On the use of intravenous metronidazole for severe and complicated Clostridioides difficile infection: a review and meta-analysis

The European Society of Clinical Microbiology and Infectious Disease (ESCMID) has advised against the use of metronidazole for fulminant Clostridioides difficile (C. difficile) infection (CDI) in their latest guidelines. They suggest using oral vancomycin alone instead. This recommendation is based on a few retrospective studies, which have multiple biases. We evaluated the three studies that led ESCMID to advise against intravenous metronidazole for fulminant CDI and performed a meta-analysis. The meta-analysis revealed a mild (2.7%), not statistically significant (p=0.8) difference in mortality between the two groups. The high heterogeneity (I2= 89%) should also be noted. The decision to add or remove metronidazole should be discussed in the near future. In the meantime, combination therapy could be a cautious treatment for fulminant CDI.

Understanding the effect of heating rate on hydrothermal liquefaction: A comprehensive investigation from model compounds to a real food waste

Hydrothermal liquefaction (HTL) emerges as an efficient technology for converting food waste into biocrude. Among HTL parameters, the impact of heating rate is understudied. This study systematically explores its variation (5-115 K/min) on HTL performance using actual food waste and model compounds representing its constituents. Results revealed that an increase in heating rates significantly impacts HTL performances (+63 % biocrude and -34 % solid with food waste) with short residence times, as slower heating rates imply a longer overall time and a higher kinetic advancement of the reaction. Conversely, with longer residence times, the influence of heating rates becomes negligible, as kinetics during heating times are overshadowed by those at operating temperatures. A subtle effect of heating variation at extended residence time was observed only with carbohydrates. This research emphasizes the utility of a kinetic severity factor (KSF) as a valuable tool for simultaneously considering heating rates, operating times, and temperatures.

Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options

SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.

Intravenous Fosfomycin for Systemic Multidrug-Resistant Pseudomonas aeruginosa Infections

Human Pseudomonas infections have high morbidity and mortality rates. Pseudomonas bacteria can cause sepsis or septic shock; they produce biofilm and commonly exhibit a multidrug-resistant phenotype. The choice of antimicrobial therapy in many cases is challenging, and deep knowledge of clinical, microbiological, and pharmacological issues is required. Intravenous fosfomycin is being repurposed in a combination given its favorable pharmacokinetic/pharmacodynamic properties (a small molecule with favorable kinetic both in bloodstream infection and in deep-seated infections), antibiofilm activity, and its interesting synergistic effects with other antimicrobials. Recent literature on epidemiological, microbiological, pharmacological, and clinical data on intravenous fosfomycin therapy against Pseudomonas is herein reviewed and discussed.

A pediatric case of Chlamydia psittaci caused severe Acute Respiratory Distress Syndrome (ARDS) in Italy

BACKGROUND

This case of psittacosis in children, is the first described in literature, in Italy. This respiratory infection can be transmitted to humans from the inhalation of respiratory secretions, feces and plumage aerosol of infected birds (and other animals). Usually it can have an asymptomatic or paucisymptomatic course, and the onset is often flu-like, but in this case the child risked his life for a severe respiratory failure. This report is unique because in children psittacosis is rare, and always misdiagnosed, or could cause a delayed diagnosis because of lack of awareness among the paediatricians and physicians. Furthermore, psittacosis enters a differential diagnosis with SARS-COV2 infection because both diseases may determine dyspnea and atypical pneumonia, up to acute respiratory failure.

CASE PRESENTATION

This clinical case talks about a three-and-a-half-year-old male child affected by psittacosis (or ornithosis), with severe dyspnea and systemic symptoms who required oro-tracheal intubation for acute respiratory failure. The child had slept in a room at home, with some recently bought parrots affected by psittacosis. Initially the child was treated with empiric antibiotic therapy (i.v.ceftriaxone and teicoplanin), but after having isolated the DNA of the germ "Chlamydia psittaci" in both serological and through bronchoalveolar lavage (BAL), he was treated with targeted antibiotic therapy: tetracyclines (doxicillin).

CONCLUSIONS

Psittacosis is an extremely contagious disease, caused by an intracellular germ, called "Chlamydia psittaci", a Gram-negative bacterium, transmitted to humans in particular by infected birds, responsible for atypical pneumonia, with acute and chronic respiratory symptoms, sometimes with multi-organ failure and disseminated intravascular coagulation. Even if it is a rare respiratory disease among children, a good doctor must think about psittacosis as cause of respiratory symptoms (and not only flu or SARS-COV2), above all through a correct medical history, in order to provide a targeted antibiotic therapy. An interesting case of psittacosis in a child is being reported here, which has been treated successfully with doxycillin.

