Cooperative Response to Endocardial Notch Reveals Interaction With Hippo Pathway.

BACKGROUND: The endocardium is a crucial signaling center for cardiac valve development and maturation. Genetic analysis has identified several human endocardial genes whose inactivation leads to bicuspid aortic valve formation and calcific aortic valve disease, but knowledge is very limited about the role played in valve development and disease by noncoding endocardial regulatory regions and upstream factors. METHODS: We manipulated Notch signaling in mouse embryonic endocardial cells by short-term and long-term coculture with OP9 stromal cells expressing Notch ligands and inhibition of Notch activity. We examined the transcriptional profile and chromatin accessibility landscape for each condition, integrated transcriptomic, transcription factor occupancy, chromatin accessibility, and proteomic datasets. We generated in vitro and in vivo models with CRISPR-Cas9-edited deletions of various noncoding regulatory elements and validated their regulatory potential. RESULTS: We identified primary and secondary transcriptional responses to Notch ligands in the mouse embryonic endocardium, and a NOTCH-dependent transcriptional signature in valve development and disease. By defining the changes in the chromatin accessibility landscape and integrating with the landscape in developing mouse endocardium and adult human valves, we identify potential noncoding regulatory elements, validated selected candidates, propose interacting cofactors, and define the timeframe of their regulatory activity. Additionally, we found cooperative transcriptional repression with Hippo pathway by inhibiting nuclear Yap (Yes-associated protein) activity in the endocardium during cardiac valve development. CONCLUSIONS: Sequential Notch-dependent transcriptional regulation in the embryonic endocardium involves multiple factors. Notch activates certain noncoding elements through these factors and simultaneously suppresses elements that could hinder cardiac valve development and homeostasis. Biorxviv: https://www.biorxiv.org/content/10.1101/2023.03.23.533882v1.full.

Adhesion G protein-coupled receptor Gpr126/Adgrg6 is essential for placental development.

Mutations in the G protein­coupled receptor GPR126/ADGRG6 cause human diseases, including defective peripheral nervous system (PNS) myelination. To study GPR126 function, we generated new genetic mice and zebrafish models. Murine Gpr126 is expressed in developing heart endocardium, and global Gpr126 inactivation is embryonically lethal, with mutants having thin-walled ventricles but unaffected heart patterning or maturation. Endocardial-specific Gpr126 deletion does not affect heart development or function, and transgenic endocardial GPR126 expression fails to rescue lethality in Gpr126-null mice. Zebrafish gpr126 mutants display unaffected heart development. Gpr126 is also expressed in placental trophoblast giant cells. Gpr126-null mice with a heterozygous placenta survive but exhibit GPR126-defective PNS phenotype. In contrast, Gpr126-null embryos with homozygous mutant placenta die but are rescued by placental GPR126 expression. Gpr126-deficient placentas display down-regulation of preeclampsia markers Mmp9, Cts7, and Cts8. We propose that the placenta-heart axis accounts for heart abnormalities secondary to placental defects in Gpr126 mutants.

Bariatric surgery in Mexico: training, practice and surgical trends.

Bariatric surgery is extremely safe and effective, but several factors need to be addressed to obtain such results. Patient selection, type of training, accreditation, type of practice, and surgical trends and technique are involved in this process. Local and global standardization are ill-advised, especially in countries with high obesity prevalence, and where the bariatric practice is fast growing.An online survey with 22 questions was sent to bariatric surgeons in Mexico. Only participants with the active practice were included, and the aim was to obtain for the first time insight in bariatric surgery training, characteristics of current practice and surgical trends.Complete responses from 114 surgeons were obtained. Most were male, under 50 years-old, ≤ 10 years of experience, and practice in low-volume hospitals. Less than half had a 12-month formal training. Gastric bypass and sleeve gastrectomy were the most common procedures. Practice trends like leak tests, use of drains, preoperative weight loss, routine endoscopy, and pharmacological tromboprofilaxis are common. In surgical technique, the gastric bypass and sleeve gastrectomy confection was more homogenic when compared to the one-anastomosis gastric bypass.Complete responses from 114 surgeons were obtained. Most were male, under 50 years-old, ≤ 10 years of experience, and practice in low-volume hospitals. Less than half had a 12-month formal training. Gastric bypass and sleeve gastrectomy were the most common procedures. Practice trends like leak tests, use of drains, preoperative weight loss, routine endoscopy, and pharmacological tromboprofilaxis are common. In surgical technique, the gastric bypass and sleeve gastrectomy confection was more homogenic when compared to the one-anastomosis gastric bypass. An important number of bariatric surgeons in Mexico are young, male, and with < 10 years of practice. The most common techniques performed are gastric bypass and sleeve gastrectomy. Several practices and technique trends are similar to global consensus. Fellowship programs and Board Certification in bariatric surgery are major advances in our country, thus standardization and high-quality practice can be achieved.

