Traditional first-line treatment failure rates in neuromyelitis optica spectrum disorder patients included in the Argentinean registry (RelevarEM).

BACKGROUND: Immunosuppressive therapies as azathioprine (AZA), mycophenolate mofetil (MMF) and rituximab (RTX) are widely prescribed as first-line treatment to prevent relapses in NMOSD. However, the rate of response to these traditional therapies is unknown in Argentina. We aimed to describe and compare treatment failure rates in NMOSD patients included in the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177). METHODS: A retrospective cohort study was conducted in NMOSD patients included in RelevarEM (a nationwide, longitudinal, observational, non-mandatory registry of MS and NMOSD in Argentina). NMOSD patients were defined based on validate diagnostic criteria. Only NMOSD patients who received AZA or MMF for at least 6 months or RTX for at least 1 month were included. Patients who were receiving AZA, MMF, or RTX and then switched to another 1 of these 3 therapies were included if the above-mentioned criteria for each drug were fulfilled. Data on patient demographics, clinical, neuroradiological findings, and treatments administered were collected. Treatment failure was defined as any new attack/relapse that occurred despite immunosuppressive treatment. RESULTS: We included 139 NMOSD patients who were receiving AZA (n = 105), MMF (n = 5) or RTX (n = 29) with a mean follow-up time of 41.3 ± 11.4 months and median of EDSS at treatment initiation of 3. We observed a reduction in the annualized relapse rate from pre-treatment to post-treatment of 51.1 %, 48.4 %, and 79.1 % respectively with a Hazard Risk relative to RTX (95 % CI) of 1.67 (1.34-3.54, p = 0.01) for AZA and 2.01 (1.86-4.43, p = 0.008) for MMF. AZA, MMF and RTX failure was observed in 45/105 (42.8 %), 2/5 (40 %) and 3/29 (10.3 %) patients, respectively. CONCLUSIONS: Treatment failure rates were higher for AZA and MMF than RTX in Argentinean NMOSD patients in a real-world setting. High-efficacy treatment increases the opportunity to prevent attacks of NMOSD.

Real-World Effectiveness and Safety of Cladribine in Multiple Sclerosis: Longitudinal Data From the Nationwide Registry in Argentina.

OBJECTIVE: The aim was to evaluate patient profiles, effectiveness and safety of cladribine (CLAD) in patients with relapsing-remitting multiple sclerosis in Argentina. METHODS: This was a substudy included in RelevarEM (MS and neuromyelitis optica registry in Argentina, NCT03375177). Patients with MS who received CLAD tablets and were followed up for at least 24 months were included. Clinical evaluations every 3 months collect information about: a) clinical relapses; b) progression of physical disability, evaluated through Expanded Disability Status Scale, and c) new lesions found in the magnetic resonance imaging. Lymphopenia was evaluated during the follow-up and defined as grade 1: absolute lymphocyte count (ALC) 800-999/µL; grade 2: ALC 500-799/µL; grade 3: ALC 200-499/µL and grade 4: ALC <200/µL. RESULTS: A total of 240 patients were included from 19 centers from Argentina. The mean annualized relapse rate during the 12-month pre-CLAD initiation was 1.19 ± 0.56 versus 0.22 ± 0.18 at month 12 and 0.19 ± 0.15 at month 24 ( P < 0.001). A total of 142 (59.2%) fulfilled the criteria of disease activity during the 12 months before treatment initiation, whereas 27 (11.3%) fulfilled it at month 12 and 38 (15.8%) at month 24, P < 0.001. Regarding no evidence of disease activity (NEDA), 202 (84.2%) patients achieved NEDA status at month 12 and 185 (77%) at month 24. The most frequent incidence density of lymphopenia for course 2 observed was also for grade 1, 6.1 (95% confidence interval [CI] = 5.5-7.1). The overall incidence density of lymphopenia grade 4 was 0.1 (95% CI = 0.06-0.19). CONCLUSION: This information will help when choosing the best treatment option for Argentinean patients.

Clinical effectiveness of dimethyl fumarate in multiple sclerosis patients from Argentina.

