Predictors of Mechanical Ventilation in Guillain-Barré Syndrome with Axonal Subtypes.

BACKGROUND: The early clinical predictors of respiratory failure in Latin Americans with Guillain-Barré syndrome (GBS) have scarcely been studied. This is of particular importance since Latin America has a high frequency of axonal GBS variants that may imply a worse prognosis. METHODS: We studied 86 Mexican patients with GBS admitted to the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, a referral center of Mexico City, to describe predictors of invasive mechanical ventilation (IMV). RESULTS: The median age was 40 years (interquartile range: 26-53.5), with 60.5% men (male-to-female ratio: 1.53). Most patients (65%) had an infectious antecedent (40.6% gastrointestinal). At admission, 38% of patients had a Medical Research Council (MRC) sum score <30. Axonal subtypes predominated (60.5%), with acute motor axonal neuropathy being the most prevalent (34.9%), followed by acute inflammatory demyelinating polyneuropathy (32.6%), acute motor sensory axonal neuropathy (AMSAN) (25.6%), and Fisher syndrome (7%). Notably, 15.1% had onset in upper limbs, 75.6% dysautonomia, and 73.3% pain. In all, 86% received either IVIg (9.3%) or plasma exchange (74.4%). IMV was required in 39.5% patients (72.7% in AMSAN). A multivariate model without including published prognostic scores yielded the time since onset to admission <15 days, axonal variants, MRC sum score <30, and bulbar weakness as independent predictors of IMV. The model including grading scales yielded lower limbs onset, Erasmus GBS respiratory insufficiency score (EGRIS) >4, and dysautonomia as predictors. CONCLUSION: These results suggest that EGRIS is a good prognosticator of IMV in GBS patients with a predominance of axonal electrophysiological subtypes, but other early clinical data should also be considered.

Clinical and neurophysiological description of patients with POEMS syndrome.

INTRODUCTION: POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a monoclonal gammopathy with polyneuropathy as a mandatory criterion. OBJECTIVE: To describe potential associations between clinical expression and electrodiagnostic patterns in POEMS syndrome. METHOD: Observational, retrospective, cross-sectional study of cases cared for in a referral center, diagnosed with POEMS syndrome from 2009 to 2019. RESULTS: Eleven patients (8 men) were analyzed. Median age at diagnosis was 40 years (range: 31-51; mean: 37.19 ± 15.67 years). Mean latency at diagnosis was 9.7 ± 8.37 months. In all subjects, initial clinical manifestation was polyneuropathy. Most patients had an axonal pattern (n = 5), followed by demyelinating (n = 4) and mixed patterns (n = 2). Monoclonal gammopathy was observed in all (6 l and 5 k cases; immunoglobulin [Ig] G: 72 %; IgA: 18 %; IgM: 9 %). Medical Research Council sum score was lower in the axonal pattern (median: 37.00 vs. 45.5; p = 0.024). There were no differences in systemic involvement between electrophysiological patterns. CONCLUSION: Electrophysiological patterns are unlikely to have a clear extra-neurological clinical correspondence; however, this will have to be definitively proven with a larger sample size.

INTRODUCCIÓN: El síndrome POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) es una gammapatía monoclonal con polineuropatía como criterio obligatorio. OBJETIVO: Describir las potenciales asociaciones entre la expresión clínica y los patrones de electrodiagnóstico en el síndrome POEMS. MÉTODO: Estudio observacional, retrospectivo y transversal de los casos atendidos en un centro de referencia con diagnóstico de síndrome de POEMS de 2009 a 2019. RESULTADOS: Se analizó a 11 pacientes (8 hombres). La mediana de la edad al diagnóstico fue de 40 años (rango: 31-51, media: 37.19 ± 15.67 años). La latencia media al diagnóstico fue de 9.7 ± 8.37 meses. En todos la manifestación clínica inicial fue la polineuropatía. La mayoría de los pacientes presentaron un patrón axonal (n = 5), seguido del desmielinizante (n = 4) y mixto (n = 2). La gammapatía monoclonal se observó en todos (6 casos l y 5 k, inmunoglobulina [Ig] G: 72%, IgA: 18%, IgM: 9%). El Medical Research Council sum score fue menor en el patrón axonal (medianas: 37.00 vs. 45.5, p = 0.024). No se presentaron diferencias en la afección sistémica entre patrones electrofisiológicos. CONCLUSIÓN: Es poco probable que los patrones electrofisiológicos tengan una correspondencia clínica extraneurológica clara, sin embargo, esto deberá probarse de forma definitiva con un mayor tamaño de muestra.

