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BACKGROUND: The long-term course of immunity among individuals with a history of COVID-19, in particular among those who received a booster vaccination, has not been well defined so far. METHODS: SARS-CoV-2-specific antibody levels were measured by ELISA over 1 year among 136 health care workers infected during the first COVID-19 wave and in a subgroup after booster vaccination approximately 1 year later. Furthermore, spike-protein-reactive memory T cells were quantified approximately 7 months after the infection and after booster vaccination. Thirty healthy individuals without history of COVID-19 who were routinely vaccinated served as controls. RESULTS: Levels of SARS-CoV-2-specific IgM- and IgA-antibodies showed a rapid decay over time, whereas IgG-antibody levels decreased more slowly. Among individuals with history of COVID-19, booster vaccination induced very high IgG- and to a lesser degree IgA-antibodies. Antibody levels were significantly higher after booster vaccination than after recovery from COVID-19. After vaccination with a two-dose schedule, healthy control subjects developed similar antibody levels as compared to individuals with history of COVID-19 and booster vaccination. SARS-CoV-2-specific memory T cell counts did not correlate with antibody levels. None of the study participants suffered from a reinfection. CONCLUSIONS: Booster vaccination induces high antibody levels in individuals with a history of COVID-19 that exceeds by far levels observed after recovery. SARS-CoV-2-specific antibody levels of similar magnitude were achieved in healthy, COVID-19-naïve individuals after routine two-dose vaccination.
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COVID-19 , Anticorpos Antivirais , COVID-19/prevenção & controle , Seguimentos , Humanos , SARS-CoV-2 , VacinaçãoRESUMO
BACKGROUND: The immune response to COVID-19-vaccination differs between naïve vaccinees and those who were previously infected with SARS-CoV-2. Longitudinal quantitative and qualitative serological differences in these two distinct immunological subgroups in response to vaccination are currently not well studied. METHODS: We investigate a cohort of SARS-CoV-2-naïve and COVID-19-convalescent individuals immediately after vaccination and 6 months later. We use different enzyme-linked immunosorbent assay (ELISA) variants and a surrogate virus neutralization test (sVNT) to measure IgG serum titers, IgA serum reactivity, IgG serum avidity and neutralization capacity by ACE2 receptor competition. RESULTS: Anti-receptor-binding domain (RBD) antibody titers decline over time in dually vaccinated COVID-19 naïves whereas titers in single dose vaccinated COVID-19 convalescents are higher and more durable. Similarly, antibody avidity is considerably higher among boosted COVID-19 convalescent subjects as compared to dually vaccinated COVID-19-naïve subjects. Furthermore, sera from boosted convalescents inhibited the binding of spike-protein to ACE2 more efficiently than sera from dually vaccinated COVID-19-naïve subjects. CONCLUSIONS: Long-term humoral immunity differs substantially between dually vaccinated SARS-CoV-2-naïve and COVID-19-convalescent individuals. Booster vaccination after COVID-19 induces a more durable humoral immune response in terms of magnitude and quality as compared to two-dose vaccination in a SARS-CoV-2-naïve background.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Imunidade Humoral , Enzima de Conversão de Angiotensina 2 , Imunoglobulina G , Anticorpos Antivirais , Anticorpos NeutralizantesRESUMO
OBJECTIVE: To follow serological immune responses of front-line healthcare workers after PCR-confirmed COVID-19 for a mean of 30 weeks, describe the time-course of SARS-CoV-2 spike protein-specific IgG, IgA and IgM levels and to identify associations of the immune response with symptoms, demographic parameters and severity of disease. METHODS: Anti-SARS-CoV-2 S protein-specific IgG, IgA and IgM antibodies were measured at three time points during the 30-week follow-up. COVID-19-specific symptoms were assessed with standardized questionnaires. RESULTS: 95% of the participants mounted an IgG response with only modest decline after week 12. IgG-type antibodies were still detectable in almost 90% of the subjects at 30 weeks. IgA and IgM responses were less robust and antibody titers decreased more rapidly. At 30 weeks, only 25% still had detectable IgA-type and none had IgM-type antibodies. Higher age and higher disease severity were independently associated with higher IgG antibody levels, albeit with wide variations. CONCLUSION: Serological immune responses after COVID-19 show considerable inter-individual variability, but show an association with increasing age and higher severity of disease. IgG-type anti-SARS-CoV-2 antibodies remain positive in 90% of the individuals 30 weeks after onset of symptoms.
