Miopatías inflamatorias idiopáticas: una mirada actualizada al diagnóstico y el manejo / Idiopathic inflammatory myopathies: a review

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of acquired immune-mediated diseases, which typically involve the striated muscle with a variable involvement of the skin and other organs. Clinically, they are characterized by proximal muscle weakness, elevation of muscle enzymes, myopathic changes on electromyography and an abnormal muscle biopsy. The different IIM have been classified according to their distinctive histopathologic features in dermatomyositis (DM), polymyositis (PM), inclusion body myositis (IBM) and immune-mediated necrotizing myopathy (IMNM). Several myositis-specific antibodies are associated with the different phenotypes, as well as with different risk of neoplastic disease and systemic complications. The basis for the treatment of DM, PM, and IMNM is immunosuppression. For IBM there are only symptomatic treatments. Steroids, associated or not with other immunosuppressant drugs, are the first line of treatment. Biologic drugs will allow future individualized therapies. The 10-year survival of DM, PM and IMNM is 62 to 90%. The leading causes of death are neoplastic, lung and cardiac complications. IBM does not impair survival, although it affects the quality of life.

Compromiso neuropático y autonómico en Enfermedad de Fabry: presentación de casos clínicos / Neuropathy and Fabry's disease: report of five cases

Fabry's disease is an X-linked multisistemic lisosomal storage disorder caused by deficiency or absence in α-Galatosidase A. Symptoms develop early in childhood with small fiber neuropathy, autonomic disorders and skin lesions (angiokeratomas). More severe in males, patients develop over years heart disease (hypertrophic cardiomyopathy, bradycardia), proteinuria, renal failure, transient ischemic attacks and stroke, associated with decreased life expectancy. We report five patients with Fabry's disease aged between 21 to 56 years and with family history. Neuropathic symptoms are described and neurophysiological testing findings of nerve conduction studies, quantitative sensory testing, autonomic testing and sympathetic skin response are presented.

Descripción electrofisiològica del síndrome de túnel carpiano según edad en pacientes adultos / Electrophysiological severity of carpal tunnel syndrome according to age in adult patients

Background: Carpal tunnel syndrome (CTS) represents 90% of entrapment neuropathies. Severity may be greater in older patients. Aim: To describe the electrophysiological findings in adult patients with CTS and determine if severity is related to age. Material and Methods: Descriptive and retrospective study of electrophysiological findings in patients over 18 years of age with clinical suspicion of CTS, studied between January 2011 and December 2015. Neurophysiological severity was classified in 3 grades, comparing them by age, gender and laterality. Results: Of 1156 patients subjected to electrophysiological studies due to a clinical suspicion of CTS, 690 (60%) had electrophysiological features of the disease. In 274 patients (24%) the compromise was mild, in 162 (14%) it was moderate and in 254 (22%) it was severe. There was a positive association between age and CTS severity (p < 0.01). Severity was significantly greater in males than females (p < 0.01). Bilateral CTS was present in 471 patients (68%), which was associated with increased age and severity (p < 0.01). Conclusions: Electrophysiological severity in CTS increases with age. Other factors associated with higher severity are male gender and bilateral disease.

Polirradiculoneuritis aguda asociada a infección por Virus Herpes Humano 7 en un paciente adulto inmunocompetente / Acute polyradiculoneuropathy associated with human Herpes Virus 7 in an immunocompetent patient: case report

Human herpes virus 7 (HHV-7) is a cause of encephalitis, meningitis and myeloradiculoneuropathy in adults who are immunocompetent or with immunosuppression. The involvement of the peripheral nervous system is always associated with myelitis. We report a case of acute polyradiculoneuropathy due to HHV-7, without involvement of central nervous system, in an immunocompetent patient. A 35-years-old man complained of lumbar pain radiating to both buttocks. On examination muscle strength and tendon reflexes were normal. He had asymmetric pinprick and light touch saddle hypoesthesia and also in the perineal region, dorsum and lateral aspect of the left foot. Magnetic resonance imaging showed mild thickening and contrast enhancement of cauda equina nerve roots. Polymerase chain reaction performed on cerebrospinal fluid was positive for HVV-7. Other inflammatory, infectious and neoplastic etiologies were ruled out. Lumbar pain and hypoesthesia improved progressively and neurological examination was normal after one month. He did not receive antiviral therapy.

Sensory Peripheral Nerve Function in Chilean Elderly Consuming Folic Acid Fortified Flour: Relationship to Plasma Folate and a Novel Combined Biomarker of B12 Status. European Journal of Nutrition & Food Safety. 2015 Special issue; 5(5): 1067-1068.

