Dual ifgMosaic: A Versatile Method for Multispectral and Combinatorial Mosaic Gene-Function Analysis.

Improved methods for manipulating and analyzing gene function have provided a better understanding of how genes work during organ development and disease. Inducible functional genetic mosaics can be extraordinarily useful in the study of biological systems; however, this experimental approach is still rarely used in vertebrates. This is mainly due to technical difficulties in the assembly of large DNA constructs carrying multiple genes and regulatory elements and their targeting to the genome. In addition, mosaic phenotypic analysis, unlike classical single gene-function analysis, requires clear labeling and detection of multiple cell clones in the same tissue. Here, we describe several methods for the rapid generation of transgenic or gene-targeted mice and embryonic stem (ES) cell lines containing all the necessary elements for inducible, fluorescent, and functional genetic mosaic (ifgMosaic) analysis. This technology enables the interrogation of multiple and combinatorial gene function with high temporal and cellular resolution.

Microglia regulate central nervous system myelin growth and integrity.

Myelin is required for the function of neuronal axons in the central nervous system, but the mechanisms that support myelin health are unclear. Although macrophages in the central nervous system have been implicated in myelin health1, it is unknown which macrophage populations are involved and which aspects they influence. Here we show that resident microglia are crucial for the maintenance of myelin health in adulthood in both mice and humans. We demonstrate that microglia are dispensable for developmental myelin ensheathment. However, they are required for subsequent regulation of myelin growth and associated cognitive function, and for preservation of myelin integrity by preventing its degeneration. We show that loss of myelin health due to the absence of microglia is associated with the appearance of a myelinating oligodendrocyte state with altered lipid metabolism. Moreover, this mechanism is regulated through disruption of the TGFß1-TGFßR1 axis. Our findings highlight microglia as promising therapeutic targets for conditions in which myelin growth and integrity are dysregulated, such as in ageing and neurodegenerative disease2,3.

Arterialization requires the timely suppression of cell growth.

The formation of arteries is thought to occur by the induction of a highly conserved arterial genetic programme in a subset of vessels that will later experience an increase in oxygenated blood flow1,2. The initial steps of arterial specification require both the VEGF and Notch signalling pathways3-5. Here, we combine inducible genetic mosaics and transcriptomics to modulate and define the function of these signalling pathways in cell proliferation, arteriovenous differentiation and mobilization. We show that endothelial cells with high levels of VEGF or Notch signalling are intrinsically biased to mobilize and form arteries; however, they are not genetically pre-determined, and can also form veins. Mechanistically, we found that increased levels of VEGF and Notch signalling in pre-arterial capillaries suppresses MYC-dependent metabolic and cell-cycle activities, and promotes the incorporation of endothelial cells into arteries. Mosaic lineage-tracing studies showed that endothelial cells that lack the Notch-RBPJ transcriptional activator complex rarely form arteries; however, these cells regained the ability to form arteries when the function of MYC was suppressed. Thus, the development of arteries does not require the direct induction of a Notch-dependent arterial differentiation programme, but instead depends on the timely suppression of endothelial cell-cycle progression and metabolism, a process that precedes arterial mobilization and complete differentiation.

iSuRe-HadCre is an essential tool for effective conditional genetics.

Methods for modifying gene function at high spatiotemporal resolution in mice have revolutionized biomedical research, with Cre-loxP being the most widely used technology. However, the Cre-loxP technology has several drawbacks, including weak activity, leakiness, toxicity, and low reliability of existing Cre-reporters. This is mainly because different genes flanked by loxP sites (floxed) vary widely in their sensitivity to Cre-mediated recombination. Here, we report the generation, validation, and utility of iSuRe-HadCre, a new dual Cre-reporter and deleter mouse line that avoids these drawbacks. iSuRe-HadCre achieves this through a novel inducible dual-recombinase genetic cascade that ensures that cells expressing a fluorescent reporter had only transient Cre activity, that is nonetheless sufficient to effectively delete floxed genes. iSuRe-HadCre worked reliably in all cell types and for the 13 floxed genes tested. This new tool will enable the precise, efficient, and trustworthy analysis of gene function in entire mouse tissues or in single cells.

Pediatric kidney dimensions and risk of persistent albuminuria in Mexican adolescents.