SARS-CoV-2 Infection and COVID-19 in 5 Patients in Ecuador After Prior Treatment with Hydroxychloroquine for Systemic Lupus Erythematosus.

BACKGROUND This case series describes 5 patients with SARS-CoV-2 infection and COVID-19 in Ecuador who had been treated with hydroxychloroquine for systemic lupus erythematosus (SLE) prior to their COVID-19 illness. CASE REPORT Case #1 reports a 29-year-old woman who had been treated with 200 mg of hydroxychloroquine per day for 1 year and presented with flu-like symptoms, chest pain, fever, odynophagia, asthenia, dry cough, and chills. Case #2 was a 34-year-old woman whose treatment for SLE included 200 mg of hydroxychloroquine per day since 2017. She arrived at the clinic with a dry cough, asthenia, and myalgias. Case #3 was a 24-year-old woman who had been using 200 mg of hydroxychloroquine per day since 2010. She presented with asthenia, myalgias, headaches, hypogeusia, and anosmia. Case #4 was a 39-year-old woman taking 200 mg of hydroxychloroquine every day for SLE who presented with dyspnea, chest pain, odynophagia, hypogeusia, anosmia, diarrhea, and fever. Case #5 was a 46-year-old woman who had been taking 200 mg of hydroxychloroquine since 2019. She came to our hospital complaining of chest pain, fever, and dyspnea. In all 5 patients, SARS-CoV-2 infection was confirmed with a nasopharyngeal SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) test using the Cepheid/GeneXpert system. CONCLUSIONS All 5 of our patients with SLE who were taking hydroxychloroquine presented with SARS-CoV-2 infection and symptoms of COVID-19. This case series provides support for a lack of prevention of COVID-19 by hydroxychloroquine.

NOTCH Activation Promotes Valve Formation by Regulating the Endocardial Secretome.

The endocardium is a specialized endothelium that lines the inner surface of the heart. Functional studies in mice and zebrafish have established that the endocardium is a source of instructive signals for the development of cardiac structures, including the heart valves and chambers. Here, we characterized the NOTCH-dependent endocardial secretome by manipulating NOTCH activity in mouse embryonic endocardial cells (MEEC) followed by mass spectrometry-based proteomics. We profiled different sets of soluble factors whose secretion not only responds to NOTCH activation but also shows differential ligand specificity, suggesting that ligand-specific inputs may regulate the expression of secreted proteins involved in different cardiac development processes. NOTCH signaling activation correlates with a transforming growth factor-ß2 (TGFß2)-rich secretome and the delivery of paracrine signals involved in focal adhesion and extracellular matrix (ECM) deposition and remodeling. In contrast, NOTCH inhibition is accompanied by the up-regulation of specific semaphorins that may modulate cell migration. The secretome protein expression data showed a good correlation with gene profiling of RNA expression in embryonic endocardial cells. Additional characterization by in situ hybridization in mouse embryos revealed expression of various NOTCH candidate effector genes (Tgfß2, Loxl2, Ptx3, Timp3, Fbln2, and Dcn) in heart valve endocardium and/or mesenchyme. Validating these results, mice with conditional Dll4 or Jag1 loss-of-function mutations showed gene expression alterations similar to those observed at the protein level in vitro These results provide the first description of the NOTCH-dependent endocardial secretome and validate MEEC as a tool for assaying the endocardial secretome response to a variety of stimuli and the potential use of this system for drug screening.

