Cellular stress promotes NOD1/2-dependent inflammation via the endogenous metabolite sphingosine-1-phosphate.

Cellular stress has been associated with inflammation, yet precise underlying mechanisms remain elusive. In this study, various unrelated stress inducers were employed to screen for sensors linking altered cellular homeostasis and inflammation. We identified the intracellular pattern recognition receptors NOD1/2, which sense bacterial peptidoglycans, as general stress sensors detecting perturbations of cellular homeostasis. NOD1/2 activation upon such perturbations required generation of the endogenous metabolite sphingosine-1-phosphate (S1P). Unlike peptidoglycan sensing via the leucine-rich repeats domain, cytosolic S1P directly bound to the nucleotide binding domains of NOD1/2, triggering NF-κB activation and inflammatory responses. In sum, we unveiled a hitherto unknown role of NOD1/2 in surveillance of cellular homeostasis through sensing of the cytosolic metabolite S1P. We propose S1P, an endogenous metabolite, as a novel NOD1/2 activator and NOD1/2 as molecular hubs integrating bacterial and metabolic cues.

Neglect scoring modifications in the National Institutes of Health Stroke Scale improve right hemisphere stroke lesion volume prediction.

BACKGROUND: The National Institutes of Health Stroke Scale (NIHSS) does not equitably assess stroke severity in the two cerebral hemispheres. By attributing a maximum of two points for neglect and seven for language, it undervalues right hemisphere deficits. We aimed to investigate if NIHSS equally predicts right hemisphere lesion volumes in patients with and without neglect, and if a modification of the neglect scoring rules could increase its predictive capacity. METHODS: We analyzed a prospective cohort of acute right middle cerebral artery ischemic stroke patients. First, we calculated the correlation between NIHSS scores and lesion volume and analyzed the partial correlation of neglect. Then, we applied different modifications in the neglect scoring rules and investigated how they interfered with lesion volume predictive capacity. RESULTS: A total of 162 ischemic stroke patients were included, 108 with neglect and 54 without. The correlation between lesion volume and NIHSS was lower in patients with neglect (r = 0.540 vs. r = 0.219, p = 0.004) and neglect was a statistically significant covariate in the partial correlation analysis between NIHSS and lesion volume (p = 0.017). With the neglect score tripled and with the duplication or triplication of all neglect modalities, the correlation was significantly higher than with the standard NIHSS (p = 0.043, p = 0.005, p = 0.001, respectively). With these modifications, neglect was no longer a significant covariable in the partial correlation between lesion volume and NIHSS. CONCLUSION: A modification of NIHSS neglect scoring might improve the scale's capacity to predict lesion volume.

Development of FluoAHRL: A Novel Synthetic Fluorescent Compound That Activates AHR and Potentiates Anti-Inflammatory T Regulatory Cells.

Aryl Hydrocarbon Receptor (AHR) ligands, upon binding, induce distinct gene expression profiles orchestrated by the AHR, leading to a spectrum of pro- or anti-inflammatory effects. In this study, we designed, synthesized and evaluated three indole-containing potential AHR ligands (FluoAHRL: AGT-4, AGT-5 and AGT-6). All synthesized compounds were shown to emit fluorescence in the near-infrared. Their AHR agonist activity was first predicted using in silico docking studies, and then confirmed using AHR luciferase reporter cell lines. FluoAHRLs were tested in vitro using mouse peritoneal macrophages and T lymphocytes to assess their immunomodulatory properties. We then focused on AGT-5, as it illustrated the predominant anti-inflammatory effects. Notably, AGT-5 demonstrated the ability to foster anti-inflammatory regulatory T cells (Treg) while suppressing pro-inflammatory T helper (Th)17 cells in vitro. AGT-5 actively induced Treg differentiation from naïve CD4+ cells, and promoted Treg proliferation, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) expression and interleukin-10 (IL-10) production. The increase in IL-10 correlated with an upregulation of Signal Transducer and Activator of Transcription 3 (STAT3) expression. Importantly, the Treg-inducing effect of AGT-5 was also observed in human tonsil cells in vitro. AGT-5 showed no toxicity when applied to zebrafish embryos and was therefore considered safe for animal studies. Following oral administration to C57BL/6 mice, AGT-5 significantly upregulated Treg while downregulating pro-inflammatory Th1 cells in the mesenteric lymph nodes. Due to its fluorescent properties, AGT-5 could be visualized both in vitro (during uptake by macrophages) and ex vivo (within the lamina propria of the small intestine). These findings make AGT-5 a promising candidate for further exploration in the treatment of inflammatory and autoimmune diseases.

