Implementation of the WHO hand hygiene strategy in Faranah regional hospital, Guinea

BACKGROUND

Healthcare-associated infections are the most frequent adverse events in healthcare worldwide, with limited available evidence suggesting highest burden in resource-limited settings. Recent Ebola epidemics emphasize the disastrous impact that spread of infectious agents within healthcare facilities can have, accentuating the need for improvement of infection control practices. Hand hygiene (HH) measures are considered to be the most effective tool to prevent healthcare-associated infections. However, HH knowledge and compliance are low, especially in vulnerable settings such as Guinea. The aim of PASQUALE (Partnership to Improve Patient Safety and Quality of Care) was to assess knowledge and compliance with HH and improve HH by incorporating the WHO HH Strategy within the Faranah Regional Hospital (FRH), Guinea.

METHODS

In a participatory approach, a team of FRH staff and leadership was invited to identify priorities of the hospital prior to the start of PASQUALE. The local hygiene committee was empowered to increase its activities and take ownership of the HH improvement strategy. A baseline assessment of knowledge, perception and compliance was performed months before the intervention. The main intervention consisted of local alcohol-based-hand-rub (ABHR) production, with final product efficacy testing, in conjunction with a training adapted to the needs identified in the baseline assessment. A follow-up assessment was conducted directly after the training. Effectiveness of the intervention was assessed via uncontrolled before-and-after comparison.

RESULTS

Baseline knowledge score (13.0/25) showed a significant increase to 19.0/25 in follow-up. Baseline-Compliance was 23.7% and increased significantly to 71.5% in follow-up. Compliance rose significantly across all professional groups except for midwifes and in all indications for HH, with the largest in the indication "Before aseptic tasks". The increase in compliance was associated with the intervention and remained significant after adjusting for confounders. The local pharmacy successfully supplies the entire hospital. The local supply resulted in a ten-fold increase of monthly hospital disinfectant consumption.

CONCLUSION

The WHO HH strategy is an adaptable and effective method to improve HH knowledge and compliance in a resource-limited setting. Local production is a feasible method for providing self-sufficient supply of ABHR to regional hospitals like the FRH. Participatory approaches like hygiene committee ownership builds confidence of sustainability.

Increased incidence of Clostridium difficile PCR ribotype 027 in Hesse, Germany, 2011 to 2013

After the first outbreak of Clostridium difficile PCR ribotype (RT) 027 in Germany in 2007, no further outbreaks were reported until the recent re-emergence of RT 027 in Hesse, a federal state with 6 million inhabitants located in south-west Germany. We undertook a survey to determine the prevalence of RT 027 and other strains in a prospective study. From January 2011 to July 2013, we analysed 291 specimens from patients diagnosed with C. difficile infection (CDI) in 40 healthcare facilities in Hesse. The mean incidence of CDI in hospitals including at least 10 patients in the survey was 9.9 per 10,000 patient days (range 4.8-22.8) in November 2012. We obtained 214 toxigenic C. difficile isolates. RT 001 was the most prevalent (31.8%). RT 027, the second most common type (26.6%), was prevalent in all hospitals (n=14) from which at least seven isolates were available for typing, but its frequency varied considerably (range: 9.1–70%). The annual frequency of RT 027 increased from 21.4% in 2011 to 30.0% in 2013 (p=0.04). Our study indicates that infections with C. difficile RT 027 are now prevalent in Hesse. It underscores the need for surveillance programmes to analyse the molecular epidemiology of C. difficile.

Contamination of the cold water distribution system of health care facilities by Legionella pneumophila: Do we know the true dimension?

Binary file ES_Abstracts_Final_ECDC.txt matches

Contamination of the cold water distribution system of health care facilities by Legionella pneumophila: do we know the true dimension?