Measurement of Disease Activity in Ecuadorian Patients with Rheumatoid Arthritis: Does RAPID3 Correlate with Traditional Indexes?

OBJECTIVE: The aim of this study is to demonstrate if routine assessment of patient index data 3 has a correlation with disease's activity as much as disease activity score 28, clinical disease activity index, and simplified disease activity index in Ecuadorian patients with rheumatoid arthritis seen in Unidad de Enfermedades Reumáticas y Autoinmunes [UNERA] from December 2016 to December 2017. METHODS: This is a retrospective study in 200 patients that fulfill the American College of Rheumatology 2010 criteria for diagnosis of rheumatoid arthritis. The patients were evaluated from December 2016 to December 2017. Descriptive analyses were carried out, also Pearson correlation was used, and, to give a better clinical significance, a chi-square test was conducted. Whenever assumptions of chi-square test were violated, a Fisher's exact test was reported. RESULTS: RAPID3 correlated best with DAS28 (r.83, p < 0.001), followed by CDAI (r.80, p < 0.001) and then SDAI (r.77, p < 0.001). CONCLUSION: RAPID3 is a questionnaire that only takes 10 seconds to calculate and correlates in a significant way with traditional clinical measures that require more time to perform, saving time in busy health facilities.

Evolutionarily conserved Tbx5-Wnt2/2b pathway orchestrates cardiopulmonary development.

Codevelopment of the lungs and heart underlies key evolutionary innovations in the transition to terrestrial life. Cardiac specializations that support pulmonary circulation, including the atrial septum, are generated by second heart field (SHF) cardiopulmonary progenitors (CPPs). It has been presumed that transcription factors required in the SHF for cardiac septation, e.g., Tbx5, directly drive a cardiac morphogenesis gene-regulatory network. Here, we report instead that TBX5 directly drives Wnt ligands to initiate a bidirectional signaling loop between cardiopulmonary mesoderm and the foregut endoderm for endodermal pulmonary specification and, subsequently, atrial septation. We show that Tbx5 is required for pulmonary specification in mice and amphibians but not for swim bladder development in zebrafish. TBX5 is non-cell-autonomously required for pulmonary endoderm specification by directly driving Wnt2 and Wnt2b expression in cardiopulmonary mesoderm. TBX5 ChIP-sequencing identified cis-regulatory elements at Wnt2 sufficient for endogenous Wnt2 expression domains in vivo and required for Wnt2 expression in precardiac mesoderm in vitro. Tbx5 cooperated with Shh signaling to drive Wnt2b expression for lung morphogenesis. Tbx5 haploinsufficiency in mice, a model of Holt-Oram syndrome, caused a quantitative decrement of mesodermal-to-endodermal Wnt signaling and subsequent endodermal-to-mesodermal Shh signaling required for cardiac morphogenesis. Thus, Tbx5 initiates a mesoderm-endoderm-mesoderm signaling loop in lunged vertebrates that provides a molecular basis for the coevolution of pulmonary and cardiac structures required for terrestrial life.

Bmp2 and Notch cooperate to pattern the embryonic endocardium.

Signaling interactions between the myocardium and endocardium pattern embryonic cardiac regions, instructing their development to fulfill specific functions in the mature heart. We show that ectopic Bmp2 expression in the mouse chamber myocardium changes the transcriptional signature of adjacent chamber endocardial cells into valve tissue, and enables them to undergo epithelial-mesenchyme transition. This induction is independent of valve myocardium specification and requires high levels of Notch1 activity. Biochemical experiments suggest that Bmp2-mediated Notch1 induction is achieved through transcriptional activation of the Notch ligand Jag1, and physical interaction of Smad1/5 with the intracellular domain of the Notch1 receptor. Thus, widespread myocardial Bmp2 and endocardial Notch signaling drive presumptive ventricular endocardium to differentiate into valve endocardium. Understanding the molecular basis of valve development is instrumental to designing therapeutic strategies for congenital heart valve defects.

