Impact of 2021 European Academy of Neurology/Peripheral Nerve Society diagnostic criteria on diagnosis and therapy of chronic inflammatory demyelinating polyradiculoneuropathy variants.

BACKGROUND AND PURPOSE: There are different criteria for the diagnosis of different variants of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). The 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) guidelines provide specific clinical criteria for each CIDP variant even if their therapeutical impact has not been investigated. METHODS: We applied the clinical criteria for CIDP variants of the 2021 EAN/PNS guidelines to 369 patients included in the Italian CIDP database who fulfilled the 2021 EAN/PNS electrodiagnostic criteria for CIDP. RESULTS: According to the 2021 EAN/PNS clinical criteria, 245 patients achieved a clinical diagnosis of typical CIDP or CIDP variant (66%). We identified 106 patients with typical CIDP (29%), 62 distal CIDP (17%), 28 multifocal or focal CIDP (7%), four sensory CIDP (1%), 27 sensory-predominant CIDP (7%), 10 motor CIDP (3%), and eight motor-predominant CIDP (2%). Patients with multifocal, distal, and sensory CIDP had milder impairment and symptoms. Patients with multifocal CIDP had less frequently reduced conduction velocity and prolonged F-wave latency and had lower levels of cerebrospinal fluid protein. Patients with distal CIDP more frequently had reduced distal compound muscle action potentials. Patients with motor CIDP did not improve after steroid therapy, whereas those with motor-predominant CIDP did. None of the patients with sensory CIDP responded to steroids, whereas most of those with sensory-predominant CIDP did. CONCLUSIONS: The 2021 EAN/PNS criteria for CIDP allow a better characterization of CIDP variants, permitting their distinction from typical CIDP and more appropriate treatment for patients.

Unclassified clinical presentations of chronic inflammatory demyelinating polyradiculoneuropathy.

BACKGROUND: To assess the ability of the 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) clinical criteria for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) to include within their classification the whole spectrum of clinical heterogeneity of the disease and to define the clinical characteristics of the unclassifiable clinical forms. METHODS: The 2021 EAN/PNS clinical criteria for CIDP were applied to 329 patients fulfilling the electrodiagnostic (and in some cases also the supportive) criteria for the diagnosis of CIDP. Clinical characteristics were reviewed for each patient not strictly fulfilling the clinical criteria ('unclassifiable'). RESULTS: At study inclusion, 124 (37.5%) patients had an unclassifiable clinical presentation, including 110 (89%) with a typical CIDP-like clinical phenotype in whom some segments of the four limbs were unaffected by weakness ('incomplete typical CIDP'), 10 (8%) with a mild distal, symmetric, sensory or sensorimotor polyneuropathy confined to the lower limbs with cranial nerve involvement ('cranial nerve predominant CIDP') and 4 (1%) with a symmetric sensorimotor polyneuropathy limited to the proximal and distal areas of the lower limbs ('paraparetic CIDP'). Eighty-one (65%) patients maintained an unclassifiable presentation during the entire disease follow-up while 13 patients progressed to typical CIDP. Patients with the unclassifiable clinical forms compared with patients with typical CIDP had a milder form of CIDP, while there was no difference in the distribution patterns of demyelination. CONCLUSIONS: A proportion of patients with CIDP do not strictly fulfil the 2021 EAN/PNS clinical criteria for diagnosis. These unclassifiable clinical phenotypes may pose diagnostic challenges and thus deserve more attention in clinical practice and research.

Frequency and clinical correlates of anti-nerve antibodies in a large population of CIDP patients included in the Italian database.