German water guidelines do not recommend routine assessment of cold water for Legionella in healthcare facilities, except if the water temperature at distal sites exceeds 25°C. This study evaluates Legionella contamination in cold and warm water supplies of healthcare facilities in Hesse, Germany, and analyses the relationship between cold water temperature and Legionella contamination. Samples were collected from four facilities, with cases of healthcare-associated Legionnaires' disease or notable contamination of their water supply. Fifty-nine samples were from central lines and 625 from distal sites, comprising 316 cold and 309 warm water samples. Legionella was isolated from central lines in two facilities and from distal sites in four facilities. 17% of all central and 32% of all distal samples were contaminated. At distal sites, cold water samples were more frequently contaminated with Legionella (40% vs 23%, p <0.001) and with higher concentrations of Legionella (≥1,000 colony-forming unit/100 ml) (16% vs 6%, p<0.001) than warm water samples. There was no clear correlation between the cold water temperature at sampling time and the contamination rate. 35% of cold water samples under 20 °C at collection were contaminated. Our data highlight the importance of assessing the cold water supply of healthcare facilities for Legionella in the context of an intensified analysis.

[Epidemiology of severe Clostridium difficile infections in Hesse, Germany in 2008-2009]

BACKGROUND AND OBJECTIVE

Clostridium difficile is a major cause of health care associated infections in industrialized countries. During the past decade, the incidence and clinical severity of C. difficile infections (CDI) have increased markedly. This increase has been associated with the emergence of a possibly highly virulent strain, the C. difficile PCR ribotype 027. We investigated the emergence of severe CDI and the associated PCR ribotypes in Hesse, Germany.

PATIENTS AND METHODS

We conducted a retrospective analysis of clinical information and ribotyping results of all cases of severe CDI that were reported to the Hesse State Health Office or sent to our microbiologic diagnostic laboratory for detection and molecular typing of C. difficile in severe cases of CDI from 01/2008 to 12/2009. The data of a of 88 patients and 50 isolates were analysed.

RESULTS

89% of patients were at least 65 years old; the mean age was 77 years. The clinical outcome was known in 85 patients. 27% had died within 30 days of the diagnosis of CDI. Ribotyping results were available in 39 and 11 patients from 2008 and 2009, respectively. The isolates were assigned to nine different ribotypes. RT 027 and RT 001 were the most frequent ribotypes with 31 and 10 isolates, respectively. All other ribotypes were isolated once or twice.

CONCLUSION

Our data indicate that C. difficile RT 027 and RT 001 are prevalent in Hesse and are often associated with severe or notifiable CDI. The high prevalence of RT 027 among the reported CDI cases does not indicate a generally high prevalence of the latter strain in Hesse, because detection of RT 027 was a case definition criterion, a fact that may cause a bias in the reported data. Further investigation would help to improve our understanding of the molecular epidemiology of severe CDI and to improve the prevention strategies.

Sulphonated cobalt phthalocyanine-MCM-41: an active photocatalyst for degradation of 2,4-dichlorophenol

The photocatalytic activity of sulphonated cobalt phthalocyanine immobilized onto MCM-41 was investigated for decomposition of 2,4-dichlorophenol (2,4-DCP) in aqueous solutions. Immobilization of anion sulpho-cobalt phthalocyanine to the walls of MCM-41 was performed by pre-anchorage of 3-(aminopropyl)-triethoxysilane (APTES) onto MCM-41 via post-synthesis method. X-ray diffraction, nitrogen physisorption, diffuse reflectance spectroscopy, energy-dispersive X-ray and FT-IR methods were used to characterize the product. Photocatalytic efficiency of the prepared catalyst for degradation of 2,4-DCP was tested under illumination of UV-A and visible light. The results obtained reveal that the photocatalyst is very active in degradation of 2,4-DCP. The photodegradation process is completed within 3h using a dose of 0.6g/L of the catalyst under UV irradiation. The reactions follow a pseudo-first-order kinetics and the observed rate constant values change with 2,4-DCP concentrations. The reproducibility of the catalyst was tested. The reaction intermediates were identified by gas chromatoghraphy-mass spectrometry (GC-MS) technique.

