Hyperbaric oxygen (HBO2) treatment is regularly used as adjuvant treatment in patients with necrotizing soft tissue infections (NSTI). Several observational studies have suggested an association between hyperbaric oxygen (HBO2) treatment and improved survival in patients with necrotizing soft tissue infections (NSTIs); however, the evidence remains inconclusive. Most patients with NSTI are severely ill, having sepsis or septic shock, and requiring mechanical ventilation and inotropic support in an intensive care unit (ICU). Although recent data suggest that the beneficial effect of HBO2 may be largest in the most severely ill, not all patients may receive it due to hemodynamic instability, pressure chamber capabilities, and availability, thereby potentially introducing selection bias. From January 2013 until June 2017, we conducted a multicenter, prospective, consecutive, observational study (The INFECT study, ClinicalTrials.gov number; NCT01790698) enrolling NSTI patients at five clinical centers delivering HBO2 to NSTI patients in an ICU setting in Denmark, Norway, and Sweden. A total of 409 consecutive patients with necrotizing soft tissue infections were prospectively enrolled in the study, of whom 402 (98.3

An exhausted antiviral immune response is observed in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-SARS-CoV-2 syndrome, also termed long COVID. In this study, potential mechanisms behind this exhaustion were investigated. First, the viral load of Epstein–Barr virus (EBV), human adenovirus (HAdV), human cytomegalovirus (HCMV), human herpesvirus 6 (HHV6), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was determined in sputum samples (n = 29) derived from ME/CFS patients (n = 13), healthy controls (n = 10), elderly healthy controls (n = 4), and immunosuppressed controls (n = 2). Secondly, autoantibodies (autoAbs) to type I interferon (IFN-I) in sputum were analyzed to possibly explain impaired viral immunity. We found that ME/CFS patients released EBV at a significantly higher level compared to controls (p = 0.0256). HHV6 was present in ~50% of all participants at the same level. HAdV was detected in two cases with immunosuppression and severe ME/CFS, respectively. HCMV and SARS-CoV-2 were found only in immunosuppressed controls. Notably, anti-IFN-I autoAbs in ME/CFS and controls did not differ, except in a severe ME/CFS case showing an increased level. We conclude that ME/CFS patients, compared to controls, have a significantly higher load of EBV. IFN-I autoAbs cannot explain IFN-I dysfunction, with the possible exception of severe cases, also reported in severe SARS-CoV-2. We forward that additional mechanisms, such as the viral evasion of IFN-I effect via the degradation of IFN-receptors, may be present in ME/CFS, which demands further studies.

Background:Chronic radiation-induced cystitis is a common and often debilitating complication of radiotherapy for pelvic cancers, affecting approximately 5-10% of patients. Symptoms such as haematuria, urinary urgency, frequency, and dysuria significantly affect quality of life. Although hyperbaric oxygen (HBO2) alleviates symptoms, evidence regarding its long-term benefits is limited. This study reports on the 5-year follow-up of the RICH-ART trial, evaluating whether the therapeutic effects of HBO2 on chronic radiation-induced cystitis are sustained over a longer follow-up period. Methods:RICH-ART is a multicentre, open-label, phase 2-3 trial, conducted at five Nordic hospitals: Sahlgrenska and Karolinska (Sweden), Haukeland (Norway), Rigshospitalet (Denmark), and Turku (Finland). Eligible patients were aged 18-80 years, had completed pelvic radiotherapy at least 6 months earlier, had chronic radiation-induced cystitis, and an Expanded Prostate Cancer Index Composite (EPIC) urology score <80. Patients were randomised to receive HBO2 (30-40 sessions, 100% oxygen, breathed at 240-250 kPa, for 80-90 min daily) or standard of care with no restrictions for other medications or interventions (control group). No masking was applied. The primary outcome-change in EPIC urinary total score from baseline to 6 months- has been previously reported. After this point, patients in the control group were offered HBO2. Here, we report the secondary outcome: long-term symptom relief in all patients who received HBO2, measured as change in EPIC urinary total score from baseline to 5 years post-HBO2. Adverse events were recorded only during the period patients received HBO2. Follow-up was terminated 6 months early, in May 2022, due to administrative constraints, primarily lack of funding. RICH-ART is registered with ClinicalTrials.gov (NCT01659723), and with EudraCT (2012-001381-15). Findings:Of 223 patients screened between May 9, 2012, and Dec 20, 2017, 87 were enrolled and randomised. One patient in the intervention group and 7 patients in the control group withdrew consent immediately after randomisation. Of the remaining 79 patients, 74 completed the first part of the study. One patient in the control group declined HBO2 and three had missing data for the first year, making 70 patients eligible for follow-up. The mean EPIC urinary total score improved 18.0 points (95% CI 14.2-21.8) from 46.6 (SD 18.4) pre-HBO2 to 64.6 (SD 24.1) at 6 months, and the improvement remained stable at 19.1 points (95% CI 13.3-24.9) at year 5. Responders (n = 48; 68.6%), defined as those with ≥9-point improvement post-HBO2, maintained a mean increase of 22.9 (95% CI 16.2-29.6; p < 0.0001) at 5 years. Non-responders (n = 22; 31.4%) showed no early benefit (43.5 [SD 15.6] to 44.6 [SD 16.6]). Nine of the 70 patients (12.8%) received additional HBO2 for recurring symptoms. Interpretation:Our findings provide evidence for the long-term effects of HBO2 in the treatment of chronic radiation-induced cystitis. Sustained symptom relief over 5 years supports its potential as a key therapeutic option for managing chronic radiation-induced adverse effects. Further studies are needed to define optimal treatment protocols, identify predictive biomarkers, and evaluate health economic impact. Funding:Region Västra Götaland, Regional Health Technology Assessment Centre at Sahlgrenska University Hospital, Lions Cancer Research Fund of Western Sweden, Sweden, and Hospital district of Southwest, Finland.