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Anticorpos Antivirais/sangue , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Algoritmos , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Inquéritos e Questionários , Fatores de Tempo , Adulto JovemRESUMO
OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic challenges national health systems and the global economy. Monitoring of infection rates and seroprevalence can guide public health measures to combat the pandemic. This depends on reliable tests on active and former infections. Here, we set out to develop and validate a specific and sensitive enzyme linked immunosorbent assay (ELISA) for detection of anti-SARS-CoV-2 antibody levels. METHODS: In our ELISA, we used SARS-CoV-2 receptor-binding domain (RBD) and a stabilized version of the spike (S) ectodomain as antigens. We assessed sera from patients infected with seasonal coronaviruses, SARS-CoV-2 and controls. We determined and monitored IgM-, IgA- and IgG-antibody responses towards these antigens. In addition, for a panel of 22 sera, virus neutralization and ELISA parameters were measured and correlated. RESULTS: The RBD-based ELISA detected SARS-CoV-2-directed antibodies, did not cross-react with seasonal coronavirus antibodies and correlated with virus neutralization (R2 = 0.89). Seroconversion started at 5 days after symptom onset and led to robust antibody levels at 10 days after symptom onset. We demonstrate high specificity (99.3%; N = 1000) and sensitivity (92% for IgA, 96% for IgG and 98% for IgM; > 10 days after PCR-proven infection; N = 53) in serum. CONCLUSIONS: With the described RBD-based ELISA protocol, we provide a reliable test for seroepidemiological surveys. Due to high specificity and strong correlation with virus neutralization, the RBD ELISA holds great potential to become a preferred tool to assess thresholds of protective immunity after infection and vaccination.
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Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , COVID-19/diagnóstico , Ensaio de Imunoadsorção Enzimática/normas , Testes de Neutralização/normas , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Neutralizantes/sangue , Antígenos Virais/química , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Estudos Transversais , Humanos , Soros Imunes/química , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Domínios Proteicos , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/químicaAssuntos
Betacoronavirus/patogenicidade , Controle de Doenças Transmissíveis/organização & administração , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Pneumonia Viral/epidemiologia , COVID-19 , China/epidemiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/prevenção & controle , Previsões , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/mortalidade , Pneumonia Viral/prevenção & controle , SARS-CoV-2RESUMO
SARS-CoV-2 Omicron is the first pandemic variant of concern exhibiting an abrupt accumulation of mutations particularly in the receptor-binding domain that is a critical target of vaccination induced and therapeutic antibodies. Omicron's mutations did only marginally affect the binding of ACE2, and the two antibodies Sotrovimab and CR3022 but strongly impaired the binding of Casirivimab and Imdevimab. Moreover, as compared with Wuhan, there is reduced serum reactivity and a pronounced loss of competitive surrogate virus neutralization (sVN) against Omicron in naïve vaccinees and in COVID-19 convalescents after infection and subsequent vaccination. Finally, although the booster vaccination response conferred higher titers and better sVN, the effect was nonetheless significantly lower compared with responses against Wuhan. Overall, our data suggest that the antigenicity of Omicrons receptor binding motive has largely changed but antibodies such as Sotrovimab targeting other conserved sites maintain binding and therefore hold potential in prophylaxis and treatment of Omicron-induced COVID-19.