Clostridium difficile ribotypes 001, 017, and 027 are associated with lethal C. difficile infection in Hesse, Germany

From January 2008 to April 2009, 72 cases of severe Clostridium difficile infection were reported from 18 different districts in the state of Hesse, Germany. A total of 41 C. difficile isolates from 41 patients were subjected to PCR ribotyping. PCR ribotype (RT) 027 was the most prevalent strain accounting for 24 of 41 (59%) of typed isolates, followed by RT 001 (eight isolates, 20%), RT 017 and 042 (two isolates each), and RT 003, 066, 078, 081, and RKI-034 (one isolate each). Eighteen patients had died within 30 days after admission. C. difficile was reported as underlying cause of or contributing to death in 14 patients, indicating a case fatality rate of 19%. The patients with lethal outcome attributable to C. difficile were 59-89 years-old (median 78 years). Ribotyping results were available for seven isolates associated with lethal outcome, which were identified as RT 027 in three and as RT 001 and 017 in two cases each. Our data suggest that C. difficile RT 027 is prevalent in some hospitals in Hesse and that, in addition to the possibly more virulent RT 027, other toxigenic C. difficile strains like RT 001 and 017 are associated with lethal C. difficile infections in this region.

Enhanced adsorptive and photocatalytic achievements in removal of methylene blue by incorporating tungstophosphoric acid-TiO2 into MCM-41

The use of titania-dispersed materials in photocatalytic processes has been proposed as an alternative to the conventional bare TiO(2), in order to modify the surface area and activity of the catalyst. A homogeneously dispersed Keggin unit into TiO(2) was synthesized using tungstophosphoric acid (TPA) and titanium tetraisopropoxide. This compound was then loaded into MCM-41 by dispersing it in a suspension containing the mesoporous phase. Two other titanium-containing MCM-41 catalysts, Ti-MCM-41 and TiO(2)/MCM-41 were also prepared using isomorphous substitution synthesis method and impregnation method, respectively, for the sake of comparison. The prepared photocatalysts were characterized by X-ray diffraction (XRD), nitrogen physisorption (BET) and chemical analysis. The catalysts were used to study degradation of methylene blue (MB) in aqueous solution. XRD result shows a pure anatase crystalline phase for TPA-containing TiO(2) indicating that there is good molecular distribution of tungstophosphoric acid into TiO(2) structure. Supported TPA-TiO(2) into MCM-41 shows both TPA-TiO(2) and MCM-41 characteristic X-ray reflections in the high-angle and low-angle parts of the XRD patterns, respectively. The experimental results show that adsorption is a major constituent in the elimination of MB from the dye solutions by the TPA-containing materials. Exploitation of both adsorption and photocatalytic processes speeds up the removal of the dye using the TPA-TiO(2)-loaded MCM-41 photocatalyst. The elimination of MB is completed within 15 min for a 30 mg l(-1) MB solution containing a catalyst dose of 100mg/100ml. The efficiencies of the other photocatalysts such as commercial TiO(2), Ti-MCM-41, TiO(2)/MCM-41 and TPA-TiO(2) for adsorption and degradation of MB were also studied and compared with that of the prepared catalyst.

The potentiometric behavior of polymer-supported metallophthalocyanines used as anion-selective electrodes

Liquid polymer membrane electrodes based on nickel and manganese phthalocyanines were examined for use as anion-selective electrodes. The electrodes were prepared by incorporating the ionophores into plasticized poly(vinyl chloride) membranes, which were directly coated onto the surfaces of graphite electrodes. The resulting electrodes demonstrate near-Nernstian responses over a wide linear range of perchlorate anion (5 x 10(-7) to 1 x 10(-1) M). The electrodes have a fast response time, submicromolar detection limits (5 x 10(-7) M perchlorate), and could be used over a wide pH range of 3.5-10. The influences of lipophilic cationic and anionic additives on the response properties of the electrodes were investigated. The proposed sensors revealed high selectivity for perchlorate over a number of common inorganic and organic anions. The highest selectivity was observed for the electrode based on manganese phthalocyanine in the presence of the lipophilic anionic additive sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate. Application of the electrodes to determine perchlorate in tap water and human urine is also reported.