OBJECTIVE: To investigate the frequency and clinical correlates of anti-nerve autoantibodies in an unselected series of Italian patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) METHODS: Sera from 276 CIDP patients fulfilling the EFNS/PNS criteria and included in the Italian CIDP database were examined for the presence of anti-nerve autoantibodies. Results were correlated with the clinical data collected in the database. RESULTS: Anti-neurofascin155 (NF155) antibodies were found in 9/258 (3.5%) patients, anti-contactin1 (CNTN1) antibodies in 4/258 (1.6%) patients, and anti-contactin-associated protein1 (Caspr1) in 1/197 (0.5%) patients, while none had reactivity to gliomedin or neurofascin 186. Predominance of IgG4 isotype was present in 7of the 9 examined patients. Anti-NF155 patients more frequently had ataxia, tremor, and higher CSF protein levels than antibody-negative patients. Anti-CNTN1 patients more frequently had a GBS-like onset, pain, and ataxia and had more severe motor impairment at enrollment than antibody-negative patients. They more frequently received plasmapheresis, possibly reflecting a less satisfactory response to IVIg or steroids. IgM antibodies against one or more gangliosides were found in 6.5% of the patients (17/260) and were more frequently directed against GM1 (3.9%). They were frequently associated with a progressive course, with a multifocal sensorimotor phenotype and less frequent cranial nerve involvement and ataxia. CONCLUSIONS: Anti-paranodal and anti-ganglioside antibodies are infrequent in patients with CIDP but are associated with some typical clinical association supporting the hypothesis that CIDP might be a pathogenically heterogeneous syndrome possibly explaining the different clinical presentations.

Prolonged distal motor latency of median nerve does not improve diagnostic accuracy for CIDP.

Compression of the median nerve at the carpal tunnel can give demyelinating features and result in distal motor latency (DML) prolongation fulfilling the EFNS/PNS demyelinating criteria for chronic inflammatory demyelinating polyneuropathy (CIDP). Accordingly, being carpal tunnel syndrome (CTS) common in the general population, the EFNS/PNS guidelines recommend excluding the DML of the median nerve when DML prolongation may be consistent with median neuropathy at the wrist from CTS. The main aims of this study were to verify whether the inclusion of DML of the median nerve (when consistent with CTS) could improve electrophysiological diagnostic accuracy for CIDP and if the median nerve at the carpal tunnel was more prone to demyelination. We analyzed electrophysiological data from 499 patients included consecutively into the Italian CIDP Database. According to the EFNS/PNS criteria, 352 patients had a definite, 10 a probable, and 57 a possible diagnosis of CIDP, while 80 were not fulfilling the diagnostic criteria. The inclusion of DML prolongation of median nerve did not improve significantly the diagnostic accuracy for CIDP; overall diagnostic class changed in 6 out of 499 patients (1.2%) and electrodiagnostic class of CIDP changed from not fulfilling to possible in only 2 patients (2.5% of not-fulfilling patients). In conclusion, we can infer that excluding DML prolongation of median nerve does not increase the risk of missing a diagnosis of CIDP thus corroborating the current EFNS/PNS criteria.

The neurophysiological lesson from the Italian CIDP database.

INTRODUCTION: Electrophysiological diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) may be challenging. Thus, with the aim ofproviding some practical advice in electrophysiological approach to a patient with suspected CIDP, we analyzed electrophysiological data from 499 patients enrolled inthe Italian CIDP Database. METHODS: We calculated the rate of each demyelinating feature, the rate of demyelinating features per nerve, the diagnostic rate for upper andlower limb nerves, and, using a ROC curve analysis, the diagnostic accuracy of each couple of nerves and each demyelinating feature, for every CIDP subtype.Moreover, we compared the electrophysiological data of definite and probable CIDP patients with those of possible and not-fulfilling CIDP patients, and by a logisticregression analysis, we estimated the odds ratio (OR) to make an electrophysiological diagnosis of definite or probable CIDP. RESULTS: The ulnar nerve had the highestrate of demyelinating features and, when tested bilaterally, had the highest diagnostic accuracy except for DADS in which peroneal nerves were the most informative.In possible and not-fulfilling CIDP patients, a lower number of nerves and proximal temporal dispersion (TD) measurements had been performed compared to definiteand probable CIDP patients. Importantly, OR for each tested motor nerve and each TD measurement was 1.59 and 1.33, respectively. CONCLUSION: Our findingsdemonstrated that the diagnosis of CIDP may be missed due to inadequate or incomplete electrophysiological examination or interpretation. At the same time, thesedata taken together could be useful to draw a thoughtful electrophysiological approach to patients suspected of CIDP.

Frequency of diabetes and other comorbidities in chronic inflammatory demyelinating polyradiculoneuropathy and their impact on clinical presentation and response to therapy.

