Factors Predicting Prolonged Mechanical Ventilation in Guillain-Barré Syndrome.

BACKGROUND: Up to 30% of patients with Guillain-Barré syndrome require mechanical ventilation and 5% die due to acute complications of mechanical ventilation. There is a considerable group of patients that will need prolonged mechanical ventilation (considered as >14 days) and should be considered for early tracheostomy. The objective of this study is to identify risk factors for prolonged mechanical ventilation. METHODS: We prospectively analyzed patients with Guillain-Barré diagnosis with versus without prolonged mechanical ventilation. We considered clinical and electrophysiological characteristics and analyzed factors associated with prolonged mechanical ventilation. RESULTS: Three hundred and three patients were included; 29% required mechanical ventilation. When comparing the groups, patients with prolonged invasive mechanical ventilation (IMV) have a lower score on the Medical Research Council score (19.5 ± 16.2 vs 27.4 ± 17.5, p = 0.03) and a higher frequency of dysautonomia (42.3% vs 19.4%, p = 0.037), as well as lower amplitudes of the distal compound muscle action potential (CMAP) of the median nerve [0.37 (RIQ 0.07-2.25) vs. 3.9 (RIQ1.2-6.4), p = <0.001] and ulnar nerve [0.37 (RIQ0.0-3.72) vs 1.5 (RIQ0.3-6.6), p = <0.001], and higher frequency of severe axonal damage in these nerves (distal CMAP ≤ 1.0 mV). Through binary logistic regression, severe axonal degeneration of the median nerve is an independent risk factor for prolonged IMV OR 4.9 (95%CI 1.1-21.5) p = 0.03, AUC of 0.774, (95%CI 0.66-0.88), p = < 0.001. CONCLUSIONS: Severe median nerve damage is an independent risk factor for prolonged mechanical ventilation.

Prognostic Implications of Early Albuminocytological Dissociation in Guillain-Barré Syndrome.

BACKGROUND: Half of Guillain-Barré syndrome (GBS) present elevated cerebrospinal fluid (CSF) protein levels within 1 week since symptom onset and 80% within 2 weeks. Our objective was to determine the clinical and prognostic implication of albuminocytological dissociation in early GBS. METHODS: An ambispective cohort study was conducted. Good outcome was considered if the patient was able to walk unaided (Guillain-Barré disability score [GDS] ≤ 2 points) at 3-month follow-up. Patients were classified into two groups: with and without albuminocytological dissociation; we compared clinical and paraclinic characteristics between the groups. We analyzed clinical and electrophysiological factors related to presenting early dissociation through a multivariate model. RESULTS: We included 240 patients who fulfilled Asbury criteria for GBS. On further selection, only 94 patients fulfilled inclusion. Mean age was 45.94 ± 17.1 years and 67% were male. Median time from symptom onset to admission was 5 days (IQR 3-6). Regarding albuminocytological dissociation and electrophysiological variants, we found a significant difference: acute inflammatory demyelinating polyneuropathy (AIDP) [60.6% vs 26.2%, p = 0.002], acute motor axonal neuropathy (AMAN) [21.2% vs 49.1%, p = 0.009] and acute motor sensory axonal neuropathy (AMSAN) [12.1% vs 1.6%, p = 0.05]. We did not observe significant differences in recovery of independent walking in short term between both groups. The presence of conduction block in any variant (OR 3.21, 95% CI 1.12-9.16, p = 0.02) and absence of sural registration (OR 5.69, 95% CI 1.48-21.83, p = 0.011) were independent factors related to early dissociation. CONCLUSIONS: Early dissociation (<7 days) is not associated with any particular clinical feature or unfavorable outcome. It is more common to see in AIDP rather than axonal variants.

Incidence of Guillain-Barré syndrome following SARS-CoV-2 immunization: Analysis of a nationwide registry of recipients of 81 million doses of seven vaccines.