In Mexico, chronic kidney disease of unknown origin is highly prevalent. Screening studies in adolescents have shown persistent microalbuminuria (pACR), adaptive podocytopathy and decreased kidney volume (KV). Here, we sought to develop normality tables of kidney dimensions by ultrasound in the Mexican state of Aguascalientes pediatric population (0 to 18y) and evaluate the relationship between the KV and pACR among the region's adolescents in a cross-sectional study. Kidney length (KL) and KV were determined by ultrasound. Our findings were compared with those in international literature of different populations where tables and graphs of normal kidney dimensions by ultrasound were reported. We compared organ dimensions in individuals above the age of 11 without albuminuria with those in patients with pACR recruited through screening studies in adolescents in Aguascalientes. This included 1068 individuals to construct percentile tables and graphs of the KL. Kidney dimensions were significantly lower when compared with all international comparisons. From a total 14,805 screen individuals, we compared 218 adolescents with pACR and 377 individuals without significant albuminuria. The Total KV adjusted to body surface (TKVBS) was significantly associated with pACR (odds ratio 1.03, 95% confidence interval 1.02-1.03). The upper quartile of TKVBS was highly associated with pACR (7.57, 4.13-13.87), hypertension (2.53, 1.66-3.86), and hyperfiltration (26 vs 11.5%). Thus, TKVBS is directly associated with pACR while greater KV, arterial hypertension, and hyperfiltration in patients with pACR suggest that the increase in volume is secondary to kidney hypertrophy. Additionally, the adaptative podocytopathy with low fibrosis seen on kidney biopsy which was performed in a subset of patients, and the smaller kidney dimensions in our population point to prenatal oligonephronia as the primary cause of the detected kidney disease.

Does remission in systemic lupus erythematosus according to the 2021 DORIS definition match the treating rheumatologist's judgement?

OBJECTIVES: To assess agreement between the 2021 Definition Of Remission In SLE (DORIS) and physician-judged lupus activity. METHODS: A cross-sectional analysis was conducted of data from a Spanish prospective multicentre study of SLE patients. We applied the 2021 DORIS criteria and assessed whether remission status based on this definition agreed with remission as per physician clinical judgement and reasons for disagreement between them. RESULTS: Out of 508 patients [92% women; mean age (s.d.): 50.4 years (13.7)] studied, 267 (54.4%) met the criteria for 2021 DORIS remission. Based on physicians' judgement, 277 (55.9%) patients were classified as in remission or serologically active clinically quiescent (SACQ). The overall rate of agreement between these assessments was 81.2% (95% CI: 79.9, 82.9%) with a Cohen's kappa of 0.62 (0.55-0.69). Overall, 46 (9.1%) patients were classified as in remission/SACQ by rheumatologists but did not meet the 2021 DORIS criteria for remission. The main reasons for discrepancies were a clinical SLE Disease Activity Index (cSLEDAI) score >0 in 39 patients, a Physician Global Assessment score >0.5 in five patients, and prednisone >5 mg/day in another five patients. CONCLUSIONS: The 2021 DORIS remission is an achievable target in clinical practice. There is substantial agreement between the DORIS definition and physician-judged remission. The discordance was mainly due to physicians classifying some patients with ongoing mild disease activity as in remission. Thus, the standardized DORIS definition should be used to define the target in a treat-to-target strategy for the management of SLE.

Thorough assessment of the effectiveness of belimumab in a large Spanish multicenter cohort of systemic lupus erythematosus patients.

OBJECTIVES: To provide an overview on the current use of belimumab (BLM) in SLE patients in clinical practice and to examine its efficacy in terms of standardized outcomes, drug survival, as well as patient and safety profiles. METHODS: A longitudinal retrospective multicentre cohort including SLE patients treated with BLM at 18 Spanish centers. Data was collected upon initiation of BLM, at 6 and 12 months after initiation, and at the last recorded visit. Changes in SLEDAI-2K, the proportion of patients who achieved LLDAS and DORIS 2021, and number of flares were compared between visits. Changes in damage, glucocorticoids use and employment status pre-BLM and post-BLM were also assessed. RESULTS: A total of 324 patients were included with a mean follow-up of 3.8 (±2.7) years. LLDAS was attained by 45.8%, 62% and 71% of patients, and DORIS by 24%, 36.2% and 52.5% on successive visits, respectively. Twenty-seven-point two percent of patients were in DORIS ≥ 50% of the visits and a 46% in LLDAS-50. Flares and number of flares were significantly lower one year after treatment with BLM and no changes in damage accrual were observed. Mean (±SD) prednisone dose was significantly reduced over time, with 70 (24%) patients discontinuing GC. CONCLUSION: Our study not only demonstrates belimumab´s efficacy in attaining treat-to-target goals in SLE patients, but also confirms its GC-sparing effect, and its prevention of flares and organ damage accrual.