Randomized Trial of Thymectomy in Myasthenia Gravis.

BACKGROUND: Thymectomy has been a mainstay in the treatment of myasthenia gravis, but there is no conclusive evidence of its benefit. We conducted a multicenter, randomized trial comparing thymectomy plus prednisone with prednisone alone. METHODS: We compared extended transsternal thymectomy plus alternate-day prednisone with alternate-day prednisone alone. Patients 18 to 65 years of age who had generalized nonthymomatous myasthenia gravis with a disease duration of less than 5 years were included if they had Myasthenia Gravis Foundation of America clinical class II to IV disease (on a scale from I to V, with higher classes indicating more severe disease) and elevated circulating concentrations of acetylcholine-receptor antibody. The primary outcomes were the time-weighted average Quantitative Myasthenia Gravis score (on a scale from 0 to 39, with higher scores indicating more severe disease) over a 3-year period, as assessed by means of blinded rating, and the time-weighted average required dose of prednisone over a 3-year period. RESULTS: A total of 126 patients underwent randomization between 2006 and 2012 at 36 sites. Patients who underwent thymectomy had a lower time-weighted average Quantitative Myasthenia Gravis score over a 3-year period than those who received prednisone alone (6.15 vs. 8.99, P<0.001); patients in the thymectomy group also had a lower average requirement for alternate-day prednisone (44 mg vs. 60 mg, P<0.001). Fewer patients in the thymectomy group than in the prednisone-only group required immunosuppression with azathioprine (17% vs. 48%, P<0.001) or were hospitalized for exacerbations (9% vs. 37%, P<0.001). The number of patients with treatment-associated complications did not differ significantly between groups (P=0.73), but patients in the thymectomy group had fewer treatment-associated symptoms related to immunosuppressive medications (P<0.001) and lower distress levels related to symptoms (P=0.003). CONCLUSIONS: Thymectomy improved clinical outcomes over a 3-year period in patients with nonthymomatous myasthenia gravis. (Funded by the National Institute of Neurological Disorders and Stroke and others; MGTX ClinicalTrials.gov number, NCT00294658.).

Enfermedad carotídea aterosclerosa y enfermedad de sustancia blanca en sujetos sin historia de infarto cerebral o isquemia cerebral transitoria.

INTRODUCTION: Atherosclerotic carotid artery disease (CAD) is a major risk factor for cerebrovascular disease. OBJECTIVE: To analyze the association of major vascular risk factors with atherosclerotic CAD and white matter disease (WMD) in patients without a history of ischemic stroke. METHOD: Risk factors were assessed with carotid examination using Doppler duplex ultrasound. Cases with a history cerebral infarction or transient ischemic attack were not included. Subjects had brain magnetic resonance imaging scans available and those with large-artery ischemic lesions were excluded. Multivariate models were constructed for the prediction of atherosclerotic CAD, significant carotid stenosis, atheroma burden and WMD. RESULTS: One-hundred and forty-five subjects were assessed (60.7% were females, mean age was 73 years). Atherosclerotic CAD was documented in 54.5%, carotid stenosis ≥ 50% in 9.0%, > 6 atheroma plaques in 7.6%, and periventricular or subcortical WMD in 28.3% (20.6% had atherosclerotic CAD and WMD concurrently). Risk factors independently associated with atherosclerotic CAD were age and hypertension; hypertension was associated with ≥ 50% carotid stenosis; age was associated with > 6 atheroma plaques; and age, diabetes and hypertension were associated with WMD. Obesity was not associated with any of the analyzed independent variables. CONCLUSIONS: In asymptomatic subjects without a history of ischemic stroke, age and hypertension were the most important risk factors for macrovascular disease. Diabetes mellitus was associated with microvascular disease. Obesity alone was not a major determinant of CAD or WMD.