BACKGROUND AND PURPOSE: Information on Guillain-Barré syndrome (GBS) as an adverse event following immunization (AEFI) against SARS-CoV-2 remains scarce. We aimed to report GBS incidence as an AEFI among adult (≥18 years) recipients of 81,842,426 doses of seven anti-SARS-CoV-2 vaccines between December 24, 2020, and October 29, 2021, in Mexico. METHODS: Cases were retrospectively collected through passive epidemiological surveillance. The overall observed incidence was calculated according to the total number of administered doses. Vaccines were analyzed individually and by vector as mRNA-based (mRNA-1273 and BNT162b2), adenovirus-vectored (ChAdOx1 nCov-19, rAd26-rAd5, Ad5-nCoV, and Ad26.COV2-S), and inactivated whole-virion-vectored (CoronaVac) vaccines. RESULTS: We identified 97 patients (52 males [53.6%]; median [interquartile range] age 44 [33-60] years), for an overall observed incidence of 1.19/1,000,000 doses (95% confidence interval [CI] 0.97-1.45), with incidence higher among Ad26.COV2-S (3.86/1,000,000 doses, 95% CI 1.50-9.93) and BNT162b2 recipients (1.92/1,00,000 doses, 95% CI 1.36-2.71). The interval (interquartile range) from vaccination to GBS symptom onset was 10 (3-17) days. Preceding diarrhea was reported in 21 patients (21.6%) and mild COVID-19 in four more (4.1%). Only 18 patients were tested for Campylobacter jejuni (positive in 16 [88.9%]). Electrophysiological examinations were performed in 76 patients (78.4%; axonal in 46 [60.5%] and demyelinating in 25 [32.8%]); variants were similar across the platforms. On admission, 91.8% had a GBS disability score ≥3. Seventy-five patients (77.3%) received intravenous immunoglobulin, received seven plasma exchange (7.2%), and 15 (15.5%) were treated conservatively. Ten patients (10.3%) died, and 79.1% of survivors were unable to walk independently. CONCLUSIONS: Guillain-Barré syndrome was an extremely infrequent AEFI against SARS-CoV-2. The protection provided by these vaccines outweighs the risk of developing GBS.

Very low peroneal nerve compound muscle action potential amplitude predicts poor outcome in patients with Guillain-Barré syndrome: a prospective cohort.

INTRODUCTION: Twenty percent of patients with Guillain-Barré syndrome (GBS) have poor outcomes despite proper management. The aim of the study was to characterize electrophysiological factors related to poor outcome in patients with GBS. METHODS: We conducted an observational study from a prospective cohort of 91 patients with GBS in a tertiary healthcare center in Mexico, from 2017 to 2019. Demographics and nerve conduction studies were performed on admission, and a 3-month follow-up for GBS disability score was ensued, allocating patients in good (GBS disability score ≤ 2) and poor outcome (GBS disability score ≥ 3) groups. A logistic regression analysis for independent walk at 3 months was performed. Kaplan-Meier estimator curves for independent walk in very low (< 20% LLN) and low-normal ( ≥20% LLN) peroneal nerve CMAPs are presented. RESULTS: From the 91 GBS patients included, 37 (40.6%) did not regain independent walk at 3 months. Axonal variants were more common in the poor outcome group (31.4% vs 59.4%, p = 0.01) as well as AIDP variants with motor conduction block (6.6% vs 42.4%, p = 0.018). Univariable analysis was statistically significant for very low median, ulnar, tibial, and peroneal CMAP amplitudes in poor outcome patients; however, multivariable analysis was only significant for very low peroneal nerve CMAP amplitude (OR 3.6 [1.1-11.5, p = 0.024]). Conversely, a greater proportion of GBS patients with low-normal CMAPs recovered independent walk at 90 days (75% vs 30%, p < 0.001). CONCLUSION: Severe axonal injury of the peroneal nerve, axonal, and AIDP with motor conduction block variants predicts worse functional outcome regarding independent walk at 3 months.

