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BackgroundMitochondrial progressive external ophthalmoplegia (PEO) encompasses a broad spectrum of clinical and genetic disorders. We describe the phenotypic subtypes of PEO and its correlation with molecular defects and propose a diagnostic algorithm.MethodsRetrospective analysis of the clinical, pathological and genetic features of 89 cases.ResultsThree main phenotypes were found: ‘pure PEO’ (42%), consisting of isolated palpebral ptosis with ophthalmoparesis; Kearns-Sayre syndrome (10%); and ‘PEO plus’, which associates extraocular symptoms, distinguishing the following subtypes: : myopathic (33%), bulbar (12%) and others (3%). Muscle biopsy was the most accurate test, showing mitochondrial changes in 95%. Genetic diagnosis was achieved in 96% of the patients. Single large-scale mitochondrial DNA (mtDNA) deletion was the most frequent finding (63%), followed by multiple mtDNA deletions (26%) due to mutations in TWNK (n=8), POLG (n=7), TK2 (n=6) or RRM2B (n=2) genes, and point mtDNA mutations (7%). Three new likely pathogenic mutations were identified in the TWNK and MT-TN genes.ConclusionsPhenotype–genotype correlations cannot be brought in mitochondrial PEO. Muscle biopsy should be the first step in the diagnostic flow of PEO when mitochondrial aetiology is suspected since it also enables the study of mtDNA rearrangements. If no mtDNA deletions are identified, whole mtDNA sequencing should be performed.

Autosomal dominant mutations in the TWNK gene, which encodes a mitochondrial DNA helicase, cause adult-onset progressive external ophthalmoplegia (PEO) and PEO-plus presentations. In this retrospective observational study, we describe clinical and complementary data from 25 PEO patients with mutations in TWNK recruited from the Hospital 12 de Octubre Mitochondrial Disorders Laboratory Database. The mean ages of onset and diagnosis were 43 and 63 years, respectively. Family history was positive in 22 patients. Ptosis and PEO (92% and 80%) were the most common findings. Weakness was present in 48%, affecting proximal limbs, neck, and bulbar muscles. Exercise intolerance was present in 28%. Less frequent manifestations were cardiac (24%) and respiratory (4%) involvement, neuropathy (8%), ataxia (4%), and parkinsonism (4%). Only 28% had mild hyperCKemia. All 19 available muscle biopsies showed signs of mitochondrial dysfunction. Ten different TWNK mutations were identified, with c.1361T>G (p.Val454Gly) and c.1070G>C (p.Arg357Pro) being the most common. Before definitive genetic confirmation, 56% of patients were misdiagnosed (36% with myasthenia, 20% with oculopharyngeal muscle dystrophy). Accurate differential diagnosis and early confirmation with appropriately chosen complementary studies allow genetic counseling and the avoidance of unnecessary treatments. Thus, mitochondrial myopathies must be considered in PEO/PEO-plus presentations, and particularly, TWNK is an important cause when positive family history is present.