High-Mannose Oligosaccharide Hemimimetics that Recapitulate the Conformation and Binding Mode to Concanavalin A, DC-SIGN and Langerin.

The "carbohydrate chemical mimicry" exhibited by sp2 -iminosugars has been utilized to develop practical syntheses for analogs of the branched high-mannose-type oligosaccharides (HMOs) Man3 and Man5 . In these compounds, the terminal nonreducing Man residues have been substituted with 5,6-oxomethylidenemannonojirimycin (OMJ) motifs. The resulting oligomannoside hemimimetic accurately reproduce the structure, configuration, and conformational behavior of the original mannooligosaccharides, as confirmed by NMR and computational techniques. Binding studies with mannose binding lectins, including concanavalin A, DC-SIGN, and langerin, by enzyme-linked lectin assay and surface plasmon resonance revealed significant variations in their ability to accommodate the OMJ unit in the mannose binding site. Intriguingly, OMJMan segments demonstrated "in line" heteromultivalent effects during binding to the three lectins. Similar to the mannobiose (Man2 ) branches in HMOs, the binding modes involving the external or internal monosaccharide unit at the carbohydrate binding-domain exist in equilibrium, facilitating sliding and recapture processes. This equilibrium, which influences the multivalent binding of HMOs, can be finely modulated upon incorporation of the OMJ sp2 -iminosugar caps. As a proof of concept, the affinity and selectivity towards DC-SIGN and langerin were adjustable by presenting the OMJMan epitope in platforms with diverse architectures and valencies.

Does expert opinion match the definition of lupus low disease activity state? Prospective analysis of 500 patients from a Spanish multicentre cohort.

OBJECTIVES: To apply the lupus low disease activity state (LLDAS) definition within a large cohort of patients and to assess the agreement between the LLDAS and the physician's subjective evaluation of lupus activity. METHODS: We conducted a cross-sectional analysis of a prospective multicentre study of SLE patients. We applied the LLDAS and assessed whether there was agreement with the clinical status according to the physician's opinion. RESULTS: A total of 508 patients [92% women; mean age 50.4 years (s.d. 3.7)] were recruited and 304 (62.7%) patients were in the LLDAS. According to physician assessment, 430 (86.1%) patients were classified as remission or low activity. Overall agreement between both evaluations was 71.4% (95% CI: 70.1, 70.5) with a Cohen's κ of 0.3 [interquartile range (IQR) 0.22-0.37]. Most cases (96.1%) in the LLDAS were classified as remission or low activity by the expert. Of the patients who did not fulfil the LLDAS, 126 (70.4%) were classified as having remission/low disease activity. The main reasons for these discrepancies were the presence of new manifestations compared with the previous visit and a SLEDAI 2K score >4, mainly based on serological activity. CONCLUSIONS: Almost two-thirds of SLE patients were in the LLDAS. There was a fair correlation between the LLDAS and the physician's evaluation. This agreement improves for patients fulfilling the LLDAS criteria. The discordance between both at defining lupus low activity, the demonstrated association of the LLDAS with better outcomes and the fact that the LLDAS is more stringent than the physician's opinion imply that we should use the LLDAS as a treat-to-target goal.

Community-wide correlations between species richness, abundance and population genomic diversity in a freshwater biodiversity hotspot.

Understanding patterns of diversity across macro (e.g. species-level) and micro (e.g. molecular-level) scales can shed light on community function and stability by elucidating the abiotic and biotic drivers of diversity within ecological communities. We examined the relationships among taxonomic and genetic metrics of diversity in freshwater mussels (Bivalvia: Unionidae), an ecologically important and species-rich group in the southeastern United States. Using quantitative community surveys and reduced-representation genome sequencing across 22 sites in seven rivers and two river basins, we surveyed 68 mussel species and sequenced 23 of these species to characterize intrapopulation genetic variation. We tested for the presence of species diversity-abundance correlations (i.e. the more-individuals hypothesis, MIH), species-genetic diversity correlations (SGDCs) and abundance-genetic diversity correlations (AGDCs) across all sites to evaluate relationships between different metrics of diversity. Sites with greater cumulative multispecies density (a standardized metric of abundance) had a greater number of species, consistent with the MIH hypothesis. Intrapopulation genetic diversity was strongly associated with the density of most species, indicating the presence of AGDCs. However, there was no consistent evidence for SGDCs. Although sites with greater overall densities of mussels had greater species richness, sites with higher genetic diversity did not always exhibit positive correlations with species richness, suggesting that there are spatial and evolutionary scales at which the processes influencing community-level diversity and intraspecific diversity differ. Our work reveals the importance of local abundance as indicator (and possibly a driver) of intrapopulation genetic diversity.