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Serological testing is crucial in detection of previous infection and in monitoring convalescent and vaccine-induced immunity. During the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) pandemic, numerous assay platforms have been developed and marketed for clinical use. Several studies recently compared clinical performance of a limited number of serological tests, but broad comparative evaluation is currently missing. Within this study, a panel of 161 sera from SARS-CoV-2 infected, seasonal CoV-infected and SARS-CoV-2 naïve subjects was enrolled to evaluate 16 ELISA/ECLIA-based and 16 LFA-based tests. Specificities of all ELISA/ECLIA-based assays were acceptable and generally in agreement with the providers' specifications, but sensitivities were lower as specified. Results of the LFAs were less accurate as compared to the ELISAs, albeit with some exceptions. We found a sporadic unequal immune response for different antigens and thus recommend the use of a nucleocapsid protein (N)- and spike protein (S)-based test combination when maximal sensitivity is necessary. Finally, the quality of the immune response in terms of neutralization should be tested using S-based IgG tests.
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BACKGROUND: Fecal microbiota transfer (FMT) has become a standard of care in the prevention of multiple recurrent Clostridioides difficile (rCDI) infection. AIM: While primary cure rates range from 70-80% following a single treatment using monodirectional approaches, cure rates of combination treatment remain largely unknown. METHODS: In a retrospective case-control study, outcomes following simultaneous bidirectional FMT (bFMT) with combined endoscopic application into the upper and lower gastrointestinal tract, compared to standard routes of application (endoscopy via upper or lower gastrointestinal tract and oral capsules; abbreviated UGIT, LGIT and CAP) on day 30 and 90 after FMT were assessed. Statistical matching partners were identified using number of recurrences (<3; ≥3), age and gender. RESULTS: Primary cure rates at D30 and D90 for bFMT were 100% (p=.001). The matched control groups showed cure rates of 81.3% for LGIT (p=.010), 62.5% for UGIT (p=.000) and 78.1% for CAP (p=.005) on D30 and 81.3% for LGIT (p=.010), 59.4% for UGIT (p=.000) and 71.9% for CAP (p=.001) on D90. CONCLUSION: In our analysis, bFMT on the same day significantly increased primary cure rate at D30 and D90. These data require prospective confirmation but suggest that route of application may play a significant role in optimizing patient outcomes. ClinicalTrials.gov no: NCT02681068.
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Infecções por Clostridium/terapia , Transplante de Microbiota Fecal/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Sistema de Registros , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The family of Toll-like receptors (TLRs) plays a pivotal role in host defense against pathogens. However, overstimulation of these receptors may lead to uncontrolled general inflammation and eventually to systemic organ dysfunction or failure. With the intent to control overwhelming inflammation during gram-negative bacterial sepsis, we constructed soluble fusion proteins of the lipopolysaccharide (LPS)-receptor complex to modulate TLR signaling in multiple ways. The extracellular domain of mouse TLR4 and mouse myeloid differentiation factor 2 (MD-2) fusions (LPS-Trap) were linked to human immunoglobulin G Fc domains (LPS-Trap-Fc). In addition to the ability to bind LPS or gram-negative bacteria and to inhibit interleukin-6 secretion of monocytic cells after LPS treatment, LPS-Trap-Fc was able to opsonize fluorescent Escherichia coli particles. This led to enhancement of phagocytosis by monocytic cells which was strictly dependent on the presence of the Fc region. Moreover, only LPS-Trap-Fc- and not LPS-Trap-coated bacteria were sensitized to complement killing. Therefore, LPS-Trap-Fc not only neutralizes LPS but also, after binding to bacteria, enhances phagocytosis and complement-mediated killing and could thus act as a multifunctional agent to fight gram-negative bacteria in vivo.
