A Novel ß-Globin Variant, Hb Raklev [ß 75(E19) HBB:c.227T > A (Leu→Gln)].

We present a new hemoglobin variant, Hb Raklev, characterized by the substitution of leucine with glutamine at position 75 in the ß-globin chain. This variant was discovered inadvertently during an HbA1c evaluation using high performance liquid chromatography in a symptomless 54-year-old Caucasian woman, with the same variant also identified in her 16-year-old daughter. Purification of the hemoglobin revealed possibly diminished 2,3-bisphosphoglycerate (2,3-BPG) sensitivity, which may result in heightened oxygen affinity. Notably, two variants have been previously documented at this location: the unstable Hb Atlanta and the high-affinity Hb Pasadena.

Pulmonary artery pressure as a method for assessing hydration status in an anuric hemodialysis patient - a case report.

BACKGROUND: Setting the dry weight and maintaining fluid balance is still a difficult challenge in dialysis patients. Overhydration is common and associated with increased cardiac morbidity and mortality. Pulmonary hypertension is associated with volume overload in end-stage renal dysfunction patients. Thus, monitoring pulmonary pressure by a CardioMEMS device could potentially be of guidance to physicians in the difficult task of assessing fluid overload in hemodialysis patients. CASE PRESENTATION: 61-year old male with known congestive heart failure deteriorated over 3 months' time from a state with congestive heart failure and diuresis to a state of chronic kidney disease and anuria. He began a thrice/week in-hospital hemodialysis regime. As he already had implanted a CardioMEMS device due to his heart condition, we were able to monitor invasive pulmonary artery pressure during the course of dialysis sessions. To compare, we estimated overhydration by both bioimpedance and clinical assessment. Pulmonary artery pressure correlated closely with fluid drainage during dialysis and inter-dialytic weight gain. The patient reached prescribed dry weight but remained pulmonary hypertensive by definition. During two episodes of intradialytic systemic hypotension, the patient still had pulmonary hypertension by current definition. CONCLUSION: This case report observes a close correlation between pulmonary artery pressure and fluid overload in a limited amount of observations. In this case we found pulmonary artery pressure to be more sensitive towards fluid overload than bioimpedance. The patient remained pulmonary hypertensive both as he reached prescribed dry weight and experienced intradialytic hypotensive symptoms. Monitoring pulmonary artery pressure via CardioMEMS could hold great potential as a real-time guidance for fluid balance during hemodialysis, though adjusted cut-off values for pulmonary pressure for anuric patients may be needed. Further studies are needed to confirm the findings of this case report and the applicability of pulmonary pressure in assessing optimal fluid balance.

Liraglutide treatment reduced interleukin-6 in adults with type 1 diabetes but did not improve established autonomic or polyneuropathy.

AIMS: Type 1 diabetes can be complicated with neuropathy that involves immune-mediated and inflammatory pathways. Glucagon-like peptide-1 receptor agonists such as liraglutide, have shown anti-inflammatory properties, and thus we hypothesized that long-term treatment with liraglutide induced diminished inflammation and thus improved neuronal function. METHODS: The study was a randomized, double-blinded, placebo-controlled trial of adults with type 1 diabetes and confirmed symmetrical polyneuropathy. They were randomly assigned (1:1) to receive either liraglutide or placebo. Titration was 6 weeks to 1.2-1.8 mg/d, continuing for 26 weeks. The primary endpoint was change in latency of early brain evoked potentials. Secondary endpoints were changes in proinflammatory cytokines, cortical evoked potential, autonomic function and peripheral neurophysiological testing. RESULTS: Thirty-nine patients completed the study, of whom 19 received liraglutide. In comparison to placebo, liraglutide reduced interleukin-6 (-22.6%; 95% confidence interval [CI]: -38.1, -3.2; P = .025) with concomitant numerical reductions in other proinflammatory cytokines. However neuronal function was unaltered at the central, autonomic or peripheral level. Treatment was associated with -3.38 kg (95% CI: -5.29, -1.48; P < .001] weight loss and a decrease in urine albumin/creatinine ratio (-40.2%; 95% CI: -60.6, -9.5; P = .02). CONCLUSION: Hitherto, diabetic neuropathy has no cure. Speculations can be raised whether mechanism targeted treatment, e.g. lowering the systemic level of proinflammatory cytokines may lead to prevention or treatment of the neuroinflammatory component in early stages of diabetic neuropathy. If ever successful, this would serve as an example of how fundamental mechanistic principles are translated into clinical practice similar to those applied in the cardiovascular and nephrological clinic.

Implanted Peroneal Nerve Stimulator Treatment for Drop Foot Caused by Central Nervous System Lesion: A Twelve-Month Follow-up of 21 Patients.