Sjögren's Syndrome Associated with Fanconi's Syndrome and Osteomalacia.

BACKGROUND Sjögren's syndrome is a chronic inflammatory autoimmune disease, which is also known as sicca syndrome, due to the symptoms of dry eyes and dry mouth, and is associated with other connective tissue diseases and autoimmune diseases. Sjögren's syndrome can also be associated with renal involvement. Fanconi's syndrome is associated with impaired reabsorption in the proximal renal tubule associated with tubulointerstitial nephritis and is associated with renal tubular acidosis and hypophosphatemia. Osteomalacia is a rare association with Sjögren's syndrome, which may result from renal disease. CASE REPORT We report the case of a 34-year-old woman who presented with xerostomia, xerophthalmia, bone fractures, and osteomuscular pain. A Schirmer test showed reduced tear production, and a biopsy of a minor salivary gland of the lip, with high titers of antinuclear antibodies (ANA), and positive anti-SSA/Ro and anti-SSB/La antibodies confirmed the diagnosis of Sjögren's syndrome. Serum and urinary laboratories tests and clinical manifestations confirmed Fanconi's syndrome associated with osteomalacia. The patient was treated with potassium supplements, 25-hydroxyvitamin D (25(OH)D), hydroxychloroquine, mycophenolate mofetil, and prednisone, with a favorable response. CONCLUSIONS This case is of a rare association between Sjögren's syndrome, Fanconi's syndrome, and osteomalacia. Even though these are rare clinical associations, early detection can improve the quality of life and prevent further complications.

A combined linkage and association strategy identifies a variant near the GSTP1 gene associated with BMI in the Mexican population.

Obesity is a major public health concern in Mexico and worldwide. Although the estimated heritability is high, common variants identified by genome-wide association studies explain only a small proportion of this heritability. A combination of linkage and association strategies could be a more robust and powerful approach to identify other obesity-susceptibility variants. We thus sought to identify novel genetic variants associated with obesity-related traits in the Mexican population by combining these methods. We performed a genome-wide linkage scan for body mass index (BMI) and other obesity-related phenotypes in 16 Mexican families using the Sequential Oligogenic Linkage Analysis Routines Program. Associated single-nucleotide polymorphisms (SNPs) were tested for associations in an independent cohort. Two suggestive BMI-linkage peaks (logarithm of odds ⩾1.5) were observed at chromosomal regions 11q13 and 13q22. Only rs614080 in the 11q13 region was significantly associated with BMI and related traits in these families. This association was also significant in an independent cohort of Mexican adults. Moreover, this variant was significantly associated with GSTP1 gene expression levels in adipose tissue. In conclusion, the rs614080 SNP near the GSTP1 gene was significantly associated with BMI and GSTP1 expression levels in the Mexican population.

Complex Interdependence Regulates Heterotypic Transcription Factor Distribution and Coordinates Cardiogenesis.

Transcription factors (TFs) are thought to function with partners to achieve specificity and precise quantitative outputs. In the developing heart, heterotypic TF interactions, such as between the T-box TF TBX5 and the homeodomain TF NKX2-5, have been proposed as a mechanism for human congenital heart defects. We report extensive and complex interdependent genomic occupancy of TBX5, NKX2-5, and the zinc finger TF GATA4 coordinately controlling cardiac gene expression, differentiation, and morphogenesis. Interdependent binding serves not only to co-regulate gene expression but also to prevent TFs from distributing to ectopic loci and activate lineage-inappropriate genes. We define preferential motif arrangements for TBX5 and NKX2-5 cooperative binding sites, supported at the atomic level by their co-crystal structure bound to DNA, revealing a direct interaction between the two factors and induced DNA bending. Complex interdependent binding mechanisms reveal tightly regulated TF genomic distribution and define a combinatorial logic for heterotypic TF regulation of differentiation.

