Citations

Abstract Objectives To describe CSF‐defined neuronal intermediate filament (NIF) autoimmunity. Methods NIF‐IgG CSF‐positive patients (41, 0.03% of 118599 tested, 1996–2019) were included (serum was neither sensitive nor specific). Criteria‐based patient NIF‐IgG staining of brain and myenteric NIFs was detected by indirect immunofluorescence assay (IFA); NIF‐specificity was confirmed by cell‐based assays (CBAs, alpha internexin, neurofilament light [NF‐L]), heavy‐[NF‐H] chain). Results Sixty‐one percent of 41 patients were men, median age, 61 years (range, 21–88). Syndromes were encephalopathy predominant (23), cerebellar ataxia predominant (11), or myeloradiculoneuropathies (7). MRI abnormalities (T2 hyperintensities of brain, spinal cord white matter tracts. and peripheral nerve axons) and neurophysiologic testing (EEG, EMG, evoked potentials) co‐localized with clinical neurological phenotypes (multifocal in 29%). Thirty patients (73%) had ≥ 1 immunological perturbation: cancer (paraneoplastic), 22; systemic infection (parainfectious [including ehrlichosis, 3] or HIV), 7; checkpoint‐inhibitor cancer immunotherapy, 4; other, 5. Cancers were as follows: neuroendocrine‐lineage carcinomas, 12 (small cell, 6; Merkel cell, 5; pancreatic, 1 [11/12 had NF‐L‐IgG detected, versus 8/29 others, P = 0.0005]) and other, 11. Onset was predominantly subacute (92%) and accompanied by inflammatory CSF (75%), and immunotherapy response (77%). In contrast, CSF controls (15684 total) demonstrated NIF‐IgG negativity (100% of test validation controls), and low frequencies of autoimmune diagnoses (20% of consecutively referred clinical specimens) and neuroendocrine‐lineage carcinoma diagnosis (3.1% vs. 30% of NIF cases), P < 0.0001. Median NF‐L protein concentration was higher in 8 NF‐L‐IgG‐positive patients (median, 6718 ng/L) than 16 controls. Interpretation Neurological autoimmunity, defined by CSF‐detected NIF‐IgGs, represents a continuum of treatable axonopathies, sometimes paraneoplastic or parainfectious.

Abstract Delayed diagnosis of immune-mediated necrotizing myopathy leads to increased morbidity. Patients with the chronic course without 3-hydroxy-3-methylglutaryl-coenzyme-A reductase-IgG or signal recognition particle-IgG are often challenging to diagnose. Immunotherapy response can also be difficult to assess. We created a statistical model to assist immune-mediated necrotizing myopathy diagnosis. Electrical myotonia versus fibrillations were reviewed as biomarkers for immunotherapy treatment response. Identified were 119 immune-mediated necrotizing myopathy cases and 938 other myopathy patients. Inclusion criteria included all having electrophysiological evaluations, muscle biopsies showing inflammatory/necrotizing myopathies, comprehensively recorded neurological examinations, and creatine kinase values. Electrical myotonia was recorded in 56% (67/119) of retrospective and 67% (20/30) of our validation immune-mediated necrotizing myopathy cohorts, and significantly (P &lt; 0.001) favoured immune-mediated necrotizing myopathy over other myopathies: sporadic inclusion body myositis (odds ratio = 4.78); dermatomyositis (odds ratio = 10.61); non-specific inflammatory myopathies (odds ratio = 8.46); limb-girdle muscular dystrophies (odds ratio = 5.34) or mitochondrial myopathies (odds ratio = 14.17). Electrical myotonia occurred in immune-mediated necrotizing myopathy seropositive (3-hydroxy-3-methylglutaryl-coenzyme-A reductase-IgG 70%, 37/53; signal recognition particle-IgG 29%, 5/17) and seronegative (51%, 25/49). Multivariate regression analysis of 20 variables identified 8 (including electrical myotonia) in combination accurately predicted immune-mediated necrotizing myopathy (97.1% area-under-curve). The model was validated in a separate cohort of 30 immune-mediated necrotizing myopathy cases. Delayed diagnosis of cases with electrical myotonia occurred in 24% (16/67, mean 8 months; range 0–194). Half (8/19) had a chronic course and were seronegative, with high model prediction (&gt;86%) at the first visit. Inherited myopathies were commonly first suspected in them. Follow-up evaluation in patients with electrical myotonia on immunotherapy was available in 19 (median 21 months, range 2–124) which reduced from 36% (58/162) of muscles to 7% (8/121; P &lt; 0.001). Reduced myotonia correlated with immunotherapy response in 64% (9/14) as well as with median creatine kinase reduction of 1779 U/l (range 401–9238, P &lt; 0.001). Modelling clinical features with electrical myotonia is especially helpful in immune-mediated necrotizing myopathy diagnostic suspicion among chronic indolent and seronegative cases. Electrical myotonia favours immune-mediated necrotizing myopathy diagnosis and can serve as an adjuvant immunotherapy biomarker.

