Authors:Patricia Patricio, José Artur Paiva and Luís Miguel Borrego
Sepsis leads to a systemic immune response, and despite the progress of modern medicine, it is still responsible for a high mortality rate.
The immune response to sepsis is dependent on the innate and adaptive immune systems. The first line is the innate system, which requires complex and multiple pathways in order to eliminate the invading threats. The adaptive responses start after the innate response. The cell-mediated arm of CD4+ and CD8+ T and B cells is the main responsible for this response.
A coordinated cytokine response is essential for the host immune response. A dysregulated response can lead to a hyperinflammatory condition (cytokine storm). This hyperinflammation leads to neutrophils activation and may also lead to organ dysfunction. An imbalance of this response can increase the anti-inflammatory response, leading to compensatory anti-inflammatory response syndrome (CARS), persistent inflammation-immunsupression, catabolism syndrome (PICS), and, above all, an immune paralysis stat.
This immune paralysis leads to opportunistic infections, Candida species being one of the emerging microorganisms involved. The host immune response is different for bacterial or Candida sepsis.
Immune responses for bacterial and Candida sepsis are described in this paper.
Authors:N. von Allmen, K. Gorzelniak, O. Liesenfeld, M. Njoya, J. Duncan, E. M. Marlowe, T. Hartel, A. Knaust, B. Hoppe and M. Walter
Rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) colonization status facilitates isolation and decolonization and reduces MRSA infections. Liquid but not dry swabs allow fully automated detection methods. However, the accuracy of culture and polymerase chain reaction (PCR) using liquid and dry swabs has not been analyzed. We compared different swab collection systems for routine nasal–throat MRSA screening in patients admitted to a tertiary care trauma center in Germany. Over 3 consecutive months, dry swabs (month 1), ESwabs (month 2), or MSwabs (month 3) were processed using Cepheid GeneXpert, Roche cobas and BD-MAX™ MRSA tests compared to chromogenic culture. Among 1680 subjects, the MRSA detection rate using PCR methods did not differ significantly between dry swabs, ESwab, and MSwab (6.0%, 6.2%, and 5.3%, respectively). Detection rates using chromogenic culture were 2.9%, 3.9%, and 1.9%, using dry, ESwab, and MSwab, respectively. Using chromogenic culture as the “gold standard”, negative predictive values for the PCR tests ranged from 99.2–100%, and positive predictive values from 33.3–54.8%. Thus, efficient and accurate MRSA screening can be achieved using dry, as well as liquid E- or MSwab, collection systems. Specimen collection using ESwab or MSwab facilitates efficient processing for chromogenic culture in full laboratory automation while also allowing molecular testing in automated PCR systems.
Authors:Hagen Frickmann, Andreas Hahn, Stefan Berlec, Johannes Ulrich, Moritz Jansson, Norbert Georg Schwarz, Philipp Warnke and Andreas Podbielski
Introduction: Escherichia coli and Staphylococcus aureus are important causes of severe diseases like blood stream infections. This study comparatively assessed potential differences in their impact on disease severity in local and systemic infections.
Methods: Over a 5-year interval, patients in whom either E. coli or S. aureus was detected in superficial or primary sterile compartments were assessed for the primary endpoint death during hospital stay and the secondary endpoints duration of hospital stay and infectious disease as the main diagnosis.
Results: Significance was achieved for the impacts as follows: Superficial infection with S. aureus was associated with an odds ratio of 0.27 regarding the risk of death and of 1.42 regarding infectious disease as main diagnosis. Superficial infection with E. coli was associated with a reduced duration of hospital stay by −2.46 days and a reduced odds ratio of infectious diseases as main diagnosis of 0.04. The hospital stay of patients with E. coli was increased due to third-generation cephalosporin and ciprofloxacin resistance, and in the case of patients with S. aureus due to tetracycline and fusidic acid resistance.