OBJECTIVE: Drop foot is a common impairment following stroke or other causes of central pathology. We report data on patient self-perceived performance, satisfaction with performance, walking ability, and adverse effects after surgical implantation of the ActiGait® drop foot stimulator. DESIGN: Prospective case study with a 12-month follow-up. SUBJECTS: Twenty-one participants with drop foot caused by central nervous system lesion. METHODS: The patients' self-perceived performance and satisfaction with performance were evaluated using the Canadian Occupational Performance Measure (COPM). Walking ability was assessed using a 10-m walk test and a 6-min walk. Nerve conduction of the peroneal nerve was examined in 10 patients. RESULTS: At follow-up, COPM self-percieved performance from 3.2 to 6.7 points, the median increase being 2.8 (interquartile range (IQR) 2.2-5.0), p < 0.001. Likewise, the COPM satisfaction with performance increased from 2.6 to 6.9 points, the median increase being 4.2 (IQR 2.8-5.8), p < 0.001. Walking velocity increased 0.1 m/s from a baseline measurement of 0.73 m/s (95% confidence interval (95% CI) 0.03-0.2), n = 21, p < 0.01, and walking distance increased by 33 m, from a baseline measurement of 236 m (95% CI 15-51), n = 21, p < 0.001. CONCLUSION: Stimulation of the peroneal nerve by an implantable stimulator increases self-perceived performance, satisfaction with performance, and ambulation in patients with long-lasting drop foot caused by a central nervous system lesion.

Reduced Thalamic Volume and Metabolites in Type 1 Diabetes with Polyneuropathy.

OBJECTIVE: Thalamus is essential in processing of sensory information. This study explored the associations between thalamic volume and intra-thalamic metabolites and associations to clinical and experimental characteristics of sensory function in adults with diabetic polyneuropathy. METHODS: 48 adults with type 1 diabetes and confirmed distal symmetric peripheral neuropathy (DPSN) and 28 healthy controls participated in a cross-sectional study and underwent a brain magnetic resonance imaging scan. Estimates for thalamic volume were extracted using voxel-based morphometry and intra-thalamic N-acetylaspartate/creatine (NAA/cre) levels were assessed by magnetic resonance spectroscopy. Associations between thalamic volume and clinical measures, quantitative sensory testing and neuropathic phenotype were explored. RESULTS: In diabetes, reduced gray matter volume was identified including bilateral thalamus (all p≤0.001) in comparison to healthy participants. Thalamic volume estimates were positively associated to intra-thalamic NAA/cre (r=0.4; p=0.006), however not to diabetes duration (p=0.5), severity of DSPN (p=0.7), or presence of pain (p=0.3). Individuals with the lowest thalamic volume had greatest loss of protective sensation (light touch using von Frey-like filaments, p=0.037) and highest pain tolerance to electric stimulation (tetanic stimulation, p=0.008) compared to individuals with the highest thalamic volume. CONCLUSIONS: In this cohort with type 1 diabetes and severe DSPN, thalamic atrophy was present and associated with reduced NAA/cre, indicating thalamic structural loss and dysfunction. Thalamic atrophy was associated to reduced sensory function involving large fiber neuropathy and sensation to tetanic stimulation that may reflect synaptic transmission. This may ultimately contribute to the current understanding of the pathophysiology behind the perception changes evident in DSPN.

Reduced gray matter brain volume and cortical thickness in adults with type 1 diabetes and neuropathy.

In this study we investigated brain morphology in adults with diabetic neuropathy. We aimed to characterize gray matter volume (GMV) and cortical thickness, and to explore associations between whole brain morphology and clinical characteristics. 46 adults with type 1 diabetes and distal symmetric peripheral neuropathy (DSPN) and 28 healthy controls underwent magnetic resonance imaging scans. GMV and cortical thickness were estimated using voxel-/surface-based morphometry. Associations between total GMV and clinical characteristics were explored. Adults with DSPN had reduced total GMV compared with controls (627.4 ± 4.1 mL vs. 642.5 ± 5.2 mL, P = 0.026). GMV loss was more pronounced for participants with painful neuropathy compared with controls (619.1±8.9 mL vs. 642.4±5.2 mL, P = 0.026) and for those with proliferative vs. non-proliferative retinopathy (609.9 ± 6.8 mL vs. 636.0 ± 4.7 mL, P = 0.003). Characteristics such as severity of neuropathy and decreased parietal N-acetylaspartate/creatine metabolite concentration seem to be related to GMV loss in this cohort. Regional GMV loss was confined to bilateral thalamus/putamen/caudate, occipital and precentral regions, and decreased cortical thickness was identified in frontal areas. Since the observed total GMV loss influenced with clinical characteristics, brain imaging could be useful for supplementary characterization of diabetic neuropathy. The regional brain changes could suggest that some areas are more vulnerable in this cohort.

Diabetic Neuropathy Influences Control of Spinal Mechanisms.

