Laboratory biomarkers associated with COVID-19 severity and management.

The heterogeneous disease course of COVID-19 is unpredictable, ranging from mild self-limiting symptoms to cytokine storms, acute respiratory distress syndrome (ARDS), multi-organ failure and death. Identification of high-risk cases will enable appropriate intervention and escalation. This study investigates the routine laboratory tests and cytokines implicated in COVID-19 for their potential application as biomarkers of disease severity, respiratory failure and need of higher-level care. From analysis of 203 samples, CRP, IL-6, IL-10 and LDH were most strongly correlated with the WHO ordinal scale of illness severity, the fraction of inspired oxygen delivery, radiological evidence of ARDS and level of respiratory support (p ≤ 0.001). IL-6 levels of ≥3.27 pg/ml provide a sensitivity of 0.87 and specificity of 0.64 for a requirement of ventilation, and a CRP of ≥37 mg/l of 0.91 and 0.66. Reliable stratification of high-risk cases has significant implications on patient triage, resource management and potentially the initiation of novel therapies in severe patients.

Plasma cell depletion with bortezomib in the treatment of refractory N-methyl-d-aspartate (NMDA) receptor antibody encephalitis. Rational developments in neuroimmunological treatment.

BACKGROUND AND PURPOSE: The aim was to assess the therapeutic potential of bortezomib in the treatment of refractory N-methyl-d-aspartate receptor (NMDAR) antibody encephalitis and its potential in other immune-mediated, B-cell-driven neurological diseases. METHODS: Two cases of severe NMDAR antibody encephalitis, resistant to first and second line therapy with steroids, intravenous immunoglobulins, plasma exchange, cyclophosphamide and rituximab, were treated with four and five cycles of 1.3 mg/m2 bortezomib at 350 and 330 days following initial presentation. RESULTS: Both patients showed significant clinical improvement with reductions of NMDAR antibody titres following bortezomib treatment. This is the first case in the literature where the NMDAR antibody level was undetectable following treatment with bortezomib. CONCLUSION: Bortezomib's unique ability to target long-lived autoreactive plasma cells appears to be a useful adjunct to standard second line immunosuppressive therapy in treatment-refractory NMDAR antibody encephalitis. The drug's pharmacodynamics, cell targeting and mechanism of action are reviewed, and it is postulated that bortezomib may be useful in a host of B-cell-driven neuroimmunological diseases.

Regarding the past, what is the trial you have always been dreaming of in CIDP?

Chronic inflammatory demyelinating polyradiculoneuropathy is an orphan disease of poorly understood cause. While first line treatments with corticosteroids, intravenous immunoglobulin and plasma exchange have at least short-term efficacy, no trial has shown that immunosuppressants work. In our dream, we will take advantage of the recently improved EU regulations to launch a Europe wide trial which will investigate the cause of the disease. It will compare three parallel groups, the anti-B cell agent rituximab, the anti-T cell agent abatacept and usual care. The trial will not be blinded and the design will be very simple. The primary outcome measure will be improvement from baseline of the overall neuropathy limitations scale (ONLS) score by 1 or more grades at 12 weeks without increase in concomitant corticosteroids or IVIg or use of plasma exchange. There will be an option to substitute improvement in the Rasch-built overall disability scale depending on future experience with that scale as the primary outcome measure. The trial will require 3 groups of 60 participants to detect an increase from 20% in the usual care group to 30% with one of the other agents with a power of 90% and P-value of 5%. It will be larger than any trial of an immunosuppressant agent so far performed in CIDP. However, recruitment will be easier because inclusion criteria will be broad and allow randomisation of any patient in whom their neurologist wishes to introduce an immunosuppressant. Avoidance of blinding and use of simple monitoring with facetime will simplify running the trial and reduce expense. The trial will follow participants and measure outcomes at 12 months. Other outcomes will consist only of grip strength, time to walk 10 m and Euroqol, the last allowing us to estimate the cost per QALY of rituximab or abatacept. Even including central analysis of key biomarkers, the trial will only cost 3 million euros, a fraction of the cost of the usual phase III pharmaceutical company trial.

Therapeutic immunoglobulin should be dosed by clinical outcome rather than by body weight in obese patients.