Prevalence of erythromycin and clindamycin resistance among Streptococcus agalactiae isolates in Germany

The antimicrobial susceptibilities of 338 clinical Streptococcus agalactiae isolates from two geographical regions in Germany were determined by agar dilution. All isolates were susceptible to penicillin, cefotaxime and vancomycin. The overall frequencies of erythromycin and clindamycin resistance were 11% and 4.7%, respectively. Determination of resistance phenotypes among the 37 erythromycin-resistant isolates revealed constitutive and inducible MLS(B) resistance in 40.6% and 37.8% of isolates, respectively, and susceptibility to clindamycin in 21.6% of isolates. Only 14.3% of isolates with inducible MLS(B) resistance were identified as clindamycin-resistant by determination of clindamycin MICs. Pulsed-field gel electrophoresis suggested a clonal distribution pattern among the erythromycin-resistant isolates.

Direct determination of triamterene by potentiometry using a coated wire selective electrode

A coated wire triamterene-selective electrode based on the incorporation of a triamterene-tetraphenylborate ion-pair in a poly(vinylchloride) coating membrane was constructed. The influence of membrane composition, temperature, pH of the test solution, and foreign ions on the electrode performance were investigated. The electrode showed a Nernstian response over a triamterene concentration range from 1.0 x 10(-6) to 3.5 x 10(-2) M, at 25 degrees C, and was found to be very selective, precise, and usable within the pH range 4.5-7.5. The standard electrode potentials, E degrees, were determined at 15, 20, 25, 30, 35, 40 and 45 degrees C and used to calculate the isothermal temperature coefficient (dE degrees /dt) of the electrode. Temperatures higher than 45 degrees C seriously affected the electrode performance. The electrode was successfully applied to the potentiometric determination of triamterene hydrochloride both in pure solutions and in pharmaceutical preparations.

Characterization of the natural population of Bartonella henselae by multilocus sequence typing

Investigations of the population genetics of Bartonella henselae have demonstrated a high level of diversity among strains, and the delineation of isolates into one of two subtypes, type I (Houston) and type II (Marseille), represented by specific 16S ribosomal DNA (rDNA) sequences, has long been considered the most significant genotypic division within the species. This belief is challenged by recent work suggesting a role for horizontal gene exchange in generating intraspecies diversity. We attempted to resolve this issue and extend exploration of the population structure of B. henselae by using multilocus sequence typing (MLST) to examine the distribution of polymorphisms within nine different genes in a sample of 37 human and feline isolates. MLST distinguished seven sequence types (STs) that resolved into three distinct lineages, suggesting a clonal population structure for the species, and support for these divisions was obtained by macrorestriction analysis using pulsed-field gel electrophoresis. The distribution of STs among isolates recovered from human infections was not random, and such isolates were significantly more often associated with one particular ST, lending further support to the suggestion that specific genotypes contribute disproportionately to the disease burden in humans. All but one isolate lay on lineages that bore the representative strain of either the Houston or Marseille subtype. However, the distribution of the two 16S rDNA alleles among the isolates was not entirely congruent with their lineage allocations, indicating that this is not a sensitive marker of the clonal divisions within the species. The inheritances of several of the genes studied could not be reconciled with one another, providing further evidence of horizontal gene transfer among B. henselae strains and suggesting that recombination has a role in shaping the genetic character of bartonellae.

Bartonella henselae-specific cell-mediated immune responses display a predominantly Th1 phenotype in experimentally infected C57BL/6 mice

Immune responses of the immunocompetent host to Bartonella henselae infection were investigated in the murine infection model using C57BL/6 mice. Following intraperitoneal infection with human-derived B. henselae strain Berlin-1, viable bacteria could be recovered from livers and spleens during the first week postinfection, while Bartonella DNA remained detectable by PCR in the liver for up to 12 weeks after infection. Granulomatous lesions developed in livers of infected mice, reached maximal density at 12 weeks after infection, and persisted for up to 20 weeks, indicating that B. henselae induced a chronic granulomatous hepatitis in the immunocompetent murine host. T-cell-mediated immune responses were analyzed in vitro by means of spleen cell proliferation and cytokine release assays as well as analysis of immunoglobulin G (IgG) isotypes. Spleen cells from infected mice proliferated specifically upon stimulation with heat-killed Bartonella antigen. Proliferative responses were mainly mediated by CD4+ T cells, increased during the course of infection, peaked at 8 weeks postinfection, and decreased thereafter. Gamma interferon, but not interleukin-4, was produced in vitro by spleen cells from infected animals upon stimulation with Bartonella antigens. Bartonella-specific IgG was detectable in serum of infected mice by 2 weeks, and the antibody concentration peaked at 12 weeks postinfection. IgG2b was the prominent isotype among the Bartonella-specific serum IgG antibodies. These data indicate that B. henselae induces cell-mediated immune responses with a Th1 phenotype in immunocompetent C57BL/6 mice.