OBJECTIVES: To determine the prevalence of different comorbidities in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and their impact on outcome, treatment choice and response. METHODS: Using a structured questionnaire, we collected information on comorbidities from 393 patients with CIDP fulfilling the European Federation of Neurological Societies and Peripheral Nerve Society criteria included in the Italian CIDP database. RESULTS: One or more comorbidities were reported by 294 patients (75%) and potentially influenced treatment choice in 192 (49%) leading to a less frequent use of corticosteroids. Response to treatment did not differ, however, from that in patients without comorbidities. Diabetes (14%), monoclonal gammopathy of undetermined significance (MGUS) (12%) and other immune disorders (16%) were significantly more frequent in patients with CIDP than expected in the general European population. Patients with diabetes had higher disability scores, worse quality of life and a less frequent treatment response compared with patients without diabetes. Patients with IgG-IgA or IgM MGUS had an older age at CIDP onset while patients with other immune disorders had a younger age at onset and were more frequently females. IgM MGUS was more frequent in patients with motor CIDP than in patients with typical CIDP. CONCLUSIONS: Comorbidities are frequent in patients with CIDP and in almost 50% of them have an impact on treatment choice. Diabetes, MGUS and other immune diseases are more frequent in patients with CIDP than in the general population. Only diabetes seems, however, to have an impact on disease severity and treatment response possibly reflecting in some patients a coexisting diabetic neuropathy.

Sensitivity and specificity of a commercial ELISA test for anti-MAG antibodies in patients with neuropathy.

For the diagnosis of anti-MAG polyneuropathy the commercial ELISA manufacturer currently recommends a cut-off of 1000 Bühlmann Titer Units (BTU). We analyzed sera from 80 anti-MAG neuropathy patients and 383 controls (with other neuropathies or healthy controls) to assess the ELISA sensitivity and specificity at different thresholds. A better combination of sensitivity/specificity was found at a threshold >1500 BTU than at >1000 BTU. The best value of specificity was obtained at threshold >7000 BTU. There was a diagnostic grey area between 1500 and 7000 BTU in which the clinical phenotypes as well as electrophysiological studies need to be carefully assessed particularly to differentiate CIDP and anti-MAG neuropathy.

Impact of environmental factors and physical activity on disability and quality of life in CIDP.

A few observational studies and randomized trials suggest that exercise and rehabilitation may improve activity limitation and quality of life (QoL) in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), but the impact of other modifiable factors on the severity of the disease is not well understood. Using a structured questionnaire, we collected data on lifestyle and dietary habits of the patients included in the Italian CIDP database to investigate the possible influence of modifiable lifestyle factors on disability and QoL. Questionnaire data were available for 323 patients. The effect of lifestyle and dietary exposures on impairment, disability and QoL was evaluated using logistic regression models, adjusting for age, sex, disease duration, physical activity and smoking. Physical activity was associated with lower sensory impairment by the ISS scale, less disability by the INCAT and RODS scale and a better QoL in all the domains of EURO-QoL scale with the exception of anxiety/depression. None of the other parameters had an impact on these scales. This study adds evidence to the possible role of physical activity in improving symptom severity, disability and QoL in patients with CIDP. None of the other environmental factors investigated appeared to have an impact on the severity and health perception of CIDP.

RELEVANCE OF DIAGNOSTIC INVESTIGATIONS IN CHRONIC INFLAMMATORY DEMYELINATING POLIRADICULONEUROPATHY: DATA FROM THE ITALIAN CIDP DATABASE.

Background and aims to report the clinical features and the relevance of diagnostic investigations in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We retrospectively reviewed data from patients with a clinical diagnosis of CIDP included in a national database. Among the 500 included patients with a clinical diagnosis of CIDP, 437 patients (87%) fulfilled the EFNS/PNS criteria for CIDP (definite in 407, probable in 26, possible in four). In 352 patients (86%) motor nerve conduction abnormalities consistent with demyelination were sufficient for the diagnosis of definite CIDP. In 55 patients this diagnosis required the addition of one or two (from probable or from possible CIDP, respectively) supportive tests, while in 20 cases they improved the diagnosis from possible to probable CIDP, seven patients did not change diagnosis. Considering these 85 patients, CSF studies were performed in 79 cases (93%) upgrading the certainty of diagnosis in 59% of examined patients. Sensory nerve conduction studies were performed in 85% of patients with an improvement of diagnosis in 32% of cases. Nerve biopsy and US/MRI exams resulted positive in about 40% of examined patients, but they were performed in few patients (7 patients and 16 patients, respectively). A response to therapy was present in 84% of treated patients (n = 77), contributing to support the diagnosis in 40 patients in whom the other supportive criteria were not sufficient. In most patients with CIDP the diagnosis is possible solely with motor nerve conduction studies while other investigations may help improving the diagnosis in a minority of patients. This article is protected by copyright. All rights reserved.