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Escherichia coli/imunologia , Fatores Imunológicos/uso terapêutico , Animais , Linhagem Celular , Proteínas do Sistema Complemento/imunologia , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Fatores Imunológicos/farmacologia , Antígeno 96 de Linfócito/genética , Camundongos , Viabilidade Microbiana , Monócitos/imunologia , Proteínas Opsonizantes , Fagocitose , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Receptor 4 Toll-Like/genéticaRESUMO
Introduction: Fecal microbiota transfer (FMT) is highly effective in the treatment and prevention of recurrent Clostridioides difficile infection (rCDI) with cure rates of about 80% after a single treatment. Nevertheless, the reasons for failure in the remaining 20% remain largely elusive. The aim of the present study was to investigate different potential clinical predictors of response to FMT in Germany. Methods: Information was extracted from the MicroTrans Registry (NCT02681068), a retrospective observational multicenter study, collecting data from patients undergoing FMT for recurrent or refractory CDI in Germany. We performed binary logistic regression with the following covariates: age, gender, ribotype 027, Eastern Co-operative Oncology Group score, immunosuppression, preparation for FMT by use of proton pump inhibitor, antimotility agents and bowel lavage, previous recurrences, severity of CDI, antibiotic induction treatment, fresh or frozen FMT preparation, and route of application. Results: Treatment response was achieved in 191/240 evaluable cases (79.6%) at day 30 (D30) post FMT and 78.1% at day 90 (D90) post FMT. Assessment of clinical predictors for FMT failure by forward and confirmatory backward-stepwise regression analysis yielded higher age as an independent predictor of FMT failure (p = 0.001; OR 1.060; 95%CI 1.025-1.097). Conclusion: FMT in Germany is associated with high cure rates at D30 and D90. No specific pre-treatment, preparation or application strategy had an impact on FMT success. Only higher age was identified as an independent risk factor for treatment failure. Based on these and external findings, future studies should focus on the assessment of microbiota and microbiota-associated metabolites as factors determining FMT success.
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Clostridioides difficile , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Transplante de Microbiota Fecal/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Prevenção Secundária , Falha de TratamentoRESUMO
OBJECTIVE: The clinical effect of beta-lactam antibiotics depends on the time of drug concentration above the minimal inhibitory concentration (MIC) for a susceptible bacterium. Continuous infusion (CI) of beta-lactams such as meropenem may therefore be a more rational approach than intermittent bolus injections (IB). The aim of this study was to test whether CI of meropenem achieves effective drug concentrations comparable to IB in patients treated by continuous renal replacement therapy (CRRT). DESIGN: Prospective, randomised cross-over study. SETTING: Twelve-bed medical intensive care unit (ICU). PATIENTS AND INTERVENTIONS: Six ICU patients were randomised to receive either meropenem 1 g IB every 12 h or a 0.5 g i.v. loading dose followed by 2 g i.v. CI over 24 h. After 2 days, regimens were crossed over. Meropenem pharmacokinetics were determined on days 2 and 4. MEASUREMENTS AND RESULTS: Peak serum concentration [median (25% and 75% quartiles)] after short infusion of 1 g meropenem were 62.8 (51.4; 85.0) mg/l, trough levels at 12 h were 8.1 (4.5; 18.7) mg/l, and serum half-life was 5.3 (5.1; 7.0) h. Steady-state concentrations during CI were 18.6 (13.3; 24.5) mg/l. The AUCs during either treatment were comparable and determined as 233 (202; 254) mg/l*h (IB) and 227 (182; 283) mg/l*h (CI), respectively. Four hours after IB, drug concentrations dropped below CI steady-state concentrations. CONCLUSION: Appropriate antibacterial concentrations of meropenem in patients with CRRT are easily achievable with CI. CI may be an effective alternative dosing regimen to IB. A prospective comparison of the clinical efficacy of the two dosage regimens is warranted.
