Definition of Opportunistic Infections in Immunocompromised Children on the Basis of Etiologies and Clinical Features: A Summary for Practical Purposes

Hypogammaglobulinemia Class G Is Present in Compensated and Decompensated Patients with Propionate Defects, Independent of Their Nutritional Status

Propionate defects (PDs) mainly include methylmalonic (MMA) and propionic acidemia (PA) defects. Lifelong PD patients progress from the compensated to the decompensated stages, the latter of which are characterized by life-threatening acidemia and hyperammonemia crises. PD patients can suffer immunocompromise, especially during the decompensation stage. There is a significant gap in the research regarding the humoral immune response in PD patients. Here, we analyzed serum immunoglobulin concentrations and hemograms across compensated and decompensated stages in PD patients. Nutritional status and crisis triggers of decompensation were also explored. Twenty patients were studied, and 25 decompensation events (DE) and 8 compensation events (CE) were recorded. Compared with those in the CE group, the IgG levels in the DE group (513.4 ± 244.5 mg/dL) were significantly lower than those in the CE group (860.8 ± 456.5 mg/dL) (p < 0.0087). The mean hemoglobin concentration was significantly lower in the DE group (11.8 g/dL) than in the CE group (13.4 g/dL) (p < 0.05). The most frequent (48%) possible decompensation trigger factor was infection. Most of the events were registered in eutrophic patients (87.9%), despite which 65.2% and 50% of patients who experienced decompensated and compensated events, respectively, presented with hypogammaglobulinemia G. These findings provide evidence of the immunodeficiency of PD patients, independent of their nutritional status. We suggest that PD patients be managed as immunocompromised independently of their nutritional status or metabolic state (compensated or decompensated).

Ianasi) P, Ianăşi C, Duda Seiman DM, Muntean D, Boeriu E. Advanced Photocatalytic Degradation of Cytarabine from Pharmaceutical Wastewaters

The need to develop advanced wastewater treatment techniques and their use has become a priority, the main goal being the efficient removal of pollutants, especially those of organic origin. This study presents the photo-degradation of a pharmaceutical wastewater containing Kabi cytarabine, using ultraviolet (UV) radiation, and a synthesized catalyst, a composite based on bismuth and iron oxides (BFO). The size of the bandgap was determined by UV spectroscopy, having a value of 2.27 eV. The specific surface was determined using the BET method, having a value of 0.7 m2 g-1. The material studied for the photo-degradation of cytarabine presents a remarkable photo-degradation efficiency of 97.9% for an initial concentration 0f 10 mg/L cytarabine Kabi when 0.15 g of material was used, during 120 min of interaction with UV radiation at 3 cm from the irradiation source. The material withstands five photo-degradation cycles with good results. At the same time, through this study, it was possible to establish that pyrimidine derivatives could be able to combat infections caused by Escherichia coli and Candida parapsilosis.

Infections in lung transplanted patients: A review

Lung transplantation can improve the survival of patients with severe chronic pulmonary disorders. However, the short- and long-term risk of infections can increase morbidity and mortality rates. A non-systematic review was performed to provide the most updated information on pathogen, host, and environment-related factors associated with the occurrence of bacterial, fungal, and viral infections as well as the most appropriate therapeutic options. Bacterial infections account for about 50% of all infectious diseases in lung transplanted patients, while viruses represent the second cause of infection accounting for one third of all infections. Almost 10% of patients develop invasive fungal infections during the first year after lung transplant. Pre-transplantation comorbidities, disruption of physical barriers during the surgery, and exposure to nosocomial pathogens during the hospital stay are directly associated with the occurrence of life-threatening infections. Empiric antimicrobial treatment after the assessment of individual risk factors, local epidemiology of drug-resistant pathogens and possible drug-drug interactions can improve the clinical outcomes.

