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Biomedical subjects

M Arias

Publications and source records attributed to M Arias.

At least 55 records · Page 3Linked to original sources

Proteinuria: a new marker of long-term graft and patient survival in kidney transplantation.

BACKGROUND: Proteinuria developing after renal transplantation is associated with increased renal failure. Moreover, proteinuria in the general population has been shown to be associated with morbidity and mortality due to cardiovascular disease, which is the main cause of death in renal transplant patients. The purpose of the present study was to investigate whether persistent proteinuria following renal transplantation was associated with a worse patient and graft survival. METHODS: We analysed kidney recipients included in the Spanish Chronic Allograft Nephropathy Study (n = 3365). Proteinuria at 1 year post-transplantation was analysed as a categorical variable (< 0.5, 0.5-1, > 1 g/day). RESULTS: Post-transplant proteinuria at 1 year was detected in 15.3% of patients. Graft survival in proteinuric patients was significantly lower as compared with patients without proteinuria and the survival was worse with increasing amounts of proteinuria. In the groups with proteinuria, renal graft function at the time of the analysis was worse than in the group without proteinuria. Patient survival was lower in patients with proteinuria although there was no difference between the two groups of proteinuric patients. The main cause of death was vascular disease in all groups of patients but especially in proteinuric patients. The relative risk of graft failure and patient death was higher in proteinuric patients: graft failure [0.5-1 g/day: 2.33 (1.79-3.01, P<0.0001); > 1 g/day: 3.46 (2.73-4.39, P<0.0001)], patient death [0.5-1 g/day: 2.05 (1.39-3.01, P = 0.0002); > 1 g/day: 2.3 (1.55-3.39, P<0.0001)]. CONCLUSIONS: Proteinuria, as in native kidney disease, is an excellent marker of poor long-term allograft prognosis and is an independent risk factor for total and cardiovascular mortality in the renal transplant population.

Adult↗

[Psychogenic disorders: concepts, terminology and classification].

The neurological interest on functional or psychogenic disorders (mental or physical disturbances with no organic basis, generally unleashed by stressful situations) has been receiving increasingly more interest over the last few years. In this article we review concepts, terms and classifications of these disorders, very different over time and among different authors. Psychogenic disorders are divided into: a) dissociation (with memory, consciousness and self-identity impairment), and b) disturbances with somatizations, divided into somatoform (unconscious), factitious (voluntary search for patient's role) and malingering (searching for material gain). Special emphasis is placed on conversion or hysteria, included in somatoform disorders. New findings in functional neuroimaging are analyzed. These new data suggest an important role of unconscious and involuntary inhibition in loss of volition (similar to hypnosis and different from malingering). Normal activity in certain brain areas (motor or sensory cortex) is blocked by other areas related to emotional integration (anterior cingular and orbitofrontal cortex). The neurologist's role is important to achieve an early diagnosis of psychogenic disturbances, particularly conversive ones. This means the use of fewer economic resources and better prognosis for the patient.

Dissociative Disorders↗

[The neuroscientific work of Justo Gonzalo (1910-1986): the center syndrome and reversal metamorphopsia].

The Spanish neuroscientist Justo Gonzalo Rodriguez-Leal (Barcelona 1910, Madrid 1986) carried out different studies on cerebral functions, highlighting those made in patients with encephalic injuries suffered during the Spanish civil war. His book "Investigaciones sobre la nueva dinámica cerebral. La actividad cerebral en función de las condiciones de excitabilidad nerviosa", published in two volumes (the first one in 1945 and the second one five years later), gathers some of his fundamental contributions, among which the so-called central syndrome stands out. A dominant parietal lesion (central) equidistant from the visual, sensorial and auditory projection areas can lead to diverse perceptive dysfunctions, among them inversions in visual, tactile and acoustic perception. As the lesion becomes more peripheral, the resulting defect will be more unisensorial and crossed, while when it approaches the central region, the disorders will be bilateral and polysensorial. Justo Gonzalo explained all these phenomena later by a gradient system.

History, 20th Century↗

[Clinical suspicion of vertebral osteomielitis: back pain in patients with hemodyalisis by catheter related infection].