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Antibacterianos/farmacocinética , Terapia de Substituição Renal , Tienamicinas/farmacocinética , Adulto , Idoso , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Feminino , Humanos , Unidades de Terapia Intensiva , Análise dos Mínimos Quadrados , Masculino , Meropeném , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
AIM: Bacterial translocation (BT) to mesenteric lymph nodes (MLN) in cirrhosis has been linked to impaired host defence. Phagocytosis by polymorphonuclear leucocytes (PMNLs) is the primary event in the killing of bacteria but has not been investigated in relation to the presence of BT. METHODS: Mesenteric lymph nodes were harvested sterile and assessed for BT by culture techniques. Study groups included ascitic cirrhotic rats (LC), healthy controls (Con) as well as portal-vein-ligated (PVL) rats 2 days (acute PVL with and without norfloxacin) or 3 weeks after surgery (chronic PVL). PMNLs were isolated from systemic blood and the capacity to phagocytose opsonized Escherichia coli was evaluated by FACS analysis. RESULTS: No BT was observed in Con and chronic PVL animals but 11/20 LC (55%) and six out of six acute PVL (100%) presented with BT. In the presence of BT, PMNL from PVL as well as LC rats showed significantly increased phagocytic activity as compared with controls. In contrast, PMNL from animals without BT, whether PVL or LC, exhibited phagocytic activity similar to those from control rats. The number of PMNLs involved in the phagocytic process was significantly increased only in portal-hypertensive rats with but not without BT as compared with controls. Norfloxacin did prevent BT in acute PVL animals, thereby correcting the increase in phagocytic capacity in PMNL. CONCLUSIONS: Cirrhosis per se is not associated with alterations of the phagocytic capacity of PMNL. The occurrence of BT, however, increases the phagocytic capacity of PMNL, being observed likewise in prehepatic portal hypertension, indicating an in vivo'priming' of PMNL by BT independent of cirrhosis.
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Translocação Bacteriana/imunologia , Escherichia coli/fisiologia , Hipertensão Portal/imunologia , Cirrose Hepática/imunologia , Neutrófilos/fisiologia , Fagocitose , Animais , Citometria de Fluxo , Linfonodos/microbiologia , Masculino , Mesentério , RatosRESUMO
BACKGROUND: The identification of clinical factors associated with negative blood cultures could help to avoid unnecessary blood cultures. C-reactive protein (CRP) is a well-established inflammation marker commonly used in the management of medical inpatients. METHODS: We studied the association of clinical factors, CRP levels and changes of CRP documented prior to blood culture draws with the absence of bacteremia for hospitalized medical patients. RESULTS: In the retrospective analysis of 710 blood cultures obtained from 310 medical inpatients of non-intensive-care wards during one year (admission blood cultures obtained in the emergency room were excluded), the following retrospectively available factors were the only independent predictors of blood cultures negative for obligate pathogens: a good clinical condition represented by the lowest of three general nursing categories (OR 4.2, 95% CI 1.8 - 9.5), a CRP rise > 50 mg/L documented before the blood culture draw (OR 2.0 95% CI 1.8-9.5) and any antibiotic treatment in the previous seven days (OR 2.0, 95% CI 1.1-3.5). CONCLUSION: Including the general clinical condition, antibiotic pre-treatment and a substantial rise of CRP into the decision, whether or not to obtain blood cultures from medical inpatients with a suspected infection, could improve the diagnostic yield.