Taste and Olfactory Changes Following Laparoscopic Gastric Bypass and Sleeve Gastrectomy.

BACKGROUND: Alterations in taste/smell after bariatric surgery have been observed, but few data is available. Some authors documented these changes and their role on weight loss but there is no evidence after laparoscopic sleeve gastrectomy (LSG). METHODS: Cohort study with patients submitted to laparoscopic gastric bypass (LGBP) and LSG that were asked to participate in a validated survey. The primary objective was to determinate the differences between procedures for taste and smell changes; a demographic and anthropometric analysis were also performed. Secondarily, the relation between food aversion and weight loss was also obtained. RESULTS: Final analysis was based on 154 patients (104 LGBP and 50 LSG). The overall mean time between surgery and questionnaire was 10 ± 6.7 months. Most of the patients (87.6 %) experienced some taste/smell change. There were no differences between procedures for any change, taste or smell change. More patients submitted to LGBP referred that food smelled different (51.9 vs 34 % for the LSG group; p = 0.040). Higher %EWL was observed for patients presenting food aversion (73.3 ± 19.7 vs 65.8 ± 19.4 % for those without aversion; p = 0.046). Based on type of surgery, the LGBP group had the same trend (%EWL of 78.2 ± 17.3 vs 70.4 ± 18.6 % for those without aversion; p = 0.044). CONCLUSION: The majority of patients presented taste and olfactory changes soon after surgery independently of type of procedure. Patients submitted to LGBP referred more often a different smell in food. Higher %EWL was observed in patients presenting any food aversion, especially in the LGBP group.

Blood SC5b-9 complement levels increase at parturition during term and preterm labor.

We explored the hypothesis that complement, an innate and adaptive immune effector, is active in the plasma of parturient women and is deposited on fetal membranes collected after delivery. A cross-sectional study was designed to evaluate complement activity at parturition. Pregnant women (n = 97) between 15 and 41 years of age were enrolled in a hospital protocol during the perinatal period to assess both SC5b-9 complement activity in blood and complement deposition on fetal membranes during parturition. Soluble SC5b-9 complement activity in plasma fractions was measured using a standard enzyme-linked immunosorbent assay (ELISA) that included specific anti-complement antibodies. Complement deposition on membranes was analyzed using immuno-dot blots and immunohistochemistry. Soluble SC5b-9 complement complex levels were increased in the plasma of women during term labor (TL; median 3361; range 1726-5670 ng/mL), preterm labor (PL; median 2958; range 1552-7092 ng/mL), and preterm premature rupture of membranes (PPROM; median 2272; range 167-6540 ng/mL) compared with pregnant women who were not in labor (P; median 1384; range 174-4570 ng/mL; P < 0.001, Kruskal-Wallis test). Active complement, as assessed by the C9 neo-antigen in C5b-9 complexes, was deposited on fetal membranes, with no difference between term and preterm delivery. The deposition of active complement on fetal membranes was confirmed by immunohistochemistry. Women who underwent non-labor-indicated Cesarean sections did not exhibit complement deposition. Soluble SC5b-9 complement complex levels increased in the plasma of women during parturition, and complement C5b-9 complexes were deposited on fetal membranes.

10-year outcomes of the vertical transected gastric bypass for obesity: a systematic review.

With increasing worldwide obesity rates, the surgery of choice has become the vertical transected gastric bypass, showing short-term improvements in weight loss and comorbidities. However, corresponding 10-year data regarding such endpoints is limited. The objective of this review was to assess such evidence. A literature search yielded a total of five studies, of which three had extractable data. Results revealed a reduction in the weighted mean body mass index (BMI), from a pre- to post-operative mean BMI of 47.5 kg/m(2) ± 2.0 to 33.4 kg/m(2) ± 4.4 at 10 years. The weighted mean excess weight loss was 61.4 % ± 13.5. Although these results suggest that weight reduction may be sustainable in the long term, this systematic review demonstrates a lack of strong evidence to support favorable long-term outcomes following vertical transected gastric bypass for obesity.