Bartonella henselae induces NF-kappaB-dependent upregulation of adhesion molecules in cultured human endothelial cells: possible role of outer membrane proteins as pathogenic factors

The endothelium is a specific target for Bartonella henselae, and endothelial cell infection represents an important step in the pathogenesis of cat scratch disease and bacillary angiomatosis. Mechanisms of Bartonella-endothelial cell interaction as well as signaling pathways involved in target cell activation were analyzed. B. henselae strain Berlin-1, isolated from bacillary angiomatosis lesions of a human immunodeficiency virus-infected patient, potently stimulated human umbilical cord vein endothelial cells (HUVEC), as determined by NF-kappaB activation and enhanced adhesion molecule expression. These effects were accompanied by increased PMN rolling on and adhesion to infected endothelial cell monolayers, as measured in a parallel-plate flow chamber assay. Monoclonal antibodies against E-selectin significantly reduced PMN rolling and adhesion. In our hands, B. henselae Berlin-1 was substantially more active than the typing strain B. henselae ATCC 49882. E-selectin and ICAM-1 upregulation occurred for up to 9 days, as verified by Northern blotting and cell surface enzyme-linked immunosorbent assay. Induction of adhesion molecules was mediated via NF-kappaB activation and could be blocked by a specific NF-kappaB inhibitor. Additional studies indicated that B. henselae-induced effects did not require living bacteria or Bartonella lipopolysaccharides. Exposure of HUVEC to purified B. henselae outer membrane proteins (OMPs), however, reproduced all aspects of endothelial cell activation. In conclusion, B. henselae, the causative agent of cat scratch disease and bacillary angiomatosis, infects and activates endothelial cells. B. henselae OMPs are sufficient to induce NF-kappaB activation and adhesion molecule expression followed by enhanced rolling and adhesion of leukocytes. These observations identify important new properties of B. henselae, demonstrating its capacity to initiate a cascade of events culminating in a proinflammatory phenotype of infected endothelial cells.

Rapid increase of mucosal CD4 T cells followed by clearance of intestinal cryptosporidiosis in an AIDS patient receiving highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) suppresses the replication of human immunodeficiency virus (HIV) and leads to an increase in circulating CD4 T lymphocytes, but its effects on other immune compartments such as the intestinal mucosa are not well understood. We describe a severely immunodeficient HIV-infected patient with intractable watery diarrhea and weight loss caused by infection with Cryptosporidium parvum in whom we studied virologic and immunologic changes in both peripheral blood and the intestinal mucosa after initiating HAART. Mucosal biopsies were performed by rectoscopy before and at several time points after HAART was begun. Nucleic acids were extracted from rectal biopsy specimens and blood samples, and HIV RNA was measured by reverse-transcription polymerase chain reaction. Lymphocytes were isolated from rectal biopsy specimens after mechanical disaggregation, and circulating and mucosal CD4 T cells were determined by flow cytometry. HAART led to clinical recovery and eradication of cryptosporidiosis. In both blood and mucosa, HIV RNA decreased below the limit of detection and CD4 T cells increased. Mucosal CD4 T cells increased much faster and to much higher levels than circulating CD4 T cells. Our findings show a rapid repopulation of the intestinal mucosa with CD4 T cells after initiation of HAART that can effectively restore mucosal immunity, leading to eradication of opportunistic pathogens.