BACKGROUND: We assessed the effectiveness, safety and patient-reported outcomes (PROs) of dimethyl fumarate (DMF) in real-world clinical practice in patients with multiple sclerosis (PwMS) from Argentina. METHODS: We conducted a multicenter ambispective cohort study in Argentina between September 2020 and March 2023. Changes in annualized relapse rate (ARR), Expanded Disability Status Scale (EDSS) score, magnetic resonance imaging (MRI), no evidence of disease activity (NEDA), PROs (depression, anxiety, fatigue, burden of treatment and quality of life), and safety data were collected at clinical visits performed every 6 months for at least 24 months. RESULTS: We included 161 PwMS (64% female). DMF treatment was associated with a significant reduction in ARR from baseline after 24 months of treatment (from 0.87 to 0.23, p < 0.001). Disability progression was observed in 27.9% vs. 9.3% pre- and post-DMF, and disability improvement was found in 13% of patients from baseline to month 24. MRI activity was significantly reduced compared with baseline. Fatigue, depression, and quality of life scores were significantly improved from baseline to 24 months. Flushing was the most frequent adverse event reported in 19.2%. No significant reduction was observed in the hospitalization rate pre- and post-DMF (19.8% vs. 5.6%, p = 0.32). During follow-up, 135 (83%) patients were relapse-free, 110 (68.3%) were MRI free activity (Gad + lesion) and 108 (67%) reached NEDA. CONCLUSIONS: DMF significantly reduced disease activity in PwMS from Argentina with a good safety profile in real-world settings. A significant impact on the quality of life during follow-up was found.

Treatment strategies and responses for attacks of neuromyelitis optica spectrum disorder: A real-world retrospective cohort study.

We aimed to assess the treatment strategies utilized in patients with neuromyelitis optica spectrum disorder (NMOSD) experiencing relapses, including their frequency, types, and response after 6 months based on the Expanded Disability Status Scale (EDSS) score. METHODS: We conducted a retrospective study involving NMOSD patients from the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177). Treatment response at 6 months was categorized as "good" if the EDSS score decreased by ≥1 point after a nadir EDSS score ≤ 3, or by ≥2 points after a nadir EDSS score > 3, "poor" if the EDSS score decrease was slighter, and as "absent" if the EDSS score remained unchanged or worsened. RESULTS: We included 120 NMOSD patients (seropositive N = 75), who experienced 250 NMOSD-related relapses and received 248 treatments. At 6 months, complete recovery was achieved in 70/98 (71.4%) and 15/19 (79%) patients, respectively. Predictors of a "good" response in our regression model were a younger age at disease onset (OR:3.54, CI95% 2.45-5.01, p < 0.0001) and a short delay from onset of relapse to treatment initiation (OR:1.56, CI95% 1.22-2.13, p = 0.004). CONCLUSIONS: Approximately two-thirds of patients experienced complete recovery, and younger age and a short delay to start treatment were independent predictors of a "good" response.

Occurrence of area postrema syndrome during follow-up: phenotype and influence over NMOSD activity in LATAM in real-world settings.

INTRODUCTION: We aimed to assess the frequency, duration, and severity of area postrema syndrome (APS) during follow-up in neuromyelitis optica spectrum disorder (NMOSD) patients, as well as its association with inflammatory activity and prognostic factors of APS severity in a real-world setting. METHODS: We conducted a retrospective study on a cohort of Latin American (LATAM) NMOSD patients who had experienced APS during their follow-up. Patients from Mexico, Peru, Brazil, Colombia, Panama, Chile and Argentina patients who met 2015 NMOSD criteria were included. We evaluated data on symptom type (nausea, vomiting and/or hiccups), frequency, duration, severity (measured by APS severity scale), association with other NMOSD core relapses, and acute treatments (symptomatic and immunotherapy or plasmapheresis). Logistic regression was conducted to evaluate factors associated with APS severity (vs. mild-moderate). RESULTS: Out of 631 NMOSD patients, 116 (18.3%) developed APS during their follow-up. The most common APS phenotype was severe. Inflammatory activity (i.e., relapses) significantly decreased after the onset of APS. Half of the patients experienced isolated APS with a median duration of 10 days, and the most frequently used acute treatment was IV steroids. All three symptoms were present in 44.6% of the patients. APS symptoms resolved following immunotherapy. Logistic regression did not identify independent factors associated with the severity of APS. CONCLUSIONS: Our findings indicate that 18.3% of NMOSD patients developed APS during the follow-up period, with most patients fulfilling criteria for severe APS. The inflammatory activity decreased after the onset of APS compared to the previous year.

Incidence of SARS-CoV-2 infection in patients with multiple sclerosis who received SARS-CoV-2 vaccines and are under treatment with high-efficacy therapies in Argentina.