Blood microbial signatures associated with mortality in patients with sepsis: A pilot study

Sepsis is a life-threatening illness caused by the dysregulated host response to infection. Nevertheless, our current knowledge of the microbial landscape in the blood of septic patients is still limited. Next-generation sequencing (NGS) is a sensitive method to quantitatively characterize microbiomes at various sites of the human body. In this study, we analyzed the blood microbial DNA of 22 adult patients with sepsis and 3 healthy subjects. The presence of non-human DNA was identified in both healthy and septic subjects. Septic patients had a markedly altered microbial DNA profile compared to healthy subjects over α- and β-diversity. Unexpectedly, the patients could be further divided into two subgroups (C1 and C2) based on β-diversity analysis. C1 patients showed much higher bacteria, viruses, fungi, and archaea abundance, and a higher level of α-diversity (Chao1, Observed and Shannon index) than both C2 patients and healthy subjects. The most striking difference was seen in the case of Streptomyces violaceusniger, Phenylobacterium sp. HYN0004, Caulobacter flavus, Streptomyces sp. 11-1-2, and Phenylobacterium zucineum, the abundance of which was the highest in the C1 group. Notably, C1 patients had a significantly poorer outcome than C2 patients. Moreover, by analyzing the patterns of microbe-microbe interactions in healthy and septic subjects, we revealed that C1 and C2 patients exhibited distinct co-occurrence and co-exclusion relationships. Together, our study uncovered two distinct microbial signatures in the blood of septic patients. Compositional and ecological analysis of blood microbial DNA may thus be useful in predicting mortality of septic patients.

Impact of Early Rejection Treatment on Infection Development in Kidney Transplant Recipients: A Propensity Analysis

Introduction

The impact of renal allograft rejection treatment on infection development has not been formally defined in the literature.

Methods

We conducted a retrospective cohort study of 185 rejection (case) and 185 nonrejection (control) kidney transplant patients treated at our institution from 2014 to 2020 to understand the impact of rejection on infection development. Propensity scoring was used to match cohorts. We collected data for infections within 6 months of rejection for the cases and 18 months posttransplant for controls.

Results

In 370 patients, we identified 466 infections, 297 in the controls, and 169 in the cases. Urinary tract infections (38.9%) and cytomegalovirus viremia (13.7%) were most common. Cumulative incidence of infection between the case and controls was 2.17 (CI 1.54-3.05); p < 0.001. There was no difference in overall survival (HR 0.90, CI 0.49-1.66) or graft survival (HR 1.27, CI 0.74-2.20) between the groups. There was a significant difference in overall survival (HR 2.28, CI 1.14-4.55; p = 0.019) and graft survival (HR 1.98, CI 1.10-3.56; p = 0.023) when patients with infection were compared to those without.

Conclusions

As previously understood, rejection treatment is a risk factor for subsequent infection development. Our data have defined this relationship more clearly. This study is unique, however, in that we found that infections, but not rejection, negatively impacted both overall patient survival and allograft survival, likely due to our institution's robust post-rejection protocols. Clinicians should monitor patients closely for infections in the post-rejection period and have a low threshold to treat these infections while also restarting appropriate prophylaxis.

Lower female survival from an opportunistic infection reveals progesterone-driven sex bias in trained immunity

Immune responses differ between females and males, although such sex-based variance is incompletely understood. Observing that bacteremia of the opportunistic pathogen Burkholderia gladioli caused many more deaths of female than male mice bearing genetic deficiencies in adaptive immunity, we determined that this was associated with sex bias in the innate immune memory response called trained immunity. Female attenuation of trained immunity varies with estrous cycle stage and correlates with serum progesterone, a hormone that decreases glycolytic capacity and recall cytokine secretion induced by antigen non-specific stimuli. Progesterone receptor antagonism rescues female trained immune responses and survival from controlled B. gladioli infection to magnitudes similar to those of males. These data demonstrate progesterone-dependent sex bias in trained immunity where attenuation of female responses is associated with survival outcomes from opportunistic infection.

Virtual Aunting and Public Health Emergencies: A Novel Approach to Sharing Public Health Guidance

Effective communication with the public is essential during health emergencies. As evident during the coronavirus disease 2019 (COVID-19) pandemic, the lack of effective public health communication with equity-deserving groups has contributed to higher morbidity and mortality than the non-racialized community. This concept paper will describe a grassroots community effort to provide culturally safe public health information to the East African community in Toronto at the beginning of the pandemic. Community members collaborated with The LAM Sisterhood to create a virtual aunt, Auntie Betty, and record voice notes with essential public health guidance in Swahili and Kinyarwanda. This manner of communicating with the East African community was well-received and has shown great potential as a tool to support effective communication efforts during public health emergencies that disproportionately impact Black and equity-deserving communities.

