099 High relapse rate with steroid monotherapy in non-systemic vasculitic neuropathy

Introduction

Historically, single tissue vasculitis has been managed with steroid monotherapy. Recent data from large longitudinal databases on systemic vasculitis suggest Non-Systemic Vasculitic Neuropathy (NSVN) has higher rates of relapse, recommending that more aggressive immunotherapy is employed.

Aim

To investigate the relapse rate in NSVN in response to steroid monotherapy.

Methods

A retrospective case note review of clinically and/or pathologically defined cases of (Systemic Vasculitic Neuropathy) SVN and NSVN in two London specialist peripheral nerve centres, between 2005

- 2012 and 2015 - 2019.

Results

32 cases of SVN and 34 cases of NSVN were identified. In each group 14 individuals were treated first-line with steroid monotherapy, and 8 with cyclophosphamide. 8 SVN and 9 NSVN cases received steroids plus azathioprine. 15/32 SVN and 13/34 NSVN relapsed after first-line therapy (10/14 and 9/14 on steroid monotherapy, 3/8 and 3/9 on steroids and azathioprine, 2/8 and 1/8 on cyclophosphamide). 10 individuals stabilised with the addition of azathioprine, 13 with cyclophosphamide and 4 with Rituximab.

Conclusion

This representative case series suggests that steroid monotherapy is inadequate in the treatment of NSVN and supports an approach akin to that recommended in SVN, even if nerve is the only tissue clinically involved.

e.bunting@nhs.net

An approach to assessing immunoglobulin dependence in chronic inflammatory demyelinating inflammatory polyneuropathy

Regular immunoglobulin treatment maintains strength and prevents disability in chronic inflammatory demyelinating polyneuropathy (CIDP). Discrimination between active disease, with optimum symptom control on treatment, and disease in remission not requiring treatment is essential for therapeutic decision-making and clinical trial design. To compare treatment cessation versus gradual dose reduction in assessment of disease activity (immunoglobulin dependence) in a cohort of stable CIDP patients on maintenance immunoglobulin treatment. An approach to restabilization of immunoglobulin-dependent individuals is also described. Retrospective review of IVIg cessation or gradual reduction in 33 patients with stable CIDP on maintenance IVIg. Demographic, clinical and treatment data were collected; clinical monitoring data were recorded prospectively as part of routine clinical practice. A total of 21/33 patients (62.6%) were immunoglobulin dependent, (gradual dose reduction:11, cessation:10). Mean change in Inflammatory Rasch-built Overall Disability Scale (I-RODS) (-15, standard deviation [SD] 16) and Medical Research Council Sum Score (MRC-SS) (-4, SD: 4) was clinically and statistically meaningful (>75% exceeded minimum clinically important differences). Mean time to deterioration was 5.0 (SD: 4.6) months, shorter in cessation group (3.5 months) than gradual reduction group (8.8 months). All patients were restabilized to previous baseline (M: 2.3, SD: 4.3 months), half within 1 week of retreatment. A total of 12 patients (37.4%) remained stable without treatment for ≥2 years (remission). A total of 50% were identified rapidly by cessation and 50% by gradual dose reduction requiring mean 4.8 (SD: 2.8) years follow-up and costing £113 623 per person Ig spend. No predictors of disease activity were identified. A treatment cessation trial with close clinical monitoring is an efficient, cost-effective and safe approach to assessing disease activity in CIDP.

WED 241 Clinical relevance of regular blood monitoring in IG treatment

Background

ABN immunoglobulin (Ig) guidelines advise routine FBC and U and E monitoring with every treatment episode and screening for IgA deficiency.

Aims

We audited compliance in inflammatory neuropathy patients on longterm treatment in two UK Neurology departments. We looked for evidence of clinically relevant haematological or AKI Ig-related events.

Methods

Data was collected from Nov 2015 to Nov 2017. Accepted definitions for clinically and/or biochemically significant haemolysis, neutropenia, thrombocytopenia and AKI were used.