We aimed to evaluate the incidence of SARS-CoV-2 breakthrough infection of SARS-CoV-2 vaccines in people with MS (PwMS) on high-efficacy disease-modifying therapies (HET) included in the national MS registry in Argentina (RelevarEM). METHODS: Non-interventional, retrospective cohort study that collected information directly from RelevarEM. Adult PwMS who had been treated for at least 6 months with a HET (ocrelizumab, natalizumab, alemtuzumab, cladribine) who had received at least two doses of SARS-CoV-2 vaccines available in Argentina were included. Full course of vaccination was considered after the second dose of the corresponding vaccines. Cumulative incidence of SARS-CoV-2 infection was reported for the whole cohort by Kaplan-Meier survival curves (which is expressed in percentage) as well as incidence density (which is expressed per 10.000 patients/day with 95% CI). RESULTS: Two hundred twenty-eight PwMS were included. Most frequent first and second dose received was AstraZeneca vaccine, followed by Sputnik vaccine. Most frequent HETs used in included patients were cladribine in 79 (34.8%). We found an incidence density of breakthrough COVID-19 infection of 3.5 × 10.000 patients/day (95% CI 2.3-6.7) after vaccination in Argentina. We described the incidence rate after vaccination for every HET used, it being significantly higher for ocrelizumab compared with other HETs (p = 0.005). Only five patients presented a relapse during the follow-up period with no differences regarding the pre-vaccination period. CONCLUSIONS: We found an incidence density of breakthrough COVID-19 infection of 3.5 × 10.000 patients/day (95% CI 2.3-6.7) after vaccination in Argentina.

[Ultrasound guided biopsy of lung tumors: evaluation of efficacy and complications]. / Biopsia de tumores pulmonares con guía ecográfica: evaluación de eficacia y complicaciones

Introduction: The diagnosis of lung cancer, as well as that of lung nodules, is increasing. Percutaneous biopsy has become a transcendental tool for its diagnosis. Traditionally, computed tomography is used for these procedures because of its ability to clearly demonstrate bone and aerated lung. However, in selected cases it can be performed with ultrasound. Methods: Retrospective study conducted between January 2020 and December 2021, during the SARS-CoV-2 pandemic. All patients had pleural-based lung lesions or pleural lesions, some with a known history of cancer. Results: Thirty-six procedures were performed, in 32 (88.9%) the sample obtained presented diagnostic yield and the most used additional test was Immunohistochemistry in 23 (63.9%). Complications were reported in 5 patients (13.9%): 2 with mild pneumothorax, 2 with hemothorax (1 mild and 1 moderate) and 1 patient reported pain. Conclusion: Ultrasound is a valid method to be used as a guide for biopsies of pleural and peripheral pulmonary lesions. The complications and diagnostic rate has been shown to be in line with the experience of other authors and international guidelines.

Introducción: El diagnóstico de cáncer pulmonar al igual que el de los nódulos pulmonares se encuentra en aumento. La biopsia percutánea se ha convertido en una herramienta trascendental para su diagnóstico. Tradicionalmente la tomografía computada es empleada para estos procedimientos por su capacidad para demostrar con claridad los huesos y el pulmón aireado. Sin embargo, en casos seleccionados puede efectuarse con ecografía. Métodos: Estudio retrospectivo realizado entre enero de 2020 y diciembre de 2021, durante la pandemia por SARS-CoV-2. Todos los pacientes tenían lesiones pulmonares de base pleural o lesiones pleurales, algunos con antecedentes conocidos de cáncer. Resultados: Se realizaron 36 procedimientos, en 32 (88,9%) la muestra obtenida presentó rédito diagnóstico y la prueba adicional más utilizada fue la Inmunohistoquímica en 23 (63,9%). Se reportaron complicaciones en 5 pacientes (13,9%): 2 con neumotórax leve, 2 con hemotórax (1 leve y 1 moderado) y 1 paciente refirió dolor. Conclusión: La ecografía es un método válido para ser usado como guía de biopsias de lesiones pleurales y pulmonares periféricas. La tasa de complicaciones y reedito diagnóstico ha demostrado estar en línea con la experiencia de otros autores y guías internacionales.

Mortality of neuromyelitis optica spectrum disorder patients in an Argentinean population: A study from the RelevarEM registry.

We aimed to evaluate mortality and causes of death among Argentinean neuromyelitis optica spectrum disorder (NMOSD) patients and identify predictors of death. Retrospective study included 158 NMOSD patients and 11 (7%) patients died after 11 years of follow-up for a total exposure time of 53,345 days with an overall incidence density of 2.06 × 10.000 patients/day (95% CI 1.75-2.68). Extensive cervical myelitis with respiratory failure (45%) was the most frequent cause of death. Older age (HR = 2.05, p = 0.002) and higher disability score (HR = 2.30, p < 0.001) at disease onset were independent predictors of death. We found an 11-year mortality rate of 7% in Argentinean NMOSD patients.

Frequency of new asymptomatic MRI lesions during attacks and follow-up of patients with NMOSD in a real-world setting.

