Peripheral nerve involvement in Churg-Strauss syndrome

Summary Peripheral neuropathy associated with bronchial asthma, multisystem organ dysfunction and idiopathic hypereosinophilia may be found in Churg-Strauss syndrome, hypereosinophilic syndrome and polyarteritis nodosa. Some authors have diagnosed their patients according to the presence in tissue biopsies of the three histological criteria of Churg and Strauss (necrotizing vasculitis, tissue eosinophilic infiltration, extravascular granulomas). We have observed three patients with a common history of a prodromal phase of allergic diseases (bronchial asthma and rhinitis) followed by a vasculitic phase with mononeuritis multiplex, purpura and arthritis, associated with hypereosinophilia of more than 1500 cells/mm³. All responded well to steroid treatment. Sural nerve biopsy revealed true vasculitis in two of these cases and a mild perivascular inflammatory infiltration in the other. On the basis of their characteristic clinical pattern, we think that our cases best fit the diagnosis of Churg-Strauss syndrome even though the typical histological features were not found in the sural nerves examined.     

Short term neurophysiological monitoring in multiple sclerosis bouts. Evaluation of steroid treatment

Visual (VEP) and brainstem auditory (BAEP) evoked potentials (EP) were recorded in 21 multiple sclerosis (MS) patients in acute relapse before and after steroid treatment. VEPs were abnormal in 14/21 patients and BAEPs in 10/21 patients before treatment. In 4 patients with acute optic neuritis (ON), an improvement of VEPs paralleled clinical evolution in 3 cases. Substantial and contrasting changes in VEPs or BAEPs, with no clinical counterpart, were related to a spontaneous fluctuation of EPs in acute relapses of MS. These changes suggest frequent subclinical (multifocal and, possibly, sequential) central nervous system involvement in MS bouts. Group analysis showed nonsignificant changes in EP parameters before and after treatment. Our results indicate that evoked potentials (EPs) are of limited value for monitoring the short-term effect of steroid treatment in MS in bouts.

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Sommario I potenziali evocati visivi (VEP) ed acustici troncoencefalici (BAEP) sono stati eseguiti in 21 pazienti affentti da sclerosi multipla (SM) in fase di poussée, prima e dopo un ciclo di trattamento con steroidi. Prima del trattamento i VEP edi BAEP sono risultati alterati in 14 e 10 pazienti rispettivamente. 4 pazienti presentavano una neurite ottica (ON) in fase acuta; in 3, dopo il trattamento, è stato rilevato un significativo miglioramento dei VEP e dell'acuità visiva. Significative, ma contrastanti, modificazioni dei VEP e BAEP, riscontrate in altri 5 pazienti, non correlate all'evoluzione clinica, sono suggestive di un interessamento subclinico, multifocale e possibilmente sequenziale, durante una poussée della SM. L'analisi per gruppi non evidenzia differenze statistiche significative tra prima e dopo il trattamento. I nostri risultati indicano che i potenziali evocati sono di limitata utilità ai fini di un monitoraggio a breve termine della SM in poussée.

     

COVID-19 in IBD: The experience of a single tertiary IBD center

BackgroundItaly has been one of the most affected countries in the world by COVID-19. There has been increasing concern regarding the impact of COVID‐19 on patients with inflammatory bowel disease (IBD), particularly in patients treated with immunosuppressants or biologics. The aim of our study is to understand the incidence of COVID-19 in a large cohort of patients with IBD. Furthermore, we analyzed possible risk factors for infection and severity of COVID-19.MethodsThis was an observational study evaluating the impact of COVID-19 on IBD patients in a single tertiary center. A 23 multiple-choice-question anonymous survey was administered to 1200 patients with IBD between March 10th and June 10th 2020.Results1158 questionnaires were analyzed. The majority of patients had Crohn's disease (CD) (60%) and most of them were in clinical remission. Among the 26 patients (2.2%) who tested positive for COVID-19, only 5 (3CD) were on biological treatment and none required hospitalization. Two patients died and were on treatment with mesalazine only. Of the 1158 patients, 521 were on biological therapy, which was discontinued in 85 (16.3%) and delayed in 195 patients (37.4%). A worsening of IBD symptoms was observed in 200 patients on biological therapy (38.4%). Most of these patients, 189 (94.5%), had stopped or delayed biological treatment, while 11 (5.5%) had continued their therapy regularly (p<0.001).ConclusionsOur data are in line with the current literature and confirm a higher incidence compared to the general population. Biological therapy for IBD seems to not be a risk factor for infection and should not be discontinued in order to avoid IBD relapse.     