Characterization and Investigation of Risk Factors for Late-Relapsing Hepatitis After Yellow Fever.

BACKGROUND: Late-relapsing hepatitis after yellow fever (LHep-YF) during the convalescent phase of the disease has been described during recent yellow fever (YF) outbreaks in Brazil. LHep-YF is marked by a rebound in liver enzymes and nonspecific clinical manifestations around 46-60 days after YF symptom onset. METHODS: Here we have characterized the clinical course and risk factors for LHep-YF using data from a representative cohort of patients who survived YF in Brazil, 2017-2018. A total of 221 YF-positive patients were discharged from the infectious disease reference hospital in Minas Gerais and were followed up at 30, 45, and 60 days post-symptom onset. RESULTS: From 46 to 60 days post-symptom onset, 16% of YF patients (n = 36/221) exhibited a rebound of aminotransferases (aspartate aminotransferase or alanine aminotransferase >500 IU/L), alkaline phosphatase, and total bilirubin levels. Other etiologies of liver inflammation such as infectious hepatitis, autoimmune hepatitis, and metabolic liver disease were ruled out. Jaundice, fatigue, headache, and low platelet levels were associated with LHep-YF. Demographic factors, clinical manifestations, laboratory tests, ultrasound findings, and viral load during the acute phase of YF were not associated with the occurrence of LHep-YF. CONCLUSIONS: These findings provide new data on the clinical course of Late-relapsing hepatitis during the convalescent phase of YF and highlight the need for extended patient follow-up after acute YF.

Serum soluble mediators as prognostic biomarkers for morbidity, disease outcome, and late-relapsing hepatitis in yellow fever patients.

This study described a soluble mediator storm in acute Yellow Fever/YF infection along the kinetics timeline towards convalescent disease. The analyses of the YF Viral RNAnemia, chemokines, cytokines, and growth factors were performed in YF patients at acute/(D1-15) and convalescent/(D16-315) phases. Patients with acute YF infection displayed a trimodal viremia profile spreading along D3, D6, and D8-14. A massive storm of mediators was observed in acute YF. Higher levels of mediators were observed in YF with higher morbidity scores, patients under intensive care, and those progressing to death than in YF patients who progress to late-relapsing hepatitis/L-Hep. A unimodal peak of biomarkers around D4-6 with a progressive decrease towards D181-315 was observed in non-L-Hep patients, while a bimodal pattern with a second peak around D61-90 was associated with L-Hep. This study provided a comprehensive landscape of evidence that distinct immune responses drive pathogenesis, disease progression, and L-Hep in YF patients.

Organotypic hippocampal culture model reveals differential responses to highly similar Zika virus isolates.

INTRODUCTION: Zika virus (ZIKV) caused an outbreak in Brazil, in 2015, being associated to microcephaly. ZIKV has a strong neurotropism leading to death of infected cells in different brain regions, including the hippocampus, a major site for neurogenesis. The neuronal populations of the brain are affected differently by ZIKV from Asian and African ancestral lineages. However, it remains to be investigated whether subtle variations in the ZIKV genome can impact hippocampus infection dynamics and host response. OBJECTIVE: This study evaluated how two Brazilian ZIKV isolates, PE243 and SPH2015, that differ in two specific missense amino acid substitutions, one in the NS1 protein and the other in the NS4A protein, affect the hippocampal phenotype and transcriptome. METHODS: Organotypic hippocampal cultures (OHC) from infant Wistar rats were infected with PE243 or SPH2015 and analyzed in time series using immunofluorescence, confocal microscopy, RNA-Seq and RT-qPCR. RESULTS: Unique patterns of infection and changes in neuronal density in the OHC were observed for PE243 and SPH2015 between 8 and 48 h post infection (p.i.). Phenotypic analysis of microglia indicated that SPH2015 has a greater capacity for immune evasion. Transcriptome analysis of OHC at 16 h p.i. disclosed 32 and 113 differentially expressed genes (DEGs) in response to infection with PE243 and SPH2015, respectively. Functional enrichment analysis suggested that infection with SPH2015 activates mostly astrocytes rather than microglia. PE243 downregulated biological process of proliferation of brain cells and upregulated those associated with neuron death, while SPH2015 downregulated processes related to neuronal development. Both isolates downregulated cognitive and behavioral development processes. Ten genes were similarly regulated by both isolates. They are putative biomarkers of early hippocampus response to ZIKV infection. At 5, 7, and 10 days p.i., neuronal density of infected OHC remained below controls, and mature neurons of infected OHC showed an increase in the epigenetic mark H3K4me3, which is associated to a transcriptionally active state. This feature is more prominent in response to SPH2015. CONCLUSION: Subtle genetic diversity of the ZIKV affects the dynamics of viral dissemination in the hippocampus and host response in the early stages of infection, which may lead to different long-term effects in neuronal population.