There are currently no data to support the suggestion that the dose of therapeutic immunoglobulin (Ig) should be capped in obese patients for pharmacokinetic (PK), safety and economic reasons. We compared IgG trough levels, increment and efficiency in matched pairs of obese and lean patients receiving either replacement or immunomodulatory immunoglobulin therapy. Thirty-one obese patients were matched with a clinically equivalent lean patient across a range of indications, including primary antibody deficiency or autoimmune peripheral neuropathy. Comprehensive matching was carried out using ongoing research databases at two centres in which the dose of Ig was based on clinical outcome, whether infection prevention or documented clinical neurological stability. The IgG trough or steady state levels, IgG increments and Ig efficiencies at times of clinical stability were compared between the obese and lean cohorts and within the matched pairs. This study shows that, at a population level, obese patients achieved a higher trough and increment (but not efficiency) for a given weight-adjusted dose compared with the lean patients. However at an individual patient level there were significant exceptions to this correlation, and upon sub-group analysis no significant difference was found between obese and lean patients receiving replacement therapy. Across all dose regimens a high body mass index (BMI) cannot be used to predict reliably the patients in whom dose restriction is clinically appropriate.

CIDP: mimics and chameleons.

The diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is usually straightforward, but atypical presentations can represent a significant diagnostic challenge. This review highlights the clinical and electrophysiological 'red flags' that should make one consider an alternative diagnosis.

Intravenous immunoglobulin and intravenous methylprednisolone as optimal induction treatment in chronic inflammatory demyelinating polyradiculoneuropathy: protocol of an international, randomised, double-blind, placebo-controlled trial (OPTIC).

BACKGROUND: International guidelines recommend either intravenous immunoglobulin (IVIg) or corticosteroids as first-line treatment for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). IVIg treatment usually leads to rapid improvement and is generally safe, but does not seem to lead to long-term remissions. Corticosteroids act more slowly and are associated with more side effects, but may induce long-term remissions. The hypothesis of this study is that combined IVIg and corticosteroid induction treatment will lead to more frequent long-term remissions than IVIg treatment alone. METHODS: An international, randomised, double-blind, placebo-controlled trial, in adults with 'probable' or 'definite' CIDP according to the EFNS/PNS 2010 criteria. Three groups of patients are included: (1) treatment naïve, (2) known CIDP patients with a relapse after > 1 year without treatment, and (3) patients with CIDP who improved within 3 months after a single course of IVIg, who subsequently deteriorate at any interval without having received additional treatment. Patients are randomised to receive 7 courses of IVIg and 1000 mg intravenous methylprednisolone (IVMP) (in sodium chloride 0.9%) or IVIg and placebo (sodium chloride 0.9%), every 3 weeks for 18 weeks. IVIg treatment consists of a loading dose of 2 g/kg (over 3-5 days) followed by 6 courses of IVIg 1/g/kg (over 1-2 days). The primary outcome is remission at 1 year, defined as improvement in disability from baseline, sustained between week 18 and week 52 without further treatment. Secondary outcomes include changes in disability, impairment, pain, fatigue, quality of life, care use and costs and (long-term) safety. DISCUSSION: In case of superiority of the combined treatment, patients will experience the advantages of two proven efficacious treatments, namely rapid improvement due to IVIg and long-term remission due to corticosteroids. Long-term remission would reduce the need for maintenance IVIg treatment and may decrease health care costs. Additionally, we expect that the combined treatment leads to a higher proportion of patients with improvement as some patients who do not respond to IVIg will respond to corticosteroids. Risks of short and long-term additional adverse events of the combined treatment need to be assessed. TRIAL REGISTRATION: ISRCTN registry ISRCTN15893334 . Prospectively registered on 12 February 2018.

Causality in acute encephalitis: defining aetiologies.

Defining the causal relationship between a microbe and encephalitis is complex. Over 100 different infectious agents may cause encephalitis, often as one of the rarer manifestations of infection. The gold-standard techniques to detect causative infectious agents in encephalitis in life depend on the study of brain biopsy material; however, in most cases this is not possible. We present the UK perspective on aetiological case definitions for acute encephalitis and extend them to include immune-mediated causes. Expert opinion was primarily used and was supplemented by literature-based methods. Wide usage of these definitions will facilitate comparison between studies and result in a better understanding of the causes of this devastating condition. They provide a framework for regular review and updating as the knowledge base increases both clinically and through improvements in diagnostic methods. The importance of new and emerging pathogens as causes of encephalitis can be assessed against the principles laid out here.