BACKGROUND: We aimed to assess the frequency of new asymptomatic lesions on brain and spinal imaging (magnetic resonance imaging (MRI)) and their association with subsequent relapses in a large cohort of neuromyelitis optica spectrum disorder (NMOSD) patients in Argentina. METHODS: We retrospectively reviewed 675 MRI (225 performed during an attack and 450 during the relapse-free period (performed at least 3 months from the last attack)) of NMOSD patients who had at least 2 years of clinical and MRI follow-up since disease onset. Kaplan-Meier (KM) curves were used for depicting time from remission MRI to subsequent relapse. RESULTS: We included 135 NMOSD patients (64.4% were aquaporin-4-immunoglobulin G (AQP4-IgG)-positive). We found that 26 (19.26%) and 66 (48.88%) of patients experienced at least one new asymptomatic MRI lesion during both the relapse-free period and attacks, respectively. The most frequent asymptomatic MRI lesions were optic nerves followed by short-segment myelitis during the relapse-free period and attacks. KM curves did not show differences in the time taken to develop a new relapse. CONCLUSION: Our findings showed that new asymptomatic lesions are relatively frequent. However, the presence of new asymptomatic MRI lesions during the relapse-free period and at relapses was not associated with a shorter time to developing subsequent relapses.

Development and validation of nonattendance predictive models for scheduled adult outpatient appointments in different medical specialties.

INTRODUCTION: Nonattendance is a critical problem that affects health care worldwide. Our aim was to build and validate predictive models of nonattendance in all outpatients appointments, general practitioners, and clinical and surgical specialties. METHODS: A cohort study of adult patients, who had scheduled outpatient appointments for General Practitioners, Clinical and Surgical specialties, was conducted between January 2015 and December 2016, at the Italian Hospital of Buenos Aires. We evaluated potential predictors grouped in baseline patient characteristics, characteristics of the appointment scheduling process, patient history, characteristics of the appointment, and comorbidities. Patients were divided between those who attended their appointments, and those who did not. We generated predictive models for nonattendance for all appointments and the three subgroups. RESULTS: Of 2,526,549 appointments included, 703,449 were missed (27.8%). The predictive model for all appointments contains 30 variables, with an area under the ROC (AUROC) curve of 0.71, calibration-in-the-large (CITL) of 0.046, and calibration slope of 1.03 in the validation cohort. For General Practitioners the model has 28 variables (AUROC of 0.72, CITL of 0.053, and calibration slope of 1.01). For clinical subspecialties, the model has 23 variables (AUROC of 0.71, CITL of 0.039, and calibration slope of 1), and for surgical specialties, the model has 22 variables (AUROC of 0.70, CITL of 0.023, and calibration slope of 1.01). CONCLUSION: We build robust predictive models of nonattendance with adequate precision and calibration for each of the subgroups.

Disability outcomes in NMOSD and MOGAD patients: data from a nationwide registry in Argentina.

The objective was to evaluate time to reach an EDSS of 4, 6, and 7 in NMOSD and MOGAD patients included in the Argentinean MS and NMOSD registry (RelevarEM, NCT 03,375,177). METHODS: NMOSD patients diagnosed according to 2015 criteria and with MOGAD were identified. Patients with at least 3 years of follow-up and periodic clinical evaluations with EDSS outcomes were included. AQP4-antibody and MOG-antibody status was recorded, and patients were stratified as seropositive and seronegative for AQP4-antibody. EDSS of 4, 6, and 7 were defined as dependent variables. Log rank test was used to identify differences between groups. RESULTS: Registry data was provided for a total of 137 patients. Of these, seventy-five presented AQP4-ab-positive NMOSD, 45 AQP4-ab-negative NMOSD, and 11 MOGAD. AQP4-ab status was determined by cell-based assay (CBA) in 72% of NMOSD patients. MOG-ab status was tested by CBA in all cases. Mean time to EDSS of 4 was 53.6 ± 24.5 vs. 63.1 ± 32.2 vs. 44.7 ± 32 months in seropositive, seronegative NMOSD, and MOGAD, respectively (p = 0.76). Mean time to EDSS of 6 was 79.2 ± 44.3 vs. 75.7 ± 48.6 vs. 54.7 ± 50 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.23), while mean time to EDSS of 7 was 86.8 ± 54 vs. 80.4 ± 51 vs. 58.5 ± 47 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.39). CONCLUSION: No differences were observed between NMOSD (seropositive and seronegative) and MOGAD in survival curves.

Accumulative risk of clinical event in high-risk radiologically isolated syndrome in Argentina: data from the nationwide registry RelevarEM.