Sensing of mycobacterial arabinogalactan by galectin-9 exacerbates mycobacterial infection.

Mycobacterial arabinogalactan (AG) is an essential cell wall component of mycobacteria and a frequent structural and bio-synthetical target for anti-tuberculosis (TB) drug development. Here, we report that mycobacterial AG is recognized by galectin-9 and exacerbates mycobacterial infection. Administration of AG-specific aptamers inhibits cellular infiltration caused by Mycobacterium tuberculosis (Mtb) or Mycobacterium bovis BCG, and moderately increases survival of Mtb-infected mice or Mycobacterium marinum-infected zebrafish. AG interacts with carbohydrate recognition domain (CRD) 2 of galectin-9 with high affinity, and galectin-9 associates with transforming growth factor ß-activated kinase 1 (TAK1) via CRD2 to trigger subsequent activation of extracellular signal-regulated kinase (ERK) as well as induction of the expression of matrix metalloproteinases (MMPs). Moreover, deletion of galectin-9 or inhibition of MMPs blocks AG-induced pathological impairments in the lung, and the AG-galectin-9 axis aggravates the process of Mtb infection in mice. These results demonstrate that AG is an important virulence factor of mycobacteria and galectin-9 is a novel receptor for Mtb and other mycobacteria, paving the way for the development of novel effective TB immune modulators.

Clinical presentation and neural correlates of stroke-associated spatial delusions.

BACKGROUND AND PURPOSE: Incongruent beliefs about self-localization in space markedly disturb patients' behavior. Spatial delusions, or reduplicative paramnesias, are characterized by a firm conviction of place reduplication, transformation, or mislocation. Evidence suggests they are frequent after right hemisphere lesions, but comprehensive information about their clinical features is lacking. METHODS: We prospectively screened 504 acute right-hemisphere stroke patients for the presence of spatial delusions. Their behavioral and clinical features were systematically assessed. Then, we analyzed the correlation of their duration with the magnitude of structural disruption of belief-associated functional networks. Finally, we described the syndrome subtypes and evaluated whether the clinical categorization would be predicted by the structural disruption of familiarity-associated functional networks using an unsupervised k-means clustering algorithm. RESULTS: Sixty patients with spatial delusions were identified and fully characterized. Most (93%) localized the misidentified places closer to home than the hospital. The median time duration was 3 days (interquartile range = 1-7 days), and it was moderately correlated with the magnitude of structural-functional decoupling of belief-associated functional networks (r = 0.39, p = 0.02; beta coefficient regressing for lesion volume = 3.18, p = 0.04). Each clinical subtype had characteristic response patterns, which were reported, and representative examples were provided. Clustering based on structural disruption of familiarity- and unfamiliarity-associated functional networks poorly matched the clinical categorization (lesion: Rand index = 0.47; structural disconnection: Rand index = 0.51). CONCLUSIONS: The systematic characterization of the peculiar clinical features of stroke-associated spatial delusions may improve the syndrome diagnosis and clinical approaches. The novel evidence about their neural correlates fosters the clarification of the pathophysiology of delusional misidentifications.

Spatial orientation: A relationship with inferential memory.