Maternal environmental exposures, including viral infections, can exert intergenerational effects on the offspring's epigenome. Herein, based on the Swedish COVID-19 during Pregnancy and Early childhood study (COPE), we explored how mild SARS-CoV-2 infection during pregnancy affected the DNA methylome of peripheral blood mononuclear cells in infants, using Illumina EPIC array. We found significant alterations in DNA methylation patterns in genes related to neurodevelopmental pathways that overlap with cellular processes hijacked by viruses for their own replication. The alterations were further confirmed in cord blood mononuclear cells. Subsequently, we determined the functional consequences of epigenetic rewiring due to maternal SARS-CoV-2 infection without fetal infection and found that fetal exposure to mediators driven by maternal infection, results in an altered responsiveness of the infant's immune cells upon subsequent cell activation in vitro. Finally, we demonstrate that these functional alterations were linked to the identified DNA methylation changes. ### Competing Interest Statement M.L. and S.S. are founders of a company, which has the ambition to develop DNAm-based biomarkers for a variety of conditions, including Post-COVID Conditions. The other authors declare no competing interests. ### Funding Statement The initiation of the COPE study was financed by the Simons Foundation Autism Research Initiative, SFARI (V.S., 863675), Jane and Dan Olsson Foundation (V.S., 2021-02), Stiftelsen Erik & Lily Philipsons minnesfond (V.S., dnr 98) and Swedish Research Council grants (H.B., 2018-00470; S.B.W., 2016-00526). This substudy of the COPE study was supported by Swedish Heart Lung Foundation (M.L., 20220034), Swedish Research Council (A.R., 4.3-2019-00201 & GD-2020-138; T.A., 2020-01111; M.L., 2021-03183 & 2022-01213); Johanna Cocozza foundation (T.A.), Swedish Cancer Society (A.R., 211832Pj01H2/Infection-Autoimmunity-B-lymphoma grant) and local Linköping University funds.  ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Swedish Ethical Review Authority (dnr 2020-02189 and amendments 2020-02848, 2020-05016, 2020-06696, and 2021-00870) gave ethical approval for this work and received national biobank approval by the Biobank Väst (dnr B2000526:970). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The datasets generated during the current study are not publicly available due to ethical dilemmas in traceability of DNA methylation data, but processed data that is pseudonymized and depleted of genetic variant information (beta matrixes with Illumina probe IDs and beta values) will be available upon request through the Federated European Genome-phenome Archive (FEGA) Sweden controlled-access repository, upon publication. Bioinformatic pipelines used to analyze the data and to generate graphs and figures will be available on the following GitHub account upon publication: (https://github.com/Lerm-Lab/COPE_epigenetics/).

