Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an inflammatory neuropathy, classically characterised by a slowly progressive onset and symmetrical, sensorimotor involvement. ...However, there are many phenotypic variants, suggesting that CIDP may not be a discrete disease entity but rather a spectrum of related conditions. While the abiding theory of CIDP pathogenesis is that cell-mediated and humoral mechanisms act together in an aberrant immune response to cause damage to peripheral nerves, the relative contributions of T cell and autoantibody responses remain largely undefined. In animal models of spontaneous inflammatory neuropathy, T cell responses to defined myelin antigens are responsible. In other human inflammatory neuropathies, there is evidence of antibody responses to Schwann cell, compact myelin or nodal antigens. In this review, the roles of the cellular and humoral immune systems in the pathogenesis of CIDP will be discussed. In time, it is anticipated that delineation of clinical phenotypes and the underlying disease mechanisms might help guide diagnostic and individualised treatment strategies for CIDP.
Non‐systemic vasculitic neuropathy (NSVN) is routinely considered in the differential diagnosis of progressive axonal neuropathies, especially those with asymmetric or multifocal features. Diagnostic ...criteria for vasculitic neuropathy, classification criteria for NSVN, and therapeutic approaches to NSVN are not standardized. The aim of this guideline was to derive recommendations on the classification, diagnosis, investigation, and treatment of NSVN based on the available evidence and, where evidence was not available, expert consensus. Experts on vasculitis, vasculitic neuropathy, and methodology systematically reviewed the literature for articles addressing diagnostic issues concerning vasculitic neuropathy and NSVN as well as treatment of NSVN and the small‐to‐medium vessel primary systemic vasculitides using MEDLINE, EMBASE, and the Cochrane Library. The selected articles were analyzed and classified. The group initially reached consensus on a classification of vasculitides associated with neuropathy. Non‐diabetic radiculoplexus neuropathy was incorporated within NSVN. The consensus definition of pathologically definite vasculitic neuropathy required that vessel wall inflammation be accompanied by vascular damage. Diagnostic criteria for pathologically probable vasculitic neuropathy included five predictors of definite vasculitic neuropathy: vascular deposits of IgM, C3, or fibrinogen by direct immunofluorescence; hemosiderin deposits; asymmetric nerve fiber loss; prominent active axonal degeneration; and myofiber necrosis, regeneration, or infarcts in peroneus brevis muscle biopsy (Good Practice Points from class II/III evidence). A case definition of clinically probable vasculitic neuropathy in patients lacking biopsy proof incorporated clinical features typical of vasculitic neuropathy: sensory or sensory‐motor involvement, asymmetric/multifocal pattern, lower‐limb predominance, distal‐predominance, pain, acute relapsing course, and non‐demyelinating electrodiagnostic features (Good Practice Points from class II/III evidence). Proposed exclusionary criteria for NSVN – favoring the alternate diagnosis of systemic vasculitic neuropathy – were clinicopathologic evidence of other‐organ involvement; anti‐neutrophil cytoplasmic antibody (ANCAs); cryoglobulins; sedimentation rate ≥100 mm/h; and medical condition/drug predisposing to systemic vasculitis (Good Practice Points supported by class III evidence). Three class III studies on treatment of NSVN were identified, which were insufficient to permit a level C recommendation. Therefore, the group reviewed the literature on treatment of primary small‐to‐medium vessel systemic vasculitides prior to deriving Good Practice Points on treatment of NSVN. Principal treatment recommendations were: (1) corticosteroid (CS) monotherapy for at least 6 months is considered first‐line; (2) combination therapy should be used for rapidly progressive NSVN and patients who progress on CS monotherapy; (3) immunosuppressive options include cyclophosphamide, azathioprine, and methotrexate; (4) cyclophosphamide is indicated for severe neuropathies, generally administered in IV pulses to reduce cumulative dose and side effects; (5) in patients achieving clinical remission with combination therapy, maintenance therapy should be continued for 18–24 months with azathioprine or methotrexate; and (6) clinical trials to address all aspects of treatment are needed.