Two branches of the scientific literature have dominated our understanding of hippocampal function. One focuses on the support this structure offers to declarative memory, while the other views the hippocampus as a part of a system dedicated to spatial navigation. These two different visions can be reconciled in relational theory, which suggests that the hippocampus processes all kinds of associations and sequences of events. According to this, processing would be similar to a route calculation based on associations of spatial information acquired during navigation and the associative relationship established between memories without spatial content. In this paper, we present a behavioral study of healthy individuals to explore the performance of inferential memory tasks and spatial orientation tasks in a virtual environment. Inferential memory and spatial orientation task performances were positively correlated. However, after controlling for a non-inferential memory task, only the correlation between allocentric spatial orientation and inferential memory remained significant. These results provide support for the similarity between the two cognitive functions, lending credence to the relational theory of the hippocampus. Additionally, our behavioral findings are in line with the cognitive map theory, which suggests a potential association between the hippocampus and allocentric spatial representations.

Could trauma laparoscopy be the standard of care for hemodynamically stable patients? A retrospective analysis of 165 cases.

BACKGROUND: Trauma laparoscopy may provide a less invasive alternative to laparotomy by providing accurate diagnosis and minimally invasive management of selected trauma patients. The risk of missing injuries during the laparoscopic evaluation still refrains surgeons from using this approach. Our aim was to evaluate feasibility and safety of trauma laparoscopy in selected patients. METHODS: We performed a retrospective review of hemodynamically trauma patients who underwent laparoscopic management in a tertiary center in Brazil due to abdominal trauma. Patients were identified by searching through the institutional database. We collected demographic and clinical data, focusing on avoidance of exploratory laparotomy, and missed injury rate, morbidity, and length of stay. Categorical data were analyzed using Chi-square, while numerical comparisons were performed using Mann-Whitney and Kruskal-Wallis test. RESULTS: We evaluated 165 cases, of which 9.7% needed conversion to an exploratory laparotomy. One-hundred and twenty-one patients (73%) had at least one intrabdominal injury. Two missed injuries to retroperitoneal organs were identified (1.2%), of which only one was clinically relevant. Three patients died (1.8%), one of which was due to complications from an intestinal injury after conversion. No deaths were related to the laparoscopic approach. CONCLUSION: In selected hemodynamically stable trauma patients, the laparoscopic approach is feasible and safe, and reduces the need for exploratory laparotomy and its associated complications.

Shedding a light on the importance of photopatch testing: A 12-year experience in a dermatology unit.

BACKGROUND: Photopatch testing has been standardized for diagnosing photoallergic contact dermatitis but is still infrequently used. OBJECTIVES: To characterize photopatch test (PPT) results and their clinical relevance. METHODS: We collected retrospective data from patients photopatch tested in our Dermatology Unit (2010-2021), using the European PPT 'baseline' series, other allergens, and patient's own products, when appropriate. RESULTS: Out of 223 patients, 75 patients (33.6%) were reactive with 124 positive PPT reactions, considered relevant in 56/223 patients (25.1%) and in 72/124 reactions (58.1%). Most reactions were caused by topical drugs (n = 33; 45.8%), such as ketoprofen or promethazine, and 7 (9.8%) by systemic drugs, such as hydrochlorothiazide and fenofibrate. 'Classical' ultraviolet filters were responsible for six positive PPT reactions whereas there was only three relevant PPT to the 'newer' UV filters. Patients' sunscreens/cosmetics or plant extracts caused 10 positive PPT each. Additional patch test reactions were observed, mostly to Tinosorb® M. CONCLUSION: Contrary to the trend in ACD, most positive PPT reactions were caused by topical drugs, outweighing ultraviolet filters and cosmetics. We stress the low reactivity to the 'newer' UV filters included in the PPT series. PPT was occasionally positive in systemic drug photosensitivity, but overall PPT reactivity was low.

Cerebral venous thrombosis following an immunoglobulin-E mediated anaphylactic reaction.