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disease presenting with severe fatigue, post-exertional malaise, and cognitive disturbances-among a spectrum of symptoms-that collectively render the patient housebound or bedbound. Epigenetic studies in ME/CFS collectively confirm alterations and/or malfunctions in cellular and organismal physiology associated with immune responses, cellular metabolism, cell death and proliferation, and neuronal and endothelial cell function. The sudden onset of ME/CFS follows a major stress factor that, in approximately 70% of cases, involves viral infection, and ME/CFS symptoms overlap with those of long COVID. Viruses primarily linked to ME/CFS pathology are the symbiotic herpesviruses, which follow a bivalent latent-lytic lifecycle. The complex interaction between viruses and hosts involves strategies from both sides: immune evasion and persistence by the viruses, and immune activation and viral clearance by the host. This dynamic interaction is imperative for herpesviruses that facilitate their persistence through epigenetic regulation of their own and the host genome. In the current article, we provide an overview of the epigenetic signatures demonstrated in ME/CFS and focus on the potential strategies that latent viruses-particularly Epstein-Barr virus-may employ in long-term epigenetic reprograming in ME/CFS. Epigenetic studies could aid in elucidating relevant biological pathways impacted in ME/CFS and reflect the physiological variations among the patients that stem from environmental triggers, including exogenous viruses and/or altered viral activity.

The post-viral fatigue syndromes long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have multiple, potentially overlapping, pathological processes. These include persisting reservoirs of virus, e.g., SARS-CoV-2 in long COVID patient’s tissues, immune dysregulation with or without reactivation of underlying pathogens, such as Epstein–Barr virus (EBV) and human herpesvirus 6 (HHV6), as we recently described in ME/CFS, and possibly yet unidentified viruses. In the present study we tested saliva samples from two cohorts for IgG against human adenovirus (HAdV): patients with ME/CFS ( n = 84) and healthy controls ( n = 94), with either mild/asymptomatic SARS-CoV-2 infection or no infection. A significantly elevated anti-HAdV IgG response after SARS-CoV-2 infection was detected exclusively in the patient cohort. Longitudinal/time analysis, before and after COVID-19, in the very same individuals confirmed HAdV IgG elevation after. In plasma there was no HAdV IgG elevation. We conclude that COVID-19 triggered reactivation of dormant HAdV in the oral mucosa of chronic fatigue patients indicating an exhausted dysfunctional antiviral immune response in ME/CFS, allowing reactivation of adenovirus upon stress encounter such as COVID-19. These novel findings should be considered in clinical practice for identification of patients that may benefit from therapy that targets HAdV as well.

Post-acute COVID-19 syndrome (PACS) has been defined as symptoms persisting after clearance of a COVID-19 infection. We have previously demonstrated that alterations in DNA methylation (DNAm) status persist in individuals who recovered from a COVID-19 infection, but it is currently unknown if PACS is associated with epigenetic changes. We compared DNAm patterns in patients with PACS with those in controls and in healthy COVID-19 convalescents and found a unique DNAm signature in PACS patients. This signature unravelled modified pathways that regulate angiotensin II and muscarinic receptor signalling and protein–protein interaction networks that have bearings on vesicle formation and mitochondrial function.

Purpose It is speculated that diving might be harmful to the nervous system. The aim of this study was to determine if established markers of neuronal injury were increased in the blood after diving. Methods Thirty-two divers performed two identical dives, 48 h apart, in a water-filled hyperbaric chamber pressurized to an equivalent of 42 m of sea water for 10 min. After one of the two dives, normobaric oxygen was breathed for 30 min, with air breathed after the other. Blood samples were obtained before and at 30–45 and 120 min after diving. Concentrations of glial fibrillary acidic, neurofilament light, and tau proteins were measured using single molecule array technology. Doppler ultrasound was used to detect venous gas emboli. Results Tau was significantly increased at 30–45 min after the second dive ( p < 0.0098) and at 120 min after both dives ( p < 0.0008/ p < 0.0041). Comparison of matching samples showed that oxygen breathing after diving did not influence tau results. There was no correlation between tau concentrations and the presence of venous gas emboli. Glial fibrillary acidic protein was decreased 30–45 min after the first dive but at no other point. Neurofilament light concentrations did not change. Conclusions Tau seems to be a promising marker of dive-related neuronal stress, which is independent of the presence of venous gas emboli. Future studies could validate these results and determine if there is a quantitative relationship between dive exposure and change in tau blood concentration.

BackgroundMyalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disease considered to be triggered by viral infections in a majority of cases. Symptoms overlap largely with those of post-acute sequelae of COVID-19/long-COVID implying common pathogenetic mechanisms. SARS-CoV-2 infection is risk factor for sustained latent virus reactivation that may account for the symptoms of post-viral fatigue syndromes. The aim of this study was first to investigate whether patients with ME/CFS and healthy donors (HDs) differed in their antibody response to mild/asymptomatic SARS-CoV-2 infection. Secondly, to analyze whether COVID-19 imposes latent virus reactivation in the cohorts.MethodsAnti-SARS-CoV-2 antibodies were analyzed in plasma and saliva from non-vaccinated ME/CFS (n=95) and HDs (n=110) using soluble multiplex immunoassay. Reactivation of human herpesviruses 1-6 (HSV1, HSV2, VZV, EBV, CMV, HHV6), and human endogenous retrovirus K (HERV-K) was detected by anti-viral antibody fingerprints in saliva.ResultsAt 3-6 months after mild/asymptomatic SARS-CoV-2 infection, virus-specific antibodies in saliva were substantially induced signifying a strong reactivation of latent viruses (EBV, HHV6 and HERV-K) in both cohorts. In patients with ME/CFS, antibody responses were significantly stronger, in particular EBV-encoded nuclear antigen-1 (EBNA1) IgG were elevated in patients with ME/CFS, but not in HDs. EBV-VCA IgG was also elevated at baseline prior to SARS-infection in patients compared to HDs.ConclusionOur results denote an altered and chronically aroused anti-viral profile against latent viruses in ME/CFS. SARS-CoV-2 infection even in its mild/asymptomatic form is a potent trigger for reactivation of latent herpesviruses (EBV, HHV6) and endogenous retroviruses (HERV-K), as detected by antibody fingerprints locally in the oral mucosa (saliva samples). This has not been shown before because the antibody elevation is not detected systemically in the circulation/plasma.

A majority of SARS-CoV-2 recoverees develop only mild-to-moderate symptoms, while some remain completely asymptomatic. Although viruses, including SARS-CoV-2, may evade host immune responses by epigenetic mechanisms including DNA methylation, little is known about whether these modifications are important in defence against and healthy recovery from COVID-19 in the host. To this end, epigenome-wide DNA methylation patterns from COVID-19 convalescents were compared to uninfected controls from before and after the pandemic. Peripheral blood mononuclear cell (PBMC) DNA was extracted from uninfected controls, COVID-19 convalescents, and symptom-free individuals with SARS-CoV-2-specific T cell-responses, as well as from PBMCs stimulated in vitro with SARS-CoV-2. Subsequently, the Illumina MethylationEPIC 850K array was performed, and statistical/bioinformatic analyses comprised differential DNA methylation, pathway over-representation, and module identification analyses. Differential DNA methylation patterns distinguished COVID-19 convalescents from uninfected controls, with similar results in an experimental SARS-CoV-2 infection model. A SARS-CoV-2-induced module was identified in vivo, comprising 66 genes of which six (TP53, INS, HSPA4, SP1, ESR1, and FAS) were present in corresponding in vitro analyses. Over-representation analyses revealed involvement in Wnt, muscarinic acetylcholine receptor signalling, and gonadotropin-releasing hormone receptor pathways. Furthermore, numerous differentially methylated and network genes from both settings interacted with the SARS-CoV-2 interactome. Altered DNA methylation patterns of COVID-19 convalescents suggest recovery from mild-to-moderate SARS-CoV-2 infection leaves longstanding epigenetic traces. Both in vitro and in vivo exposure caused epigenetic modulation of pathways thataffect odour perception. Future studies should determine whether this reflects host-induced protective antiviral defense or targeted viral hijacking to evade host defence.