[Background and purpose] Prognosis of myasthenia gravis (MG) in patients with thymoma is not well established. Moreover, it is not clear whether thymoma recurrence or unresectable lesions entail a worse prognosis of MG., [Methods] This multicenter study was based on data from a Spanish neurologist-driven MG registry. All patients were aged >18 years at onset and had anti-acetylcholine receptor antibodies. We compared the clinical data of thymomatous and nonthymomatous patients. Prognosis of patients with recurrent or nonresectable thymomas was assessed., [Results] We included 964 patients from 15 hospitals; 148 (15.4%) had thymoma-associated MG. Median follow-up time was 4.6 years. At onset, thymoma-associated MG patients were younger (52.0 vs. 60.4 years, p < 0.001), had more generalized symptoms (odds ratio [OR]: 3.02, 95% confidence interval [CI]: 1.95–4.68, p < 0.001) and more severe clinical forms according to the Myasthenia Gravis Foundation of America (MGFA) scale (OR: 1.6, 95% CI: 1.15–2.21, p = 0.005). Disease severity based on MGFA postintervention status (MGFA-PIS) was higher in thymomatous patients at 1 year, 5 years, and the end of follow-up. Treatment refractoriness and mortality were also higher (OR: 2.28, 95% CI: 1.43–3.63, p = 0.001; hazard ratio: 2.46, 95% CI: 1.47–4.14, p = 0.001). Myasthenic symptoms worsened in 13 of 27 patients with recurrences, but differences in long-term severity were not significant. Fifteen thymomatous patients had nonresectable thymomas with worse MGFA-PIS and higher mortality at the end of follow-up., [Conclusions] Thymoma-associated MG patients had more severe myasthenic symptoms and worse prognosis. Thymoma recurrence was frequently associated with transient worsening of MG, but long-term prognosis did not differ from nonrecurrent thymoma. Patients with nonresectable thymoma tended to present severe forms of MG., This work is supported by Fondo de Investigaciones Sanitarias (FIS) grant FIS19/01774, Instituto de Salud Carlos III and cofunded by the European Union (ERDF/ESF, A Way to Make Europe/Investing in Your Future). Rodrigo Álvarez-Velasco was supported by a PhD for Medical Doctors grant from the Pla Estratègic de Recerca i Innovació en Salut (PERIS), Generalitat de Catalunya (SLT008/18/00207). Elena Cortés-Vicente was supported by a Juan Rodés grant (JR19/00037) from the Fondo de Investigación en Salud, Instituto de Salud Carlos III, Ministry of Health (Spain).

Background Guillain-Barre syndrome (GBS) is an acute inflammatory neuropathy with a heterogeneous presentation. Although some evidences support the role of autoantibodies in its pathogenesis, the target antigens remain unknown in a substantial proportion of GBS patients. The objective of this study is to screen for autoantibodies targeting peripheral nerve components in Guillain-Barre syndrome. Methods Autoantibody screening was performed in serum samples from all GBS patients included in the International GBS Outcome study by 11 different Spanish centres. The screening included testing for anti-ganglioside antibodies, anti-nodo/paranodal antibodies, immunocytochemistry on neuroblastoma-derived human motor neurons and murine dorsal root ganglia (DRG) neurons, and immunohistochemistry on monkey peripheral nerve sections. We analysed the staining patterns of patients and controls. The prognostic value of anti-ganglioside antibodies was also analysed. Results None of the GBS patients (n = 100) reacted against the nodo/paranodal proteins tested, and 61 (61%) were positive for, at least, one anti-ganglioside antibody. GBS sera reacted strongly against DRG neurons more frequently than controls both with IgG (6% vs 0%; p = 0.03) and IgM (11% vs 2.2%; p = 0.02) immunodetection. No differences were observed in the proportion of patients reacting against neuroblastoma-derived human motor neurons. Reactivity against monkey nerve tissue was frequently detected both in patients and controls, but specific patterns were only detected in GBS patients: IgG from 13 (13%) patients reacted strongly against Schwann cells. Finally, we confirmed that IgG anti-GM1 antibodies are associated with poorer outcomes independently of other known prognostic factors. Conclusion Our study confirms that (1) GBS patients display a heterogeneous repertoire of autoantibodies targeting nerve cells and structures; (2) gangliosides are the most frequent antigens in GBS patients and have a prognostic value; (3) further antigen-discovery experiments may elucidate other potential antigens in GBS.