Routine blood monitoring in maintenance immunoglobulin treatment of inflammatory neuropathy: Is it clinically relevant?

BACKGROUND: Pre-treatment screening for IgA deficiency and close monitoring of full blood count(FBC) and renal function is recommended with intravenous immunoglobulin(IVIg) therapy in neurological diseases. AIMS: To examine the frequency of biochemically defined and clinically significant episodes of treatment associated haemolysis, neutropenia, thrombocytopenia and acute kidney injury(AKI) in a cohort of patients on maintenance Immunoglobulin(Ig) therapy for inflammatory neuropathy. METHODS: A retrospective review of routine blood monitoring in patients from two UK specialist peripheral nerve centres. Accepted definitions for clinically and biochemically significant haemolysis, neutropenia, thrombocytopenia and AKI were used. RESULTS: 1919 infusion episodes in 90 patients were analysed. Age(mean(S.D)) = 58.09(14.4)years, 63% male, 72% CIDP(28% MMN), 97% IVIg(3% SCIg). Dose = 1.57(0.79)g/kg/month or 97.1(37.3)g/infusion, frequency:3.9(1.4) weeks. Relative IgA deficiency was noted in 2 individuals (prevalence:2.2%, 95%C.I.:0-5.2) who received a combined total of 38 infusions(3800 g IVIg) without adverse event. No clinically significant episodes of haemolysis, neutropenia, thrombocytopenia or AKI occurred in relation to treatment. An asymptomatic drop>10 g/L haemoglobin(Hb) occurred in 3.5%(95%CI:2.7-4.3) of treatment episodes in 38 individuals, mean reduction:17.7(7.4)g/L; lowest Hb:86 g/L. Lower pre-treatment haemoglobin correlated with risk of recurrent Ig-related drop(p:0.007). Two patients with chronic renal failure(stage 1 and 3) received 28(IV) and 104(SC) infusions respectively(6416 g) without impact on estimated glomerular filtration rate(eGFR). CONCLUSIONS: No clinically significant Ig-related episodes of haemolysis or AKI were identified in this representative cohort. This suggests that routine monitoring is not essential in long-term Ig use but should be considered when clinically indicated.

Diagnosis and treatment in inflammatory neuropathies.

The inflammatory neuropathies are a large diverse group of immune-mediated neuropathies that are amenable to treatment and may be reversible. Their accurate diagnosis is essential for informing the patient of the likely course and prognosis of the disease, informing the treating physician of the appropriate therapy and informing the scientific community of the results of well-targeted, designed and performed clinical trials. With the advent of biological therapies able to manipulate the immune response more specifically, an understanding of the pathogenesis of these conditions is increasingly important. This review presents a broad overview of the pathogenesis, diagnosis and therapy of inflammatory neuropathies, concentrating on the most commonly encountered conditions.

Diagnosis and treatment in inflammatory neuropathies.

The inflammatory neuropathies are a large diverse group of immune-mediated neuropathies that are amenable to treatment and may be reversible. Their accurate diagnosis is essential for informing the patient of the likely course and prognosis of the disease, informing the treating physician of the appropriate therapy and informing the scientific community of the results of well-targeted, designed and performed clinical trials. With the advent of biological therapies able to manipulate the immune response more specifically, an understanding of the pathogenesis of these conditions is increasingly important. This review presents a broad overview of the pathogenesis, diagnosis and therapy of inflammatory neuropathies, concentrating on the most commonly encountered conditions.

Use of intravenous immunoglobulin for the treatment of autoimmune encephalitis: audit of the NHS experience.