The overall incidence of vertebral osteomyelitis is increasing due to, the increasing rates of bacteraemia due to intravascular devices. We report a patient with end-stage renal failure under hemodialysis by internal jugular catheters who started with back pain after several episodes of Staphylococcus aureus bacteraemia, and whose magnetic resonance imaging was showed signs suggestive of spondylodiscitis. Other 4 similar cases from our service have been analysed, thereby we can conclude the most effective treatment of vertebral osteomyelitis and/or epidural abscess is premature diagnosis of these pathologies. Magnetic resonance imaging is the most sensitive radiologic technique whom we have. Treatment of vertebral osteomyelitis must be preceded by a correct bacteriological diagnosis. Surgery plays a central role in the successful treatment and should be performed as soon as neurological problems are apparent.

Anti-Bacterial Agents↗

Prevalence of natural ovine fasciolosis shown by demonstrating the presence of serum circulating antigens.

The prevalence of fasciolosis in sheep (Galicia, Northwest Spain) kept under field conditions was determined by using a sandwich-enzyme-linked immunosorbent assay (sELISA). Serum Fasciola hepatica circulating antigens were captured by means of a rabbit polyclonal IgG antibody to F. hepatica excretory/secretory products. Results were compared to those obtained by faecal sedimentation and an indirect ELISA (iELISA) and excretory/secretory antigens. Prevalences were 39.1% by sELISA, 30.4% by faecal sedimentation and 56% by iELISA; 83.3% of the sheep were positive to any one of the three tests. We observed that 59.5% of the sheep examined had active fasciolosis, 29.1% (117) had antigenaemia, 20.4% (82) passed eggs, and 40 (10%) were positive to both probes. We conclude that there is a high prevalence of fasciolosis in sheep from the studied region, and that the combination of sELISA and coprological sedimentation is extremely helpful for demonstrating current fasciolosis, so its application can be strongly recommended for epidemiological surveys.

Animals↗

Serum antibodies to Dicrocoelium dendriticum in sheep from Sardinia (Italy).

An indirect enzyme-linked immunosorbent assay (ELISA) with Dicrocoelium dendriticum excretory/secretory antigens was used to evaluate the presence of serum antibodies against the trematode in 738 sheep randomly chosen in Sardinia (Italy). Coprological sedimentation was used to discover egg-output. Seropositivity was detected in 86.2% tested sheep, whereas faecal prevalence was 6.7%; all that were faecal-positive also were ELISA-positive.

Animals↗

Impact of the delayed graft function in hypersensitized kidney transplant patients.

AIM: The aim was to study the incidence, impact, and association of pretransplantation anti-HLA antibodies and delayed graft function (DGF) on the outcome of cadaver kidney transplants independent of the immunosuppressive therapy. METHODS: Data from 1325 cadaver donor kidneys (February 1975 to December 2002) included the variables of current and peak anti-HLA antibodies, presence of DGF, acute rejection (AR) episodes, patient survival, and graft half-life. RESULTS: DGF (need for dialysis in the first week posttransplantation) ranged between 15% and 40% with a mean of 30% in last 5 years. Eighty-five percent of the candidates on the waiting list for kidney transplants displayed <25% panel reactive antibody (PRA) at transplantation with 4.6% between 26% and 50%, 7.7% between 51% and 75%, and 1.5% >75%. Among the patients who developed DGF, 47% displayed AR compared an incidence of 30% among patients without DGF (P=.0026). The patients displaying >50% PRA (either current or maximum) showed a worse graft survival compared with patients with <50% PRA (log rank, P=.0000). DGF reduced graft survival (P=.04), the difference appearing in the early phase after transplantation. The best outcome was observed in the no DGF-no AR group (half-life, 11.6 years) and the worst results were in the hypersensitized patient groups: peak and current PRA >50% (half-lives of 2.4 and 2.2 years). A multivariate analysis showed that the presence of peak or current PRA >50% is the most important risk factor for graft loss. CONCLUSION: Sensitization is the key factor in graft outcome. Presensitization increases the risk of DGF and DGF increases the incidence of AR and both together produce the worst graft survivals.

Autoantibodies↗

Pulse pressure is an independent risk factor of cardiovascular disease in renal transplant patients.

Elevated pulse pressure in the general population has been shown to be associated with cardiovascular disease, which is the main cause of death in renal transplant patients. We investigated the effects that a wide pulse pressure has on cardiovascular disease after renal transplantation in a cohort of 532 transplant patients with functioning grafts for more than one year. Patients were classified into two groups depending on whether the one-year pulse pressure was less than or greater than 65 mm Hg. We analyzed patient survival, posttransplant cardiovascular disease and principle causes of death. Five- and ten-year patient survival were lower among the group with higher pulse pressures. The main cause of death was vascular disease in both groups. The presence of posttransplant cardiovascular disease was higher among the group with higher pulse pressures (RR=1.73). In addition, the incidence of an elevated pulse pressure was directly associated with recipient age and posttransplant diabetes mellitus. In conclusion, pulse pressure represents an independent risk factor for increased cardiovascular morbidity and mortality in renal transplant patients.