Genetic variability and prevalence of Bartonella henselae in cats in Berlin, Germany, and analysis of its genetic relatedness to a strain from Berlin that is pathogenic for humans

Nineteen Bartonella henselae strains and one Bartonella clarridgeiae strain were isolated from blood samples of 97 pet cats and 96 stray cats from Berlin, Germany, indicating prevalence rates of 1 and 18.7%, respectively, for B. henselae and 0 and 1%, respectively, for B. clarridgeiae. Eighteen of 19 B. henselae isolates corresponded to 16S rRNA type II. Pulsed-field gel electrophoresis (PFGE) analysis revealed seven different PFGE types among the feline B. henselae strains. Interestingly, all feline isolates displayed low genetic relatedness to B. henselae strain Berlin-1, which is pathogenic for humans.

Antimicrobial resistance in Streptococcus pyogenes isolates in Berlin

A total of 212 clinical Streptococcus pyogenes isolates were tested for susceptibility to various antibiotics by agar dilution. The overall frequency of erythromycin resistance was 12.7%, being higher in isolates from children (18.9%) than in those from adult patients (10.7%). Similar results were found for clarithromycin, while 2.8% of the isolates were resistant to ciprofloxacin. All strains were susceptible to penicillin and cefotaxime. Of the erythromycin-resistant isolates subjected to the double-disc diffusion test for erythromycin and clindamycin, 35% expressed constitutive and 55% inducible resistance to clindamycin. Ten per cent were susceptible to clindamycin (M-phenotype). Thus, a high rate of macrolide resistance in S. pyogenes has emerged in Berlin.

[Antibiotic susceptibility of Neisseria gonorrhoeae isolates in Berlin]

BACKGROUND AND OBJECTIVE

Because of the increasing resistance of Neisseria gonorrhoeae, we studied the actual resistance of isolates in Berlin.

PATIENTS/METHODS

85 Neisseria gonorrhoeae isolates were collected between 1995 and 1997. Susceptibility testing was performed for penicillin G, tetracycline, spectinomycin, ceftriaxone, ciprofloxacin and azithromycin by agar dilution.

RESULTS

18.8% isolates were resistant or intermediately resistant to penicillin G (including 6 PPNG). 12.9% isolates were resistant, 43.5% intermediately resistant to tetracycline. One strain was resistant against ciprofloxacin, 4 isolates showed increased MIC values (0.06-0.5 mg/l), whereas 78 isolates were fully susceptible (< 0.007 mg/l). All isolates were susceptible to spectinomycin, ceftriaxone, and azithromycin.

CONCLUSIONS

Penicillin G and tetracycline should be given only in cases of proven sensibility. Resistance against ciprofloxacin may occur, especially in isolates acquired in south-east Asia. Ceftriaxone, spectinomycin and azithromycin were active against all isolates. The actual resistance situation should be monitored.

Murine model of Bartonella henselae infection in the immunocompetent host

Bartonella henselae is an emerging pathogen causing cat scratch disease, bacillary angiomatosis, and peliosis hepatis. Progress in understanding the pathogenesis of and the immune response to these infections has been limited by the lack of an animal model. Following intraperitoneal infection of C57BL/6 mice with B. henselae, organs were cleared of cultivatable bacteria within 6 days. In contrast, B. henselae DNA could be detected in liver tissue for at least 3 months. Liver tissue showed granulomatous inflammation reaching its highest degree of intensity during the fourth week of infection and resolving within 12 weeks postinfection. This mouse model is applicable to the study of the pathogenesis of B. henselae and the immune response to this pathogen in the immunocompetent host.

Characterization of Bartonella henselae isolated from bacillary angiomatosis lesions in a human immunodeficiency virus-infected patient in Germany

Infections with Bartonella (Rochalimaea) henselae can result in a variety of clinical entities, including bacillary angiomatosis in immunocompromised hosts. The fastidious nature of this bacterium has so far prevented the culture of many clinical isolates. We report the recovery of the first European B. henselae isolate associated with bacillary angiomatosis. The isolate was cultured in a frozen skin biopsy specimen from a human immunodeficiency virus (HIV)-infected patient and was characterized by means of biochemical, bacteriologic, immunologic, and molecular biological methods including pulsed-field gel electrophoresis. This strain was compared with two B. henselae strains isolated in the United States to determine the relationship between the isolates. We found that it was phenotypically and genotypically indiscernible from B. henselae Houston-1, a blood culture isolate from an HIV-infected patient in Houston. These data suggest that one B. henselae clone is associated with human infections in Europe and the United States.