Guillain-Barré syndrome is infrequent among recipients of the BNT162b2 mRNA COVID-19 vaccine.

Vaccines are the most effective strategy to mitigate the global impact of COVID-19. However, vaccine hesitancy is common, particularly among minorities. Guillain-Barré syndrome (GBS) is the most common autoimmune illness of the peripheral nervous system, occurring at an incidence of 1.1/100,000 worldwide. A causal link between mRNA vaccines and GBS has not been previously evaluated. We analyzed a cohort of 3,890,250 Hispanic/Latinx recipients of the BNT162b2 mRNA vaccine (613,780 of whom had already received both doses) for incident GBS occurring within 30 days from vaccine administration. Seven cases of GBS were detected among first-dose recipients, for an observed incidence of 0.18/100,000 administered doses during the prespecified timeframe of 30 days. No cases were reported after second-dose administration. Our data suggest that, among recipients of the BNT162b2 mRNA vaccine, GBS may occur at the expected community-based rate; however, this should be taken with caution as the current incidence of GBS among the unvaccinated population against COVID-19 is still undetermined. We hope that this preliminary data will increase the public perception of safety toward mRNA-based vaccines and reduce vaccine hesitancy.

Neurologic adverse events among 704,003 first-dose recipients of the BNT162b2 mRNA COVID-19 vaccine in Mexico: A nationwide descriptive study.

mRNA vaccines against SARS-CoV-2 are remarkably effective. Limited information exists about the incidence of adverse events following immunization (AEFI) with their use. We conducted a prospective observational study including data from 704,003 first-doses recipients; 6536 AEFI were reported, of whom 65.1% had at least one neurologic AEFI (non-serious 99.6%). Thirty-three serious events were reported; 17 (51.5%) were neurologic (observed frequency, 2.4/100,000 doses). At the time of writing this report, 16/17 cases had been discharged without deaths. Our data suggest that the BNT162b2 mRNA COVID-19 vaccine is safe; its individual and societal benefits outweigh the low percentage of serious neurologic AEFI. This information should help to dissipate hesitancy towards this new vaccine platform.

[Twelve years of experience in the diagnosis of syphilis in Mexico. Period 2001-2012]. / Doce años de experiencia en el diagnóstico de sífilis en México (periodo 2001-2012).

OBJECTIVE: To determine the incidence of syphilis in Mexico in patients suspected of having the disease or any risk factor. MATERIALS AND METHODS: We performed a descriptive, longitudinal, randomized design study from the period of January 2001 to December 2012, where 51,302 samples were analyzed for syphilis in risk groups. RESULTS: A 39.73% frequency of positive cases was calculated. The estimated average age of detection was 29.08 years. It was found that syphilis affects 47.05% of males and 52.85% of females. The most affected states were Chiapas, Tabasco, and Hidalgo. CONCLUSIONS: Syphilis, despite its decrease in frequency, is an important disease in the major risk groups, so it is vital to take preventive measures to reduce the occurrence of new cases and eliminate cases of congenital syphilis.

Sural nerve involvement in Guillain-Barré syndrome: Clinical and prognostic implications. A prospective cohort.

BACKGROUND: Sural sparing is common in Guillain-Barré syndrome (GBS). However, one third of patients have sural nerve compromise. Its clinical implications associated factors and short-term prognosis are still unknown. The objective of this study is to identify if sural nerve compromise is associated with a worse prognosis and to describe clinical and electrophysiological characteristics in Guillain-Barré syndrome. MATERIALS AND METHODS: We prospectively analyzed patients with Guillain-Barré diagnosis with vs without sural nerve compromise. All patients underwent nerve conduction studies within the first 3 days of hospital admission. Clinical and electrophysiological characteristics were compared between groups. RESULTS: 174 patients were included in this study. Acute inflammatory demyelinating polyneuropathy was the predominant variant (43.7 %). Thirty percent of patients had sural nerve involvement. In the comparative analysis between affected vs unaffected sural groups, age ≥50 years and Guillain-Barré disability score ≥3 demonstrated a statistically significant difference. Regarding short-term recovery period for independent walking, there was no significant difference. In the multivariate analysis, age ≥50 years was identified as independent factors for sural nerve compromise on admission. CONCLUSION: sural nerve compromise occurs in 30 % of patients with GBS and is not associated with a worse functional prognosis. Age ≥50 years was identified as an independent factor for sural nerve compromise.