INTRODUCCIÓN: La enfermedad carotídea aterosclerosa (ECA) es un factor de riesgo importante para enfermedad vascular cerebral. OBJETIVO: Analizar la asociación entre factores de riesgo vascular mayores con ECA y leucopatía cerebral en pacientes sin historia de ictus isquémico. MÉTODO: Se evaluaron factores de riesgo en sujetos con exploración de carótidas mediante ultrasonografía Doppler dúplex. No se incluyeron casos con historia de infarto cerebral o ataque isquémico transitorio. Los sujetos contaron con resonancia magnética cerebral y se excluyeron aquellos con lesiones isquémicas de grandes vasos. Se construyeron modelos multivariable para la predicción de ECA, estenosis carotídea significativa, carga de ateromas y leucopatía cerebral. RESULTADOS: Se estudiaron 145 sujetos (60.7 % mujeres, edad de 73 años). Se documentó ECA en 54.5 %, estenosis carotídea ≥ 50 % en 9 %, carga de placas de ateroma > 6 en 7.6 % y leucopatía periventricular o subcortical en 28.3 % (20.6 % tenían concurrentemente ECA y leucopatía). Los factores asociados independientemente con ECA fueron edad e hipertensión; con estenosis ≥ 50 %, hipertensión; con cargas de ateromas > 6 placas, edad; con leucopatía, edad, diabetes e hipertensión. La obesidad no se asoció con las variables independientes analizadas. CONCLUSIONES: En los sujetos asintomáticos sin historia de ictus isquémico, la edad y la hipertensión fueron los factores de riesgo más importantes para enfermedad macrovascular. La diabetes mellitus se asoció con enfermedad microvascular. La obesidad por sí sola no fue un determinante mayor de ECA o leucopatía cerebral.

[Myasthenia gravis in adults of institutions pertaining to the Mexican public health system: an analysis of hospital discharges during 2010]. / Miastenia gravis (MG) en adultos de instituciones pertenecientes al sistema público sanitario mexicano: un análisis de egresos hospitalarios durante el año 2010.

INTRODUCTION: Epidemiological studies on myasthenia gravis (MG) in Mexico is mainly derived from experiences in referral centers. OBJECTIVE: To describe the epidemiological characteristics of hospital discharges during 2010 with the diagnosis of MG in adults hospitalized in the Mexican public health system. METHODS: We consulted the database of hospital discharges during 2010 of the National Health Information System (Ministry of Health, IMSS, IMSS oportunidades, ISSSTE, PEMEX, and the Ministry of Defense). The MG records were identified by the code G70.0 of the International Classification of Diseases 10th revision. RESULTS: During 2010 there were 5,314,132 hospital discharges (4,254,312 adults). Among them, 587 (0.01%) were adults with MG (median age: 47 years, 60% women). Women with MG were significantly younger than men (median age: 37 vs. 54 years, respectively; p < 0.001). The median hospital stay was six days. The case fatality rate was 3.4%, without gender differences. Age was associated with the probability of death. CONCLUSIONS: We confirmed the bimodal age-gender distribution in MG. The in-hospital case fatality rate in Mexico is consistent with recent reports around the world.

Assessment of emotional distress in chronic kidney disease patients and kidney transplant recipients.