Using recent optimized electrodiagnostic criteria sets, we aimed at verifying the accuracy of initial nerve conduction studies (NCS) in classic very early Guillain-Barre syndrome (VEGBS), ≤ 4 days after onset, compared with the results of serial NCS. This is a retrospective study based on unreported and consecutive VEGBS patients admitted to two university hospitals between 2015 and 2019. Each patient had serial NCS in at least four nerves. Initial NCS studies were done within 4 days after onset, and serial ones from days 20 to 94. Electrophysiological recordings were blinded evaluated by four of the authors, GBS subtype being established accordingly. Seven adult classic VEGBS patients were identified with a median age of 58 years. At first NCS, GBS subtyping was only possible in 1 case that exhibited an axonal pattern, the remaining patterns being equivocal in 3, and mixed (combining axonal and demyelinating criteria) in the remaining 3. Upon serial NSC there was a rather intricate evolution of electrophysiological GBS patterns, 3 of them being classified as axonal or demyelinating, and the remaining 4 as equivocal or mixed. NCS in VEGBS systematically allows detection of changes suggestive of peripheral neuropathy, though even after serial studies accurate GBS subtyping was only possible in 43% of cases. We provide new pathophysiological insights for better understanding of the observed electrophysiological changes.

ObjectiveTo study baseline serum neurofilament light chain (sNfL) levels as a prognostic biomarker in Guillain-Barré syndrome (GBS).MethodsWe measured NfL in serum (98 samples) and cerebrospinal fluid (CSF) (24 samples) of patients with GBS prospectively included in the International GBS Outcome Study (IGOS) in Spain using single-molecule array (SiMoA) and compared them with 53 healthy controls (HCs). We performed multivariable regression to analyse the association between sNfL levels and functional outcome at 1 year.ResultsPatients with GBS had higher NfL levels than HC in serum (55.49 pg/mL vs 9.83 pg/mL, p319 pg/mL), inability to run (>248 pg/mL) and ability to run (ConclusionBaseline sNfL levels are increased in patients with GBS, are associated with disease severity and axonal variants and have an independent prognostic value in patients with GBS.

Purpose: Neuropathy is the dose-limiting toxicity of paclitaxel and a major cause for decreased quality of life. Genetic factors have been shown to contribute to paclitaxel neuropathy susceptibility; however, the major causes for interindividual differences remain unexplained. In this study, we identified genetic markers associated with paclitaxel-induced neuropathy through massive sequencing of candidate genes. Experimental Design: We sequenced the coding region of 4 EPHA genes, 5 genes involved in paclitaxel pharmacokinetics, and 30 Charcot–Marie–Tooth genes, in 228 cancer patients with no/low neuropathy or high-grade neuropathy during paclitaxel treatment. An independent validation series included 202 paclitaxel-treated patients. Variation-/gene-based analyses were used to compare variant frequencies among neuropathy groups, and Cox regression models were used to analyze neuropathy along treatment. Results: Gene-based analysis identified EPHA6 as the gene most significantly associated with paclitaxel-induced neuropathy. Low-frequency nonsynonymous variants in EPHA6 were present exclusively in patients with high neuropathy, and all affected the ligand-binding domain of the protein. Accumulated dose analysis in the discovery series showed a significantly higher neuropathy risk for EPHA5/6/8 low-frequency nonsynonymous variant carriers [HR, 14.60; 95% confidence interval (CI), 2.33–91.62; P = 0.0042], and an independent cohort confirmed an increased neuropathy risk (HR, 2.07; 95% CI, 1.14–3.77; P = 0.017). Combining the series gave an estimated 2.5-fold higher risk of neuropathy (95% CI, 1.46–4.31; P = 9.1 × 10−4). Conclusions: This first study sequencing EPHA genes revealed that low-frequency variants in EPHA6, EPHA5, and EPHA8 contribute to the susceptibility to paclitaxel-induced neuropathy. Furthermore, EPHA's neuronal injury repair function suggests that these genes might constitute important neuropathy markers for many neurotoxic drugs. Clin Cancer Res; 23(5); 1227–35. ©2016 AACR.