Conclusions: Reduced disease severity of superficial infections due to both E. coli and S. aureus and resistance-driven prolonged stays in hospital were confirmed, while other outcome parameters were comparable.
Authors:E. Feoli, P. Ganis, J. J. Ibáñez and R. Pérez-Gómez
In this paper, we want to support the idea of using a family of indices of similarity, that we call the Simpson's family indices or nestedness-based similarity functions (NBSF) for comparing operational geographic units (OGUs) (phytosociological relevés, animal traps, watersheds, administrative units, industrial areas, islands etc.). In these cases, similarity-dissimilarity depends, in addition to factors that induce replacement, also on factors that produce reduction or increment in the number of features within the same typology of OGUs (e.g., extent, reduction of fertility, anthropogenic pressure etc.). To keep into consideration this aspect, the indices are defined to be equal to 1 when the OGUs are completely nested. The results of the application to four simulated data sets prove that, when the data set does not show clear nested pattern, the use of NBSF produces results similar to the nestedness-free similarity functions, however since NBSF clearly detect nested situations, we should prefer their use in the circumstances where we think important to put in evidence nestedness. In conclusion, we support the idea of using both types of indices in order to improve the knowledge about the structure of any data set.
Authors:Carina Gottwald, Norbert Georg Schwarz and Hagen Frickmann
Introduction: The study was performed to estimate the prevalence and determinants of occurrence of sexually transmitted infections (STIs) in paratroopers and navy soldiers by anonymously analyzing medical records from the medical departments of two large German barracks in order to assess the need for medical STI prevention.
Methods: Medical records from 80 paratroopers and 80 navy soldiers were screened for records of STI. Results were anonymously collected next to information on risk factors, as well as diagnostic and therapeutic management, and comparatively assessed.
Results: Proportions of suspected STIs were 17.5% and 20%, and proportions of diagnosed STIs were 13.9% and 11.3% for paratroopers and navy soldiers, respectively. Chlamydia trachomatis, human papillomavirus, and genital scabies were observed in paratroopers and navy soldiers, while Gardnerella vaginalis, herpes simplex virus, Molluscum contagiosum virus, Neisseria gonorrhoeae, and Trichomonas vaginalis were additionally identified in navy soldiers.
Conclusions: Although clinical hints for STIs were frequently observed, clinical management was usually restricted to syndrome-based antibiotic treatment without detailed diagnostic workup, leaving room for procedural improvement. Ongoing need for medical STI prevention in the military could be confirmed.
We briefly complement Endrédi et al. (2019) forum paper from terrestrial animal ecological points of view. We discuss the origins of trait-based approach, challenges of trait classifications, and we provide an example of a commonly used trait, body size.
Authors:Ainoosh Golpour, Stefan Bereswill and Markus M. Heimesaat
Antimicrobial multidrug-resistance (MDR) constitutes an emerging threat to global health and makes the effective prevention and treatment of many, particularly severe infections challenging, if not impossible. Many antibiotic classes have lost antimicrobial efficacy against a plethora of infectious agents including bacterial species due to microbial acquisition of distinct resistance genes. Hence, the development of novel anti-infectious intervention strategies including antibiotic-independent approaches is urgently needed. Vitamins such as vitamin D and vitamin D derivates might be such promising molecular candidates to combat infections caused by bacteria including MDR strains. Using the Pubmed database, we therefore performed an in-depth literature survey, searching for publications on the antimicrobial effect of vitamin D directed against bacteria including MDR strains. In vitro and clinical studies between 2009 and 2019 revealed that vitamin D does, in fact, possess antimicrobial properties against both Gram-positive and Gram-negative bacterial species, whereas conflicting results could be obtained from in vivo studies. Taken together, the potential anti-infectious effects for the antibiotic-independent application of vitamin D and/or an adjunct therapy in combination with antibiotic compounds directed against infectious diseases such as tuberculosis, H. pylori infections, or skin diseases, for instance, should be considered and further investigated in more detail.