Chromatin modulators as facilitating factors in cellular reprogramming.

In the last few years, cellular reprogramming has emerged as a means to alter cellular identity and generate diverse cell types for disease modeling, drug testing, and potential therapeutic use. Since each cell type is a result of a specific gene expression profile finely regulated by the activity of a repertoire of transcription factors (TFs), reprogramming approaches have, thus far, been relatively inefficient and based largely on the forced expression of selective cell type-specific TFs. TFs function within the confines of chromatin, and the chromatin states can in turn be modulated by TF activity. Therefore, the knowledge of how chromatin remodeling factors alter chromatin structure, control TF activity and gene expression has led to an improved reprogramming efficiency and extended the number of cellular types that can be generated by cellular reprogramming. Here we review recent insights into the role and mechanisms by which chromatin remodeling, histone modifications, and DNA methylation contribute to cellular differentiation and reprogramming.

Epithelial to mesenchymal transition-the roles of cell morphology, labile adhesion and junctional coupling.

Epithelial to mesenchymal transition (EMT) is a fundamental process during development and disease, including development of the heart valves and tumour metastases. An extended cellular Potts model was implemented to represent the behaviour emerging from autonomous cell morphology, labile adhesion, junctional coupling and cell motility. Computer simulations normally focus on these functional changes independently whereas this model facilitates exploration of the interplay between cell shape changes, adhesion and migration. The simulation model is fitted to an in vitro model of endocardial EMT, and agrees with the finding that Notch signalling increases cell-matrix adhesion in addition to modulating cell-cell adhesion.

Notch signaling in cardiac valve development and disease.

The Notch pathway is an intercellular signaling mechanism involved in multiple cell-to-cell communication processes that regulate cell fate specification, differentiation, and tissue patterning during embryogenesis and adulthood. Functional studies in the mouse have shown that a Hey-Bmp2 regulatory circuit restricts Bmp2 expression to presumptive valve myocardium (atrioventricular canal and outflow tract). Likewise, a Notch-Hey-Bmp2 axis represses Bmp2 in the endocardium. During cardiac valve formation, endocardial Notch signaling activates the epithelial-mesenchyme transition (EMT) that will give rise to the cardiac valve primordia. During this process, Notch integrates with myocardially derived signals (Bmp2 or Bmp4) to promote, via Snail1/2 activation a complete, invasive EMT in presumptive valve tissue. In humans, mutations in Notch signaling components are associated with several congenital disorders involving malformed valves, aortic arch, and defective chamber septation. Data suggest that the same embryonic Notch-Hey-Bmp2 regulatory axis is active in the adult valve. This review examines the experimental evidence supporting a role for Notch in heart valve development and homeostasis, and how altered Notch signaling may lead to valve disease in the newborn and adult.

Integration of a Notch-dependent mesenchymal gene program and Bmp2-driven cell invasiveness regulates murine cardiac valve formation.

Cardiac valve formation is crucial for embryonic and adult heart function. Valve malformations constitute the most common congenital cardiac defect, but little is known about the molecular mechanisms regulating valve formation and homeostasis. Here, we show that endocardial Notch1 and myocardial Bmp2 signal integration establish a valve-forming field between 2 chamber developmental domains. Patterning occurs through the activation of endocardial epithelial-to-mesenchymal transition (EMT) exclusively in prospective valve territories. Mice with constitutive endocardial Notch1 activity ectopically express Hey1 and Heyl. They also display an activated mesenchymal gene program in ventricles and a partial (noninvasive) EMT in vitro that becomes invasive upon BMP2 treatment. Snail1, TGF-ß2, or Notch1 inhibition reduces BMP2-induced ventricular transformation and invasion, whereas BMP2 treatment inhibits endothelial Gsk3ß, stabilizing Snail1 and promoting invasiveness. Integration of Notch and Bmp2 signals is consistent with Notch1 signaling being attenuated after myocardial Bmp2 deletion. Notch1 activation in myocardium extends Hey1 expression to nonchamber myocardium, represses Bmp2, and impairs EMT. In contrast, Notch deletion abrogates endocardial Hey gene transcription and extends Bmp2 expression to the ventricular endocardium. This embryonic Notch1-Bmp2-Snail1 relationship may be relevant in adult valve disease, in which decreased NOTCH signaling causes valve mesenchyme cell formation, fibrosis, and calcification.