A new mutation in GJC2 associated with subclinical leukodystrophy

Recessive mutations in GJC2, the gene-encoding connexin 47 (Cx47), cause Pelizaeus–Merzbacher-like disease type 1, a severe dysmyelinating disorder. One recessive mutation (p.Ile33Met) has been associated with a much milder phenotype––hereditary spastic paraplegia type 44. Here, we present evidence that a novel Arg98Leu mutation causes an even milder phenotype––a subclinical leukodystrophy. The Arg98Leu mutant forms gap junction plaques in HeLa cells comparable to wild-type Cx47, but electrical coupling was 20-fold lower in cell pairs expressing Arg98Leu than for cell pairs expressing wild-type Cx47. On the other hand, coupling between Cx47Arg98Leu and Cx43WT expressing cells did not show such reductions. Single channel conductance and normalized steady-state junctional conductance–junctional voltage (G _j–V _j) relations differed only slightly from those for wild-type Cx47. Our data suggest that the minimal phenotype in this patient results from a reduced efficiency of opening of Cx47 channels between oligodendrocyte and oligodendrocyte with preserved coupling between oligodendrocyte and astrocyte, and support a partial loss of function model for the mild Cx47 associated disease phenotypes.     

Enigmatic osteomyelitis and bilateral upper limb palsy in a neonate

This report describes a male infant who developed right upper limb palsy 5 days after birth and contralateral paralysis at 14 days. Abnormal in utero posture of the right arm had resulted in a difficult cephalic delivery. Right shoulder osteomyelitis was diagnosed at age 16 days from clinical, hematologic, and radiologic findings. Antibiotics were administered, followed by complete resolution of the symptoms in 2 weeks. Electromyographic and nerve conduction studies demonstrated direct involvement of the right brachial plexus, secondary to the osteomyelitis, explaining the unilateral onset and the persistent neurogenic pattern involving the muscles innervated by the right posterior branch to the brachial plexus. However, somatosensory evoked potentials indicated damage to the cervical spinal cord likely related to the birth trauma, which in all likelihood was the cause of the left limb palsy and contributed to the right limb picture.     

Hereditary motor and sensory neuropathy type I and type II

In an attempt to clearly identify the different HMSN subgroups, we prospectively evaluated 128 subjects (46 index cases, 39 affected and 43 unaffected relatives) on clinical, genetic and electrophysiological grounds. The diagnosis of HMNS I or II was made in 77 patients. Differential diagnosis between type I and II patients was impossible on clinical grounds alone, but nerve conduction study showed a clearcut subdivision into two populations. MCV behavior was consistent within families. Inheritance, autosomal dominant in almost all cases, was probably recessive in three HMSN I subjects and pedigree analysis pointed to X-linked transmission in one HMSN I family. We found no evidence for linkage to Duffy locus. We think that similar HMSN phenotypes can be determined by different gene defects. Ulnar nerve F-conduction velocity did not significantly differ from distal MCV in HMSN I: the evidence of a diffuse slowing of nerve conduction supports the hypothesis of a primary myelin defect.

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Sommario Allo scopo di distinguere chiaramente in sottogruppi i pazienti affetti da HMSN, abbiamo studiato prospeticamente dal punto di vista clinico, genetico ed elettrofisiologico 128 soggetti: 46 casi indice, 39 parenti affetti e 43 sani. La diagnosi di HMSN I o II è state posta in 77 casi. La distinzione tra I e II tipo è risultata impossibile dal punto di vista clinico, ma lo studio delle velocità di conduzione ha dimostrato una chiara divisione in due popolazioni. Il comportamento delle VCM è risultato omogeneo all'interno delle singole famiglie. L'ereditarietà, autosomica dominante in quasi tutti i casi, è risultata probabilmente recessiva in tre soggetti con HMSN I, mentre l'analisi dell'albero genealogico suggerisce una trasmissione X-linked in un'altra famiglia di I tipo. Non abbiamo trovato linkage con il locus Duffy. In queste neuropatie fenotipi simili possono essere determinati da differenti difetti genici. La presenza di un diffuso rallentamento della conduzione nervosa periferica, evidenziata dal confronto tra velocità di conduzione della risposta Fe VCM del nervo ulnare depone per una patogenesi primitivamente mielinica dell'HMSN I.