INTRODUCTION: We aimed to analyze the accumulative risk of MRI and OB factors for evolution from RIS to MS in subjects included in the Argentinean MS registry (NCT03375177). METHODS: RIS subjects were identified according to RIS diagnosis criteria. Subjects were longitudinally followed with clinical and MRI at intervals of 6 months. Time from RIS identification to the first clinical event was estimated using Kaplan-Meier. Multivariable Cox regression models were created to assess the independent predictive value of demographic characteristics, as well as clinical, OB and MRI data on time to the first clinical event. The single and increased risk factor of evolution of RIS was quantified. RESULTS: A total of 88 RIS subjects, mean follow-up time 42 ± 4 months were included. 39 (44.3%) and 23 (26.1%) had a new MRI lesion or a clinical event, respectively, during the follow-up. OB (HR 5.9, 95% CI 1.29-10.1, p = 0.004), infratentorial lesions (HR 3.7, 95% CI 1.09-7.5) and spinal cord lesions (HR 5.3, 95% CI 1.4-8.2, p = 0.01) at RIS identification were independent predictors associated with a subsequent clinical event. The accumulative risk showed that when two of the three factors (OB, infratentorial or spinal cord lesions) were present the HR was 10.4, 95% CI 4.4-22, p < 0.001, and when three factors were present, it was HR 15.6, 95% CI 5.7-28, p < 0.001 for a relapse. CONCLUSION: The presence of three factors significantly increased the risk of clinical event; high-risk subjects should probably be managed by a different approach than those used for individuals without high-risk factors.

Seasonal variation in attacks of neuromyelitis optica spectrum disorders and multiple sclerosis: Evaluation of 794 attacks from a nationwide registry in Argentina.

BACKGROUND: Identification of triggers that potentially instigate attacks in neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) has remained challenging. We aimed to analyze the seasonality of NMOSD and MS attacks in an Argentinean cohort seeking differences between the two disorders. METHODS: A retrospective study was conducted in a cohort of NMOSD and MS patients followed in specialized centers from Argentina and enrolled in RelevarEM, a nationwide, longitudinal, observational, non-mandatory registry of MS/NMOSD patients. Patients with complete relapse data (date, month and year) at onset and during follow-up were included. Attack counts were analyzed by month using a Poisson regression model with the median monthly attack count used as reference. RESULTS: A total of 551 patients (431 MS and 120 NMOSD), experiencing 236 NMOSD-related attacks and 558 MS-related attacks were enrolled. The mean age at disease onset in NMOSD was 39.5 ± 5.8 vs. 31.2 ± 9.6 years in MS (p < 0.01). Mean follow-up time was 6.1 ± 3.0 vs. 7.4 ± 2.4 years (p < 0.01), respectively. Most of the included patients were female in both groups (79% vs. 60%, p < 0.01). We found a peak of number of attacks in June (NMOSD: 28 attacks (11.8%) vs MS: 33 attacks (5.9%), incidence rate ratio 1.82, 95%CI 1.15-2.12, p = 0.03), but no differences were found across the months in both disorders when evaluated separately. Strikingly, we observed a significant difference in the incidence rate ratio of attacks during the winter season when comparing NMOSD vs. MS (NMOSD: 75 attacks (31.7%) vs MS: 96 attacks (17.2%), incidence rate ratio 1.82, 95%CI 1.21-2.01, p = 0.02) after applying Poisson regression model. Similar results were observed when comparing the seropositive NMOSD (n = 75) subgroup vs. MS. CONCLUSIONS: Lack of seasonal variation in MS and NMOSD attacks was observed when evaluated separately. Future epidemiological studies about the effect of different environmental factors on MS and NMOSD attacks should be evaluated prospectively in Latin America population.

Assessing attacks and treatment response rates among adult patients with NMOSD and MOGAD: Data from a nationwide registry in Argentina.

We aimed to examine treatment interventions implemented in patients experiencing neuromyelitis optica spectrum disorders (NMOSD) attacks (frequency, types, and response). METHODS: Retrospective study. Data on patient demographic, clinical and radiological findings, and administered treatments were collected. Remission status (complete [CR], partial [PR], no remission [NR]), based on changes in the EDSS score was evaluated before treatment, during attack, and at 6 months. CR was analyzed with a generalized estimating equations (GEEs) model. RESULTS: A total of 131 patients (120 NMOSD and 11 myelin oligodendrocyte glycoprotein-antibody-associated diseases [MOGAD]), experiencing 262 NMOSD-related attacks and receiving 270 treatments were included. High-dose steroids (81.4%) was the most frequent treatment followed by plasmapheresis (15.5%). CR from attacks was observed in 47% (105/223) of all treated patients. During the first attack, we observed CR:71.2%, PR:16.3% and NR:12.5% after the first course of treatment. For second, third, fourth, and fifth attacks, CR was observed in 31.1%, 10.7%, 27.3%, and 33.3%, respectively. Remission rates were higher for optic neuritis vs. myelitis (p < 0.001). Predictor of CR in multivariate GEE analysis was age in both NMOSD (OR = 2.27, p = 0.002) and MOGAD (OR = 1.53, p = 0.03). CONCLUSIONS: This study suggests individualization of treatment according to age and attack manifestation. The outcome of attacks was generally poor.