Irbesartan, a long acting selective angiotensin-1 receptor inhibitor, in Marfan syndrome might reduce aortic dilatation, which is associated with dissection and rupture. We aimed to determine the ...effects of irbesartan on the rate of aortic dilatation in children and adults with Marfan syndrome.
We did a placebo-controlled, double-blind randomised trial at 22 centres in the UK. Individuals aged 6–40 years with clinically confirmed Marfan syndrome were eligible for inclusion. Study participants were all given 75 mg open label irbesartan once daily, then randomly assigned to 150 mg of irbesartan (increased to 300 mg as tolerated) or matching placebo. Aortic diameter was measured by echocardiography at baseline and then annually. All images were analysed by a core laboratory blinded to treatment allocation. The primary endpoint was the rate of aortic root dilatation. This trial is registered with ISRCTN, number ISRCTN90011794.
Between March 14, 2012, and May 1, 2015, 192 participants were recruited and randomly assigned to irbesartan (n=104) or placebo (n=88), and all were followed for up to 5 years. Median age at recruitment was 18 years (IQR 12–28), 99 (52%) were female, mean blood pressure was 110/65 mm Hg (SDs 16 and 12), and 108 (56%) were taking β blockers. Mean baseline aortic root diameter was 34·4 mm in the irbesartan group (SD 5·8) and placebo group (5·5). The mean rate of aortic root dilatation was 0·53 mm per year (95% CI 0·39 to 0·67) in the irbesartan group compared with 0·74 mm per year (0·60 to 0·89) in the placebo group, with a difference in means of −0·22 mm per year (−0·41 to −0·02, p=0·030). The rate of change in aortic Z score was also reduced by irbesartan (difference in means −0·10 per year, 95% CI −0·19 to −0·01, p=0·035). Irbesartan was well tolerated with no observed differences in rates of serious adverse events.
Irbesartan is associated with a reduction in the rate of aortic dilatation in children and young adults with Marfan syndrome and could reduce the incidence of aortic complications.
British Heart Foundation, the UK Marfan Trust, the UK Marfan Association.
Providing a chemical control over charge transport through molecular junctions is vital to developing sensing applications at the single‐molecule scale. Quantum‐interference effects that affect the ...charge transport through molecules offer a unique chance to enhance the chemical control. Here, we investigate how interference effects can be harnessed to optimize the response of single molecule dithienoborepin (DTB) junctions to the specific coordination of a fluoride ion in solution. The single‐molecule conductance of two DTB isomers is measured using scanning tunneling microscopy break‐junction (STM‐BJ) before and after fluoride ion exposure. We find a significant change of conductance before and after the capture of a fluoride ion, the magnitude of which depends on the position of the boron atom in the molecular structure. This single‐molecule sensor exhibits switching ratios of up to four orders of magnitudes, suggesting that the boron–fluoride coordination can lead to quantum‐interference effects. This is confirmed by a quantum chemical characterization, pointing toward a cross‐conjugated path through the molecular structure as the origin of the effect.
Switching boron: Organoboron compounds have unique structures owing to the unsaturated boron atom. Single‐molecule charge transport through the organoboron dithienoborepin (DTB‐A) shows a significant conductance switch (>104) after attachment to a fluoride ion. This effect is attributed to the presence of the boron atom in the conjugation path and subsequent destructive quantum interference triggered by the fluoride ion.