Cytomegalovirus drug resistance mutations in transplant recipients with suspected resistance.

Resistant CMV infections are challenging complications after SOT and HSCT. Prompt recognition of ARMs is imperative for appropriate therapy. 108 plasma samples from 96 CMV + transplant recipients with suspected resistance were analysed in CNM in a retrospective nationwide study from January 2018 to July 2022 for resistance genotyping. ARMs in UL97 and UL54 were found in 26.87% (18/67) and 10.60% (7/66) of patients, respectively. Patients' ARM distribution in UL97 was as follows: L595S n = 3; L595S/M460I n = 1; L595S/N510S n = 1; L595W n = 1; C603W n = 4; A594V n = 3; A594E n = 1; C607Y n = 1; L397R/T409M/H411L/M460I n = 1; L397I n = 1; H520Q n = 1; four patients showed ARMs in UL54 as well (F412C n = 1; T503I n = 2; P522S n = 1), whereas three patients exhibited ARMs in UL54 only (L501I/T503I/L516R/A834P n = 1; A987G n = 2). L516R in UL54 and L397R/I and H411L in UL97 have been found for the first time in a clinical sample. L595S/W was the most prevalent ARM found to lend resistance to GCV. In UL54 all ARMs lent resistance to GCV and CDV. In addition, A834P, found in one patient, also lent resistance to FOS. CMV load did not differ significantly in patients with or without ARMs, and no differences were found either between patients with ARMs in UL97 or in UL97 and UL54. Despite extensive use of classical antivirals for the treatment of CMV infection after HSCT and SOT, ARMs occurred mainly in viral UL97 kinase, which suggests that CDV and mostly FOS continue to be useful alternatives to nucleoside analogues after genotypic detection of ARMs.

Coping with multiple sclerosis: reconciling significant aspects of health-related quality of life.

Multiple sclerosis (MS) symptoms and unpredictability can damage patient well-being. This study is aimed to investigate the relation between sociodemographic and clinical characteristics and the use of coping strategies as well as social support on health-related quality of life (HRQOL). We evaluated 314 MS outpatients of Virgen Macarena University Hospital in Sevilla/Spain (mean age 45 years, 67.8% women) twice over an 18-months period by Brief COPE Questionnaire (COPE-28), Multidimensional Scale of Perceived Social Support (MSPSS) and 12-Item Short Form Health Survey (SF-12). Female gender was significantly related to religion (r= 0.175, p< 0.001), self-distraction (r= 0.160, p< 0.001) and self-blame (r= 0.131, p< 0.05). Age correlated positively with religion (r= 0.240, p< 0.001), and self-blame (r= 0.123, p< 0.05). Progressive MS as well as functional impairment (EDSS) showed a positive relation with denial (r= 0.125, p< 0.05; r= 0.150, p< 0.001). Longer duration since diagnosis was related to lower perceived support from family (r= -0.123, p< 0.05). EDSS (ß= -0.452, p< 0.001) was the strongest negative predictor of physical HRQOL followed by age (ß= -0.123, p< 0.001), whereas family support was a protective factor (ß= 0.096, p< 0.001). Denial (ß= -0.132, p< 0.05), self-blame (ß= -0.156, p< 0.05), female gender (ß= -0.115, p< 0.05) and EDSS (ß= -0.108, p< 0.05) negatively impacted on mental HRQOL 18 months later, whereas positive reframing (ß= 0.142, p< 0.05) was a protective factor. Our study could identify sociodemographic and clinical variables associated with dysfunctional coping strategies, such as self-blame and denial, which specifically predict worse mental HRQOL as opposed to positive reframing. Diminishing dysfunctional coping and supporting cognitive reframing may contribute to improve HRQOL in MS.

A Functional Pipeline of Genome-Wide Association Data Leads to Midostaurin as a Repurposed Drug for Alzheimer's Disease.