OBJECTIVE: To assess the presence of emotional distress in patients with chronic kidney disease (CKD), and the effect of kidney transplant on these symptoms. MATERIAL AND METHODS: This was a two-part study. Part one was cross-sectional, observational, and descriptive, where 75 patients with CKD were evaluated for emotional distress with the Hospital Anxiety and Depression Scale (HAD) and the Symptom Checklist 90 (SCL-90). In part two, we longitudinally followed 19% of the study cohort to examine symptomatological changes after their kidney transplantation. RESULTS: The results of the HAD indicated that 30.7% of the study cohort with End-Stage Renal Disease (ESRD) showed anxious symptoms, and 25.3% showed depressive symptoms. The change in the HAD total score before and after kidney transplant was not significant. However, a significant decrease in total score on the SCL-90 was observed before and after transplantation. CONCLUSION: Improvement on emotional distress was found after kidney transplantation.

Neurologic manifestations in hospitalized patients with COVID-19 in Mexico City.

BACKGROUND: The coronavirus disease 2019 (COVID-19) is a systemic entity that frequently implies neurologic features at presentation and complications during the disease course. We aimed to describe the characteristics and predictors for developing in-hospital neurologic manifestations in a large cohort of hospitalized patients with COVID-19 in Mexico City. METHODS: We analyzed records from consecutive adult patients hospitalized from March 15 to June 30, 2020, with moderate to severe COVID-19 confirmed by reverse transcription real-time polymerase chain reaction (rtRT-PCR) for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Neurologic syndromes were actively searched by a standardized structured questionnaire and physical examination, confirmed by neuroimaging, neurophysiology of laboratory analyses, as applicable. RESULTS: We studied 1,072 cases (65% men, mean age 53.2±13 years), 71 patients had pre-existing neurologic diseases (diabetic neuropathy: 17, epilepsy: 15, history of ischemic stroke: eight, migraine: six, multiple sclerosis: one, Parkinson disease: one), and 163 (15.2%) developed a new neurologic complication. Headache (41.7%), myalgia (38.5%), dysgeusia (8%), and anosmia (7%) were the most common neurologic symptoms at hospital presentation. Delirium (13.1%), objective limb weakness (5.1%), and delayed recovery of mental status after sedation withdrawal (2.5%), were the most common new neurologic syndromes. Age, headache at presentation, preexisting neurologic disease, invasive mechanical ventilation, and neutrophil/lymphocyte ratio ≥9 were independent predictors of new in-hospital neurologic complications. CONCLUSIONS: Even after excluding initial clinical features and pre-existing comorbidities, new neurologic complications in hospitalized patients with COVID-19 are frequent and can be predicted from clinical information at hospital admission.

Hypothalamic abnormalities and Parkinsonism associated with H1N1 influenza infection.

OBJECTIVE: To describe a case of a young adult with severe H1N1 influenza illness associated with hypothalamic abnormalities and post-influenza parkinsonism. DESIGN: Case report. PATIENT: A 22-year-old woman with H1N1 influenza infection developed encephalopathy followed by diverse hypothalamic dysfunction manifestations, sleeplessness, and persistent parkinsonian features. RESULTS: CSF analysis, brain imaging and EEG ruled out hypoxic brain injury or other illnesses. CONCLUSIONS: A number of viruses have been associated with both acute and chronic parkinsonism. A link between parkinsonism and influenza viruses is somewhat controversial. This is the first reported case of parkinsonism following an H1N1 influenza infection.

Association between body mass index and migraine.