The purpose was to test whether physicians can validly and reproducibly diagnose diabetic sensorimotor polyneuropathy (DSPN). Twelve physicians assessed 24 patients with diabetes mellitus (DM) on ...consecutive days (576 examinations) with physical features and voice disguised. Results were compared to gold standard 75% group diagnosis (dx) and a nerve conduction score (Σ5 NC nds). Masking of patients was achieved. Reproducibility measured by the kappa coefficient and compared to Σ5 NC nd varied considerably among physicians: median and ranges: signs 0.8 (0.32–1.0); symptoms 0.79 (0.36–1.0), and diagnoses 0.47 (0.33–0.84), both low and high scores indicating poor performance. There was substantial agreement between 75% group dx and confirmed NC abnormality (abn). As compared to Σ5 NC, individual physicians' clinical dx was excessively variable and frequently inaccurate. Study physician dx from signs and symptoms were excessively variable, often overestimating DSPN. Specific approaches to improving clinical proficiency should be tested. Muscle Nerve 42:157–164, 2010
Abstract Transthyretin amyloidosis is a fatal disorder that is characterized primarily by progressive neuropathy and cardiomyopathy. It occurs in both a mutant form (with autosomal dominant ...inheritance) and a wild-type form (with predominant cardiac involvement). This article guides clinicians as to when the disease should be suspected, describes the appropriate diagnostic evaluation for those with known or suspected amyloidosis, and reviews the interventions currently available for affected patients.
Data are lacking on the utility of real-time three-dimensional (3D) echocardiography (RT3DE) in congenital abnormalities of the atrioventricular (AV) valves. The purpose of this study was to ...determine whether transthoracic RT3DE is superior to combined transthoracic echocardiography and two-dimensional (2D) transesophageal echocardiography in determining mechanisms and sites of AV valve regurgitation in congenital heart disease.
Between January 2005 and November 2007, 48 consecutive patients were studied prior to AV valve repair (22 left AV valves and 26 tricuspid valves) using 2D transthoracic echocardiography, 2D transesophageal echocardiography, and transthoracic RT3DE. Ages ranged from 24 days to 30 years. The 2D data were reviewed by blinded observers, and the real-time 3D data by a separate observer. In all patients, surgical findings were documented by a surgical report, while in 40, video recordings were also available. Surgical findings were used as the reference standard for structural abnormalities; RT3DE was the reference standard for the site of AV valve regurgitation.
Compared with 2D echocardiography, RT3DE provided superior detail of the mural leaflet and anterior commissural abnormalities for the left AV valve. For the tricuspid valve, improved detection of leaflet abnormalities, prolapse of the anterior and posterior leaflets, and commissural pathology was observed by RT3DE. Apart from a central location, surgical saline testing correlated poorly with jet location on RT3DE.
RT3DE provides complementary information as to the mechanisms and sites of AV valve failure in congenital heart disease.
The Norwood procedure for stage 1 palliation of hypoplastic left heart syndrome is performed with either the modified Blalock-Taussig (MBTS) or the right ventricle-to-pulmonary artery (RVPA) shunt. ...In our institution, surgical practice changed from use of the MBTS to use of the RVPA shunt in 2002. We analyzed survival and mental and psychomotor outcomes of the 2 consecutive surgical eras.
Between September 1996 and July 2005, 94 neonates with hypoplastic left heart syndrome underwent the Norwood procedure. Patients were recruited as neonates and followed up prospectively. Health, mental, and psychomotor outcomes (Bayley Scales of Infant Development-II) were assessed at 2 years. The study subjects were from the Norwood-MBTS era (n=62; 1996 to 2002) or the Norwood-RVPA era (n=32; 2002 to 2005). In the MBTS era, early and 2-year mortality rates were 23% (14/62) and 52% (32/62); the mean (SD) mental and psychomotor developmental indices were 79 (18) and 67 (19). In the RVPA era, early and 2-year mortality rates were 6% (2/32) and 19% (6/32); the mean (SD) mental and psychomotor developmental indices were 85 (18) and 78 (18). The 2-year mortality rate (P=0.002) and the psychomotor developmental index (P=0.029) were improved in the more recent surgical era. On multivariable Cox regression analysis, postoperative highest serum lactate independently predicted 2-year mortality in the MBTS and RVPA eras.