Abstract Immune checkpoint inhibitors have revolutionized the landscape of cancer treatment. Alongside their many advantages, they elicit immune-related adverse events, including myopathy, which potentially result in substantial morbidity if not recognized and treated promptly. Current knowledge of immune checkpoint inhibitor-associated myopathy is limited. We conducted a 5-year retrospective study of patients with immune checkpoint inhibitor-associated myopathy. Clinical features, survival and ancillary test findings were analysed and compared with those of immune-mediated necrotizing myopathy patients without immune checkpoint inhibitor exposure seen during the same time period. We identified 24 patients with immune checkpoint inhibitor-associated myopathy (median age 69 years; range 28–86) and 38 patients with immune-mediated necrotizing myopathy. Ocular involvement occurred in 9/24 patients with immune checkpoint inhibitor exposure, without electrodiagnostic evidence of neuromuscular transmission defect, and in none of the immune-mediated necrotizing myopathy patients (P &lt; 0.001). Myocarditis occurred in eight immune checkpoint inhibitor-associated myopathy patients and in none of the immune-mediated necrotizing myopathy patients (P &lt; 0.001). Median creatine kinase was 686 IU/l in the immune checkpoint inhibitor cohort (seven with normal creatine kinase) compared to 6456 IU/l in immune-mediated necrotizing myopathy cohort (P &lt; 0.001). Lymphopenia was observed in 18 and 7 patients with and without immune checkpoint inhibitor exposure, respectively (P &lt; 0.001). Myopathological findings were similar between patients with and without immune checkpoint inhibitor exposure, consisting of necrotic fibres with no or subtle inflammation. Necrotic fibres however arranged in clusters in 10/11 immune checkpoint inhibitor-associated myopathy patients but in none of the immune checkpoint inhibitor-naïve patients (P &lt; 0.001). Despite the lower creatine kinase levels in immune checkpoint inhibitor-exposed patients, the number of necrotic fibres was similar in both groups. Immune checkpoint inhibitor-associated myopathy patients had a higher frequency of mitochondrial abnormalities and less number of regenerating fibres than immune-mediated necrotizing myopathy patients (P &lt; 0.001). Anti-hydroxy-3-methylglutaryl-CoA reductase or signal recognition particle antibodies were absent in patients with immune checkpoint inhibitor exposure but positive in two-thirds of immune checkpoint inhibitor-naïve patients. Most patients with immune checkpoint inhibitor-associated myopathy responded favourably to immunomodulatory treatments, but four died from myopathy-related complications and one from myocarditis. Intubated patients had significantly shorter survival compared to non-intubated patients (median survival of 22 days; P = 0.004). In summary, immune checkpoint inhibitor-associated myopathy is a distinct, treatable immune-mediated myopathy with common ocular involvement, frequent lymphopenia and necrotizing histopathology, which contrary to immune-mediated necrotizing myopathy, is featured by clusters of necrotic fibres and not accompanied by anti-hydroxy-3-methylglutaryl-CoA reductase or signal recognition particle antibodies. Normal or mildly elevated creatine kinase level does not exclude the diagnosis.

Introduction: High serum concentrations of advanced glycation end-products (AGEs) in older adults and diabetics are associated with an increased risk of cognitive impairment. The aim of this pilot study was to assess the feasibility of long-term adherence to a dietary intervention designed to decrease intake and exposure to circulating AGEs among older adults with type 2 diabetes. Methods: Herein, 75 participants were randomized to either a standard of care (SOC) control arm or to an intervention arm receiving instruction on reducing dietary AGEs intake. The primary outcome was a change in serum AGEs at the end of the intervention. Secondary and exploratory outcomes included adherence to diet and its association with circulating AGEs. Cognitive function and brain imaging were also assessed but were out of the scope of this article (ClinicalTrials.gov Identifier: NCT02739971). Results: The intervention resulted in a significant change over time in several serum AGEs compared to the SOC guidelines. Very high adherence (above 80%) to the AGE-lowering diet was associated with a greater reduction in serum AGEs levels. There were no significant differences between the two arms in any other metabolic markers. Conclusions: A long-term dietary intervention to reduce circulating AGEs is feasible in older adults with type 2 diabetes, especially in those who are highly adherent to the AGE-lowering diet.

Abstract Our study aims to quantitate neuromuscular morbidity from radiotherapy in Hodgkin lymphoma including: (i) frequency and (ii) time of onsets for neurological localizations; (iii) degree of disabilities and (iv) number of clinical visits compared to cardiopulmonary Hodgkin lymphoma-radiation complications. Medical records from Mayo Health systems were retrieved; identifying neuromuscular radiation treated Hodgkin lymphoma-complications from 1 January 1994 to 31 December 2016. Of an estimated 4100 post-radiotherapy Hodgkin lymphoma patients, 4.6% (189) were identified with complications. Mean latency to physician visit for symptoms was 23.7 years (range: 1–50). Most commonly identified complications included: head drop 10% (19) with or without myopathy, myopathy 39% (73), plexopathy 29% (54), myelopathy 27% (51) and polyradiculopathy 13% (24). Other findings included benign and malignant nerve sheath tumours 5% (9), phrenic and long thoracic mononeuropathies 7% (14) and compressive spinal meningioma 2% (4). Patients frequently had multiple coexisting complications (single = 76% [144], double = 17% [33], triple = 4% [8], quadruple = 2% [4]). Cardiac 28% (53) and pulmonary 15% (29) complications were also seen in these patients. History of Hodgkin lymphoma was initially overlooked by neurologists (14.3%, 48/336 clinical notes). Hospital and outpatient visits for complications were frequent: neuromuscular 19% (77/411) versus cardiopulmonary 30% (125/411). Testing was largely exclusionary, except when imaging identified secondary malignancy. Modified Rankin score at diagnosis varied: 0–1 (55.8%), 2–3 (5.8%) and 4–5 (38.3%). Neuromuscular complications among post-radiation Hodgkin lymphoma are diverse, occurring in ∼1 of 20 having markedly delayed onsets often eluding diagnosis. Frequent care visits and major morbidity are common. Survivorship recommendations should recognize the diverse neurological complications.