OBJECTIVES: The treatments of limbic and other autoimmune encephalitis include immunosuppression, symptomatic treatment, and in the case of paraneoplastic syndromes, appropriate therapy for underlying neoplasms. When immunotherapy is considered, intravenous immunoglobulin is one option for treatment, either alone or in combination with corticosteroids. To date, however, evidence for the use of intravenous immunoglobulin in this context comes from case series/expert reviews as no controlled trials have been performed. We aimed to analyse the NHS England Database of intravenous immunoglobulin usage, which was designed to log use and guide procurement, to explore usage and therapeutic effect of intravenous immunoglobulin in autoimmune encephalitis in England. DESIGN: We conducted a retrospective audit and review of the NHS England Database on intravenous immunoglobulin use. SETTING: NHS England Database of intravenous immunoglobulin use which covers secondary and tertiary care prescribing and use of intravenous immunoglobulin for all patients in hospitals in England. PARTICIPANTS: Hospital in-patients with confirmed or suspected autoimmune/limbic encephalitis between September 2010 and January 2017. RESULTS: A total of 625 patients who were 18 years of age or older were treated with intravenous immunoglobulin for autoimmune encephalitis, of whom 398 were determined as having 'highly likely' or 'definite' autoimmune/limbic encephalitis. Ninety-six percent were treated with a single course of intravenous immunoglobulin. The availability and accuracy of reporting of outcomes was very poor, with complete data only available in 27% of all cases. CONCLUSIONS: This is the first review of data from this unique national database. Whilst there was evidence for clinical improvement in many cases of patients treated with intravenous immunoglobulin, the quality of outcome data was generally inadequate. Methods to improve quality, accuracy and completeness of reporting are crucial to maximise the potential value of this resource as an auditing tool.

Treatment for IgG and IgA paraproteinaemic neuropathy.

BACKGROUND: Paraproteinaemic neuropathy refers to those neuropathies associated with a monoclonal gammopathy or paraprotein. Typically it presents with a chronic predominantly sensory, symmetrical neuropathy, similar to chronic inflammatory demyelinating polyradiculoneuropathy but with relatively more sensory involvement, both clinically and neurophysiologically. The optimal treatment for IgG and IgA monoclonal gammopathy of uncertain significance neuropathies is not known. OBJECTIVES: The objective of this review is to examine the efficacy of any treatment for IgG or IgA paraproteinaemic peripheral neuropathy. SEARCH STRATEGY: We performed searches of the Cochrane Neuromuscular Disease Group Trials register (May 2005), MEDLINE (from January 1966 to May 2005), EMBASE (from January 1980 to May 2005). We also checked bibliographies for controlled trials of treatments for IgG or IgA paraproteinaemic peripheral neuropathy. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials using any treatment for IgG or IgA paraproteinaemic peripheral neuropathy. People with IgM paraproteins were excluded. We excluded participants where the monoclonal gammopathy was considered secondary to an underlying disorder. We included participants of any age with a diagnosis of monoclonal gammopathy of uncertain significance with a paraprotein of the IgG or IgA class and a neuropathy. Included participants were not required to fulfil specific electrophysiological diagnostic criteria. DATA COLLECTION AND ANALYSIS: The full texts of potentially relevant studies were obtained and assessed and independent data extraction was performed by three authors. Additional data and clarification were received from one author. MAIN RESULTS: We identified only one randomised controlled trial with 18 participants which fulfilled the predetermined inclusion criteria. Four other trials were identified but these were not randomised controlled trials. The included trial revealed a modest short-term benefit of plasma exchange in IgG or IgA paraproteinaemic neuropathy, over a short follow-up period, when compared to sham plasma exchange. AUTHORS' CONCLUSIONS: The evidence from randomised controlled trials for the treatment of IgG or IgA paraproteinaemic neuropathy is currently inadequate. More randomised controlled trials of treatments are required. These should have adequate follow-up periods and contain larger numbers of participants, perhaps through multicentre collaboration, considering the relative infrequency of this condition. Observational or open trial data provide limited support for the use of treatments such as plasma exchange, cyclophosphamide combined with prednisolone, intravenous immunoglobulin and corticosteroids. These show potential therapeutic promise but the potential benefits must be weighed against adverse effects. Their optimal use and the long-term benefits need to be considered and validated with well-designed randomised controlled trials.

Primary sciatic nerve lymphoma: a case report and review of the literature.