[Objective] To describe the characteristics of patients with very-late-onset myasthenia gravis (MG)., [Methods] This observational cross-sectional multicenter study was based on information in the neurologist-driven Spanish Registry of Neuromuscular Diseases (NMD-ES). All patients were >18 years of age at onset of MG and onset occurred between 2000 and 2016 in all cases. Patients were classified into 3 age subgroups: early-onset MG (age at onset, [Results] A total of 939 patients from 15 hospitals were included: 288 (30.7%) had early-onset MG, 227 (24.2%) late-onset MG, and 424 (45.2%) very-late-onset MG. The mean follow-up was 9.1 years (SD 4.3). Patients with late onset and very late onset were more frequently men (p < 0.0001). Compared to the early-onset and late-onset groups, in the very-late-onset group, the presence of anti–acetylcholine receptor (anti-AChR) antibodies (p < 0.0001) was higher and fewer patients had thymoma (p < 0.0001). Late-onset MG and very-late-onset MG groups more frequently had ocular MG, both at onset (, [Conclusions] Patients with MG are primarily ≥65 years of age with anti-AChR antibodies and no thymoma. Although patients with very-late-onset MG may present life-threatening events at onset, they achieve a good outcome with fewer immunosuppressants when diagnosed and treated properly.

Objective We report the findings from the Spanish Society of Neurology's NeuroCOVID-19 Registry. Methods We performed a multicentre study of patients with neurological manifestations of COVID-19. Participating physicians reported demographic, clinical, and paraclinical data and judged the involvement of COVID-19 in causing neurological symptoms. Results A total of 233 cases were submitted, including 74 different combinations of manifestations. The most frequently reported were stroke (27%), neuromuscular symptoms (23.6%), altered mental status (23.6%), anosmia (17.6%), headache (12.9%), and seizures (11.6%). The mean age of patients was 61.1 years, with 42.1% being women; a higher proportion of women was recorded among patients with altered mental status, anosmia, and headache. The onset of symptoms differed within categories. Onset of anosmia occurred a mean (standard deviation) of 2.9 (2.5) days after the first general symptom, whereas neuromuscular symptoms appeared after 13.9 (10.1) days. Neurological symptoms were persistent in 33% of patients. General symptoms were present in 97.7% of patients, and results from general laboratory studies were abnormal in 99.4% of patients. Cerebrospinal fluid analysis findings were abnormal in 62.7% of the cases in which this test was performed (n = 51), but positive results for SARS-CoV-2 were only found in one case. Conclusions The neurological manifestations of COVID-19 are diverse. Anosmia, myalgia, and headache occur earlier in the course of the disease. Altered mental status, neuromuscular symptoms, and stroke are associated with greater severity. COVID-19 must be incorporated into most clinical and radiological differential diagnoses. COVID-19 may cause persistent and disabling neurological symptoms., Highlights • NeuroCovid-19 is polymorph: Authors reported >70 different combinations of neurological syndromic presentations. • The timing of the neurological symptoms differ: from the early onset (anosmia, headache, myalgia) to later stages (altered mental status, seizures, stroke, neuromuscular symptoms). • Some neurological symptoms might persist, as headache or anosmia; while other may cause persistent disability, as stroke or polyneuropathies. • Cerebrospinal fluid was frequently abnormal but direct isolation of SARS-CoV-2 occurred only in 1/233 cases. • Neurologists must be prepared to face the various neurological syndromes that may be associated with Covid-19 infection.

Background and objectiveOculopharyngeal muscular dystrophy (OPMD) is a genetic disorder caused by an abnormal expansion of GCN triplets within thePABPN1gene. Previous descriptions have focused on lower limb muscles in small cohorts of patients with OPMD, but larger imaging studies have not been performed. Previous imaging studies have been too small to be able to correlate imaging findings to genetic and clinical data.MethodsWe present cross-sectional, T1-weighted muscle MRI and CT-scan data from 168 patients with genetically confirmed OPMD. We have analysed the pattern of muscle involvement in the disease using hierarchical analysis and presented it as heatmaps. Results of the scans were correlated with genetic and clinical data.ResultsFatty replacement was identified in 96.7% of all symptomatic patients. The tongue, theadductor magnusand thesoleuswere the most commonly affected muscles. Muscle pathology on MRI correlated positively with disease duration and functional impairment.ConclusionsWe have described a pattern that can be considered characteristic of OPMD. An early combination of fat replacement in the tongue,adductor magnusandsoleuscan be helpful for differential diagnosis. The findings suggest the natural history of the disease from a radiological point of view. The information generated by this study is of high diagnostic value and important for clinical trial development.