BACKGROUND: Prothrombotic and pro-inflammatory states are known cerebral venous thrombosis risk factors. To date, two cases of venous thrombotic events after immunoglobulin-E mediated anaphylaxis have been reported. Herein, we describe the first case of cerebral venous thrombosis in close temporal relation with an immunoglobulin-E mediated anaphylactic event. CASE DESCRIPTION: A 51-year-old female presented with headache, language, and mental disturbance lasting for two days. Two days before the onset, she had undergone a provocative test with deflazacort to study an allergy history; after the test she developed a severe anaphylactic reaction. There were no other comorbidities, and in addition to contraceptive pill, she did not take other medications. On admission the patient was drowsy, with anomic aphasia, inattention and memory impairment. Magnetic Resonance Imaging depicted a left caudate and lenticulo-capsulo-thalamic venous infarct and thrombosis in the deep venous system. The patient was treated with anticoagulation and showed progressive improvement. Neoplastic and pro-thrombotic diseases were excluded. CONCLUSION: The close temporal association between the anaphylactic reaction and cerebral venous thrombosis suggests that anaphylactic reaction could have been a cerebral venous thrombosis precipitating factor. Immunoglobulin-E have been suggested to have prothrombotic activity by stimulating the release of platelet activation factor, thromboxane A2 and serotonin. This case adds on to the available information on possible cerebral venous thrombosis associated conditions.

Surface Functionalisation of Self-Assembled Quantum Dot Microlasers with a DNA Aptamer.

The surface functionalisation of self-assembled colloidal quantum dot supraparticle lasers with a thrombin binding aptamer (TBA-15) has been demonstrated. The self-assembly of CdSSe/ZnS alloyed core/shell microsphere-shape CQD supraparticles emitting at 630 nm was carried out using an oil-in-water emulsion technique, yielding microspheres with an oleic acid surface and an average diameter of 7.3 ± 5.3 µm. Surface modification of the microspheres was achieved through a ligand exchange with mercaptopropionic acid and the subsequent attachment of TBA-15 using EDC/NHS coupling, confirmed by zeta potential and Fourier transform IR spectroscopy. Lasing functionality between 627 nm and 635 nm was retained post-functionalisation, with oleic acid- and TBA-coated microspheres exhibiting laser oscillation with thresholds as low as 4.10 ± 0.37 mJ·cm-2 and 7.23 ± 0.78 mJ·cm-2, respectively.

Brazilian guidelines on diagnosis and management of traumatic vascular injuries.

Trauma is a leading cause of death, permanent disability, and health care cost worldwide. The young and economically active are the most affected population. Exsanguination due to noncompressible torso hemorrhage is one of the most frequent causes of early death, posing a significant challenge to trauma and vascular surgeons. The possibility of limb loss due to vascular injuries must also be considered. In recent decades, the approach to vascular injuries has been significantly modified. Angiotomography has become the standard method for diagnosis, endovascular techniques are currently incorporated in treatment, and damage control, such as temporary shunts, is now the preferred approach for the patients sustaining physiological derangement. Despite the importance of this topic, few papers in the Brazilian literature have offered guidelines on vascular trauma. The Brazilian Society of Angiology and Vascular Surgery has developed Projetos Diretrizes (Guideline Projects), which includes this publication on vascular trauma. Since treating trauma patients is a multidisciplinary effort, the Brazilian Trauma Society (SBAIT) was invited to participate in this project. Members of both societies reviewed the literature on vascular trauma management and together wrote these guidelines on vascular injuries of neck, thorax, abdomen, and extremities.

Yellow Fever Molecular Diagnosis Using Urine Specimens during Acute and Convalescent Phases of the Disease.

Prior studies have demonstrated prolonged presence of yellow fever virus (YFV) RNA in saliva and urine as an alternative to serum. To investigate the presence of YFV RNA in urine, we used RT-PCR for YFV screening in 60 urine samples collected from a large cohort of naturally infected yellow fever (YF) patients during acute and convalescent phases of YF infection from recent YF outbreaks in Brazil (2017 to 2018). Fifteen urine samples from acute phase infection (up to 15 days post-symptom onset) and four urine samples from convalescent phase infection (up to 69 days post-symptom onset), were YFV PCR-positive. We genotyped YFV detected in seven urine samples (five collected during the acute phase and two collected during the YF convalescent phase). Genotyping indicated the presence of YFV South American I genotype in these samples. To our knowledge, this is the first report of wild-type YFV RNA detection in the urine this far out from symptom onset (up to 69 DPS), including YFV RNA detection during the convalescent phase of YF infection. The detection of YFV RNA in urine is an indicative of YFV infection; however, the results of RT-PCR using urine as sample should be interpreted with care, since a negative result does not exclude the possibility of YFV infection. With a possible prolonged period of detection beyond the viremic phase, the use of urine samples coupled with serological tests, epidemiologic inquiry, and clinical assessment could provide a longer diagnostic window for laboratory YF diagnosis.