A patient with primary B cell non-Hodgkin's lymphoma of the sciatic nerve is described. He presented with neuropathic symptoms in the left leg, initially diagnosed as tarsal tunnel syndrome. Magnetic resonance imaging (MRI) identified the abnormality in the sciatic nerve. A fascicular biopsy of the sciatic nerve showed a diffuse large B cell non-Hodgkin's lymphoma. The patient was treated with chemotherapy and rituximab (anti-CD20 monoclonal antibody). Four months later he was in remission, and remains so 48 months from presentation. Primary lymphoma of single peripheral nerves may be a unique subtype of extranodal lymphoma, which usually follows an aggressive course and has a variable response to current therapeutic strategies. MRI is useful, alongside electrophysiological studies, in patients with atypical peripheral nerve symptoms.

Immunotherapy for IgM anti-myelin-associated glycoprotein paraprotein-associated peripheral neuropathies.

BACKGROUND: Serum monoclonal anti-myelin associated glycoprotein antibodies may be pathogenic in some people with IgM paraprotein and demyelinating neuropathy. Immunotherapies aimed at reducing the level of these antibodies might be expected to be beneficial. OBJECTIVES: To examine the efficacy of any form of immunotherapy in reducing disability and impairment resulting from IgM anti-myelin associated glycoprotein paraprotein-associated demyelinating peripheral neuropathy. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group Register (March 2005), MEDLINE (January 1966 to March 2005) and EMBASE (January 1980 to March 2005) for controlled trials. We also checked bibliographies and contacted authors and experts in the field. SELECTION CRITERIA: We included randomised or quasi-randomised controlled trials of participants of any age treated with any type of immunotherapy for anti-myelin-associated glycoprotein antibody associated demyelinating peripheral neuropathy with monoclonal gammopathy of undetermined significance of any severity. Our primary outcome measure was change in the Neuropathy Impairment Scale or Modified Rankin Scale at six months after randomisationSecondary outcome measures were: Neuropathy Impairment Scale or the Modified Rankin Score at 12 months after randomisation; ten-metre walk time, subjective clinical scores and electrophysiological parameters at six and 12 months after randomisation; IgM paraprotein levels and anti-myelin associated glycoprotein antibody titres at six months after randomisation and adverse effects of treatments. DATA COLLECTION AND ANALYSIS: We identified eight possible trials. Of these, five randomised controlled trials were included after discussion between the authors. One author extracted and the other checked the data. No missing data could be obtained from trial authors. MAIN RESULTS: The five eligible trials (97 participants) tested intravenous immunoglobulin, interferon-alpha or plasma exchange. Only two, of intravenous immunoglobulin, had comparable interventions and outcomes but both were short-term. There were no significant benefits of the treatments used in the outcomes predefined for this review, but not all the predefined outcomes were used in every included trial. Intravenous immunoglobulin showed benefits in terms of improvement in Modified Rankin Scale at two weeks and 10-metre walk time at four weeks. Serious adverse effects of intravenous immunoglobulin are known to occur from observational studies but none were encountered in these trials. AUTHORS' CONCLUSIONS: There is inadequate reliable evidence from trials of immunotherapies in anti-myelin associated glycoprotein paraproteinaemic neuropathy to recommend any particular immunotherapy treatment. Intravenous immunoglobulin is relatively safe and may produce some short-term benefit. Large well-designed randomised trials of at least six to 12 months duration are required to assess existing or novel therapies.

Higher frequencies of HLA DQB1*05:01 and anti-glycosphingolipid antibodies in a cluster of severe Guillain-Barré syndrome.