Research priorities in multiple sclerosis in Latin America: A multi-stakeholder call to action to improve patients care: Research priorities in MS in LATAM.

As human and economic resources are limited, especially in Latin America (LATAM), it is important to identify research priorities to improve multiple sclerosis (MS) patients care in the region. The objective was to generate a multidisciplinary consensus on research priorities in MS for patients care in LATAM by involving healthcare professionals and MS patient associations. METHODS: consensus was reached through a four-step modified Delphi method designed to identify and rate research priorities in MS in LATAM. The process consisted of two qualitative assessments, a general ranking phase and a consensus meeting followed by a more detailed ranking phase RESULTS: a total of 62 participants (35 neurologists, 4 nurses, 12 kinesiologists, 7 neuropsychologists and 4 patient association members) developed the process. At the final ranking stage following the consensus meeting, each participant provided their final rankings, and the top priority research questions were outlined. 11 research priorities were identified focusing on healthcare access, costs of the disease, physical and cognitive evaluation and rehabilitation, quality of life, symptoms management, prognostic factors, the need of MS care units and patient's management in emergencies like COVID-19. CONCLUSION: this work establishes MS research priorities in LATAM from multiple perspectives. To pursue the actions suggested could launch the drive to obtain information that will help us to better understand the disease in our region and, especially, to better care for affected patients.

What percentage of AQP4-ab-negative NMOSD patients are MOG-ab positive? A study from the Argentinean multiple sclerosis registry (RelevarEM).

BACKGROUND: Myelin oligodendrocyte glycoprotein antibodies (MOG-ab) have been described in aquaporin-4-antibodies(AQP4-ab)-negative neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to evaluate the percentage of AQP4-ab-negative NMOSD patients who are positive for MOG-ab in a cohort of Argentinean patients included in RelevarEM (Clinical Trials registry number NCT03375177). METHODS: RelevarEM is a longitudinal, strictly observational multiple sclerosis (MS) and NMOSD registry in Argentina. Of 3031 consecutive patients (until March 2020), 165 patients with phenotype of suspected NMOSD, whose relevant data for the purpose of this study were available, were included. Data on demographic, clinical, paraclinical and treatment in AQP4-ab (positive, negative and unknown) and MOG-ab (positive and negative) patients were evaluated. RESULTS: A total of 165 patients (79 AQP4-Ab positive, 67 AQP4-Ab negative and 19 unknown) were included. Of these, 155 patients fulfilled the 2015 NMOSD diagnostic criteria. Of 67 AQP4-Ab-negative patients, 36 (53.7%) were tested for MOG-Ab and 10 of them (27.7%) tested positive. Serum AQP4-ab levels were tested by means of cell-based assay (CBA) in 48 (35.2%), based on tissue-based indirect immunofluorescence assays in 58 (42.6%) and enzyme-linked immunosorbent assay in 4 (2.9%). All MOG-ab were tested by CBA. Optic neuritis (90%) was the most frequent symptom at presentation and optic nerve lesions the most frequent finding (80%) in neuroimaging of MOG-ab-associated disease. Of these, six (60%) patients were under immunosuppressant treatments at latest follow-up. CONCLUSION: We observed that 27.7% (10/36) of the AQP4-ab-negative patients tested for MOG-ab were positive for this antibody, in line with results from other world regions.

Prevalence and risk factors of long-term proton pump inhibitors-associated hypomagnesemia: a cross-sectional study in hospitalized patients.