Analysis of 2 consecutive surgical eras of hypoplastic left heart syndrome patients undergoing the Norwood procedure showed a significant improvement in 2-year survival and psychomotor development in the more recent era. Adverse neurodevelopmental outcome in this patient population remains a concern.
Evidence suggests that outcomes in pediatric cardiac surgery are improved by consolidating care into centers of excellence. Our objective was to determine if outcomes are equivalent in patients ...across a large regional referral base, or if patients from centers without on-site surgery are at a disadvantage. Since 1996, all pediatric cardiac surgery has been offered at one of two centers within the region assessed, with the majority being performed at Stollery Children’s Hospital. All patients who underwent a Fontan between 1996 and 2016 were included. Follow-up data including length of stay (LOS), repeat surgical interventions, and transplant-free survival were acquired for each patient. The association between post-operative outcomes and home center was assessed using Kaplan–Meier survival analysis and Cox proportional Hazards models. 320 children (median age 3.3 years, IQR 2.8–4.0) were included; 120 (37.5%) had the surgical center as their home center. Cardiac anatomy was hypoplastic left heart syndrome in 107 (33.4%) subjects. Median LOS was 11 days (IQR, 8-17), and there were 8 in-hospital deaths. There were 17 deaths and 11 transplants over the course of follow-up. Five-year transplant-free survival was 92.5%. There was no difference in hospital re-intervention, late re-intervention, or survival by referral center (all
p
> 0.05). In multivariable analysis, home center was not predictive of either LOS (
R
2
= −0.40,
p
= 0.87) or transplant-free survival (1.52, 95%CI 0.66, 3.54). In children with complex congenital heart disease, a regionalized surgical care model achieves good outcomes, which do not differ according to a patient’s home base.
In October 2007, a cluster of patients experiencing a novel polyradiculoneuropathy was identified at a pork abattoir (Plant A). Patients worked in the primary carcass processing area (warm room); the ...majority processed severed heads (head-table). An investigation was initiated to determine risk factors for illness.
Symptoms of the reported patients were unlike previously described occupational associated illnesses. A case-control study was conducted at Plant A. A case was defined as evidence of symptoms of peripheral neuropathy and compatible electrodiagnostic testing in a pork abattoir worker. Two control groups were used - randomly selected non-ill warm-room workers (n = 49), and all non-ill head-table workers (n = 56). Consenting cases and controls were interviewed and blood and throat swabs were collected. The 26 largest U.S. pork abattoirs were surveyed to identify additional cases. Fifteen cases were identified at Plant A; illness onsets occurred during May 2004-November 2007. Median age was 32 years (range, 21-55 years). Cases were more likely than warm-room controls to have ever worked at the head-table (adjusted odds ratio AOR, 6.6; 95% confidence interval CI, 1.6-26.7), removed brains or removed muscle from the backs of heads (AOR, 10.3; 95% CI, 1.5-68.5), and worked within 0-10 feet of the brain removal operation (AOR, 9.9; 95% CI, 1.2-80.0). Associations remained when comparing head-table cases and head-table controls. Workers removed brains by using compressed air that liquefied brain and generated aerosolized droplets, exposing themselves and nearby workers. Eight additional cases were identified in the only two other abattoirs using this technique. The three abattoirs that used this technique have stopped brain removal, and no new cases have been reported after 24 months of follow up. Cases compared to controls had higher median interferon-gamma (IFNgamma) levels (21.7 pg/ml; vs 14.8 pg/ml, P<0.001).
This novel polyradiculoneuropathy was associated with removing porcine brains with compressed air. An autoimmune mechanism is supported by higher levels of IFNgamma in cases than in controls consistent with other immune mediated illnesses occurring in association with neural tissue exposure. Abattoirs should not use compressed air to remove brains and should avoid procedures that aerosolize CNS tissue. This outbreak highlights the potential for respiratory or mucosal exposure to cause an immune-mediated illness in an occupational setting.
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