Psychological and Psychiatric Events Following Immunization with Five Different Vaccines against SARS-CoV-2.

BACKGROUND: Despite the high number of vaccines administered against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) worldwide, the information on the psychological/psychiatric adverse events following immunization (AEFI) with these newly developed vaccines remains scarce. OBJECTIVE: To describe the frequency of psychological/psychiatric symptoms among recipients of five different anti-SARS-CoV-2 vaccines and to explore the factors associated with their development reported in the nationwide Mexican registry of AEFI against SARS-CoV-2. METHODS: Descriptive study of all the psychological/psychiatric symptoms, including anxiety, panic attacks, insomnia, and agitation reported to the Mexican Epidemiological Surveillance System from 21 December 2020 to 27 April 2021, among adult (≥18 years old) recipients of 7,812,845 doses of BNT162b2, ChAdOx1 nCov-19, rAd26-rAd5, Ad5-nCoV, or CoronaVac. The factors associated with their development are determined by multivariate regression analysis. RESULTS: There were 19,163 AEFI reports during the study period; amongst them, 191 (1%) patients had psychological/psychiatric symptoms (median age of 41 years, interquartile range of 32-54; 149 [78%] women) for an observed incidence of 2.44 cases per 100,000 administered doses (95% confidence interval [CI] 2.12-2.82), 72.8% of psychiatric AEFIs were reported among recipients of BNT162b2. The median time from vaccination to symptom onset was 35 min (interquartile range: 10-720). Overall, the most common psychological/psychiatric symptoms were anxiety in 129 (67.5%) patients, panic attacks in 30 (15.7%), insomnia in 25 (13%), and agitation in 11 (5.7%). After adjusting for the confounding factors, the odds for developing psychological/psychiatric symptoms were higher for those concurrently reporting syncope (odds ratio [OR]: 4.73, 95% CI: 1.68-13.33); palpitations (OR: 2.47, 95% CI: 1.65-3.70), and dizziness (OR: 1.59, 95% CI: 1.10-2.28). CONCLUSION: In our population, psychological/psychiatric symptoms were extremely infrequent AEFIs. No severe psychiatric AEFIs were reported. Immunization stress-related responses might explain most of the detected cases.

Prognostic Factors in Elderly Patients With Guillain-Barré Syndrome: Does Age Matter?

INTRODUCTION: Twenty to 40% of Guillain Barré syndrome (GBS) patients will not be able to walk independently despite effective treatment. Older patients carry additional risks for worse outcomes. METHODS: A single center, ambispective cohort study was performed. Only subjects ≥18 years with a 3-month follow-up were included. Elderly patients were considered as a whole if ≥ 60 years. Demographics, CSF and nerve conduction studies were compared. A binomial logistic regression and Kaplan-Meier analyses were carried out to estimate good prognosis (Hugues ≤2) at 3-month follow-up. RESULTS: From 130 patients recruited, 27.6% were elderly adults. They had a more severe disease, higher mEGOS and more cranial nerve involvement. Age ≥70 years, invasive mechanical ventilation and axonal subtype, portrayed an unfavorable 3-month outcome. Further analysis demonstrated an earlier recovery in independent walk at 3 months for patients <70 years. CONCLUSIONS: Elderly patients with GBS have a more severe disease at admission and encounter worse prognosis at 3-month follow-up, especially those above 70 years.