PURPOSE: Comprehensive evaluation of the upstream sensory processing in diabetic symmetrical polyneuropathy (DSPN) is sparse. The authors investigated the spinal nociceptive withdrawal reflex and the related elicited somatosensory evoked cortical potentials. They hypothesized that DSPN induces alterations in spinal and supraspinal sensory-motor processing compared with age- and gender-matched healthy controls. METHODS: In this study, 48 patients with type 1 diabetes and DSPN were compared with 21 healthy controls. Perception and reflex thresholds were determined and subjects received electrical stimulations on the plantar site of the foot at three stimulation intensities to evoke a nociceptive withdrawal reflex. Electromyogram and EEG were recorded for analysis. RESULTS: Patients with DSPN had higher perception (P < 0.001) and reflex (P = 0.012) thresholds. Fewer patients completed the recording session compared with healthy controls (34/48 vs. 21/21; P = 0.004). Diabetic symmetrical polyneuropathy reduced the odds ratio of a successful elicited nociceptive withdrawal reflex (odds ratio = 0.045; P = 0.014). Diabetic symmetrical polyneuropathy changed the evoked potentials (F = 2.86; P = 0.025), and post hoc test revealed reduction of amplitude (-3.72 mV; P = 0.021) and prolonged latencies (15.1 ms; P = 0.013) of the N1 peak. CONCLUSIONS: The study revealed that patients with type 1 diabetes and DSPN have significantly changed spinal and supraspinal processing of the somatosensory input. This implies that DSPN induces widespread differences in the central nervous system processing of afferent A-δ and A-ß fiber input. These differences in processing may potentially lead to identification of subgroups with different stages of small fiber neuropathy and ultimately differentiated treatments.

Peripheral, synaptic and central neuronal transmission is affected in type 1 diabetes.

AIMS: We hypothesized that adults with type 1 diabetes and severe polyneuropathy have alterations in neuronal transmission at different anatomical levels. The aims were to investigate upstream sensory neuronal activation in terms of peripheral, spinal, precortical, and cortical transmission. METHODS: 48 participants with type-1 diabetes and polyneuropathy, and 21 age-matched healthy participants were included. Electrophysiological median nerve recordings were used to analyze peripheral transmission at Erb's point (P9-N11); spinal evoked potentials at Cv7 (P11-N14); subcortical evoked potentials at Oz (N14-P18); early cortical evoked potentials at CP5 (N20-P22); late cortical evoked potentials at C1 (N60-P80) and estimated cortical inter-peak latencies as measures of central conduction time. RESULTS: In comparison to healthy, the presence of diabetes prolonged peripheral transmission at P9 and N11 (+0.49 ms, p = .000; +0.47 ms, p = .04, respectively), early cortical evoked potentials at CP5: N20 (+2.41 ms, p = .003) and P22 (+5.88 ms, p = .001) and cortical potentials at C1: N60 (+39.08 ms, p = .001) and P80 (+54.55 ms, p = .000) and central conduction time. Decreased amplitudes were shown peripherally (-2.13 µV, p = .000), spinally (-0.57 µV, p = .005) and pre-cortically (-0.22 µV, p = .004). In both healthy and people with diabetes increased central conduction time were associated with decreased parasympathetic tone (ρ = -0.52, p = .027; ρ = -0.35, p = .047, respectively). CONCLUSION: Neuronal afferent transmission and brain responses were significantly impaired in diabetes and the presence of prolonged central conduction time is indicative of severe extensive neuronal damage. Trial registry number: EUDRA CT: 2013-004375-12; clinicaltrials.gov: NCT02138045.

Brain spectroscopy reveals that N-acetylaspartate is associated to peripheral sensorimotor neuropathy in type 1 diabetes.

AIMS: Emerging evidence shows, that distal symmetric peripheral neuropathy (DSPN) also involves alterations in the central nervous system. Hence, the aims were to investigate brain metabolites in white matter of adults with diabetes and DSPN, and to compare any cerebral disparities with peripheral nerve characteristics. METHODS: In type 1 diabetes, brain metabolites of 47 adults with confirmed DSPN were compared with 28 matched healthy controls using proton magnetic resonance spectroscopy (H-MRS) in the parietal region including the sensorimotor fiber tracts. RESULTS: Adults with diabetes had 9.3% lower ratio of N-acetylaspartate/creatine (NAA/cre) in comparison to healthy (p < 0.001). Lower NAA/cre was associated with lower sural (p = 0.01) and tibial (p = 0.04) nerve amplitudes, longer diabetes duration (p = 0.03) and higher age (p = 0.03). In addition, NAA/cre was significantly lower in the subgroup with proliferative retinopathy as compared to the subgroup with non-proliferative retinopathy (p = 0.02). CONCLUSIONS: The association to peripheral nerve dysfunction, indicates concomitant presence of DSPN and central neuropathies, supporting the increasing recognition of diabetic neuropathy being, at least partly, a disease leading to polyneuropathy. Decreased NAA, is a potential promising biomarker of central neuronal dysfunction or loss, and thus may be useful to measure progression of neuropathy in diabetes or other neurodegenerative diseases.

[Ulnar neuropathy in a poultry worker]. / Ulnarisneuropati hos fjerkraeslagteriarbejder.

Three months after he was employed as a poultry worker, a 48-year-old man developed involuntary jerks of his right first, fourth, and fifth fingers, paraesthesiae, weakness, and eventually wasting of the first dorsal interosseous muscle. His job entailed repetitive lifting of boxes weighing 10-25 kg with flexion of the elbow, pronation of the forearm, and ulnar deviation of the wrist. A nerve conduction study indicated ulnar neuropathy just distal to the elbow. Surgery at this level alleviated the symptoms, but shortly after his return to work, he changed jobs because of aggravation.