A new acid-fast trichrome stain for simultaneous detection of Cryptosporidium parvum and microsporidial species in stool specimens

The detection in stool specimens of Cryptosporidium parvum and microsporidia, the most frequent parasitic pathogens causing diarrhea in AIDS patients, until now has depended on two different staining methods. However, since double infections occur and minimization of laboratory costs is mandatory, development of a method for simultaneous detection of these parasites appeared desirable. We report on a new, inexpensive, and easy-to-perform staining procedure to demonstrate both acid-fast oocysts of C. parvum and other coccidia, as well as microsporidial spores. This acid-fast trichrome stain yields results comparable to those obtained by the Kinyoun and modified trichrome methods and considerably reduces the time necessary for microscopic examination.

T-cell activation and proliferation in a case of recurrent menstrual toxic shock syndrome

A case of menses-related toxic shock syndrome with a relapse within 9 days is presented. Cervical smear of the patient yielded growth of a Staphylococcus aureus strain which produced toxic shock syndrome toxin-1 (TSST-1). Serum antibody against TSST-1 were absent in the first sample which was obtained in the acute phase and did not increase significantly within 5 weeks. We studied the proliferative response of the patient's T cells during and after the acute phase of disease to evaluate whether they have been rendered unresponsive to TSST-1. We could not detect any reduction in the T cell proliferation at any time. Peripheral T cells of the patient were analysed flow-cytometrically at two different times to determine the expression of the T cell activity markers CD25 and HLA-DR. The expression of HLA-DR was increased during the acute phase and had declined significantly at the time of the second analysis; the CD25 expression remained constant.

Streptococcal toxic shock syndrome associated with marked gamma delta T cell expansion: case report

Streptococcal toxic shock syndrome (strepTSS) has been associated with various streptococcal soft-tissue infections including cellulitis, necrotizing fasciitis, and peritonitis in adults. We describe a 40-year-old patient with pharyngitis and strepTSS. Throat swab cultures yielded a strain of Streptococcus pyogenes that produced large amounts of erythrogenic toxin A. Fluorescence-activated cell sorter analysis of the patient's peripheral blood lymphocytes revealed generally enhanced expression of the T cell activity markers CD25 and human leukocyte antigen-DR and a marked increase in the number of gamma delta T cells, largely of the V delta 1-bearing subpopulation. Two more analyses, which were performed 2 weeks and 9 months later, respectively, documented the course of normalization after the acute episode of strepTSS. The T cells of this patient were stimulated in vitro with supernatants of his streptococcal isolate, and they proliferated in a dose-dependent manner. These proliferating T cells were mainly alpha beta T cells.

Staphylococcus aureus alpha-toxin attack on human platelets promotes assembly of the prothrombinase complex

alpha-Toxin, the major cytolysin of Staphylococcus aureus, promotes blood coagulation by its attack on human platelets (Bhakdi S., Muhly, M., Mannhardt, U., Hugo, F., Klapettek, K., Mueller-Eckhardt, C., and Roka, L. (1988) J. Exp. Med. 168, 527-542). In the present study we demonstrate that toxin attack on gel-filtered human platelets initiates the assembly of prothrombinase complexes at rates up to 10-fold of controls. Treatment of platelets with 0.1 microgram/ml alpha-toxin resulted in generation of 1.4 units of thrombin/10(8) platelets. A similar rate of thrombin generation was noted when platelets were subjected to three cycles of freezing and thawing. However, the alpha-toxin-induced prothrombinase activity was not due to platelet lysis, since less than 1% of total cellular lactate dehydrogenase was released by this alpha-toxin concentration. Two distinct and dissociable processes contributed to enhanced prothrombinase assembly. First, alpha-toxin promoted the exocytotic release of factor V from alpha-granules, which was accompanied by co-secretion of platelet factor 4. This process was calcium-dependent. Second, toxin-treated platelets exhibited an enhanced capacity to bind external factor V(a), a phenomenon that was not linked to Ca2(+)-dependent factor V secretion. Assembly of prothrombinase complexes via these two mechanisms together accounts for the procoagulant action of S. aureus alpha-toxin.