Transient sensory symptoms among first-dose recipients of the BNT162b2 mRNA COVID-19 vaccine: A case-control study.

mRNA-based COVID-19 vaccines are effective; however, persistent vaccine hesitancy is partly due to a misperception of their potential adverse events. Non-specific sensory symptoms (NSSS) following immunization are thought to be mediated by stress-related responses. In this case-control study, we evaluated NSSS from a cohort of 7,812,845 BNT162b2 first-dose recipients, of whom 10,929 reported an adverse event following immunization (AEFI). We found an overall frequency of 3.4% (377 cases) or 4.8 cases per 100,000 doses administered. Anatomically, the arms (61%) and face/neck region (36.2%) were the most commonly affected sites. The control group had significantly higher rates of reactogenicity-associated symptoms, suggesting that NSSS are reactogenicity-independent; in multivariable analysis, healthcare workers reported sensory symptoms less frequently (aOR 0.54; 95% CI 0.40-0.72;p < 0.001). This is the first study describing the topography and associated factors for developing NSSS among BNT162b2 recipients. The benign nature of these symptoms may help dissipate hesitation towards this vaccine.

Not everything is as it seems: neurosarcoidosis presenting as leptomeningitis.

Involvement of the central nervous system in sarcoidosis is rare; neurosarcoidosis, although unusual, can present as leptomeningitis. The diagnosis is usually difficult because of the vague and broad symptomatology; therefore, a prompt diagnosis should be made, and adequate treatment should be administered to reduce morbidity and mortality.

Utility of [18F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Scan in Inflammatory Myopathies: Case Report and Literature Review.

INTRODUCTION: Inflammatory myopathies are a rare group of diseases characterized by proximal weakness. Incidence ranges from 7.98/million/year and prevalence at 14/100,000. The utility of [18F] fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan is increasing for the complementary diagnosis of myopathies. CASE REPORT: An 84-year-old male was admitted with a history of difficulty rising from a chair and a fall. Laboratory results showed increased creatine kinase levels of more than 50 times the normal reference values. Electromyography (EMG) showed myopathic changes, and FDG-PET/CT scan showed increased FDG uptake in bilateral quadriceps. A biopsy was performed revealing lymphocytic predominant infiltrates and myonecrosis. Prednisone and intravenous immunoglobulin (IVIG) were administered with strength improvement. The patient was discharged for further follow-up. DISCUSSION: FDG-PET/CT in inflammatory diseases has proven useful as muscle fibers have increased FDG uptake. In some cases, FDG-PET/CT is also useful in determining associated neoplastic diseases.

[Tumors of the central nervous system]. / Tumores del sistema nervioso central.

Central nervous system (CNS) tumors constitute a heterogeneous group of neoplasms that share a considerable morbidity and mortality rate. Recent advances in the underlying oncogenic mechanisms of these tumors have led to new classification systems, which, in turn, allow for a better diagnostic approach and therapeutic planning. Most of these neoplasms occur sporadically and several risk factors have been found to be associated with their development, such as exposure to ionizing radiation or electromagnetic fields and the concomitant presence of conditions like diabetes, hypertension and Parkinson's disease. A relatively minor proportion of primary CNS tumors occur in the context of hereditary syndromes. The purpose of this review is to analyze the etiopathogenesis, clinical presentation, diagnosis and therapy of CNS tumors with particular emphasis in the putative risk factors mentioned above.

Los tumores del sistema nervioso central (SNC) constituyen un grupo heterogéneo de neoplasias que tienen en común una morbimortalidad considerable. Los avances recientes en los mecanismos oncogénicos responsables del desarrollo de estos tumores han dado lugar a nuevos sistemas de clasificación, los cuales, a su vez, permiten un mejor abordaje diagnóstico y una mejor planificación terapéutica. La mayoría de estos tumores ocurren en forma esporádica y son varios los factores de riesgo que se han asociado a su desarrollo, tales como la exposición a radiaciones ionizantes o a ondas electromagnéticas, y la presencia de enfermedades como la diabetes, la hipertensión arterial y la enfermedad de Parkinson. Una proporción menor de casos de tumores primarios del SNC es causada debido a síndromes hereditarios. El propósito de esta revisión es resumir de manera integral la etiopatogenia, la presentación clínica, el diagnóstico y el tratamiento de los tumores del SNC y analizar objetivamente el papel que juegan en su desarrollo los factores de riesgo anteriormente mencionados.