Blood Pressure↗

Comparison between a two-drug regimen with tacrolimus and steroids and a triple one with azathioprine in kidney transplantation: results of a European trial with 3-year follow up.

This study was designed to assess the efficacy and safety of two immunosuppressant regimens in kidney transplantation based on the administration of tacrolimus-one of them with tacrolimus, azathioprine, and corticosteroids (n=239) and the other with tacrolimus, and corticosteroids (n=236). After completing the initial 3-month study, the patients remaining in the study (197 and 195, respectively) were assessed for 3 years. The incidence of acute rejection (AR) episodes treated during this period was 28.8% with dual-drug therapy and 29.7% with triple-drug therapy. Late AR: episodes between 4 and 36 months were scarce (3.3% in dual and 4.2% in triple therapy). Chronic rejection incidence was 7.7% and 8.9%, respectively. The patients who experienced AR episodes during the first 3 months developed chronic rejection more frequently than those who did not suffer AR. Patient survival at 3 years was 95% vs 95.6%, and graft survival was 86.6% vs 86.5% (NS). Doses and blood levels of tacrolimus were similar in the two groups. Adverse effects were similar among both treatment groups. Median SCr was 123.8 micromol/L vs 114.9 micromol/L in patients who did experience AR: 145.9 micromol/L vs 132.6 micromol/L in those with early AR; and 194.5 micromol/L vs 152 micromol/L in those who presented with late AR. Need for de novo posttransplant insulin was 4.2% in the dual-drug group and 3.8% in the triple-drug cohort. These results demonstrate that, after 3 years of follow up, there were similar efficacy data among the dual- and triple-drug regimens. Thus, addition of azathioprine does not contribute any advantage in the middle term.

Acute Disease↗

Early elimination of cyclosporine in kidney transplant recipients receiving sirolimus prevents progression of chronic pathologic allograft lesions.

Cyclosporine elimination in a regimen including sirolimus has been shown to be a safe and effective approach to improve graft function. Nevertheless, it is still unknown whether the functional benefit of CyA withdrawal coincides with a subsequent reduction in histologic lesions of chronic damage or development of chronic allograft nephropathy. This consideration would forecast a reduction in the rate of long-term graft loss. We analyzed 114 graft biopsies from a subgroup of 57 patients that had been included in a randomized study to eliminate CyA at 3 months posttransplant from a regimen including sirolimus either in group A CyA + SRL vs group B of SRL with CyA elimination at 3 months. Every patient had two biopsies, one at transplantation and another at 1 year. The biopsy reading was performed in a blinded manner by a central pathologist using the Banff 1997 and the CADI classifications. A significantly lower rate of progression of tubular and interstitial chronic lesions between basal and 1-year biopsies was observed for group B patients. In addition, the incidence of new cases of chronic allograft nephropathy during the first year was significantly lower in the group in which CyA had been eliminated at 3 months posttransplant. We conclude that early elimination of CyA in the first months posttransplant, when SRL is used as the main immunosuppressant, reduces the appearance or worsening of chronic histologic lesions, probably as a consequence of long-term CyA toxicity prevention.

Biopsy↗

Effect of early graft function on patient survival in renal transplantation.

The influence of early graft function on long-term graft survival has been widely reported but its association with patient survival has received less attention. We investigated the effect of early renal function on patient survival and on cardiovascular disease after renal transplantation among 532 transplant patients who had grafts functioning for >1 year. Patients were classified into two groups, depending on the early creatinine clearance (< or >60 mL/min). We analyzed graft and patient survival, posttransplant cardiovascular disease, and the principal causes of death. Five- and 10-year graft and patient survival were lower among the group with worse early renal function. The main cause of death was vascular disease. Poorer early renal function increased the risk (RR) of patient death by 2.2-fold, and also the presence of posttransplant cardiovascular disease. In conclusion, patients with poor levels of early graft function are at an increased risk of death. These high-risk groups should be targeted for interventional studies to improve patient survival.

Creatinine↗