Identification of [1-14C]pantothenic-acid-mediated modified mitochondrial proteins

The in vivo administration of [1-14C]pantothenic acid, which is the precursor of coenzyme A, resulted in the radioactive labelling of several mitochondrial proteins in rat liver. The incorporated radioactivity could be released by glutathione or 2-mercaptoethanol. Two mitochondrial matrix proteins acetyl-CoA acetyltransferase (liver and heart), an enzyme involved in the biosynthesis or degradation of ketone bodies, and 3-oxoacyl-CoA thiolase (liver), a protein participating in fatty acid oxidation were identified as modified proteins. The radioactivity was localized exclusively in forms A1 and A2 indicating that these forms represent the modified states of the acetyl-CoA acetyltransferase protein. Kinetics of incorporation of radioactivity revealed an accumulation of the modified forms. The ratio of specific radioactivities of A2 compared to A1 was 2.41 +/- 0.15 (n = 10). After in vivo labelling with [14C]leucine, the specific radioactivity of acetyl-CoA acetyltransferase depended on the state of the enzyme protein. The unmodified enzyme exhibited a lower specific radioactivity than its modified forms suggesting different turnover rates of these proteins.

Identification with monoclonal antibodies of hemolysin produced by clinical isolates of Escherichia coli

Murine monoclonal antibodies were generated against the 107,000-dalton hemolysin encoded by the hemolytic determinant from Escherichia coli LE 2001, and colony blotting was used to assay for production of the hemolysin by 35 hemolytic strains of E. coli and other hemolytic members of the family Enterobacteriaceae of clinical origin. All hemolytic E. coli strains gave positive reactions with two monoclonal antibodies. In contrast, none of the hemolytic, non-E. coli isolates yielded positive colony blots. In addition, Western blotting showed that the hemolysins produced by all clinical E. coli isolates had a similar molecular weight of about 107,000. Discrete antigenic variation may occur in the molecule, since a third monoclonal antibody did not react with the hemolysin from a number of wild-type E. coli strains. Western blot analysis was used to assess the presence of immunoglobulin G (IgG), IgA, and IgM antibodies to E. coli hemolysin in human sera. All 20 of the tested sera from healthy adults contained antibodies to the toxin, with various constellations among the antibody classes. In contrast, sera from five of eight infants aged 8 to 36 months contained no antihemolysin antibodies. We conclude that the 107,000-dalton hemolysin of E. coli is a widespread immunogen that is produced by most or all hemolytic E. coli strains in the human host.

Use of a monoclonal antibody to determine the mode of transmembrane pore formation by streptolysin O

Murine monoclonal antibodies were generated against streptolysin O. One out of 10 tested immunoglobulin clones exhibited strong neutralizing activity; in solution, the presence of approximately two to four antibody molecules per toxin monomer effected 50% neutralization of hemolytic toxin activity. An enzyme-linked immunosorbent assay performed with target cell membranes that were treated with streptolysin O in the presence and absence of neutralizing antibodies showed that the antibodies did not block primary binding of the toxin to the cells. When membranes were solubilized in deoxycholate detergent and centrifuged in sucrose density gradients, those lysed with streptolysin O contained detergent-resistant, high-molecular-weight oligomers identical to the pore lesions, whereas those given toxin and neutralizing antibody contained the toxin exclusively in low-molecular-weight, nonoligomerized form. The process of pore formation by streptolysin O must thus involve two distinct steps, i.e., the primary binding of toxin molecules to the membrane followed by oligomerization of bound toxin monomers by lateral aggregation in the lipid bilayer to form the transmembrane pores.