OBJECTIVE: To explore the prevalence of overweight and obesity in patients with migraine. BACKGROUND: Previous studies support the concept that obesity is an exacerbating factor for migraine. Also, some studies have found an increased frequency of obesity and overweight in migraine patients compared to the normal population. METHODS: We studied 1,371 patients with migraine and 612 controls. The migraine population was matched by gender with a healthy control group. RESULTS: Mean age of patients with migraine was 38.0 +/- 13.3 years and in the controls it was 34.8 +/- 12.1 years. The percentage of females in both groups was similar (migraine 81.6% vs. control 83.3%, p = 0.40). The distribution of body mass index (BMI) in migraine patients and controls was as follows: underweight patients (BMI <18.5) 3.1% migraine versus controls 1.5%; normal (BMI 18.5-24.9) 44.8% migraine versus controls 47.1%; overweight (BMI 25-29.9) 38.3% migraine versus controls 33.7%; obese (BMI 30-34.5) 10.3% migraine versus controls 13.6%; morbidly obese (BMI 35) 3.4% migraine versus controls 4.2%. Overweight and obesity in migraine patients versus controls were statistically significant. No association was found between the disability and severity of migraine and BMI. CONCLUSIONS: This study did not find associations between severity or disability of migraine and BMI.

Clinical characteristics and outcomes of the meningitides in systemic lupus erythematosus.

BACKGROUND: The meningitides are rare but well-identified complications in patients with systemic lupus erythematosus (SLE). AIMS: To determine the clinical characteristics, risk factors, prevalence and outcomes of the meningitides (septic and aseptic) in patients with SLE. PATIENTS AND METHODS: From January 1988 to December 2006, we identified patients with SLE and septic or aseptic meningitis. RESULTS: We identified 25 episodes of meningitis in 23 patients with SLE, from a total of 1,411 SLE patients (1.63%); in 15 out of 25 episodes, a microorganism was identified. Mycobacterium tuberculosis, Listeria monocytogenes and Criptococcus neoformans represented the main microorganisms. In 10 episodes, aseptic meningitis was diagnosed. Lymphopenia, steroid use, chronic damage and systemic activity of SLE were frequent in both kinds of meningitis. Although the clinical presentation did not differ significantly, patients with septic meningitis had more residual neurological deficits (p = 0.04). CONCLUSIONS: Meningitis was observed in about 1.6% of the patients with SLE; in 40% of the cases, no microorganism could be isolated. A residual neurological deficit was more common in patients with septic meningitis.

Acute neurolupus manifested by seizures is associated with high frequency of abnormal cerebral blood flow velocities.

BACKGROUND: Systemic lupus erythematosus may present with a wide variety of neurological manifestations, which could be related to the presence of vasculopathy and microembolic signals (MES). OBJECTIVES: We aimed to determine the prevalence of MES and altered blood flow velocities (BFVs) by transcranial Doppler (TCD) in patients with acute neuropsychiatric lupus erythematosus (NPLE). METHODS: Fifteen consecutive patients with acute NPLE (cases) and 30 patients with systemic lupus erythematosus but without acute NPLE (controls) underwent TCD testing for comparison purposes. RESULTS: We found higher mean BFVs in cases compared with controls in the left (100 vs. 73.5 cm/s, p = 0.018) and in the right (96 vs. 70 cm/s, p = 0.013) middle cerebral arteries. The proportion of MES in both groups was the same (13%). Abnormal TCDs were more frequent in patients with acute NPLE, 67 versus 17% (p = 0.001), and occurred more often in patients who presented seizures. CONCLUSIONS: The frequency of MES was the same in both groups; however, patients with seizures due to acute NPLE usually present with higher BFVs than controls. This could be a marker of diffuse acute cerebral vasculopathy.

Clinical description of seizures in patients with systemic lupus erythematosus.

