline phosphatase, amylase, bilirubin, C-reactive protein and procalcitonine levels were measured.

RESULTS

In our study all 40 patients with previously performed endoscopic sphincterotomy (SE) had bacterial colonization in bile ducts, mostly with Gramm negative pathogens. The most virulent pathogens vere cultured from bile duct swabs from patients after two or more revisions of common bile duct, and after a longer time from sphincterotomy. Those patients had multibacterial bile duct infections (Escherichia coli + Pseudomonas aeruginosa; P. aeruginosa + Enterococcus faecalis; E. faecalis + Enterobacter cloacae + Candida albicans; P. aeruginosa + E. cloacae). E. coil and E. faecalis were most frequently cultured (20 and 16 cases respectively). It was observed that with length of time from endoscopic sphincterotomy, the width of main bile duct and also amount of cultured pathogens and their virulency grow. Elevated transaminases activity and serum procalcitonine levels were observed in studied groups. 9 patients after previous sphincterotomy had recurrent lithiasis.

CONCLUSIONS

Sphincterotomy contributes to colonization of main bile duct with pathogenic bacteria. With length of time from endoscopic sphincterotomy, and amount of performed endoscopic sphincterotomies the amount of cultured pathogens, their virulency and drug resistance grow. Chronic infection of bile ducts after endoscopic sphincterotomy causes higher risk of recurrent lithiasis.

Epidemiology of intensive care unit (ICU)-acquired infections in a 14-month prospective cohort study in a single mixed Scandinavian university hospital ICU

BACKGROUND

Our aim was to evaluate the epidemiology of intensive care unit (ICU)-acquired infections in a prospective cohort study.

METHODS

Patients with longer than a 48-h stay in an adult mixed medical-surgical ICU in a tertiary level teaching hospital were included. The incidence (per cent) and incidence density (per 1000 patient days) of ICU-acquired infections and the device-associated infection rates per 1000 device days were analysed prospectively in a 14-month study.

RESULTS

Eighty (23.9%) of 335 patients, whose ICU stay was longer than 48 h, acquired a total of 107 infections (1.3 per patient) during their ICU stay, with an infection rate of 48 per 1000 patient days. The most common infections were ventilator-associated pneumonia (VAP) [33.8% (18.8 per 1000 respiratory days)], other lower respiratory tract infections (LRTIs) (20%) and sinusitis (13.8%). The rate of central catheter-related (CRI) or primary bloodstream infections was 6.3% (2.2 per 1000 central venous catheter days), and the rate of urinary tract infections was 1.3% (0.5 per 1000 urinary catheter days). The first ICU infection was observed in 58.8% (47/80) of cases within 6 days after admission. The median time from admission to the diagnosis of an ICU-acquired infection was 4 days (25th-75th percentiles, 4.0-6.0) for VAP, 6.0 days (4.5-7.0) for LRTIs and 9.5 days (6.5-13.0) for CRIs.

CONCLUSIONS

The rates of urinary tract infections and bloodstream infections were lower than reported previously, differentiating our results from the classic pattern of ICU-acquired infections, with the exception of the predominance of VAP.

[Linezolid: antibacterial activity, clinical efficacy and resistance]

Linezolid is a synthetic antibiotic, the first available agent in a new class of antibiotic called the oxazolidinones, whose particular mechanism of action consists in inhibiting the initiation of protein synthesis. Its spectrum of in vitro and in vivo activity includes staphylococci, streptococci, enterococci, corynebacteria and some anaerobic bacteria (Peptostreptococcus, Clostridium, and Fusobacterium). The first therapeutic results were very encouraging, leading to the marketing of the product in France in 2002. Linezolid is indicated in the treatment of pneumonia and the complicated infections of the skin. Pharmacocinetics studies have shown that linezolid has an excellent bioavailability allowing a fast relay per os. However, failures of treatment under linezolid were reported and resistant strains of staphylococci and enterococci were obtained in vitro and in vivo after therapeutic use of this antibiotic. Changes in the domain V of 23S rRNA were found in the site of fixation, the most frequent was (G out of U) in position 2576 (numbering E. coli). In a context where resistance to traditional treatments in enterococci, pneumococci and S. aureus do not cease to increase, linezolid can be regarded as a therapeutic alternative to treat the infections with Gram-positive cocci.