Infections in Inborn Errors of Immunity with Combined Immune Deficiency: A Review

Enhanced susceptibility to microbes, often resulting in severe, intractable and frequent infections due to usually innocuous organisms at uncommon sites, is the most striking feature in individuals with an inborn error of immunity. In this narrative review, based on the International Union of Immunological Societies' 2022 (IUIS 2022) Update on phenotypic classification of human inborn errors of immunity, the focus is on commonly encountered Combined Immunodeficiency Disorders (CIDs) with susceptibility to infections. Combined immune deficiency disorders are usually commensurate with survival beyond infancy unlike Severe Combined Immune Deficiency (SCID) and are often associated with clinical features of a syndromic nature. Defective humoral and cellular immune responses result in susceptibility to a broad range of microbial infections. Although disease onset is usually in early childhood, mild defects may present in late childhood or even in adulthood. A precise diagnosis is imperative not only for determining management strategies, but also for providing accurate genetic counseling, including prenatal diagnosis, and also in deciding empiric treatment of infections upfront before investigation reports are available.

Prophylaxis of Invasive Fungal Infection in Neonates: A Narrative Review for Practical Purposes

Candida albicans is the most frequent cause of invasive fungal disease in preterm and/or low birth weight neonates, followed by Candida parapsilosis, whilst infections from other species are rare. Considering the severity of the disease, associated with poor clinical signs and diagnostic difficulties, primary prophylaxis becomes relevant. This paper summarizes the pathogenesis and clinical presentation of invasive candidiasis in neonates, focusing on prophylaxis. For late onset invasive disease, e.g., those occurring after the 3rd (or 7th according to some definitions) day of life possible approaches are the use of fluconazole, recommended in case of weight <1000 g or <1500 g if the local incidence of invasive candidiasis is higher than 2%, or the use of nystatin (for patients < 1500 g). Micafungin must be used in case of colonization by Candida auris, or in centers with a high prevalence of this pathogen. Concurrently, correct management of the central venous catheter and isolation procedures, with special regard to patients colonized by resistant strains, are fundamental. Other approaches such as reduced use of H₂ blockers and broad-spectrum antibiotics (e.g., 3rd generation cephalosporins or carbapenems) and promotion of breast feeding proved useful. Reduction of early-onset infections (those occurring in the first 3 days of life) can also be obtained by treating maternal vulvo-vaginal candidiasis, which can represent a fastidious problem during pregnancy. In this case, topic azoles (the only recommendable treatment) can represent a kind of "prophylaxis" of early neonatal candidiasis. However, it must always be remembered that prophylaxis reduces the risk of invasive candidiasis but can not completely eliminate its occurrence, with the parallel risk of selecting for antifungal-resistant strains. Clinicians must maintain a high level of suspicion to start an appropriate therapy and strict epidemiological surveillance to identify the occurrence of clusters and the appearance of strains resistant to prophylaxis.

Infections following rejection therapies in kidney and liver transplant recipients

INTRODUCTION

Infections are known complications of solid-organ transplant. Treatment for rejection may increase risk of infection. We aimed to study frequency of infection and identify the risk factors for infections in solid organ transplant (SOT) (liver and kidney) recipients treated for rejection.

METHODS

This is a retrospective chart review of all liver and kidney transplant recipients treated for rejection at our institution from 2014 to 2020. We collected information on episodes of acute rejection in the first year of transplant and infections within 6 months following rejection treatment.

RESULTS

We identified 257 transplant patients treated for rejection. One hundred twelve (43.6%) developed infections, with a total of 226 infections. Urinary tracts infections were the most common, 72 (31.9%), followed by cytomegalovirus viremia in 37 (16.4%), bacteremia in 24 (10.6%), and BK virus in 14 (6.2%). Female sex (p = .047), elevated neutrophil count at rejection (p = .002), and increased number of rejection episodes (p = .022) were predictors of infection in kidney and simultaneous liver-kidney recipients. No specific type of induction or rejection therapy was identified as a risk factor for infection, likely due to the prophylaxis protocols at our institution. Infection post rejection treatment was associated with higher graft loss (p = .021) and mortality (p = .031) in kidney transplant recipients.