45 Background: Epigenetic alterations upon microbial challenge have been described as both a 46 defence strategy and a result of pathogenic manipulation. While most COVID-19 studies 47 focus on inflammatory and immune-mediated responses, little is known about epigenetic 48 modifications in response to SARS-CoV-2 infection. 49 Methods: Epigenome-wide DNA methylation patterns from COVID-19 convalescents were 50 compared to uninfected controls from before and after the pandemic. Peripheral blood 51 mononuclear cell (PBMC) DNA was extracted from uninfected controls, COVID-19 52 convalescents and symptom-free individuals with SARS-CoV-2-specific T cell-responses, as 53 well as from PBMCs stimulated in vitro with SARS-CoV-2. Subsequently, the Illumina 54 MethylationEPIC 850K array was performed, and statistical/bioinformatic analyses comprised 55 differential DNA methylation, pathway over-representation and module identification 56 analyses. 57 Results: Differential DNA methylation patterns distinguished COVID-19 convalescents from 58 uninfected controls, with similar results in an experimental SARS-CoV-2 infection model. A 59 SARS-CoV-2-induced module was identified in vivo , comprising 66 genes of which six 60 ( TP53 , INS , HSPA4 , SP1 , ESR1 and FAS ) were present in corresponding in vitro analyses. 61 Over-representation analyses revealed involvement in Wnt, muscarinic acetylcholine receptor 62 signalling and gonadotropin-releasing hormone receptor pathways. Furthermore, numerous 63 differentially methylated and network genes from both settings interacted with the SARS-64

ABSTRACTBackgroundEpigenetic alterations upon microbial challenge have been described as both a defence strategy and a result of pathogenic manipulation. While most COVID-19 studies focus on inflammatory and immune-mediated responses, little is known about epigenetic modifications in response to SARS-CoV-2 infection.MethodsEpigenome-wide DNA methylation patterns from COVID-19 convalescents were compared to uninfected controls from before and after the pandemic. Peripheral blood mononuclear cell (PBMC) DNA was extracted from uninfected controls, COVID-19 convalescents and symptom-free individuals with SARS-CoV-2-specific T cell-responses, as well as from PBMCs stimulated in vitro with SARS-CoV-2. Subsequently, the Illumina MethylationEPIC 850K array was performed, and statistical/bioinformatic analyses comprised differential DNA methylation, pathway over-representation and module identification analyses.ResultsDifferential DNA methylation patterns distinguished COVID-19 convalescents from uninfected controls, with similar results in an experimental SARS-CoV-2 infection model. A SARS-CoV-2-induced module was identified in vivo, comprising 66 genes of which six (TP53, INS, HSPA4, SP1, ESR1 and FAS) were present in corresponding in vitro analyses. Over-representation analyses revealed involvement in Wnt, muscarinic acetylcholine receptor signalling and gonadotropin-releasing hormone receptor pathways. Furthermore, numerous differentially methylated and network genes from both settings interacted with the SARS-CoV-2 interactome.ConclusionsAltered DNA methylation patterns of COVID-19 convalescents suggest recovery from mild-to-moderate SARS-CoV-2 infection leaves longstanding epigenetic traces. As in vitro SARS-CoV-2 infection corroborated in vivo exposure results, this indicates DNA methylation is involved in immune cell responses to challenge with this virus. Future studies should determine whether this reflects host-induced protective antiviral defence or targeted viral hijacking to evade host defence.

How do you wash cells? Three out of four of our colleagues use experimental procedures during everyday lab-bench work that can severely impair data interpretation depending on how cells are handled. We show here that a subpopulation (2–3%) of human leukocytes immediately induce a yet unclassified lytic cell death, concomitant with discharge of chromatin entities and cell elimination, when placed in protein-free solutions (i.e., PBS and HBSS). DNA release was not restricted to hematopoietic cells but occurred also in HEK293T cells. Albumin, fetal bovine serum, polyethylene glycol, and Pluronic F-68 supplements prevented chromatin discharge. Expelled chromatin was devoid of surrounding membranes but maintained its original nuclear shape, although ∼10 times enlarged. These structures differed from DNA appearance after osmotic or detergent-induced cell lysis. Besides sounding a cautionary note to the neutrophil extracellular trap (NET) research community, in which ∼50% of all published studies used protein-free media for NET-formation, our study also provides a rapid tool for analysis of chromatin organization.

Metabolic profiling studies have recently indicated dysfunctional mitochondria in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). This includes an impaired function of pyruvate dehydrogenase complex (PDC), possibly driven by serum factor(s), which leads to inadequate adenosine triphosphate generation and excessive lactate accumulation. A reminiscent energy blockade is likely to occur in primary biliary cholangitis (PBC), caused by anti-PDC autoantibodies, as recently proposed. PBC is associated with fatigue and post-exertional malaise, also signifying ME/CFS. We herein have investigated whether ME/CFS patients have autoreactive antibodies that could interfere with mitochondrial function. We found that only 1 of 161 examined ME/CFS patients was positive for anti-PDC, while all PBC patients (15/15) presented significant IgM, IgG, and IgA anti-PDC reactivity, as previously shown. None of fibromyalgia patients (0/14), multiple sclerosis patients (0/29), and healthy blood donors (0/44) controls showed reactivities. Anti-mitochondrial autoantibodies (inner and outer membrane) were negative in ME/CFS cohort. Anti-cardiolipin antibody levels in patients did not differ significantly from healthy blood donors. In conclusion, the impaired mitochondrial/metabolic dysfunction, observed in ME/CFS, cannot be explained by presence of circulating autoantibodies against the tested mitochondrial epitopes.