Atypical CIDP: diagnostic criteria, progression and treatment response. Data from the Italian CIDP Database.

OBJECTIVES: A few variants of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have been described, but their frequency and evolution to typical CIDP remain unclear. To determine the frequency and characteristics of the CIDP variants, their possible evolution to typical CIDP, and treatment response. METHODS: We applied a set of diagnostic criteria to 460 patients included in a database of Italian patients with CIDP. Clinical characteristics and treatment response were reviewed for each patient. The Kaplan-Meier curve was used to estimate the progression rate from atypical to typical CIDP. RESULTS: At the time of inclusion, 376 (82%) patients had a diagnosis of typical CIDP while 84 (18%) had atypical CIDP, including 34 (7%) with distal acquired demyelinating symmetric neuropathy (DADS), 17 (4%) with purely motor, 17 (4%) with Lewis-Sumner syndrome (LSS) and 16 (3.5%) with purely sensory CIDP. Based on retrospective review of the symptoms and signs present at onset and for at least 1 year, 180 (39%) patients had an initial diagnosis compatible with atypical CIDP that in 96 (53%) patients evolved to typical CIDP. Mean disease duration was longer in patients evolving to typical CIDP than in those not evolving (p=0.0016). Patients with DADS and LSS had a less frequent response to immunoglobulin than those with typical CIDP, while patients with purely motor and sensory CIDP had a similar treatment response. CONCLUSIONS: The proportion of patients with atypical CIDP varies during the disease course. DADS and LSS have a less frequent response to intravenous immunoglobulin compared with typical CIDP, raising the possibility of a different underlying pathogenetic mechanism.

Utility of somatosensory evoked potentials in the assessment of response to IVIG in a long-lasting case of chronic immune sensory polyradiculopathy.

BACKGROUND: Chronic immune sensory polyradiculopathy (CISP) identifies a progressive acquired peripheral dysimmune neuropathy recognized as a chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) variant. We describe a young woman with a thirteen-year history of CISP with a belated variable response to intravenous immunoglobulin (IVIG) and an almost erratic anticipation of symptoms between IVIG cycles. The association of IVIG and corticosteroids, immunosuppressants, plasmapheresis, did not lead to clinical improvement and was characterized by significant side effects. We evaluated a combined clinical and somatosensory evoked potentials (SSEPs) approach aimed to identify possible predictive parameters concerning the effect and duration of each IVIG administration. Neurologic disability was evaluated using INCAT - Overall Disability Sum Score (INCAT-ODSS). CASE PRESENTATION: A 30-year-old woman presented on 2004 for the subacute onset of asymmetric paresthesias in the lower limbs over the previous six months. The symptoms had been relapsing-remitting during the first four months, followed by a slow progression, resulting in limbs ataxia and a progressive gait disturbance requiring Canadian crutches. Motor and sensory nerve conduction studies and electromyographic evaluation were into normal limits. Median SSEPs were normal, while tibial SSEPs were characterised by the bilateral absence of both lumbar and cortical responses. Cerebrospinal fluid detected an increased protein concentration, while spinal MRI showed a pronounced thickening of the sacral nerve roots, together with a tube-shaped enlargement. These findings led to the diagnosis of CISP and the patient was treated with IVIG reaching a stable remission over the following 9 years. In early 2014, the patient began to show a variable response to treatment with erratic anticipation of sensory disturbances, and a more pronounced walking disability: corticosteroids, plasmapheresis, mycophenolate mofetil and cyclophosphamide were uneffective and burdened by relevant side effects. To better assess the response to IVIG in terms of time-effect, consistency and duration, we have combined a scheduled clinical and SSEPs evaluation during and after each IVIG cycle. CONCLUSIONS: The correlation between the neurophysiological data and the INCAT-ODSS scores has allowed the modulation of IVIG cycles with a significant reduction of the clinical fluctuations and disability. SSEPs may therefore represent an useful and recommended additional aid for the treatment schedule of this rare clinical form.