OBJECTIVE: To evaluate the frequency of and risk factors for epileptic seizures in patients with systemic lupus erythematosus (SLE) in a large cohort series. METHODS: One thousand two hundred patients with SLE were analyzed. The type and frequency of risk factors for seizures associated with SLE were studied and compared with two other series reported in the literature. RESULTS: One hundred and forty-two patients had seizures. Seventy-five patients were studied with a mean follow-up of 5 years from the first seizure episode. Fifty-eight (77%) patients had tonic-clonic seizures, 9 (12%) complex partial seizures (PS), 5 (7%) simple partial motor seizures and 3 (4%) secondary tonic-clonic seizures. In 41 (54%) patients, the seizures occurred within the first year of the SLE diagnosis. Recurrence occurred in 40 (53%) patients, and was associated with PS in 14 (35%; p = 0.006) and time of seizures with SLE onset in 5 (12.5%; p = 0.05). Less than one third of the patients had positive antiphospholipid antibodies. A concurrent infection was present in 16 (21%) patients. CONCLUSIONS: Epileptic seizures were more common during the first year after SLE diagnosis. Neither infection nor antiphospholipid syndrome was associated with the occurrence of seizures.

Clinical description of intracranial hemorrhage associated with bleeding disorders.

BACKGROUND: Intracerebral hemorrhage (ICH) is an unusual but serious complication of bleeding disorders. ICH is believed to follow thrombocytopenia, alterations in coagulation, and vascular fragility. Information regarding its distribution is nonconclusive, and the mechanism of bleeding is not fully understood. The aim of this study was to examine the clinical and neuroimaging features of ICH in patients with bleeding disorders to predict risk factors for this condition. METHODS: All cases of ICH diagnosed from 1987 to 2004 were retrospectively identified using the centralized database of our institution. Cases were included whenever ICH was caused by a primary hematologic disorder. The clinical characteristics, neuroimages, and outcome were analyzed. RESULTS: A total of 31 patients were identified. ICH was the initial presentation of the bleeding disorder in 9 patients. Overall, 71% had systemic bleeding concurrent to the ICH. All patients had altered mental status. In 45.2% of the patients simultaneous intracranial hemorrhages were found. Eight patients had recurrent ICH. Severe thrombocytopenia (platelet count < 10,000/mm(3)) was present in 41% and very low platelets (

Respiratory and non respiratory oscillations of the skin blood flow: a window to the function of the sympathetic fibers to the skin blood vessels.

OBJECTIVE OF THE STUDY: The skin blood flow (SBF) has been known to oscillate in frequency and amplitude. The nature and type of these oscillations have remained obscure. We studied the oscillations of the SBF in frequency and amplitude with non invasive techniques during normal breathing at rest and compared it to the oscillations during rhythmic paced breathing at 6 cycles per minute. SUBJECTS AND METHODS: Thirty healthy subjects were studied under normothermic conditions. The following variables were recorded: 1) EKG signal; 2) SBF signal given by an infrared photoplethysmograph; 3) respiratory movements (RM). A correlation of the frequency of the respiration, the SBF and the EKG was made. The variability of the amplitudes of the SBF, RR intervals and pulse intervals was analyzed in the time domain and with spectral analysis using Fourier analysis. RESULTS: We found no clear respiratory modulation of the amplitude of the SBF during natural breathing at rest. With default breathing there was a low frequency oscillations (LF 0.04 to 0.15 Hz) modulation of the amplitude of the SBF that was non respiratory in nature. During rhythmic breathing at 0.1 Hz there was a strong modulation at LF of the SBF with a typical waxing and waning appearance, decreasing in amplitude during the tachycardia period and increasing in amplitude during the bradycardia period. CONCLUSIONS: Under normothermic conditions there is a consistent variability of the frequency and amplitude of the SBF with normal and rhythmic breathing. While breathing at rest the modulation of SBF amplitude was clearly seen at LF and non respiratory related. With rhythmic breathing there is a strong modulation of amplitude and frequency at the respiratory frequency.

Efficacy of oral L-ornithine-L-aspartate in cirrhotic patients with hyperammonemic hepatic encephalopathy. Results of a randomized, lactulose-controlled study.