Atypical Proliferating Trichilemmal Cyst with Malignant Breast Skin Transformation: A Case Report and Review of the Literature.

Proliferating trichilemmal tumors (PTTs) are benign adnexal skin neoplasms that arise from the outer root sheath of the hair follicle. These tumors are most commonly observed on the scalp and occur, most of the time, in elderly women. Malignant transformation of these neoplasms is a rare event; less than 50 cases have been reported in the English medical literature. We present the case of a 39-year-old Hispanic woman with a tumor located on the skin of one of her breasts that in her third surgical procedure the histologic examination revealed the presence of a malignant proliferating trichilemmal tumor (MPTT). Furthermore, a review of the medical literature and a discussion of the clinical and pathologic features of this rare entity are provided.

[Use of chemotherapy during pregnancy]. / Uso de quimioterapia durante el embarazo.

The presence of malignant tumors during pregnancy complicates the management of both tumor and pregnancy, since any diagnostic or therapeutic intervention could imply risks that may bring on detrimental effects to fetus or mother. The risks involved in exposing a fetus to cytotoxic therapy are associated to gestational age and the time of in utero exposure to that therapy. Cancer treatment has two different objectives: local control by surgery and radiotherapy, and one that seeks to eradicate systemic disease through chemotherapy, immunotherapy, hormone therapy, or targeted therapies.

La presencia de tumores malignos durante la gestación complica tanto el manejo como el propio embarazo, ya que cualquier intervención diagnóstica o terapéutica puede conllevar riesgos que puedan generar efectos nocivos para la madre o para el feto. Los riesgos que tiene un feto sometido a la administración de la terapia citotóxica se correlacionan directamente con la edad gestacional y con el tiempo de la exposición intrauterina a la misma. El tratamiento antineoplásico busca dos objetivos principales; el primero es el control local por medio de cirugía complementada con radioterapia; el segundo busca erradicar la enfermedad sistémica a través de quimioterapia, inmunoterapia, hormonoterapia o terapias blanco.

The possibility of inventing new technologies in the detection of cancer by applying elements of the canine olfactory apparatus.

In order to find better tools in the diagnosis of cancer in an earlier and more precise manner, researchers have explored the use of volatile organic compound (VOCs) as a way to detect this disease. Interestingly, the canine olfactory apparatus was observed to detect cancer in two anecdotal reports. After the description of these events, researchers began to study this phenomenon in a structured way in order to assess the ability of canines in detecting cancer-related VOCs. Due to the fact that some of these studies have shown that the canine olfactory apparatus is highly proficient in the detection of cancer-related VOCs, in this article we assess the possibility of constructing a bioelectronic-nose, based on canine olfactory receptors (ORs), for the purpose of diagnosing cancer in a more sensitive, specific, and cost effective manner than what is available nowadays. Furthermore, in order to prove the feasibility and the need of the proposed apparatus, we searched for the following type of articles: all of the studies that have examined, to our knowledge, the ability of dogs in detecting cancer; articles that assess the dog olfactory receptor (OR) gene repertoire, since a central part of the proposed bioelectronic nose is being able to recognize the odorant that emanates from the cancerous lesion, and for that purpose is necessary to express the canine ORs in heterologous cells; examples of articles that depict different devices that have been built for the purpose of detecting cancer-related VOCs, so as to assess if the construction of the proposed apparatus is needed; and articles that describe examples of already constructed bioelectronic noses, in order to demonstrate the existence of a technical precedent and thus the plausibility of the proposed device.