Genome-wide association studies (GWAS) constitute a powerful tool to identify the different biochemical pathways associated with disease. This knowledge can be used to prioritize drugs targeting these routes, paving the road to clinical application. Here, we describe DAGGER (Drug Repositioning by Analysis of GWAS and Gene Expression in R), a straightforward pipeline to find currently approved drugs with repurposing potential. As a proof of concept, we analyzed a meta-GWAS of 1.6 × 107 single-nucleotide polymorphisms performed on Alzheimer's disease (AD). Our pipeline uses the Genotype-Tissue Expression (GTEx) and Drug Gene Interaction (DGI) databases for a rational prioritization of 22 druggable targets. Next, we performed a two-stage in vivo functional assay. We used a C. elegans humanized model over-expressing the Aß1-42 peptide. We assayed the five top-scoring candidate drugs, finding midostaurin, a multitarget protein kinase inhibitor, to be a protective drug. Next, 3xTg AD transgenic mice were used for a final evaluation of midostaurin's effect. Behavioral testing after three weeks of 20 mg/kg intraperitoneal treatment revealed a significant improvement in behavior, including locomotion, anxiety-like behavior, and new-place recognition. Altogether, we consider that our pipeline might be a useful tool for drug repurposing in complex diseases.

Intestinal obstruction due to pneumatosis intestinalis.

We present the case of an 83-year-old male, with a past medical history of benign pneumoperitoneum secondary to pneumatosis intestinalis which evolved for a number of years with periodic follow-ups. The patient comes to the Emergency Room with sintomatology of intestinal obstruction. Urgent surgical management is decided, an exploratory laparotomy is performed where an intestinal obstruction secondary to pneumatosis intestinalis, with loss of structure of the intestinal wall as visualized in the images, is determined; therefore resection of the affected small intestine segment and primary anastomosis are performed. The pathology report confirms the diagnosis. The patient progresses favorably during the postoperative period and is currently asymptomatic after 12 months.

HLA-E restricted cytomegalovirus UL40 peptide polymorphism may represent a risk factor following congenital infection.

BACKGROUND: Congenital cytomegalovirus immunopathogenesis is largely unknown and multifactorial due to the complex interactions between viral, maternal, placental, and child factors. Polymorphisms in the HLA-E binding UL4015-23 peptide mimics HLA-E complexed peptides from certain HLA-A, -B, -C and -G alleles, which regulate the cellular immune response driven by natural killer-cells (NK) and CD8 + T cells. The aim of this study was to compare UL4015-23 peptides distribution in congenital CMV and the counterpart HLA Class I peptides in a healthy cohort to investigate risk factors and markers for cCMV disease. In this 10-year retrospective study, the UL40 gene was directly sequenced from 242 clinical samples from 199 cases of congenital CMV (166 children and 33 pregnant or breast feeding women). Distribution of HLA-E binding UL4015-23 peptides was analyzed and compared to those of HLA Class I observed in a cohort of 444 healthy individuals. RESULTS: Nineteen different HLA-E binding UL4015-23 peptides were found. Three of them (VMAPRTLIL, VMAPRTLLL, VMAPRTLVL) were found in 88.3% of UL40 and 100% of HLA Class I of healthy individuals. In contrast, 15 of them (10.7%) were not found in HLA Class I. The VMAPRTLFL peptide was found in 1% of UL40 and all HLA-G alleles. Significant differences in peptide (VMAPRTLIL, VMAPRTLLL, VMAPRTLVL, other UL4015-23 peptides, other HLA Class I peptides) distribution between UL4015-23 from congenital CMV and HLA-A, -B, -C and -G from healthy individuals were found. CONCLUSIONS: Our findings suggest that a mismatch between UL4015-23 peptides and HLA Class I peptides between children and mothers might play a role in congenital CMV disease, and it may account for differences in outcome, morbidity and sequelae.

Switching between reference adalimumab and biosimilars in chronic immune-mediated inflammatory diseases: A systematic literature review.

AIMS: Adalimumab is a biological therapy used to treat different chronic inflammatory diseases. At present, there is an increasing number of adalimumab biosimilars. To assume the acceptability of interchangeability between reference adalimumab and biosimilars, there should be evidence about efficacy and safety of this switching. Regulation of this practice falls under the authority of individual European Union Member States. The aim of this study is to systematically review the evidence on the efficacy, safety and immunogenicity of switching between reference adalimumab and biosimilars in different chronic immune-mediated inflammatory diseases. METHODS: Studies presenting data about switching between reference adalimumab and biosimilars were identified by sensitive search strategies in Medline and EMBASE from 1 January 2004 to 30 June 2021. RESULTS: A total of 471 references were obtained and 21 finally included in the analysis (total number of patients switching: 2802). Eight different adalimumab biosimilars were tested after receiving reference adalimumab. Eight articles included rheumatoid arthritis (RA), one miscellaneous rheumatic disease, six psoriasis (PSO) and six inflammatory bowel disease (IBD) patients. Overall, the efficacy results in the switching groups were comparable to those obtained in the arms of continuous biosimilar and continuous reference adalimumab. There were no significant differences in treatment emergent adverse events, anti-drug or neutralising antibodies among the three groups. CONCLUSIONS: Switching between reference adalimumab and biosimilars has no impact on efficacy, safety and immunogenicity in patients with RA, PSO and IBD. This finding was consistent for the different adalimumab biosimilars analysed. These conclusions could probably be extended to other rheumatic diseases such as psoriatic arthritis and ankylosing spondylitis.