[Soft tissue infection classification issues]

The authors give the summary on classification of soft tissues infections. Besides aetiopathogenesis and classification, separate clinical units are mentioned with the emphasis given on necrotizing processes and basic principles of their treatment. At the end own clinical material is presented with the results of microbiological analysis at the Departments of Surgery and Orthopedic surgery in University Hospital.

Sinusitis: viral, bacterial, or fungal and what is the role of Staph?

Recently, it has been recognized that inflammation is the major cause of chronic rhinosinusitis (CRS) rather than bacterial infection. Fungi have emerged as a possible pathogenic agent that drives CRS. One clear-cut group of fungal sinusitis can be divided into invasive and noninvasive. The condition that the allergist is most likely to see is allergic fungal sinusitis. Generally, it appears in atopic, immunocompetent, adolescents and young adults and is marked by the presence of nasal polyps and allergic mucin, which includes eosinophils, Charcot-Leyden crystals, and fungal hyphae. Computer tomographic imaging shows sinus opacification with hyperdense areas. Treatment has been successful with definitive nasosinus surgery and long-term oral prednisone. There is some evidence that fungi also may account for a large percentage of the remaining CRS patients. In this instance, the immune response to common airborne fungi appears to be IgG mediated rather than IgE mediated. Promising therapeutic results have been seen with intranasal antifungal agents but larger multicenter double-blinded placebo-controlled studies are needed. Another unanswered question includes the possible role of staphylococcus-derived enterotoxins in the pathogenesis of CRS.

[The chosen aspects of hospital infections]

The paper presents some basic data on hospital infections and their influence in evaluation of hospital functioning. The most common infections, microorganism which are the cause of them, the role of patient immunological state, ways of spreading infections and ways of preventing them have been presented.

[Epidemiology of nosocomial bacterial infections in a neonatal and pediatric Tunisian intensive care unit]

OBJECTIVE

The authors had for aim to describe the epidemiology of nosocomial bacterial infections in the neonatal and pediatric intensive care unit of the Tunis children's hospital.

DESIGN

A prospective surveillance study was made from January 2004 to December 2004. All patients remaining in the intensive care unit for more than 48 h were included. CDC criteria were applied for the diagnosis of nosocomial infections.

RESULTS

340 patients including 249 (73%) neonates were included. 22 patients presented with 22 nosocomial bacterial infections. The incidence and the density incidence rates of nosocomial bacterial infections were 6.5% and 7.8 per 1,000 patient-days, respectively. Two types of infection were found: bloodstream infections (68.2%) and pneumonias (22.7%). Bloodstream infections had an incidence and a density incidence rate of 4.4% and 15.3 per 1,000 catheter-days, respectively. Pneumonia had an incidence and a density incidence rate of 2% and 4.4 per 1,000 mechanical ventilation-days, respectively. The most frequently isolated pathogens were Gram-negative bacteria (68%) with Klebsiella pneumoniae isolates accounting for 22.7%. The most common isolate in bloodstream infections was K. Pneumoniae (26.7%), which was multiple drug-resistant in 85% of the cases, followed by Staphylococcus aureus (20%). Pseudomonas aeruginosa was the most common isolate in pneumonia (28.6%). Associated factors of nosocomial infection were invasive devices and colonization with multiple drug-resistant Gram-negative bacteria.

CONCLUSIONS

The major type of nosocomial bacterial infections in our unit was bloodstream infection and the majority of infections resulted from Gram-negative bacteria. Factors associated with nosocomial bacterial infections were identified in our unit.