Few regional and seasonal Guillain-Barré syndrome (GBS) clusters have been reported so far. It is unknown whether patients suffering from sporadic GBS differ from GBS clusters with respect to clinical and paraclinical parameters, HLA association and antibody response to glycosphingolipids and Campylobacter jejuni (Cj). We examined 40 consecutive patients with GBS from the greater Munich area in Germany with 14 of those admitted within a period of 3 months in fall 2010 defining a cluster of GBS. Sequencing-based HLA typing of the HLA genes DRB1, DQB1, and DPB1 was performed, and ELISA for anti-glycosphingolipid antibodies was carried out. Clinical and paraclinical findings (Cj seroreactivity, cerebrospinal fluid parameters, and electrophysiology) were obtained and analyzed. GBS cluster patients were characterized by a more severe clinical phenotype with more patients requiring mechanical ventilation and higher frequencies of autoantibodies against sulfatide, GalC and certain ganglioside epitopes (54 %) as compared to sporadic GBS cases (13 %, p = 0.017). Cj seropositivity tended to be higher within GBS cluster patients (69 %) as compared to sporadic cases (46 %, p = 0.155). We noted higher frequencies of HLA class II allele DQB1*05:01 in the cluster cohort (23 %) as compared to sporadic GBS patients (3 %, p = 0.019). Cluster of severe GBS was defined by higher frequencies of autoantibodies against glycosphingolipids. HLA class II allele DQB1*05:01 might contribute to clinical worsening in the cluster patients.

Clinical, neuropathological and radiological evidence for a rare complication of rituximab therapy.

We report a rare case of myofasciitis and meningitis with deafness caused by systemic enterovirus infection in the setting of hypogammaglobulinaemia induced by rituximab. Whilst effective and generally safe, anti- CD 20 antibody therapy is increasingly recognised to result in unusual infectious complications to be considered in a treated patient presenting with neurological symptoms. These cases may pose diagnostic difficulties and can have atypical presentations. We present this rare complication of rituximab therapy, with histopathological confirmation of myofasciitis. In the older literature, enterovirus associated myofasciitis may have erroneously been termed dermatomyositis and we review the literature to demonstrate this important nosological point.

Immunotherapy for IgM anti-Myelin-Associated Glycoprotein paraprotein-associated peripheral neuropathies.

BACKGROUND: Serum monoclonal anti-Myelin Associated Glycoprotein antibodies may be pathogenic in some patients with IgM paraprotein and demyelinating neuropathy. Immunotherapies aimed at reducing the level of these antibodies might be expected to be of benefit in the treatment of the neuropathy. Many potential therapies have been described in small trials, uncontrolled studies and case reports. OBJECTIVES: To examine the efficacy of any form of immunotherapy in reducing disability and impairment resulting from IgM anti-Myelin Associated Glycoprotein paraprotein-associated demyelinating peripheral neuropathy. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group register (August 2002) and MEDLINE (January 1966 - August 2002) and EMBASE (January 1980 - August 2002) for controlled trials, checked the bibliographies to identify other controlled trials and contacted authors and other experts in the field. SELECTION CRITERIA: Types of studies: randomised or quasi-randomised controlled trials. TYPES OF PARTICIPANTS: patients of any age with anti-Myelin Associated Glycoprotein antibody associated demyelinating peripheral neuropathy with monoclonal gammopathy of undetermined significance of any severity. Types of interventions: any type of immunotherapy. Types of outcome measures: Primary: improvement in the Neuropathy Disability Score or Modified Rankin Scale six months after randomisation Secondary: Neuropathy Disability Score and/or the Modified Rankin Score 12 months after randomisation. Ten metre walk time, subjective clinical scores and electrophysiological parameters at six and 12 months after randomisation. IgM paraprotein levels and anti-Myelin Associated Glycoprotein antibody titres six months after randomisation. Adverse effects of treatments. DATA COLLECTION AND ANALYSIS: We identified six randomised controlled trials of which five were included after discussion between the authors. One author extracted the data and the other checked them. No missing data could be obtained from authors. MAIN RESULTS: The five eligible trials used four of the many available immunotherapy treatments. Only two had comparable interventions and outcomes but these were only short-term studies. There were no significant benefits of the treatments used in the predefined outcomes. However intravenous immunoglobulin showed benefits in terms of improved Modified Rankin Scale at two weeks and 10 metre walk time at four weeks. Serious adverse effects of intravenous immunoglobulin are known to occur from observational studies but none were encountered in these trials. REVIEWER'S CONCLUSIONS: There is inadequate reliable evidence from trials of immunotherapies in anti-Myelin Associated Glycoprotein paraproteinaemic neuropathy to recommend any particular immunotherapy treatment. Intravenous immunoglobulin is relatively safe and may produce some short-term benefit. Large well designed randomised trials are required to assess the efficacy of promising new therapies.