BACKGROUND: Proton pump inhibitors (PPI)-related hypomagnesemia is a potentially life-threatening adverse event first described in 2006. PPIs are widely used in the general population. Information regarding prevalence and risk factors is scarce. We conducted a cross-sectional study in inpatients to evaluate prevalence and associated factors with hypomagnesemia in chronic PPIs users. This is a cross-sectional study of hospitalized adult patients with chronic use of PPIs from January 01, 2012, to December 31, 2018. Chronic use was defined as taking PPIs at least 6 months before hospital admittance. Data were collected from informatized medical records from a University Hospital (Hospital Italiano de Buenos Aires). Hypomagnesemia was defined as a value equal to or less than 1.7 mg/dl. The first hospitalization measurement was retrieved. Thirty-six percent of patients (95% CI 30-43) with chronic PPI use presented hypomagnesemia at admission. Patients with hypomagnesemia presented a higher prevalence of chronic kidney disease (18.6% vs 8%, p < 0.05), more use of oral magnesium supplementation (20.9% vs 8%, p < 0.05), use of corticosteroids (32.6% vs 19.3%, p = 0.06) and calcineurin inhibitors (17.4% vs 6.7%, p < 0.05). Regarding laboratory findings, they presented lower hematocrit (28.7% vs 32.8%, p < 0.05), phosphatemia (3 mg/dl vs 3.4 mg/dl, p < 0.05), natremia (135 mg/dl vs 136 mg/dl, p < 0.05) and albumin levels (2.8 g/dl vs 3.2 g/dl p < 0.05) when compared to those who presented normomagnesemia. Hypocalcemia was more frequent among patients with hypomagnesemia (57% vs 38.7%, p < 0.05). In the multivariate analysis, hyponatremia, decreasing levels of hematocrit (odds ratio, OR 0.93-CI 95% 0.88-0.98) and malignant bone compromise (OR 2.83-CI 95% 1.04-7.7) were associated with hypomagnesemia. Adult patients with long-term use of PPIs have a high prevalence of hypomagnesemia. Increasing age, female sex, concomitant use of drugs that impair tubular function and chronic kidney disease may enhance this phenomenon. Anemia, hyponatremia and malignant bone compromise were associated factors with PPIs-related hypomagnesemia.

Aspectos clínicos y demográficos de los pacientes con esclerosis múltiple secundaria progresiva en Argentina / Clinical and demographic aspects of secondary progressive multiple sclerosis in Argentina

Resumen El objetivo del estudio fue evaluar los aspectos clínicos y demográficos de los pacientes con esclerosis múltiple (EM) secundaria progresiva (EMSP) en los pacientes incluidos en el Registro Argentino de EM (RelevarEM, número de registro de Clinical Trials 03375177). RelevarEM es un registro longitudinal, estrictamente observacional, de pacientes con EM y trastornos del espectro de neuromielitis óptica. Los aspectos clínicos y demográficos fueron descriptos en pacientes con EMSP respecto a aquellos con EM recaída en remisión (EMRR). Se incluyeron 1723 pacientes con EM (1605, 93.2% EMRR y 118, 6.8%, EMSP). En el grupo con EMSP la mediana de edad fue de 53 (intervalo inter-cuartil [IIQ] 47-62) años, 67% eran mujeres, mediana de tiempo de evolución de enfermedad 19.5 (IIQ 14-26) años, EDSS (expanded disability status scale), 6.5 y 48.3% estaban en tratamiento para su EM. Solo el 23.7% con EMSP estaban trabajando activamente y el 86% tenía certificado de discapacidad. Un 35.6% con EMSP presentaron nuevas lesiones en resonancia magnética y 5% tuvo recaídas clínicas en los 12 meses previos al análisis, mostrando una actividad de la enfermedad significativamente menor respecto a la forma EMRR (p < 0.01).

Abstract The objective of the study was to describe the clinical and demographic aspects of patients with secondary progressive multiple sclerosis (SPMS) included in the Argentine MS Registry (RelevarEM, Clinical Trials registry number 03375177). RelevarEM is a longitudinal, strictly observational registry of patients with MS and neuromyelitis optica spectrum disorders. Clinical and demographic aspects were described in patients with SPMS and compared with relapsing remitting MS patients (RRMS). A total of 1723 patients with MS were included (1605, 93.2% RRMS and 118, 6.8%, SPMS). In SPMS, the median age was 53 (inter quartile range [IQR] 47-62) years, 67% were women, median disease duration of 19.5 (IQR 14-26) years, median EDSS (expanded disability status scale) 6.5 and 48.3% were under treatment for their MS. Only 23.7% of patients with SPMS were actively working and 86% had a disability certificate; 35.6% of patients with SPMS presented new lesions in MRI and 5% had clinical relapses during the past 12 months of the registry entry showing a significantly lower disease activity compared with RRMS (p < 0.01).

[Clinical and demographic aspects of secondary progressive multiple sclerosis in Argentina]. / Aspectos clínicos y demográficos de los pacientes con esclerosis múltiple secundaria progresiva en Argentina.

The objective of the study was to describe the clinical and demographic aspects of patients with secondary progressive multiple sclerosis (SPMS) included in the Argentine MS Registry (RelevarEM, Clinical Trials registry number 03375177). RelevarEM is a longitudinal, strictly observational registry of patients with MS and neuromyelitis optica spectrum disorders. Clinical and demographic aspects were described in patients with SPMS and compared with relapsing remitting MS patients (RRMS). A total of 1723 patients with MS were included (1605, 93.2% RRMS and 118, 6.8%, SPMS). In SPMS, the median age was 53 (inter quartile range [IQR] 47-62) years, 67% were women, median disease duration of 19.5 (IQR 14-26) years, median EDSS (expanded disability status scale) 6.5 and 48.3% were under treatment for their MS. Only 23.7% of patients with SPMS were actively working and 86% had a disability certificate; 35.6% of patients with SPMS presented new lesions in MRI and 5% had clinical relapses during the past 12 months of the registry entry showing a significantly lower disease activity compared with RRMS (p < 0.01).