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Infecções Bacterianas/diagnóstico , Biomarcadores/sangue , Sangue/microbiologia , Proteína C-Reativa/análise , Fatores de Risco , Adulto , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Técnicas Bacteriológicas , Humanos , Pacientes Internados , Modelos Logísticos , Estudos RetrospectivosRESUMO
OBJECTIVE: Genetic variants in the NOD2/CARD15 gene resulting in a diminished capacity to activate NF-kappaB in response to bacterial cell wall products have been associated with Crohn's disease (CD). Recently, we found an association between the variant Leu1007fsinsC of the NOD2/CARD15 gene (SNP13) and a significantly increased rate of transplant related mortality (TRM) due to intestinal and pulmonary complications in stem cell transplantation (SCT). To assess a possible contribution of variants in the NOD2/CARD15 gene to sepsis related mortality (SRM) we investigated 132 prospectively characterised, consecutive patients with sepsis. DESIGN AND PATIENTS: The three most common NOD2/CARD15 variants (Arg702Trp, Gly908Arg, and Leu1007fsinsC) were determined in 132 prospectively characterised patients with sepsis attended to three intensive care units at the University of Regensburg by Taqman PCR. NOD2/CARD15 genotype and major patients' characteristics were correlated with SRM. RESULTS: Patient groups with and without NOD2/CARD15 variants did not differ in their clinical characteristics such as median age, gender, reason for admission or APACHE score; however, SRM (day 30) was increased in patients with NOD2/CARD15 coding variants (42 vs. 31%) and was highest (57%) in 8 patients carrying the Leu1007fsinsC variant (p < 0.05). Multivariate analysis demonstrated the Leu1007fsinsC genetic variant as an independent risk factor for SRM. CONCLUSION: Our findings indicate a major role of NOD2/CARD15 coding variants for SRM. This may be indicative for a role of impaired barrier function and bacterial translocation in the pathophysiology of early sepsis related death.
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Mutação , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Sepse/mortalidade , APACHE , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Humanos , Unidades de Terapia Intensiva , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase , Estudos Prospectivos , Troca Gasosa Pulmonar , Fatores de RiscoRESUMO
BACKGROUND AND PURPOSE: Sepsis still represents a major medical challenge despite several advances in therapy. Most published data on sepsis have been derived from clinical trials evaluating new drugs and from international cohort studies. The aim of this study was to analyze risk factors, mortality and causative pathogens in a cohort of unselected patients with severe sepsis at a German university hospital and to compare the data with international cohorts and recently published therapeutic trials. PATIENTS AND METHODS: Between May 1999 and December 2002, all patients of the surgical and internal medicine intensive care units of a university medical center with newly manifested severe sepsis and at least one organ failure were recruited into the prospective observational study "Unicenter Sepsis Survey Regensburg" (USSR). RESULTS: 182 patients were included. The median age of the patients studied was 58 years, the median SAPS II amounted to 42, mortality at day 14 and day 30 was 25% and 34%, respectively. 48% of the patients developed sepsis due to an internal disease, 33% after surgical emergency interventions, and 19% after planned surgical interventions. Patients with surgical emergencies had higher SAPS II values and a worse outcome. 35% of all patients developed acute renal failure. 85% of the patients were treated with vasopressors, and 90% had to be ventilated mechanically. 58% of the patients had a probable and 38% a confirmed focal infection; in the final retrospective analysis, an infectious genesis proved to be unlikely in 4% of the patients. CONCLUSION: The characteristics of unselected patients with severe sepsis at the authors' institution are comparable to data from recently published sepsis studies with respect to mortality, severity of disease, and range of causative pathogens.
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Infecções Bacterianas/epidemiologia , Infecção Hospitalar/epidemiologia , Hospitais Universitários/estatística & dados numéricos , Choque Séptico/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/mortalidade , Estudos de Coortes , Comorbidade , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/mortalidade , Comparação Transcultural , Estudos Transversais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Fatores de Risco , Choque Séptico/diagnóstico , Choque Séptico/tratamento farmacológico , Choque Séptico/mortalidade , Taxa de Sobrevida , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Síndrome de Resposta Inflamatória Sistêmica/mortalidadeRESUMO
The family of Toll-like receptors (TLRs) is involved in the defense of an organism to microbial attack. TLR4-induced signaling is involved in infectious diseases, chronic inflammatory diseases and sepsis; therefore, we aimed at modulating TLR4-signaling via ligand-binding soluble receptors. Because recognition of microbial structures shows some species-specific traits, we specifically selected the mouse model for later in vivo studies. We first prepared the N-terminally Flag-tagged mouse (m) recombinant (r) soluble (s) fusion proteins mrsTLR4-IgGFc (T4Fc) and mrsMD-2 in Drosophila melanogaster Schneider 2 (S2) cells. The function of these molecules was tested by inhibition of synthesis of pro-inflammatory cytokines after stimulation of mouse macrophage RAW 264.7 cells with purified lipopolysaccharide (LPS). T4Fc alone had no inhibitory activity; however, a T4Fc/MD-2 complex blocked LPS activity. By analogy with 'cytokine traps', we then prepared a designer molecule (LPS-Trap) by fusing MD-2 to the C-terminus of soluble TLR4 via a flexible linker. LPS-Trap significantly inhibited TNF production by LPS-stimulated RAW 264.7 cells. Thus, the T4Fc/MD-2 complex as well as the LPS-Trap blocked LPS activity in vitro and might thus represent a new therapeutic option in sepsis by neutralization of TLR4-activating ligands.