Subcutaneous immunoglobulin in CIDP and MMN: a short-term nationwide study.

This multi-center Italian prospective observational study reports the 4 months follow-up data of 87 patients affected by chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN) shifted from intravenous to subcutaneous immunoglobulin treatment. A therapeutic shift from intravenous to subcutaneous immunoglobulin was performed in 87 patients (66 CIDP; 21 MMN) affected by immune-mediated peripheral neuropathies with evidence of a sustained clinical response to intravenous immunoglobulin. Patients were evaluated by means of the Overall Neuropathy Limitation Scale, Medical Research Council Scale and Life Quality Index questionnaire, both at the time of therapeutic shift and after 4 months of subcutaneous immunoglobulin treatment. A sustained clinical efficacy was observed after the switch to subcutaneous immunoglobulin: the Overall Neuropathy Limitation Scale score improved in the group of 66 CIDP patients (P = 0.018), with only one subject reporting a worsening of 1 point, and remained stable in the group of 21 MMN patients (P = 0.841), with one subject reporting a worsening of two points. An improvement in the patient's perception of therapeutic setting was reported in both groups. This large multi-center study confirms the short-term clinical equivalence of subcutaneous versus intravenous immunoglobulin and a possible improvement in the patient's perception of therapeutic setting with the subcutaneous administration. However, further studies are required to extend the results to a longer observational period.

De-novo headache with transient vertebro-basilar symptoms: role of embryonic hypoglossal artery.

We report the case of a 56-year-old man with acute onset of de-novo stabbing, pulsating and diffuse headache with subsequent appearance (within few minutes) of posterior fossa symptoms (vomiting, postural instability, anisocoria, incoordination, dysarthria, retropulsion) lasting 9-12 h. Recurrent hypertensive crises were detected during the acute observation in the Emergency Room, even in the absence of previous history of hypertension. Once subarachnoid hemorrhage and focal lesions (vascular and non-vascular) were excluded, brain computerized tomography-angiography and digital subtraction angiography disclosed the presence of left persistent primitive hypoglossal artery with bilateral vertebral artery hypoplasia and a slight aneurysmal dilation of the anterior communicating artery. Brain magnetic resonance study performed 24 h after onset of symptoms was negative for recent ischemic lesions. The clinical features of this rare vascular condition are discussed as a possible cause of magnetic resonance (diffusion weighted imaging) negative vertebro-basilar transient ischemic attack.

Persistent trigeminal artery causing "double" neurovascular conflict.

We report the case of a 73-year-old woman who presented with right VI nerve palsy and homolateral atypical trigeminal neuralgia; standard neuroradiological investigation of orbital/retroorbital regions and intracranial arteries excluded the most commonly demonstrable underlying causes while brain magnetic resonance (T1-weighted fat suppression; T2-weighted thin-section) and magnetic resonance angiography disclosed the evidence of "double" neurovascular conflict because of persistent trigeminal artery with aneurysmal dilation. A role of this almost rare vascular condition in causing painful ophthalmoplegia is discussed.

Complications of migraine: migrainous infarction.

Migraine and cerebrovascular disorders are comorbid diseases and the overlap of their clinical symptoms has relevant diagnostic and therapeutic implications. The prototypic condition of this relationship is reproduced by a clinical event named migrainous infarction (MI), listed by the ICHD-II among the "complication of migraine." We discuss the diagnostic criteria proposed for this rare condition with regard to the epidemiological studies and the clinicopathogenetic implications. In the clinical setting therefore, "possible" cases of migrainous infarction should undergo an extended diagnostic workup to rule out symptomatic migraine due to extra/intra-cranial vascular pathology (artery dissection/malformations, venous thrombosis) and to exclude a causal role for other conditions. These include patent foramen ovale and thrombophylic status that may become critical risk factors for stroke, particularly among migraineurs, in coincidence with precipitating factors that should be more accurately considered in each single case.