Despite steady progress in therapeutics of liver disease, portal systemic encephalopathy remains to be a great challenge for clinicians because of the heterogeneity of neuropsychiatric symptoms, multiple risk factors and complexity on achieving a sustained response. We aimed to evaluate the efficacy of L-Ornithin, L-Aspartate versus lactulose in Mexican patients with hyperammonemic hepatic encephalopathy. A total of 20 patients were randomly allocated to receive either lactulose(n = 10) or L-ornithine - L-aspartate (n = 10) for 2 weeks. At baseline, patients of both groups were comparable in age (64 +/- 7 versus 60 +/- 6) and degree of hepatic failure according to the Child-Pugh scale (9.2 +/- 1.3 versus 9.2 +/- 1.1). A significant decrease in ammonia levels was observed both in the lactulose group (120.4 +/- 8.1 versus 91.4 +/- 10, p < 0.05) and in the LOLA group (141.6 +/- 9.1 versus 96.9 +/- 9.3, p < 0.05). Moreover, in patients who received LOLA a significant improvement was observed in mental status (1.0 +/- 0.14 versus 0.4 +/- 0.16, p < 0.05), Number Connection Test (184 +/- 43 versus 88 +/- 7, p < 0.05), asterixis (14.6 +/- 2.8 versus 6.7 +/- 1.5, p < 0.05), as well as EEG findings (6.8 +/- 0.6 versus 8.1 +/- 0.2 cycles per second, p < 0.05). Compliance with study medications was similar between the lactulose group (94%) and the LOLA group (100%). No serious adverse events were reported in the two groups; however, in the lactulose group an increase in the number of weekly defecations was reported, as well as a higher incidence of abdominal pain or flatulence. Finally, both patient groups reported an improvement in the Visual Analogue Scale for EuroQol index (51.1 +/- 24.1 versus 61.5 +/- 15.8, p < 0.05, in the lactulose group; 56.5 +/- 24.5 versus 70 +/- 19.4, p < 0.05, in the LOLA group). In conclusion, oral administration of lactulose or L-ornithine - L-aspartate to Mexican patients with cirrhosis and hyperammonemic encephalopathy significantly reduced serum ammonia levels in study groups and additionally improved mental status parameters, number connection test, asterixis scores, and EEG activity in the group receiving L-ornithine-L-aspartate.

[Practice guidelines for neuropathic pain management]. / Parámetros de práctica para el manejo del dolor neuropático.

UNLABELLED: Neuropathic pain (NP) is a heterogeneous entity with wide diversity of symptoms. Despite the controversies regarding its definition and classification, which difficult its epidemiology, it has been estimated that 4 million people, in USA develop NP. OBJECTIVE: A task force was created to generate a series of recommendations which facilitate the decision making and therapeutic approach of this kind of pain. METHOD: A search of medical literature was made in different electronic data bases (MEDLINE, EMBASE, COCHRANE); after this search we conducted three work-sessions and evaluated the evidence regarding the diagnosis and treatment of pain in painful diabetic poli-neuropathy, post-herpetic neuralgia, and trigeminal neuralgia were evaluated. RESULTS: We found 329 documents for further analysis, and with the aid of the literature results we generate this practice guidelines.

Intermittent hypoxemia and sleep fragmentation: associations with daytime alertness in obese sleep apnea patients living at moderate altitude.

BACKGROUND: Although obstructive sleep apnea (OSA) has long been associated with daytime sleepiness, far less is known about its association with the ability to remain awake. The aim of this study was to examine the relative importance of inter-correlated measures of OSA severity (eg, various indices of oxygen saturation and sleep fragmentation) in the ability to stay alert as measured objectively by the Maintenance of Wakefulness Test (MWT), defined by a mean sleep latency of ≥12 min. METHODS: Seventy-eight obese women and men of similar age and body mass index living at altitude (Mexico City) underwent standard polysomnography, MWT, and completed validated sleep-related questionnaires. RESULTS: Men had more severe sleep apnea than women (p = 0.002) and were also less alert on MWT (p = 0.022). Logistic regression models indicated that measures of desaturation consistently predicted MWT-defined alertness, whereas varied measures of sleep fragmentation did not. Nearly a third of the variance (r(2) = 0.304) in MWT-defined alertness was accounted for by the number of desaturations per hour of sleep (p = 0.003), which is considerably higher than other studies have reported in different populations. CONCLUSION: The ability to remain awake in obese patients is best accounted for by hypoxemia rather than sleep fragmentation. Whether the size of this effect reflects differences in the population under study (eg, extent of obesity, racial background, residence at moderate altitude) and/or is a function of the measurement of alertness with the MWT remains uncertain.