CONCLUSIONS

Infections are common complications after treatment of SOT rejection. Female gender, higher neutrophil at time of rejection, and increased numbers of rejection episodes were predictors of infections after rejection in simultaneous liver-kidney and kidney transplant patients. Infections were predictors of graft loss at 6 months and mortality at any point in follow-up in kidney transplant patients.

Reproductive Desire in Women Living with HIV/AIDS with Serodiscordant Partners

OBJECTIVE

To estimate the prevalence and factors associated with reproductive desire in a sample of women living with HIV/AIDS (WLHA) with serodiscordant partners.

STUDY DESIGN

Between September 2015 and August 2016, a cross-sectional study was conducted among 110 WLHA from HIV/AIDS treatment services and non-governmental organizations. An interview was conducted using a structured questionnaire to collect sociodemographic data, reproductive desire, and potential predictor variables. Poisson regression was used to analyze the factors associated with reproductive desire in the sample.

RESULTS

The prevalence of reproductive desire was 32.7% (95% Confidence Interval: % CI: 24.7-42.0%). In regression analysis, we observed an association between reproductive desire and the following variables: age < 30 years; relationship time < 2 years; reproductive desire for the partner; and absence of children.

CONCLUSIONS

The prevalence of reproductive desire in the investigated sample was relatively high. Young age and reproductive desire for the partner were the main associated factors.

An Italian survey on the microbiological safety of toys containing aqueous media

AIMS

The purpose of the present investigation is to fill the current gap in information regarding the microbiological quality of toys containing aqueous media and the related risks for users.

METHODS

Over eighteen years, a total of 491 sealed toys containing aqueous media were analysed using conventional microbial culture methods. In addition, molecular methods (PCR/nested RT-PCR, followed by Sanger sequencing) were employed to test for enteric viruses (enteroviruses and adenoviruses) in a subset of toys; subsequently, the infectivity of the positive samples was tested on cell cultures.

RESULTS

Of the examined toys, 23.8% were noncompliant with the limits of the European guideline. The most frequently exceeded limits were those for Aerobic bacteria (84.6%), and Pseudomonas aeruginosa (29.9%). Other opportunistic bacterial species that were frequently detected were Stenotrophomonas maltophilia, Pseudomonas fluorescens, Burkholderia cepacia Sphingomonas paucimobilis and Comamonas acidovorans. In a subset of 28 samples, adenovirus (25%) and enterovirus (11%) genome was also found to be present, although the samples with viral positivity did not show infectivity after inoculation on appropriate cell monolayers.

CONCLUSIONS

The results indicate a condition of microbial exposure related to the use of toys containing aqueous media.

SIGNIFICANCE AND IMPACT OF STUDY

The investigation highlights the need for more stringent monitoring during the production, packaging and storage of toys containing aqueous matrices in order to safeguard children's health.

Chronic Rhinosinusitis and Alzheimer's Disease-A Possible Role for the Nasal Microbiome in Causing Neurodegeneration in the Elderly

Among millions of sufferers of chronic rhinosinusitis (CRS), the challenge is not only constantly coping with CRS-related symptoms, such as congested nose, sinus pain, and headaches, but also various complications, such as attention difficulties and possible depression. These complications suggest that neural activity in the central nervous system may be altered in those patients, leading to unexpected conditions, such as neurodegeneration in elderly patients. Recently, some studies linked the presence of CRS and cognitive impairments that could further develop into Alzheimer’s disease (AD). AD is the leading cause of dementia in the elderly and is characterised by progressive memory loss, cognitive behavioural deficits, and significant personality changes. The microbiome, especially those in the gut, has been recognised as a human organ and plays an important role in the development of various conditions, including AD. However, less attention has been paid to the microbiome in the nasal cavity. Increased nasal inflammatory responses due to CRS may be an initial event that changes local microbiome homeostasis, which may further affect neuronal integrity in the central nervous system resulting in AD. Evidence suggests a potential of β-amyloid deposition starting in olfactory neurons, which is then expanded from the nasal cavity to the central nervous system. In this paper, we reviewed currently available evidence that suggests this potential mechanism to advise the need to investigate the link between these two conditions.

Raoultella terrigena: Current state of knowledge, after two recently identified clinical cases in Eastern Europe

Raoultella terrigena is a rarely found opportunistic pathogen that can cause healthcare-associated infections with high mortality. It is important to differentiate it from Klebsiella species.