Background and objectives: Steinert's disease or myotonic dystrophy type 1 (MD1), (OMIM 160900), is the most prevalent myopathy in adults. It is a multisystemic disorder with dysfunction of virtually all organs and tissues and a great phenotypical variability, which implies that it has to be addressed by different specialities with experience in the disease. The knowledge of the disease and its management has changed dramatically in recent years. This guide tries to establish recommendations for the diagnosis, prognosis, follow-up and treatment of the complications of MD1. Material and methods: Consensus guide developed through a multidisciplinary approach with a systematic literature review. Neurologists, pulmonologists, cardiologists, endocrinologists, neuropaediatricians and geneticists have participated in the guide. Recommendations: The genetic diagnosis should quantify the number of CTG repetitions. MD1 patients need cardiac and respiratory lifetime follow-up. Before any surgery under general anaesthesia, a respiratory evaluation must be done. Dysphagia must be screened periodically. Genetic counselling must be offered to patients and relatives. Conclusion: MD1 is a multisystemic disease that requires specialised multidisciplinary follow-up. Resumen: Antecedentes y objetivos: La enfermedad de Steinert o distrofia miotónica tipo 1 (DM1), (OMIM 160900) es la miopatía más prevalente en el adulto. Es una enfermedad multisistémica con alteración de prácticamente todos los órganos y tejidos y una variabilidad fenotípica muy amplia, lo que implica que deba ser atendida por diferentes especialistas que dominen las alteraciones más importantes. En los últimos años se ha avanzado de manera exponencial en el conocimiento de la enfermedad y en su manejo. El objetivo de la guía es establecer recomendaciones para el diagnóstico, el pronóstico, el seguimiento y el tratamiento de las diferentes alteraciones de la DM1. Material y métodos: Esta guía de consenso se ha realizado de manera multidisciplinar. Se ha contado con neurólogos, neumólogos, cardiólogos, endocrinólogos, neuropediatras y genetistas que han realizado una revisión sistemática de la literatura. Recomendaciones: Se recomienda realizar un diagnóstico genético con cuantificación precisa de tripletes CTG. Los pacientes con DM1 deben seguir control cardiológico y neumológico de por vida. Antes de cualquier cirugía con anestesia general debe realizarse una evaluación respiratoria. Debe monitorizarse la presencia de síntomas de disfagia periódicamente. Debe ofrecerse consejo genético a los pacientes con DM1 y a sus familiares. Conclusión: La DM1 es una enfermedad multisistémica que requiere un seguimiento en unidades especializadas multidisciplinares.