Introduction: Increased concentrations of tau protein are associated with medical conditions involving the central nervous system, such as Alzheimer's disease, traumatic brain injury and hypoxia. Diving, by way of an elevated ambient pressure, can affect the nervous system, however it is not known whether it causes a rise in tau protein levels in serum. A prospective observational pilot study was performed to investigate changes in tau protein concentrations in serum after diving and also determine their relationship, if any, to the amount of inert gas bubbling in the venous blood. Methods: Subjects were 10 navy divers performing one or two dives per day, increasing in depth, over four days. Maximum dive depths ranged from 52-90 metres' sea water (msw). Air or trimix (nitrogen/oxygen/helium) was used as the breathing gas and the oxygen partial pressure did not exceed 160 kPa. Blood samples taken before the first and after the last dives were analyzed. Divers were monitored for the presence of venous gas emboli (VGE) at 10 to 15 minute intervals for up to 120 minutes using precordial Doppler ultrasound. Results: Median tau protein before diving was 0.200 pg.mL(-1)(range 0.100 to 1.10 pg.mL(-1)) and after diving was 0.450 pg.mL(-1) (range 0.100 to 1.20 pg.mL(-1); P = 0.016). Glial fibrillary acidic protein and neurofilament light protein concentrations analyzed in the same assay did not change after diving. No correlation was found between serum tau protein concentration and the amount of VGE. Conclusion: Repeated diving to between 52-90 msw is associated with a statistically significant increase in serum tau protein concentration, which could indicate neuronal stress.

Background Late radiation cystitis is an adverse effect of cancer treatment with radiotherapy in the pelvic region. Symptoms of late radiation cystitis can be assessed with the Expanded Prostate Index Composite Score (EPIC). Previous reports indicate that hyperbaric oxygen therapy reduces symptoms from late radiation cystitis, but the evidence is predominantly based on non-randomised and retrospective studies. We aimed to assess whether hyperbaric oxygen therapy would mitigate symptoms of late radiation cystitis. Methods We did a randomised, controlled, phase 2-3 trial (RICH-ART [Radiation Induced Cystitis treated with Hyperbaric oxygen-A Randomised controlled Trial]) at five Nordic university hospitals. All patients aged 18-80 years, with pelvic radiotherapy completed at least 6 months previously, a score of less than 80 in the urinary domain of the Expanded Prostate Index Composite Score (EPIC), and referred to participating hyperbaric clinics due to symptoms of late radiation cystitis, were eligible for inclusion. Exclusion criteria were ongoing bleeding requiring blood transfusion exceeding 500 mL in the past 4 weeks, permanent urinary catheter, bladder capacity less than 100 mL, fistula in the urinary bladder, previous treatment with hyperbaric oxygen therapy for late radiation injuries, and contraindications to hyperbaric oxygen therapy. After computer-generated 1:1 randomisation with block sizes of four for each stratification group (sex, time from radiotherapy to inclusion, and previous invasive surgery in the pelvic area), patients received hyperbaric oxygen therapy (30-40 sessions, 100% oxygen, breathed at a pressure of 240-250 kPa, for 80-90 min daily) or standard care with no restrictions for other medications or interventions. No masking was applied. The primary outcome was change in patient-perceived urinary symptoms assessed with EPIC from inclusion to follow-up at visit 4 (6-8 months later), measured as absolute change in EPIC urinary total score. RICH-ART closed enrolment on Dec 31, 2017; the last follow-up data will be compiled in 2023. RICH-ART is registered with ClinicalTrials.gov, number NCT01659723, and with the European Medicines Agency, number EudraCT 2012-001381-15. Findings Of 223 patients screened between May 9, 2012, and Dec 20, 2017, 87 patients were enrolled and randomly assigned to either hyperbaric oxygen therapy (n=42) or standard care (n=45). After excluding eight patients who withdrew consent directly after randomisation (one in the hyperbaric oxygen therapy group and seven in the standard care group), 79 were included in the intention-to-treat analyses (n=41 in the hyperbaric oxygen therapy group, n=38 in the standard care group). Median time from randomisation to visit 4 was 234 days (IQR 210-262) in the hyperbaric oxygen therapy group and 217 days (195-237) in the standard care group. The difference between change in group mean of EPIC urinary total score at visit 4 was 10.1 points (95% CI 2.2-18.1; p=0.013; 17.8 points [SD 18.4] in the hyperbaric oxygen therapy group vs 7.7 points [15.5] in the standard care group). 17 (41%) of 41 patients in the hyperbaric oxygen therapy group experienced transient grade 1-2 adverse events, related to sight and hearing, during the period of hyperbaric oxygen therapy. Interpretation Our results suggest that hyperbaric oxygen therapy relieves symptoms of late radiation cystitis. We conclude that hyperbaric oxygen therapy is a safe and well tolerated treatment.