Unravelling the Neural Basis of Spatial Delusions After Stroke.

OBJECTIVE: Knowing explicitly where we are is an interpretation of our spatial representations. Reduplicative paramnesia is a disrupting syndrome in which patients present a firm belief of spatial mislocation. Here, we studied the largest sample of patients with delusional misidentifications of space (ie, reduplicative paramnesia) after stroke to shed light on their neurobiology. METHODS: In a prospective, cumulative, case-control study, we screened 400 patients with acute right-hemispheric stroke. We included 64 cases and 233 controls. First, lesions were delimited and normalized. Then, we computed structural and functional disconnection maps using methods of lesion-track and network-mapping. The maps were compared, controlling for confounders. Second, we built a multivariate logistic model, including clinical, behavioral, and neuroimaging data. Finally, we performed a nested cross-validation of the model with a support-vector machine analysis. RESULTS: The most frequent misidentification subtype was confabulatory mislocation (56%), followed by place reduplication (19%), and chimeric assimilation (13%). Our results indicate that structural disconnection is the strongest predictor of the syndrome and included 2 distinct streams, connecting right fronto-thalamic and right occipitotemporal structures. In the multivariate model, the independent predictors of reduplicative paramnesia were the structural disconnection map, lesion sparing of right dorsal fronto-parietal regions, age, and anosognosia. Good discrimination accuracy was demonstrated (area under the curve = 0.80 [0.75-0.85]). INTERPRETATION: Our results localize the anatomic circuits that may have a role in the abnormal spatial-emotional binding and in the defective updating of spatial representations underlying reduplicative paramnesia. This novel data may contribute to better understand the pathophysiology of delusional syndromes after stroke. ANN NEUROL 2021;89:1181-1194.

A closer look at allergic contact dermatitis caused by topical ophthalmic medications.

BACKGROUND: Allergic contact dermatitis caused by topical ophthalmic medications (OftACD) is frequently difficult to confirm with patch testing and, therefore, it is considered uncommon. METHODS: We collected retrospective data from a cohort of 65 patients with suspected OftACD patch tested in our Dermatology Unit (2005-2021) according to ESCD guidelines, using a series of topical drugs and excipients (Chemotechnique Diagnostics), including betaxolol and timolol 5% pet. kindly supplied by the pharmaceutical industry. Also, frequently used ophthalmic medications as well as patient's own products were also patch tested 'as is' in most patients. RESULTS: Positive patch tests to ophthalmic medications occurred in 44 patients (67.7%) (38F/6M; mean age 63.1 years), with 102 positive reactions. Most positive reactions were associated with active ingredients (n = 56), especially aminoglycoside antibiotics (n = 27), followed by excipients (n = 24) such as sodium metabisulfite (n = 7). There were also positive reactions to topical products tested 'as is' (n = 22), mostly containing beta-blockers, but only five of these reacted to the active ingredient. DISCUSSION: This study reinforces previous findings in OftACD, such as older age of onset, and the importance of antibiotics, contrasting with the progressively lower prevalence of excipients. In addition, it helps raising awareness for the sensitization to beta-blockers, which is probably underestimated. Patch test preparations for the diagnosis of OftACD may require protocol optimization.

Predictors of anaphylaxis to peanut and tree nuts in a Mediterranean population.