Authors:Ralf Ignatius, Robert Neuber, Heike Kietzmann, Christiane Berg, Thilo Wenzel, Jörg Fuhrmann and Michael Müller
This study aimed at evaluating in outpatients an algorithm for the laboratory diagnosis of Clostridioides (Clostridium) difficile infection (CDI), i.e., enzyme immunoassays (EIAs) detecting bacterial glutamate dehydrogenase (GDH) and toxin A/B, followed by polymerase chain reaction (PCR) analyses of samples with discordant EIA results.
In total, 9802 examinations of stool samples by GDH and toxin EIAs performed in 7263 outpatients and 488 inpatients were analyzed retrospectively. Samples with discordant EIA results had been tested by a commercially available PCR assay detecting genes of the C. difficile-specific triose phosphate isomerase (tpi) and toxin B (tcdB).
Concordant EIA results (686 C. difficile-positive, 8121 negative) were observed for 8807 (89.8%; 95% CI, 89.2–90.4%) samples. Of 958 samples with discordant EIA results, 895 were analyzed using PCR and 580 of 854 GDH-positive/borderline, toxin-negative samples (67.9%; 95% CI, 64.7–71.0%) were positive for tpi and tcdB, while 274 samples (32.1%; 95% CI, 29.0–35.3%) were tcdB-negative. In contrast, 35 of 41 GDH-negative, toxin-positive/borderline samples (85.4%; 95% CI, 71.2–93.5%) were tcdB-negative. Still, 6 samples (14.6%; 95% CI, 6.5–28.8%) yielded positive PCR results for both genes.
In conclusion, around 90% of the samples were analyzed appropriately by only applying EIAs. Approximately one third of the PCR-analyzed samples were tcdB-negative; thus, patients most likely did not require CDI treatment.
Authors:Katrin Bote, Judith Pöppe, Susanne Riede, Gerhard Breves and Uwe Roesler
Glyphosate (N-(phosphonomethyl)glycine) is the most-used herbicide worldwide. Many studies in the past have shown that residues of the herbicide can be found in many cultivated plants, including those used as livestock feed. Sensitivity to glyphosate varies with bacteria, particularly those residing in the intestine, where microbiota is exposed to glyphosate residues. Therefore, less susceptible pathogenic isolates could have a distinct advantage compared to more sensitive commensal isolates, probably leading to dysbiosis.
To determine whether the ruminal growth and survival of pathogenic Escherichia coli or Salmonella serovar Typhimurium are higher when glyphosate residues are present in the feed, an in vitro fermentation trial with a “Rumen Simulation System” (RUSITEC) and a glyphosate-containing commercial formulation was performed.
Colony forming units of E. coli and Salmonella ser. Typhimurium decreased steadily in all fermenters, regardless of the herbicide application. Minimum inhibitory concentrations of the studied Salmonella and E. coli strains did not change, and antibiotic susceptibility varied only slightly but independent of the glyphosate application.
Overall, application of the glyphosate-containing formulation in a worst-case concentration of 10 mg/L neither increased the abundance for the tested E. coli and Salmonella strain in the in vitro fermentation system, nor promoted resistance to glyphosate or antibiotics.
Authors:Soraya Mousavi, Stefan Bereswill and Markus M. Heimesaat
Humans have lost their vitamin C-synthesizing capacities during evolution. Therefore, the uptake of this essential compound from external sources is mandatory in order to prevent vitamin C-deficient conditions resulting in severe morbidities such as scurvy. The potent antioxidant, immunomodulatory, and antiinfectious effects of vitamin C are known since the 1930s. We here (i) review the impact of vitamin C on innate and adaptive immune functions, (ii) provide an overview of its antimicrobial, antibacterial, antiviral, antiparasitic, and antifungal properties, and finally, (iii) discuss vitamin C as an adjunct treatment option for the combat of human infections by bacteria, particularly by emerging multidrug-resistant species.