El objetivo del estudio fue evaluar los aspectos clínicos y demográficos de los pacientes con esclerosis múltiple (EM) secundaria progresiva (EMSP) en los pacientes incluidos en el Registro Argentino de EM (RelevarEM, número de registro de Clinical Trials 03375177). RelevarEM es un registro longitudinal, estrictamente observacional, de pacientes con EM y trastornos del espectro de neuromielitis óptica. Los aspectos clínicos y demográficos fueron descriptos en pacientes con EMSP respecto a aquellos con EM recaída en remisión (EMRR). Se incluyeron 1723 pacientes con EM (1605, 93.2% EMRR y 118, 6.8%, EMSP). En el grupo con EMSP la mediana de edad fue de 53 (intervalo inter-cuartil [IIQ] 47-62) años, 67% eran mujeres, mediana de tiempo de evolución de enfermedad 19.5 (IIQ 14-26) años, EDSS (expanded disability status scale), 6.5 y 48.3% estaban en tratamiento para su EM. Solo el 23.7% con EMSP estaban trabajando activamente y el 86% tenía certificado de discapacidad. Un 35.6% con EMSP presentaron nuevas lesiones en resonancia magnética y 5% tuvo recaídas clínicas en los 12 meses previos al análisis, mostrando una actividad de la enfermedad significativamente menor respecto a la forma EMRR (p < 0.01).

Síndrome de absceso hepático invasor por Klebsiella pneumoniae, serie de casos / Invasive liver abscess syndrome caused by Klebsiella pneumoniae, case series

Resumen Introducción: Los abscesos hepáticos primarios producidos por Klebsiella pneumoniae y las implicancias sistémicas relacionadas constituyen el síndrome de absceso hepático invasor por Klebsiella pneumoniae. Objetivo: Describir las características clínicas, epidemiológicas y la evolución de esta entidad en nuestro centro. Pacientes y Métodos: Cohorte retrospectiva de pacientes adultos internados en el Hospital Italiano de Buenos aires entre el 1 de enero de 2001 y el 1 de mayo de 2020. Se incluyeron pacientes con diagnóstico de absceso en cualquier órgano con aislamiento en cultivo de absceso o hemocultivo positivo para Klebsiella pneumoniae para ser analizadas las características epidemiológicas, clínicas y la evolución de aquellos con localización primaria hepática. Resultados: 10 pacientes fueron incluidos. Dos (20%) pacientes fueron orientales. La mediana de edad fue 69 años (IIC 64-79), nueve (90%) fueron hombres. La co-morbilidad más frecuente fue diabetes mellitus tipo 2 (40%). Cuatro (40%) pacientes tuvieron diseminación a otros órganos. La mediana de internación fue 21,5 días (IIC 15-43), 60% (n: 6) requirió internación en unidad de cuidados intensivos y 30% (n: 3) de los pacientes falleció. Conclusión: El síndrome de absceso hepático invasor por Klebsiella pneumoniae es una enfermedad infrecuente, potencialmente mortal. Este estudio intenta reportar las características de los pacientes con esta patología en nuestra población.

Abstract Background: Primary liver abscesses caused by Klebsiella pneumoniae and their related systemic complications produce the invasive liver abscess syndrome due to Klebsiella pneumoniae. Aim: To describe the clinical, epidemiological and evolution characteristics in our center. Methods: A retrospective cohort of hospitalized adults in Hospital Italiano de Buenos Aires between January 1st, 2001 and May 1st, 2020. We included patients with diagnosis of abscess in any organ with rescue in culture or positive blood culture for Klebsiella pneumoniae. Epidemiological, clinical characteristics and prognosis of those with hepatic primary localization were analyzed. Results: 10 patients were included. Two (20%) patients were Oriental. Median age was 69 years (interquartile range 64-79), nine (90%) were men. The most frequent comorbidity was type 2 diabetes (40%). Four (40%) patients had spread to other organs. The median hospitalization was 21.5 days (IIC 15-43), 60% (n: 6) were hospitalized in the intensive care unit and 30% (n: 3) died. Conclusions: The invasive liver abscess syndrome due to Klebsiella pneumoniae is a rare life-threatening disease. Our study reports the characteristics of patients with this syndrome in our population.