Differential Markers of Bacterial and Viral Infections in Children for Point-of-Care Testing

Children suffering from infectious diseases, both bacterial and viral, are often treated with empirical antibiotics. Keeping in mind both the menace of microorganisms and antibiotic toxicity, it is imperative to develop point-of-care testing (POCT) to discriminate bacterial from viral infections, and to define indications for antibiotic treatment. This article reviews potential protein biomarkers and host-derived gene expression signatures for differentiating between bacterial and viral infections in children, and focuses on emerging multiplex POCT devices for the simultaneous detection of sets of protein biomarkers or streamlined gene expression signatures that may provide rapid and cost-effective pathogen-discriminating tools.

Bacteria and viruses activate or inhibit different signaling pathways in the cells they infect, and further give rise to different host transcriptional signatures as well as to unique protein biomarkers.

Many of the newly evaluated protein biomarkers, especially in combination, have better discriminative value for distinguishing between bacterial and viral infections than the biomarkers that are currently used for examining infections in children.

The transcriptomes of children undergo remarkable changes when they are infected by different types of bacteria and viruses. Approaches based on host-derived DNA/RNA signatures can accurately discriminate bacterial from viral infections.

Emerging multiplex POCT techniques allow simultaneous testing of protein- or gene-based biomarkers in an outpatient setting.

The Postbiotic Activity of Lactobacillus paracasei 28.4 Against Candida auris

Candida auris has emerged as a medically important pathogen with considerable resistance to antifungal agents. The ability to produce biofilms is an important pathogenicity feature of this species that aids escape of host immune responses and antimicrobial agents. The objective of this study was to verify antifungal action using in vitro and in vivo models of the Lactobacillus paracasei 28.4 probiotic cells and postbiotic activity of crude extract (LPCE) and fraction 1 (LPF1), derived from L. paracasei 28.4 supernatant. Both live cells and cells free supernatant of L. paracasei 28.4 inhibited C. auris suggesting probiotic and postbiotic effects. The minimum inhibitory concentration (MIC) for LPCE was 15 mg/mL and ranges from 3.75 to 7.5 mg/mL for LPF1. Killing kinetics determined that after 24 h treatment with LPCE or LPF1 there was a complete reduction of viable C. auris cells compared to fluconazole, which decreased the initial inoculum by 1-logCFU during the same time period. LPCE and LPF1 significantly reduced the biomass (p = 0.0001) and the metabolic activity (p = 0.0001) of C. auris biofilm. There was also a total reduction (~10⁸ CFU/mL) in viability of persister C. auris cells after treatment with postbiotic elements (p < 0.0001). In an in vivo study, injection of LPCE and LPF1 into G. mellonella larvae infected with C. auris prolonged survival of these insects compared to a control group (p < 0.05) and elicited immune responses by increasing the number of circulating hemocytes and gene expression of antimicrobial peptide galiomicin. We concluded that the L. paracasei 28.4 cells and postbiotic elements (LPCE and LPF1) have antifungal activity against planktonic cells, biofilms, and persister cells of C. auris. Postbiotic supplementation derived from L. paracasei 28.4 protected G. mellonella infected with C. auris and enhanced its immune status indicating a dual function in modulating a host immune response.

Mould Infections of Traumatic Wounds: A Brief Narrative Review

Mould infections may follow traumatic injuries, with direct fungal inoculum in the site of injury and subsequent angioinvasion, possibly resulting in tissue necrosis and systemic dissemination. The pathogenesis of mould infections following trauma injuries presents unique features compared with classical mould infections occurring in neutropenic or diabetic patients, because a large fraction of post-traumatic mould infections is observed in previously healthy individuals. Most of the published clinical experience and research on mould infections following traumatic injuries regards soldiers and infections after natural disasters. However, following trauma and soil contamination (e.g., agricultural or automotive injuries) other immunocompetent individuals may develop mould infections. In these cases, delays in correct diagnosis and treatment may occur if pertinent signs such as necrosis and absent or reduced response to antibacterial therapy are not promptly recognized. Awareness of mould infections in at-risk populations is needed to rapidly start adequate laboratory workflow and early antifungal therapy in rapidly evolving cases to improve treatment success and reduce mortality.