Background Peripheral neuropathy is the dose-limiting toxicity of many oncology drugs, including paclitaxel. There is large interindividual variability in the neuropathy, and several risk factors have been proposed; however, many have not been replicated. Here we present a comprehensive study aimed at identifying treatment and physiopathology-related paclitaxel-induced neuropathy risk factors in a large cohort of well-characterized patients. Patients and Methods Analyses included 503 patients with breast or ovarian cancer who received paclitaxel treatment. Paclitaxel dose modifications caused by the neuropathy were extracted from medical records and patients self-reported neuropathy symptoms were collected. Multivariate logistic regression analyses were performed to identify concomitant medications and comorbidities associated with paclitaxel-induced neuropathy. Results Older patients had higher neuropathy: for each increase of 1 year of age, the risk of dose modifications and grade 3 neuropathy increased 4% and 5%, respectively. Cardiovascular drugs increased the risk of paclitaxel dose reductions (odds ratio [OR], 2.51; p = .006), with a stronger association for beta-adrenergic antagonists. The total number of concomitant medications also showed an association with dose modifications (OR, 1.25; p = .012 for each concomitant drug increase). A dose modification predictive model that included the new identified factors gave an area under the curve of 0.74 (p = 1.07 x 10(-10)). Preexisting nerve compression syndromes seemed to increase neuropathy risk. Conclusion Baseline characteristics of the patients, including age and concomitant medications, could be used to identify individuals at high risk of neuropathy, personalizing chemotherapy treatment and reducing the risk of severe neuropathy. Implications for Practice Peripheral neuropathy is a common adverse effect of many cancer drugs, including chemotherapeutics, targeted therapies, and immune checkpoint inhibitors. About 40% of survivors of cancer have functional deficits caused by this toxicity, some of them irreversible. Currently, there are no effective treatments to prevent or treat this neuropathy. This study, performed in a large cohort of well-characterized patients homogenously treated with paclitaxel, identified concomitant medications, comorbidities, and demographic factors associated with peripheral neuropathy. These factors could serve to identify patients at high risk of severe neuropathy for whom alternative non-neurotoxic alternatives may be considered. Sin financiación 5.025 JCR (2019) Q2, 63/244 Oncology 2.613 SJR (2019) Q1, 26/214 Cancer Research, 30/367 Oncology, 90/2754 Medicine (miscellaneous) No data IDR 2019 UEM

Background and purpose Myasthenia gravis (MG) may become life-threatening if patients have respiratory insufficiency or dysphagia. This study aimed to determine the incidence, demographic characteristics, risk factors, response to treatment and outcome of these life-threatening events (LTEs) in a recent, population-based sample of MG patients. Methods A retrospective analysis of MG patients who presented with an LTE between 2000 and 2013 was performed. Participants were identified from a neuromuscular diseases registry in Spain that includes 648 patients with MG (NMD-ES). Results Sixty-two (9.56%) patients had an LTE. Thirty-two were classified as class V according to the MG Foundation of America, and 30 as class IVB. Fifty per cent were previously diagnosed with MG and median duration of the disease before the LTE was 24 months (3–406). The most common related factor was infection (n = 18). All patients received intravenous human immunoglobulin; 11 had a second infusion and six had plasma exchange. Median time to feeding tube removal was 13 days (1–434). Median time to weaning from ventilation was 12 days (3–176), and it was significantly shorter in late onset MG (≥50 years) (P = 0.019). LTEs improved

Antinuclear antibodies (ANAs) are a spectrum of autoantibodies targeted to various nuclear and cytoplasmic components of the cells. They are very useful as serological markers for different autoimmune disease, like systemic lupus erythematosus (SLE), Sjogren's syndrome (SS), scleroderma, polymyositis, or mixed connective tissue disease. In these years, an increasing attention has been focussed in the relationship between tumours and autoimmunity. Different authors have demonstrated that ANAs are presented, not only in autoimmune diseases, also in serum of patients with different types of cancers. These data suggested that ANAs could be involved in the pathogenesis of cancer as well as other premalignant disease. In this review, we are going to describe all data reported about the presence of these antibodies in samples from patients with cancer as well as the potential role of some of these proteins in early detection and prognosis.

Oxaliplatin is one of the main drugs used in digestive tumors treatment. Peripheral neuropathy is a well-recognized dose-limiting toxicity of OXL. Two types of neuropathy have been described with this agent: acute or transient and chronic or persistent, with different etiology, clinical manifestations and prognosis. This paper is an exhaustive review about the main aspects of oxaliplatin induced peripheral neuropathy, focus in clinical features, treatment, prevention strategies and future approach.