Bezlotoxumab in Patients with a Primary Clostridioides difficile Infection: A Literature Review

BACKGROUND

Nowadays, one of the main issues in the management of Clostridioides difficile infection (CDI) is the high rate of recurrences (rCDI), causing increased mortality and higher health care costs.

OBJECTIVES

To assess the available evidence on the use of bezlotoxumab for the prevention of rCDI during a first CDI episode.

METHODS

Published articles on bezlotoxumab during a primary CDI episode were identified through computerized literature searches with the search terms [(bezlotoxumab) AND (CDI) OR (Clostridioides difficile infection)] using PubMed and by reviewing the references of retrieved articles. PubMed was searched until 31 August 2022.

RESULTS

Eighty-eight studies were identified as published from December 2014 to June 2022. Five studies were included in this study, one was a phase III clinical trial and four were sub-analyses or extensions of the previous phase III clinical trial. In the phase III clinical trial, the subgroup analysis on the included primary CDI patients showed that 13.5% of patients receiving bezlotoxumab had an rCDI, whilst 20.9% of patients in the placebo group had an rCDI at the twelve weeks follow-up (absolute difference: -7.4).

CONCLUSIONS

Bezlotoxumab administration during the standard of care antibiotic therapy is effective and safe in reducing the rate of rCDI. Despite its high cost, evidence suggests considering bezlotoxumab in patients with a primary CDI episode. Further studies are needed to assess the benefit in specific subgroups of primary CDI patients and to define the risk factors to guide bezlotoxumab use.

Vaccine-Induced Subacute Thyroiditis (De Quervain’s) after mRNA Vaccine against SARS-CoV-2: A Case Report and Systematic Review

De Quervain’s thyroiditis, sometimes referred to as subacute thyroiditis (SAT), is the most common granulomatous disease of the thyroid, typically found after a viral infection in middle-aged women. The mRNA encoding for the angiotensin-converting enzyme-2 (ACE-2) receptor is expressed in follicular thyroid cells, making them a potential target for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Besides infection, SARS-CoV-2 vaccines have also been implicated in SAT pathogenesis. We present a case of a woman developing SAT following vaccination with Comirnaty by Pfizer Inc. (New-York, USA). We performed a systematic review of similar cases available in the literature to provide a better understanding of the topic. We searched the databases PubMed and Embase and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Patient records were then sorted according to the type of administered vaccine and a statistical analysis of the extracted data was performed. No statistically significant difference between mRNA vaccines and other vaccines in inducing SAT was found, nor was any found in terms of patient demographics, symptoms at presentation, initial, or follow-up blood tests. In our case report, we described the possible association between SARS-CoV-2 mRNA-based vaccine Comirnaty and SAT.

WSES/GAIS/WSIS/SIS-E/AAST global clinical pathways for patients with skin and soft tissue infections

Skin and soft-tissue infections (SSTIs) encompass a variety of pathological conditions that involve the skin and underlying subcutaneous tissue, fascia, or muscle, ranging from simple superficial infections to severe necrotizing infections.

Together, the World Society of Emergency Surgery, the Global Alliance for Infections in Surgery, the Surgical Infection Society-Europe, The World Surgical Infection Society, and the American Association for the Surgery of Trauma have jointly completed an international multi-society document to promote global standards of care in SSTIs guiding clinicians by describing reasonable approaches to the management of SSTIs.

An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting evidence was shared by an international task force with different clinical backgrounds.

Invasive cryptococcal disease in COVID-19: systematic review of the literature and analysis