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Antígenos Ly/metabolismo , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Western Blotting , Linhagem Celular , Células Cultivadas , Drosophila/citologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Antígeno 96 de Linfócito , Macrófagos/metabolismo , Camundongos , Testes de Precipitina , Proteínas/análise , Proteínas Recombinantes de Fusão , Transdução de Sinais , Solubilidade , Tenascina/metabolismo , Receptor 4 Toll-Like , Receptores Toll-Like , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
BACKGROUND: Acute bacterial meningitis is a medical emergency. Despite advances in the diagnosis and treatment it continues to have a high case-fatality rate and high rates of long-term neurologic sequelae. ETIOLOGY: Since the widespread use of the vaccine for Haemophilus influenzae type B, Streptococcus pneumoniae has replaced it as the most common cause of acute community-acquired bacterial meningitis in industrialized countries. The rising incidence of beta-lactam-resistant pneumococci has to be considered when choosing a regimen for empiric antibiotic therapy. DIAGNOSIS: The clinical diagnosis remains difficult, as absent clinical meningeal signs do not exclude bacterial meningitis. If bacterial meningitis is considered a possible diagnosis, empiric antibiotic therapy should be initiated without any delay. Prior blood cultures and, if not contraindicated, a lumbar puncture should be performed. Based on new evidence, a screening cranial computed tomography to rule out raised intracranial pressure prior to lumbar puncture is recommended only for patients with defined risk factors (age > 60 years; preexisting immunodeficiency, immunosuppression, or neurologic diseases; recent seizures; any pathologic finding in the neurologic examination other than meningism). TREATMENT: Empiric antibiotic therapy should be initiated before cranial computed tomography. Adjuvant dexamethasone therapy initiated with or prior to the antibiotic therapy reduces mortality and morbidity for patients with pneumococcal meningitis without increasing the rate of side effects.
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Meningites Bacterianas/diagnóstico , Doença Aguda , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Dexametasona/uso terapêutico , Resistência a Múltiplos Medicamentos , Emergências , Empirismo , Humanos , Lactente , Recém-Nascido , Meninges/microbiologia , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/microbiologia , Meningite Pneumocócica/diagnóstico , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/microbiologia , Pessoa de Meia-Idade , Fatores de Risco , Punção Espinal , Tomografia Computadorizada por Raios XRESUMO
We conducted a retrospective analysis of all bile specimens obtained for routine cultures from January 1995 through December 1999 at our tertiary care hospital. Results of microbiologic testing were linked to clinical parameters gathered by means of chart review. A total of 722 isolates were cultured from 345 of 454 bile specimens obtained from 288 individual patients. Prior receipt of a >7-day course of antibiotics (odds ratio [OR], 5.7), extensive leukocytosis (leukocyte count, >20,000 cells/microL) on admission (OR, 7.8), endoscopic or percutaneous biliary manipulation during the previous 14 days (OR, 2.9), and treatment in an internal medicine ward (OR, 2.5) were independent factors significantly associated (Pless-than-or-eq, slant.05) with recovery of Candida species from bile specimens. Culture of mezlocillin-resistant bacteria from bile specimens was independently associated with the specimen having been obtained >1 week after admission (OR, 3.8), lack of history of endoscopic biliary drainage (OR, 3.2), and high serum aspartate aminotransferase levels (>72 U/L) on admission (OR, 2.6). Prospective studies are warranted to evaluate accordingly adjusted empiric therapies for biliary infections.