     

Submaximal nerve stimulation with the Datex relaxograph NMT monitor in myasthenia gravis

Recently submaximal train-of-four stimulation of motor nerves has been reported as a reliable technique for monitoring the neuromuscular function in patients awakening from anaesthesia, in order to prevent residual curarization. On the basis of the similarity between curarization and Myasthenia Gravis, we studied the neuromuscular impairment of four myasthenic patients by means of a commercially available monitor, which has been designed for routine application in the operating room. We demonstrate that the cardinal features of Myasthenia Gravis can be easily detected with this simple and painless method.

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Sommario Recentemente la stimolazione submassimale con stimoli tipo “train-of-four” dei nervi motori è stata indicata come una valida tecnica di monitoraggio della funzione neuromuscolare del paziente in risveglio dall'anestesia per individuare eventuali curarizzazioni residue. Sulla base delle somiglianze fra curarizzazione e Miastenia Gravis abbiamo studiato la compromissione neuromuscolare di quattro pazienti miasteniche mediante l'uso di un monitor attualmente in commercio per l'uso in sala operatoria. Dimostriamo che le caratteristiche principali della Miastenia Gravis possono essere facilmente individuate con questa tecnica semplice e indolore.

     

Rapid progression of late onset axonal Charcot-Marie-Tooth disease associated with a novel MPZ mutation in the extracellular domain

Myelin protein zero (MPZ) is a major component of compact myelin in peripheral nerves where it plays an essential role in myelin formation and adhesion. MPZ gene mutations are usually responsible for demyelinating neuropathies, namely Charcot-Marie-Tooth (CMT) type 1B, Déjèrine-Sottas neuropathy and congenital hypomyelinating neuropathy. Less frequently, axonal CMT (CMT2) associated with MPZ mutations has been described. We report six patients (one sporadic case and five subjects from two apparently unrelated families) with a late onset, but rapidly progressive, axonal peripheral neuropathy. In all patients, molecular analysis demonstrated a novel heterozygous missense mutation (208C>T) in MPZ exon 2, causing the Pro70Ser substitution in the extracellular domain. The diagnosis of CMT2 associated with MPZ mutations should be considered in both sporadic and familial cases of late onset, progressive polyneuropathy. The mechanism whereby compact myelin protein mutations cause axonal neuropathy remains to be elucidated.     

Unusual neurophysiological features in Cockayne's syndrome: a report of two cases as a contribution to diagnosis and classification

To clarify the diagnostic value of neurophysiological investigations in patients with Cockayne's syndrome (CS). The study involved two patients with clinical diagnoses of classical and severe CS, who were neurophysiologically evaluated by means of: (1) multimodal visual (VEPs), brainstem auditory (BAEPs) and upper limb somatosensory (SEPs) evoked potentials; (2) electroretinography; and (3) nerve conduction and needle electromyography studies. Both patients showed multimodal evoked potential (EP) signs of central nervous system involvement that overlapped in severity and extent, and were consistent with demyelination along the central sensory pathways. Flash VEPs and SEPs were more altered than pattern VEPs and BAEPs. No signs of retinopathy or hearing loss of cochlear origin were detected. The nerve conduction and needle electromyography studies showed severe signs of sensory and motor demyelinating and axonal peripheral neuropathy. Peripheral neuropathy was clinically uncertain. There were no significant differences between the two patients. Our results show that combined multimodal EP and nerve conduction studies are diagnostically highly sensitive even in the early stage of CS, but their ability to distinguish classical and severe CS is limited. The unusual features were characterised by the absence of clinical and electrophysiological signs of otherwise common retinopathy and neurosensory hearing loss. BAEPs seem to be more useful than VEPs or SEPs in the diagnostic work-up of patients with suspected CS.