Background: Peanuts (PN) and tree nuts (TN) are major causes of anaphylaxis worldwide. We aimed to determine the clinical and demographic characteristics associated with anaphylaxis in patients sensitized to PN and/or TN in a Mediterranean population. Methods: We conducted a retrospective study, which included 198 patients allergic to PN and/or TN (allergy symptoms plus specific immunoglobulin E [sIgE] sensitization), evaluated in consultations from January 2015 to December 2020. Univariate analysis and multivariate logistic regression models were developed, including demographic, clinical, and laboratory data as independent variables, and anaphylaxis to each PN and/or TN as a dependent variables. Results: Anaphylaxis was associated with an earlier age of onset of allergy to PN, cashew and/or pistachio, and pine nut allergy but not to other TN allergies. Gender, atopic comorbidities, and cofactors were not associated with PN and/or TN anaphylaxis. Anaphylaxis to PN, cashew and/or pistachio, and pine nut were associated with reactivity to a fewer number of PN and/or TN foods. Although sIgE sensitization to lipid transfer proteins (LTP) was highly prevalent in our population, only seed storage protein (SSP) positivity was associated with anaphylaxis in PN allergy. The absence of pathogenesis-related protein family 10 sensitization correlated with PN and hazelnut anaphylaxis. A higher level of sIgE to almond extract predicted anaphylaxis but the level of sIgE to other PN and/or TN extracts did not predict it. Conclusion: The high prevalence of sensitization to the pan-allergen LTP did not seem to have a significant impact in PN and/or TN allergy severity in our study. Instead, other factors, such as early age of onset and positivity for SSPs, seem to strongly associate with anaphylaxis to specific PN and/or TN. These findings may contribute to individual risk assessment in these populations.

Osteoarticular infections in infants under 3 months of age.

BACKGROUND: Acute osteoarticular infections (OAI) in infants under 3 months of age (≤3M) are rare and remain a diagnostic challenge. Orthopedic complications and functional sequelae have been less well described in this age group. Our aims were to evaluate trends in aetiology, management, and outcomes of OAI ≤ 3M, and to compare these younger children who have OAI with older children. METHODS: A longitudinal observational study was conducted of OAI cases admitted to tertiary care pediatric hospital from 2008 to 2018. OAI ≤ 3M was compared with children above 3 months. Clinical, microbiological, imaging, and outcome data were analyzed. RESULTS: We identified 24 (9.1%) of the 263 OAI in children under 3 months. Analyzing OAI ≤ 3M there was a twofold increase since 2014; 54% were males with a median age of 28 days (IQR: 13.5-60.0), 10 (41.7%) were premature and nine (37.5%) had healthcare-associated infections. Microbiological causes were identified in 87.5%, mostly Staphylococcus aureus (57.1%) and Group B Streptococcus (23.8%), and 25% were multidrug-resistant (5 methicillin-resistant S. aureus and 1 Enterobacter cloacae). Bacteremia (100% vs 36.8%, P = 0.037), multidrug resistant bacteria (75% vs 16, P = 0.04), and healthcare-associated infections (100% vs 26.3%, P = 0.014) were associated with sequelae. Comparing OAI ≤ 3M with older children, OAI ≤ 3M were treated with longer antibiotic courses, had more complications and sequelae (17.4% vs 3.2%, P = 0.002). CONCLUSIONS: S. aureus is still the most common cause of OAI ≤ 3M, and 25% of causative bacteria were multidrug-resistant bacteria. Complications and sequelae were more frequent in OAI ≤ 3M when compared with older children.

Molecular detection of omicron SARS-CoV-2 variant is achieved by RT-LAMP despite genomic mutations.

BACKGROUND: Severe acute respiratory syndrome coronavirus (SARS-CoV-2) omicron variant was first detected in South Africa in November 2021. Since then, the number of cases due to this variant increases enormously every day in different parts of the world. Mutations within omicron genome may impair the molecular detection resulting in false negative results during Coronavirus disease 19 (COVID-19) diagnosis. OBJECTIVES: To verify if colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) targeting N and E genes would work efficiently to detect omicron SARS-CoV-2 variant and its sub-lineages. METHODS: SARS-CoV-2 reverse transcription quantitative polymerase chain reaction (RT-qPCR) positive samples were sequenced by next generation DNA sequencing. The consensus sequences generated were submitted to Pangolin tool for SARS-CoV-2 lineage identification. RT-LAMP reactions were performed at 65ºC/30 min targeting N and E. FINDINGS: SARS-CoV-2 omicron can be detected by RT-LAMP targeting N and E genes despite the genomic mutation of this more transmissible lineage. Omicron SARS-CoV-2 sub-lineages were tested and efficiently detected by RT-LAMP. We demonstrated that this test is very sensitive in detecting omicron variant, with LoD as low as 0.4 copies/µL. MAIN CONCLUSIONS: Molecular detection of omicron SARS-CoV-2 variant and its sub-lineages can be achieved by RT-LAMP despite the genomic mutations as a very sensitive surveillance tool for COVID-19 molecular diagnosis.