We present the case of a patient with a solitary left frontoparietal brain metastasis of melanoma previously treated with surgery. Three months later, the patient was admitted to the emergency room in a confusional state with meningeal signs. A cerebrospinal fluid (CSF) test and magnetic resonance imaging findings suggested a subarachnoid haemorrhage (SAH) and/or meningeal carcinomatosis. The results of a cytological examination of the CSF showed neoplastic epithelial cells consistent with metastatic melanoma cells. Resection of metastatic posterior fossa lesions is often cited as a risk factor for leptomeningeal dissemination, however, when the resection is limited to the anterior fossa, this complication is relatively rare. In contrast, SAH may be a complication of leptomeningeal dissemination and responsible for acute meningeal syndrome. Treatment with high doses of corticoids did not show any improvement, and intrathecal chemotherapy was not possible due to the patient's poor functional status. She succumbed 1 week after admission.

We have with great interest read the pharmacogenetic study by Abraham and colleagues ([1][1]) reporting SNPs associated with paclitaxel-induced neuropathy. The identification of markers predictive of sensory neuropathy is an important clinical problem for taxanes, vinca-alkaloids, platinum compounds

Permanent central venous catheters (CVC), such as Port-a-Cath®, Hickmann® or PICC®, are widely used in oncology patients for cancer treatment. Thrombosis is a frequent complication that should be ruled out, as it is associated with potentially severe infection and hemodynamic consequences. This is the case report of a male patient who was undergoing chemotherapy for colon cancer. The patient presented with an atrial mass secondary to a CVC-related organized thrombus located inside the atrial cavity. The mass was inducing a massive right-to-left intracardial shunt due to a persistent foramen ovale and signs of respiratory failure that required surgical intervention to remove the intracardial mass.

Purpose: Paclitaxel, a widely used chemotherapeutic drug, can cause peripheral neuropathies leading to dose reductions and treatment suspensions and decreasing the quality of life of patients. It has been suggested that genetic variants altering paclitaxel pharmacokinetics increase neuropathy risk, but the major causes of interindividual differences in susceptibility to paclitaxel toxicity remain unexplained. We carried out a whole-exome sequencing (WES) study to identify genetic susceptibility variants associated with paclitaxel neuropathy. Experimental Design: Blood samples from 8 patients with severe paclitaxel-induced peripheral neuropathy were selected for WES. An independent cohort of 228 cancer patients with complete paclitaxel neuropathy data was used for variant screening by DHPLC and association analysis. HEK293 cells were used for heterologous expression and characterization of two novel CYP3A4 enzymes. Results: WES revealed 2 patients with rare CYP3A4 variants, a premature stop codon (CYP3A4*20 allele) and a novel missense variant (CYP3A4*25, p.P389S) causing reduced enzyme expression. Screening for CYP3A4 variants in the independent cohort revealed three additional CYP3A4*20 carriers, and two patients with missense variants exhibiting diminished enzyme activity (CYP3A4*8 and the novel CYP3A4*27 allele, p.L475V). Relative to CYP3A4 wild-type patients, those carrying CYP3A4 defective variants had more severe neuropathy (2- and 1.3-fold higher risk of neuropathy for loss-of-function and missense variants, respectively, P = 0.045) and higher probability of neuropathy-induced paclitaxel treatment modifications (7- and 3-fold higher risk for loss-of-function and missense variants, respectively, P = 5.9 × 10−5). Conclusion: This is the first description of a genetic marker associated with paclitaxel treatment modifications caused by neuropathy. CYP3A4 defective variants may provide a basis for paclitaxel treatment individualization. Clin Cancer Res; 21(2); 322–8. ©2014 AACR.

Inflammatory myopathies are a heterogeneous group of myopathies in which there is biopsy-evident inflammation. In its evaluation it is essential to use neurophysiological techniques that provide information on the nature of the process. This paper reviews the electromigram pattern characteristic of inflammatory myopathies, its diagnostic value, limitations, and some clues on the interpretation of the results of neurophysiological techniques in the assessment of inflammatory myopathies.