PURPOSE:Necrotising soft-tissue infections (NSTI) are characterised by necrosis, fast progression, and high rates of morbidity and mortality, but our knowledge is primarily derived from small prospective studies and retrospective studies.METHODS:We performed an international, multicentre, prospective cohort study of adults with NSTI describing patient's characteristics and associations between baseline variables and microbiological findings, amputation, and 90-day mortality.RESULTS:We included 409 patients with NSTI; 402 were admitted to the ICU. Cardiovascular disease [169 patients (41%)] and diabetes [98 (24%)] were the most common comorbidities; 122 patients (30%) had no comorbidity. Before surgery, bruising of the skin [210 patients (51%)] and pain requiring opioids [172 (42%)] were common. The sites most commonly affected were the abdomen/ano-genital area [140 patients (34%)] and lower extremities [126 (31%)]. Monomicrobial infection was seen in 179 patients (44%). NSTI of the upper or lower extremities was associated with monomicrobial group A streptococcus (GAS) infection, and NSTI located to the abdomen/ano-genital area was associated with polymicrobial infection. Septic shock [202 patients (50%)] and acute kidney injury [82 (20%)] were common. Amputation occurred in 22% of patients with NSTI of an extremity and was associated with higher lactate level. All-cause 90-day mortality was 18% (95% CI 14-22); age and higher lactate levels were associated with increased mortality and GAS aetiology with decreased mortality.CONCLUSIONS:Patients with NSTI were heterogeneous regarding co-morbidities, initial symptoms, infectious localisation, and microbiological findings. Higher age and lactate levels were associated with increased mortality, and GAS infection with decreased mortality.

Myalgic encephalomyelitis, also referred to as chronic fatigue syndrome (ME/CFS) is a debilitating disease characterized by myalgia and a sometimes severe limitation of physical activity and cognition. It is exacerbated by physical and mental activity. Its cause is unknown, but frequently starts with an infection. The eliciting infection (commonly infectious mononucleosis or an upper respiratory infection) can be more or less well diagnosed. Among the human herpesviruses (HHV-1-8), HHV-4 (Epstein-Barr virus; EBV), HHV-6 (including HHV-6A and HHV-6B), and HHV-7, have been implicated in the pathogenesis of ME/CFS. It was therefore logical to search for serological evidence of past herpesvirus infection/reactivation in several cohorts of ME/CFS patients (all diagnosed using the Canada criteria). Control samples were from Swedish blood donors. We used whole purified virus, recombinant proteins, and synthetic peptides as antigens in a suspension multiplex immunoassay (SMIA) for immunoglobulin G (IgG). The study on herpesviral peptides based on antigenicity with human sera yielded novel epitope information. Overall, IgG anti-herpes-viral reactivities of ME/CFS patients and controls did not show significant differences. However, the high precision and internally controlled format allowed us to observe minor relative differences between antibody reactivities of some herpesviral antigens in ME/CFS versus controls. ME/CFS samples reacted somewhat differently from controls with whole virus HHV-1 antigens and recombinant EBV EBNA6 and EA antigens. We conclude that ME/CFS samples had similar levels of IgG reactivity as blood donor samples with HHV-1-7 antigens. The subtle serological differences should not be over-interpreted, but they may indicate that the immune system of some ME/CFS patients interact with the ubiquitous herpesviruses in a way different from that of healthy controls.