Assuntos
Doenças dos Ductos Biliares/diagnóstico , Candidíase/diagnóstico , Bactérias/efeitos dos fármacos , Doenças dos Ductos Biliares/tratamento farmacológico , Doenças dos Ductos Biliares/microbiologia , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Resistência Microbiana a Medicamentos , Humanos , Mezlocilina/farmacologia , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Penicilinas/uso terapêutico , Prognóstico , Estudos RetrospectivosRESUMO
During the past 3 years new insights have been gained into the fundamental elements that underlie the pathogenesis of sepsis, and after years of frustrating failures, progress in the basic understanding of sepsis has translated into successful new therapies. These new treatment strategies have significantly improved the outcome of patients experiencing the puzzling syndrome of severe sepsis. More effective supportive therapies with early, goal-oriented therapy including volume resuscitation, catecholamine therapy and transfusion improve the chances for survival in septic shock. Novel endocrine management with hydrocortisone replacement therapy for relative adrenal insufficiency in septic shock patients and strict blood glucose control provide a survival advantage in critically ill patients. Administering appropriate antimicrobial therapy, nutritional support and ventilation protocols with low tidal volumes have now been shown to benefit septic patients. Finally, human recombinant activated protein C (drotrecogin alfa), which ameliorates sepsis-induced disseminated intravascular coagulation and exerts several other favourable effects on endothelial cells, has been shown to reduce mortality in patients with severe sepsis. On the basis of newly discovered pathophysiological mechanisms of sepsis, several other adjuvant therapies for sepsis are in various stages of preclinical and clinical development. Individualised and optimal supportive care with efforts to reverse the precipitating cause of sepsis remains the mainstay of therapy for severe sepsis. How these new and often expensive regimens will fit into the standard treatment approach to sepsis remains to be defined by future clinical investigations.
Assuntos
Antibacterianos/uso terapêutico , Sepse/tratamento farmacológico , Animais , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Humanos , Metanálise como Assunto , Modelos Biológicos , Estudos Multicêntricos como Assunto , Sepse/microbiologia , Sepse/fisiopatologia , Fatores de TempoRESUMO
OBJECTIVE: In chronic inflammatory diseases, serum levels of dehydroepiandrosterone (DHEA) sulfate (DHEAS) are low. Interestingly, several non-inflammatory diseases display similarly low levels of DHEAS which points to other inhibitory factors such as an activated sympathetic nervous system (SNS) (e.g. in patients with heart failure, fibromyalgia, or cancer cachexia). We aimed to identify the influence of the SNS tone on stimulated adrenal steroid secretion in 16 male and 12 female healthy subjects. METHODS: One group were given oral propranolol 2 h before a corticotropin-releasing hormone (CRH) test, and levels of adrenocorticotropin (ACTH), cortisol, 17-hydroxyprogesterone (17OHP), androstenedione, DHEA, and DHEAS were measured. RESULTS: Propranolol treatment decreased heart rate (by 20%), diastolic blood pressure (by 20%), and plasma ACTH, and increased serum cortisol, serum DHEAS, and the molar ratio of cortisol/17OHP, cortisol/DHEA, and DHEAS/DHEA similarly in female and male subjects. CONCLUSIONS: A beta-adrenergic influence seems to decrease CRH-stimulated cortisol in relation to ACTH and 17OHP, and decreases DHEAS in relation to DHEA. Although other workers have found beta-adrenergic stimulation of steroid secretion in cultured adrenocortical cells, the overall systemic influence of the SNS via beta-adrenoceptors seems to inhibit adrenal steroids under unstimulated and stimulated conditions. Sympathetic hyperactivity may be a common denominator for low levels of DHEAS in inflammatory and non-inflammatory diseases.