The administration of low doses of rituximab followed by hydroxychloroquine, prednisone and low doses of mycophenolate mofetil is an effective therapy in Latin American patients with active systemic lupus erythematosus.

BACKGROUND: In Latin America, the medical attention directed to systemic autoimmune diseases competes with a budget designed to fight poverty, lack of education, etc. In this context, the access to treatments recommended internationally are expensive and limited; therefore, research of methods that make these treatments cheaper is of paramount importance. OBJECTIVE: Our objective was to describe the 24-month clinical outcome of patients with active systemic lupus erythematosus (SLE) who received low doses of rituximab (RTX), followed by hydroxychloroquine (HCQ), prednisone and low doses of mycophenolate mofetil (MMF). METHODS: Forty-six patients with active SLE received 500 mg of RTX (together with 500 mg of methylprednisolone as a premedication) administered on two occasions 2 weeks apart, followed by HCQ (200-400 mg/day), prednisone and MMF (500-1000 mg/day) during a 24-month follow-up period. Clinical outcome was assessed using the MEX-SLE Disease Activity Index (MEX-SLEDAI) and serial serologic measurements. Remission was defined as MEX-SLEDAI scores 0-1, mild disease activity 2-5, moderate disease activity 6-9, severe 10-13, and very severe 14 or more. RESULTS: Disease activity decreased over time with treatment. At baseline, 19 (41.3%) patients had very severe, 16 (34.8%) severe, and 9 (19.6%) moderate disease activity. Improvement on disease activity was detected at 3 months, since 9 (19.6%) patients reached disease remission after this period of time and remission increased to 16 (34.8%) patients at 6 months, 19 (41.3%) at 1 year, and 23 (50%) at 2 years of follow-up (p<0.0001). CONCLUSION: The administration of low doses of RTX followed by HCQ, prednisone and low doses of MMF is an effective therapy in Latin American patients with active SLE.

Should rituximab be considered as the first-choice treatment for severe autoimmune rheumatic diseases?

The present study aimed to assess the tolerance and efficacy of rituximab (RTX), a chimeric IgG1 monoclonal antibody directed against the CD20 receptor present in B lymphocytes, in patients with autoimmune rheumatic diseases (AIRD). For this purpose, patients treated with RTX and their respective clinical charts were comprehensively examined. Indications for treatment were a refractory character of the disease, inefficacy or intolerance of other immunosuppressors. Activity indexes (SLEDAI, DAS28, and specific clinical manifestations) were used to evaluate efficacy. Serious side effects were also recorded. Seventy-four patients were included. Forty-three patients had systemic lupus erythematosus (SLE), 21 had rheumatoid arthritis (RA), 8 had Sjögren's syndrome (SS), and 2 had Takayasu's arteritis (TA). RTX was well-tolerated in 66 (89%) patients. In 8 patients (SLE=3, SS=3, RA=2), serious side effects lead to discontinuation. The mean follow-up period was 12+/-7.8 (2-35) months. The efficacy of RTX was registered in 58/66 (87%) patients, of whom 36 (83%) had SLE, 18/21 (85%) had RA, 3/8 (37%) had SS, and 1 had TA. The mean time of efficacy was 6.3+/-5.1 weeks. A significant steroid-sparing effect was noticed in half of the patients. These results add further evidence for the use of RTX in AIRD. Based on its risk-benefit ratio, RTX might be used as the first-choice treatment for patients with severe AIRD.