Effect of bariatric surgery on obstructive sleep apnea and hypopnea syndrome, electrocardiogram, and pulmonary arterial pressure.

BACKGROUND: We evaluated the impact of surgically-induced weight loss on Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS), electrocardiographic changes, pulmonary arterial pressure and daytime sleepiness in morbidly obese patients. METHODS: 16 women and 13 men (n=29) underwent bariatric surgery in a 3-year period. The following tests were performed before and 1 year after surgery: nocturnal polysomnography, daytime Multiple Sleep Latency Test (MSLT), and echocardiogram. RESULTS: Mean age was 37.9+/-11 years (range 20-56). Preoperative body mass index was 56.5+/-12.3 kg/m(2) and it was 39.2+/-8.5 kg/m(2) at 13.7+/-6.6 months follow-up. Performed surgical procedures included: vertical banded gastroplasty in 6, Roux-en-Y gastric bypass in 12, and Distal Roux-en-Y gastric bypass in 11. Weight loss induced by surgery eliminated OSAHS in 46% of obese patients with an important improvement in oxygen saturation. Neck, thorax, waist and hip circumferences decreased significantly after surgical intervention but only neck circumference correlated significantly with the apnea/hypopnea index (Spearman rho=0.63, P <0.0001). Electrocardiographic abnormalities were present in 9 patients (31%) before surgery (sinus arrhythmia, ventricular arrhythmias, and sinus arrest). The number of electrocardiographic abnormalities decreased after surgery but new abnormalities appeared in some patients. Systolic pulmonary arterial pressure significantly decreased in the group of patients in whom OSAHS disappeared after surgery. Daytime sleepiness persisted after surgery in most patients. CONCLUSION: Bariatric surgery effectively reduces respiratory disturbances during sleep and improves pulmonary hypertension. Electro cardiographic abnormalities change after surgery. Daytime sleepiness appeared not to be related to respiratory disturbances during sleep.

Thymectomy in myasthenia gravis: response, complications, and associated conditions.

BACKGROUND: Thymectomy is considered the most effective treatment for achieving sustained improvement as well as remission in patients with myasthenia gravis (MG), and most neurologists favor the use of this procedure. The main focus of many current studies is to determine response-predicting factors. METHODS: Clinical records of 152 patients with an established diagnosis of MG who underwent thymectomy at our institution were reviewed. The purpose was to evaluate outcome of surgical management for MG and prognostic factors that influence that outcome. RESULTS: The majority of patients were women (119 of 152); mean age was 32.10 +/- 14.42 years, while time elapsed from diagnosis to surgery was 20.67 +/- 19.7 months. Transsternal thymectomy was performed on 113 patients and transcervical on 39. Forty percent of patients achieved remission and 28% showed improvement; with this, a good response to thymectomy was seen in 68% of patients (n = 103). The most important variables associated with remission were <60 years of age, <2 years of preoperative symptoms, and use of pyridostigmine at low doses. Factors related with poor response were >60 years of age, preoperative Osserman stage other than II, use of high doses of pyridostigmine, use of corticosteroids, and presence of thymic atrophy or thymoma in histopathologic analyses. There was no mortality, although 20 patients (13%) presented complications. CONCLUSIONS: Mexican patients with MG undergoing thymectomies show improvement and remission rates similar to those reported by other studies. Age, length of symptoms, thymic pathology, and medications appear to be predictors of response to thymectomy for MG.