Endothelial sprouting, proliferation, or senescence: tipping the balance from physiology to pathology.

Therapeutic modulation of vascular cell proliferation and migration is essential for the effective inhibition of angiogenesis in cancer or its induction in cardiovascular disease. The general view is that an increase in vascular growth factor levels or mitogenic stimulation is beneficial for angiogenesis, since it leads to an increase in both endothelial proliferation and sprouting. However, several recent studies showed that an increase in mitogenic stimuli can also lead to the arrest of angiogenesis. This is due to the existence of intrinsic signaling feedback loops and cell cycle checkpoints that work in synchrony to maintain a balance between endothelial proliferation and sprouting. This balance is tightly and effectively regulated during tissue growth and is often deregulated or impaired in disease. Most therapeutic strategies used so far to promote vascular growth simply increase mitogenic stimuli, without taking into account its deleterious effects on this balance and on vascular cells. Here, we review the main findings on the mechanisms controlling physiological vascular sprouting, proliferation, and senescence and how those mechanisms are often deregulated in acquired or congenital cardiovascular disease leading to a diverse range of pathologies. We also discuss alternative approaches to increase the effectiveness of pro-angiogenic therapies in cardiovascular regenerative medicine.

sp2-Iminosugars targeting human lysosomal ß-hexosaminidase as pharmacological chaperone candidates for late-onset Tay-Sachs disease.

The late-onset form of Tay-Sachs disease displays when the activity levels of human ß-hexosaminidase A (HexA) fall below 10% of normal, due to mutations that destabilise the native folded form of the enzyme and impair its trafficking to the lysosome. Competitive inhibitors of HexA can rescue disease-causative mutant HexA, bearing potential as pharmacological chaperones, but often also inhibit the enzyme O-glucosaminidase (GlcNAcase; OGA), a serious drawback for translation into the clinic. We have designed sp2-iminosugar glycomimetics related to GalNAc that feature a neutral piperidine-derived thiourea or a basic piperidine-thiazolidine bicyclic core and behave as selective nanomolar competitive inhibitors of human Hex A at pH 7 with a ten-fold lower inhibitory potency at pH 5, a good indication for pharmacological chaperoning. They increased the levels of lysosomal HexA activity in Tay-Sachs patient fibroblasts having the G269S mutation, the highest prevalent in late-onset Tay-Sachs disease.

Analysis of the implementation of an innovative IT solution to improve waiting times, communication with primary care and efficiency in Rheumatology.

OBJECTIVE: To describe in detail an innovative program based on telemedicine for semi-automated prioritization of referrals from Primary Care (PC) to Rheumatology, for reproducibility purposes, and to present the results of the implementation study. METHODS: The context and situation were carefully analyzed, paying attention to all processes in place, referral numbers, waiting times, and number of complementary tests prior to discharge from Rheumatology. The composition of the team, aims, users, scope, and implementation phases were defined. Eight process indicators were established and measured before and 32 months after the program implementation. RESULTS: The program, which includes IT circuits, algorithms based on response to specific guideline-based checklists, e-consultation, and appointments based on priority, was fully implemented in our health area after a pilot study in two PC centers. After implementation, 6185 rheumatology referrals showed an e-consultation response delay of 8.95 days, and to first face-to-face visit (after e-consultation) of 12.6 (previous delay before program implementation was 83.1 days). Resolution by e-consultation reached 20% (1195 patients did not need seeing the rheumatologist to have the problem solved), and 1369 patients (32%) were discharged after the first visit. The overall resolution rate was 44.0% (2564 discharges/5830 e-consultations). From a random sample of 100 visits, only 10% of patients needed additional complementary tests to make a diagnosis and decision by Rheumatology (20.9% decrease from previous period). CONCLUSION: A careful analysis of the situation and processes, with implementation of simple IT circuits, allows for the improvement of the efficiency and resolution of problems in Rheumatology.