During the Coronavirus Disease 2019 (COVID-19) pandemic, an increasing number of fungal infections associated with SARS-CoV-2 infection have been reported. Among them, cryptococcosis could be a life-threatening disease. We performed a Systematic Review (PRISMA Statement) of cryptococcosis and COVID-19 co-infection, case report/series were included: a total of 34 cases were found, then we added our case report. We collected patients' data and performed a statistical analysis comparing two groups of patients sorted by outcome: "dead" and "alive". Three cases were excluded for lack of information. To compare categorical data, we used a Fisher-exact test (α=0.05). To compare quantitative variables a U Mann-Whitney test was used (α=0.05), with a 95% Confidence Interval. A total of 32 co-infected patients were included in the statistical analysis. Mortality rate was 17/32 (53.1%): these patients were included in "dead" group, and 15/32 (46.9%) patients survived and were included in "alive" group. Overall, males were 25/32 (78.1%), the median age was 60 years (IQR 53-70) with non-statistically significant difference between groups (p=0.149 and p=0.911, respectively). Three variables were associated with mortality: ARDS, ICU admission and inadequate treatment. Overall, 21 out of 24 (87.5%) patients were in ARDS with a statistically significant difference among two groups (p=0.028). ICU admission for COVID-19 was observed in 18/26 (69.2%), more frequently among dead group (p=0.034). Finally, 15/32 (46.9%) patients had adequate treatment (amphotericin B + flucytosine for invasive cryptococcosis) mostly among alive patients (p=0.039). In conclusion, mortality due to cryptococcal infection among COVID-19 patients remains high but an early diagnosis and appropriate treatment could reduce mortality.

WSES/GAIS/SIS-E/WSIS/AAST global clinical pathways for patients with intra-abdominal infections

Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in hospitals worldwide. The cornerstones of effective treatment of IAIs include early recognition, adequate source control, appropriate antimicrobial therapy, and prompt physiologic stabilization using a critical care environment, combined with an optimal surgical approach. Together, the World Society of Emergency Surgery (WSES), the Global Alliance for Infections in Surgery (GAIS), the Surgical Infection Society-Europe (SIS-E), the World Surgical Infection Society (WSIS), and the American Association for the Surgery of Trauma (AAST) have jointly completed an international multi-society document in order to facilitate clinical management of patients with IAIs worldwide building evidence-based clinical pathways for the most common IAIs. An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting information was shared by an international task force from 46 countries with different clinical backgrounds. The aim of the document is to promote global standards of care in IAIs providing guidance to clinicians by describing reasonable approaches to the management of IAIs.

Influence of the Catalyst Particle Size on the Aqueous Phase Reforming of n-Butanol Over Rh/ZrO2

Butanol is a by-product obtained from biomass that can be valorized through aqueous phase reforming. Rh/ZrO₂ catalysts were prepared and characterized, varying the size of the support particles. The results showed a relatively mild effect of internal mass transport on butanol conversion. However, the influence of internal transport limitations on the product distribution was much stronger, promoting consecutive reactions, i.e., dehydrogenation, hydrogenolysis, and reforming of propane and ethane. Hydrogen consuming reactions, i.e., hydrogenolysis, were more strongly enhanced than hydrogen producing reactions due to internal concentration gradients. Large support particles deactivated faster, attributed to high concentrations of butyraldehyde inside the catalyst particles, enhancing deposit formation via aldol condensation reactions. Consequently, also the local butyric acid concentration was high, decreasing the local pH, enhancing Rh leaching. The influence of internal transfer limitation on product distribution and stability is discussed based on a reaction scheme with three main stages, i.e., (1) formation of liquid intermediates via dehydrogenation, (2) formation of gas via decarbonylation/decarboxylation reactions, and (3) hydrocarbon hydrogenolysis/reforming/dehydrogenation.

Robust Mesoporous CoMo/γ-Al2O3 Catalysts from Cyclodextrin-Based Supramolecular Assemblies for Hydrothermal Processing of Microalgae: Effect of the Preparation Method

Hydrothermal liquefaction (HTL) is a promising technology for the production of biocrude oil from microalgae. Although this catalyst-free technology is efficient under high-temperature and high-pressure conditions, the biocrude yield and quality can be further improved by using heterogeneous catalysts. The design of robust catalysts that preserve their performance under hydrothermal conditions will be therefore very important in the development of biorefinery technologies. In this work, we describe two different synthetic routes (i.e., impregnation and cyclodextrin-assisted one-pot colloidal approach), for the preparation in aqueous phase of six high surface area CoMo/γ-Al₂O₃ catalysts. Catalytic tests performed on the HTL of Nannochloropsis gaditana microalga indicate that solids prepared by the one-pot colloidal approach show higher hydrothermal stability and enhanced biocrude yield with respect to the catalyst-free test. The positive effect of the substitution of the block copolymer Tetronic T90R4 for Pluronic F127 in the preparation procedure was evidenced by diffuse reflectance UV-visible spectroscopy, X-ray diffraction, N₂-adsorption-desorption, and H₂-temperature-programmed reduction measurements and confirmed by the higher quality of the obtained biocrude, which exhibited lower oxygen content and higher-energy recovery equal to 62.5% of the initial biomass.