Chemotherapy-induced peripheral neuropathy (CIN) is a common toxicity of anticancer treatment and its incidence is growing. It significantly affects quality of life and is a dose-limiting factor that interferes with treatment. Its diagnosis can be established in clinical terms but some complementary tests can help when the diagnosis is difficult. There is still no proven method to prevent it that has become a standard of care in spite of the huge amount of investigation carried out in recent years. There are promising strategies that could help reduce the burden of this complication. This review will suggest an approach to the diagnosis of these disorders and provide an update on new therapies.

Introduccion. Las miopatias producidas por toxinas industriales y biologicas son entidades poco frecuentes, pero de gran interes, ya que su correcta identificacion puede permitir retirar el toxico y obtener la curacion o evitar lesiones irreversibles. Objetivo. Describir las miopatias toxicas mas frecuentes. Desarrollo. Se discute la epidemiologia, manifestaciones clinicas y manejo clinico de las miopatias toxicas. Conclusiones. Las miopatias toxicas son poco frecuentes y dificiles de diagnosticar. Existe poca bibliografia al respecto. Es necesario estar familiarizado con ellas, puesto que un diagnostico rapido permite la curacion o evitar secuelas importantes.

9073 Background: Oxaliplatin (OXL) is an active drug in digestive tumors. Oxaliplatin induced peripheral neuropathy (OIN) is the main dose limiting toxicity. Around 60-80% of patients developed a mild cold-induced neurotoxicity that used to disappear few days after but in 15% became a persistent neuropathy. The pathophysiology of oxaliplatin-induced neuropathy (OIN) remains unclear, preclinical studies suggest involvement of voltage Na channels. SCN9A gene codifies to Na channels α subunit highly expressed in nociceptive neurons. Mutations in SCN9A are involved in alterations in neuropatic pain perception. This study tried to identify if variants in SCN9A could be associated to a higher risk to OIN. Methods: Serum were obtained from 100 patients with digestive cancer (colorectal, gastric, pancreatic and bile duct) treated with OXL (adjuvant or advanced setting) in Infanta Sofía University Hospital. No diabetes or hypotiroidism were detected. Patients were divided in two groups according to the development of OIN: Arm A 50 patients diagnosed of grade 2-3 OIN after 6 courses and Arm B 50 with no OIN. The evaluation of severity of the OIN by a neurologist included a classification according to NCI-CTC and OSNS scales and conduction studies. Genomic DNA was isolated from serum and variants of SCN9A were analyzed by PCR-RFLP. The relation between SCN9A genotype and the development of severe OIN was the primary aim Results: One hundred patients were enrolled between May 2010-November 2011. 56 (56%) females and 44 (44%) males; mean age was 62; mean ECOG was 1; primary tumor were colorectal 81 pts (81%), gastric 10 (10%); 8 (8%) pancreto-biliar and anus 1(1%). Stage were classified in localized 65 (65%) and advanced (35%). The chemotherapy regimen included: 94 (94%) XELOX, 1 (1%) XELOX-Herceptin and 5 (5%) EOX regimen. The mean of cycles were 7 (1-14). Mean OXL dose intensity was 100mg/m2.The mean PFS was 23 months. High expression of SCN9A variants were detected in patients 26/50, 52% arm A and in 5/50, 10% arm B patients, suggesting a possible relationship beetwen the development of OIN and SCN9A genotype (p=0.04). Conclusions: SCN9A polimorphysms may help to identify those patients with a higher risk to develop oxaliplatin induced neuropathy.

We present the case of a 70-year-old woman with emphysematous cys- titis. She was a diabetic patient and she was on chemotherapy treatment for a breast cancer. She complaint of severe asthenia and pain in her right lower extremity, but no fever or urinary symptoms. A computed tomography (CT) scan was suggestive of severe emphysematous cystitis. Emphysematous cystitis is a rare clinically entity, more commonly seen in diabetic, immunocompromised patients. A conservative treatment approach using antibiotics and bladder catheterization is typically suc- cessful, with a complication rate less than 20%.