Results

1919 treatment episodes in 90 patients were analysed. Mean age (SD)=57.6 (14.4)years, 69.1% male, 74% CIDP (26% MMN), 94% IVIg (6% SCIg). Mean dose=1.57 (0.74) g/kg/month or 97.1 (37.3) g/infusion. No clinically significant episodes of haemolysis, neutropenia, thrombocytopenia or AKI occurred in relation to Ig treatment. An asymptomatic drop of >10 g/L Hb occurred in 68/1919 episodes in 38 individuals (3.5%); mean reduction 17.7 g/L, lowest Hb 99 g/L. Two patients with CRF (stage 3) received 28 (IV) and 104 (SC) infusions respectively without impact on eGFR. Two individuals with relative IgA deficiency (0.38 g/L, 0.4 g/L) received 16 infusions over 1.5 years without complications.

Conclusions

No clinically significant Ig-related events were identified in this representative cohort. We suggest annual screening or clinically indicated testing as safe and more appropriate in longterm IVIg use.

Clinical spectrum, treatment and outcome of children with suspected diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy

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The diagnosis of CIDP can be challenging.

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In our cohort 52% were diagnosed as CIDP on re-evaluation.

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Cranial nerve abnormality is rare and may be only presenting symptom.

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Children require long-term follow up as the course may be protracted.

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With early treatment majority have good recovery and maintain ambulation.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a treatable chronic disorder of the peripheral nervous system. We retrospectively studied 30 children with a suspected diagnosis of CIDP. The diagnosis of CIDP was compared against the childhood CIDP revised diagnostic criteria 2000. Of the 30 children, five did not meet the criteria and four others met the criteria but subsequently had alternative diagnosis, leaving a total of 21 children (12 male) with CIDP as the final diagnosis. Thirteen children presented with chronic symptom-onset (>8 weeks). The majority presented with gait difficulties or pain in legs (n = 16). 12 children (57%) met the neurophysiological criteria and 18/19 (94%) met the cerebrospinal fluid criteria. Nerve biopsy was suggestive in 3/9 (33%), with magnetic resonance imaging supportive in 9/20 (45%). Twenty-one children received immuno-modulatory treatment at first presentation, of which majority (n = 19, 90%) received IVIG (immunoglobulin) monotherapy with 13 (68%) showing a good response. 8 children received second line treatment with either IVIG or steroids or plasmapharesis (PE) and 4 needed other immune-modulatory agents. During a median follow-up of 3.6 years, 9 (43%) had a monophasic course and 12 (57%) had a relapsing–remitting course. At last paediatric follow up 7 (33%) were off all treatment, 9 (43%) left with no or minimal residual disability and 6 (28%) children were walking with assistance (n = 3) or were non-ambulant (n = 3). Our review highlights challenges in the diagnosis and management of paediatric CIDP. It also confirms that certain metabolic disorders may mimic CIDP.

Human biallelic MFN2 mutations induce mitochondrial dysfunction, upper body adipose hyperplasia, and suppression of leptin expression

MFN2 encodes mitofusin 2, a membrane-bound mediator of mitochondrial membrane fusion and inter-organelle communication. MFN2 mutations cause axonal neuropathy, with associated lipodystrophy only occasionally noted, however homozygosity for the p.Arg707Trp mutation was recently associated with upper body adipose overgrowth. We describe similar massive adipose overgrowth with suppressed leptin expression in four further patients with biallelic MFN2 mutations and at least one p.Arg707Trp allele. Overgrown tissue was composed of normal-sized, UCP1-negative unilocular adipocytes, with mitochondrial network fragmentation, disorganised cristae, and increased autophagosomes. There was strong transcriptional evidence of mitochondrial stress signalling, increased protein synthesis, and suppression of signatures of cell death in affected tissue, whereas mitochondrial morphology and gene expression were normal in skin fibroblasts. These findings suggest that specific MFN2 mutations cause tissue-selective mitochondrial dysfunction with increased adipocyte proliferation and survival, confirm a novel form of excess adiposity with paradoxical suppression of leptin expression, and suggest potential targeted therapies.