Objectives: It has been reported that low vitamin B12 status and high serum folate is associated with anemia and cognitive impairment. However, few data are available on neurophysiological outcomes, such as peripheral neurophysiology. The objective was to assess associations between folate, B12 and sensory peripheral nerve conduction in Chilean elderly exposed to folic acid fortification. Methods: The average of the left and right distal sensory conduction latency of the sural nerve, and conduction velocity of the right peroneus nerve were measured in 159 community-dwelling older Chilean. Serum folate, B12, Hcy, MMA, and holoTC were determined. B12 status was defined based on: w=log_10 (holoTC*B12)/(MMA*Hcy)-(age factor) (Fedosov SN, Clin. Chim. Acta. 2013). Nerve conduction, folate and B12 status were divided into tertiles. Results: Age was 70-78y (57% women). 62.9%, 10.7% and 26.4% were classified as having B12 adequacy (w>-0.5), transitional status (-1.5< w<-0.5) and deficiency (w<-1.5) respectively, while 15.1% presented high folate (>45.3 nmol/L). Nerve conduction velocity of the right peroneus nerve positively correlated with B12 status (r=0.21, p<0.05). In the highest tertile of both B12 (w) and folate only 6% were in lowest tertile of sural nerve conduction vs. 31.5% (p<0.001) with low B12 and high folate. In the highest tertile of both B12 (w) and folate 25% were in lowest tertile of peroneal nerve conduction velocity as compared with 63.2% with low B12 and high folate (p<0.001). Conclusions: Elderly with both high B12 and folate status were less likely to have poor sensory peripheral nerve conduction than those with low B12 and high folate.

Manifestaciones neuropsiquiátricas y cognitivas en demencia frontotemporal y esclerosis lateral amiotrófica: dos polos de una entidad común / Overlapping features of frontotemporal dementia and amyotrophic lateral sclerosis

Recent genetic and neuropathologic advances support the concept that frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are overlapping multisystem disorders. While 10-15% of ALS patients fulfil criteria for FTD, features of motor neuron disease appear in approximately 15% of FTD patients, during the evolution of the disease. This overlap has been reinforced by the discovery of Transactive Response DNA Binding Protein 43 kDa (TDP43) inclusions as the main neuropathologic finding in the majority of ALS cases and almost a half of FTD cases. Also, an expansion in the intron of C9ORF72 (chromosome 9p21) has been identified in families affected by ALS, ALS-FTD and FTD. This review provides an update on the recent genetic and neuropathologic findings of ALS and FTD and a characterization of their clinical presentation forms, based on the current diagnostic criteria. Finally it underscores the importance of having a national registry of patients with ALS and FTD, to provide an earlier diagnosis and a multidisciplinary care.

Déficit de vitamina B-12 en adultos mayores: ¿Un problema de salud pública en Chile? / Prevalence of vitamin B-12 deficiency in older adults

Background: There is a correlation between aging and the decrease of plasma levels of vitamin B-12. Aim: To determine the prevalence of vitamin B-12 and folate deficiency and its hematological impact among older adults (AM). Material and Methods: Cross-sectional study, in 1028 subjects aged 65 to 87years, living in community and evaluated between 2005 and 2008. Percentile distribution of vitamin B-12, folate, hemoglobin, packed red cell volume and mean cell volume by gender and age were analyzed. Deficiency was defined as vitamin B-12 levels < 148 pmol/L, marginal deficiency as vitamin B-12 levels < 221 pmol/L, anemia was defined as a hemoglobin < 13 and 12 g/dL among men and women, respectively. Results: The prevalence of vitamin B-12 deficiency was 12 percent and the figure for marginal deficiency was 25.4 percent. Males were more affected than females (p < 0.001). The frequency of anemia was 8.6 percento, and was higher among women (p = 0.004). Conclusions: There is a high prevalence of full blown and marginal deficit of vitamin B-12 among the elderly. This deficiency should be considered for correction through public nutrition policies.

Afasia subcortical por lesión vascular del cuerpo estriado / Subcortical aphasia due to vascular lesion of striatum body

Se presenta cuatro pacientes con lesión vascular de núcleos estriados izquierdos (dos infartos y dos hemorragias) que presentaron una alteración del habla caracterizada por mutismo inicial, seguido de lenguaje no fluido, disártrico, hipofónico, con parafasias fonémicas y semánticas, sin compromiso importante de la comprensión y con buena repetición y nominación. Los pacientes presentaron un curso fluctuante con tendencia a la mejoría en un período de meses. El cuadro corresponde a las afasias descritas en relación a los ganglios basales. Se discute la participación del cuerpo estriado en el lenguaje en relación al tálamo y las áreas corticales asociadas con el habla