[The immunological barrier in renal transplantation from living donor]

Living donor kidney transplantation is uncommon in our country, mostly due to the high rate of cadaveric donation. However, such a rate has been held back in recent years and it is thought that there will be great problems in organ shortage in the next years, especially for young patients. Thus, living donation seems to be an alternative. Such a practice is particularly useful in hypersensitized patients with positive crossmatch and in ABO incompatibility. In these two cases, the waiting time for kidney transplantation goes on for many years. With the development of desensitizing protocols that employ high-dose intravenous immunoglobulins and/or plasmapheresis, together with the use of more sensitive and objective assays for immunological monitoring, patients that were not candidates for kidney transplantation in the past are now being transplanted. In the present work, immunological factors that participate in living kidney transplantation are revised, with special focus on hypersensitized patients. Available data show that living donation is a feasible alternative for future, once all the ethical problems have been solved.

Comparison of Oestrus ovis metabolic and somatic antigens for the immunodiagnosis of the zoonotic myasis oestrosis by immunoenzymatic probes

Control of zoonosis implies reduction of infected animal hosts, and the first measure consists of a suitable and accurate detection test. An experimental study for determining the most appropriate antigen (metabolic or somatic) to be used in the detection of the oestrosis (Oestrus ovis) zoonotic myasis by means of immunoenzymatic probes was carried out. A flock of 23 uninfected goats was maintained under field conditions to allow their infection in Sassari (Sardinia, Italy). Caprine were bled monthly and serum samples processed by means of an iELISA. After comparing these results to the chronobiology of O. ovis, we proved that the IgG humoral response against the metabolic antigens increased only during the period of real risk of infestation (when adults fly, from May to September), whereas the absorbances against the somatic products were positive from the beginning of the study (in January, prior to infection). We concluded that the excretory/secretory products are most useful and suitable for the immunodiagnosis of oestrosis in goats, because a direct relation between the development of O. ovis and the IgG humoral response is possible, allowing a more accurate diagnostic.

[Microscopic polyangiitis in a patient with rheumatoid arthritis]

Rheumatoid arthritis (RA) is a systemic disorder that primary involves joints, although renal disease has also been associated it is not common that rapidly progressive glomerulonephritis (RPGN) appears. We report the case of a patient with nodular and aggressive RA who had an acut renal failure secondary to ANCA positive RPGN due to a Microscopic polyangiitis who was not responsive to steroids and cyclophosphamide therapy.

[Revascularization of total renal artery occlusion by angioplasty and stent placement]

Revascularization of renal artery stenosis for the treatment of hypertension is an established procedure. In selected clinical scenarios, successful revascularization procedures may preserve or restore renal function. We present a 66-year-old man with secundary hypertension and deteriorating renal function caused by bilateral atherosclerotic renal artery disease (complete obstruction of the left renal artery and subocclusive stenosis of the right) in which blood pressure was successfully controlled and renal function improved and maintained steady after bilateral percutaneus transluminal angioplasty and renal artery stenting.

[Opinion survey on renal donation from living donor]

Spain is the leader country in cadaver kidney transplantation. However the percentage of those transplants coming from living donors represents only a 2% of the total activity. To analyze the cause of this situation the Spanish Society of Nephrology and the National Transplant Organization carried out an opinion pole between patients and health professionals including nephrologists, surgeons/urologists and nurses implicated in kidney transplantation. 60% out the patients consider that the time into the waiting list is to long and 59% don't have any information about living donor kidney transplantation. All the health professionals believe that living donor share better results than get cadaver donors and that the number of the procedure are not enough. Considering that scarcely motivation of professionals and the family of the patients are the main cause. Parents, brothers and sister were considered the best match between donor and recipients and non genetically/emotionally-related donors were accepted by only 2.5%. A 55.7% out of the health professionals considered that the nephrologists are the people that must inform the patients and family about living kidney donation.

[Pharmacogenetics of angiotensin system in non diabetic nephropathy]

BACKGROUND

Genetic variability could contribute to the response to pharmacological treatment in patients with nephropathy. In albuminuric diabetic patients the renoprotective effect of angiotensin I-converting enzyme (ACE) inhibition should be lower among homozygotes for the deletion allele (DD) compared to II-homozygotes.

METHODS

A total of 71 non-diabetic chronic nephropathy patients were treated with losartan (n = 37) or amlodipine (n = 34). Blood pressure and proteinuria were determined before and after the treatment, and changes in the mean values were statistically compared. Patients were genotyped for the ACE-I/D, angiotensin I receptor type 1 (AGTR1)-1166 A/C, and angiotensinogen (AGT)-M235T polymorphims, and the reduction of blood pressure and proteinuria between the different genotypes were compared.

RESULTS

The reduction in systolic or diastolic blood pressure was not found to be different between the ACE-I/D or AGT-M/T genotypes in patients treated with losartan or amlodipine. In patients treated with losartan, we found a significantly higher reduction of diastolic blood pressure in AGTR1-AA patients compared to AC patients (p = 0,0024). We did not find differences in proteinuria-reduction between the different genotypes in patients treated with losartan or amlodipine.

CONCLUSIONS

Our data show that the effects of losartan and amlodipine on the absolute mean reduction of blood pressure and proteinuria in non-diabetic nephropathy patients are similar between the different ACE or AGT genotypes. Although based on a small number of patients, the AGTR1-AA genotype was associated with a significantly higher reduction in diastolic blood pressure among losartan-treated patients. Additional studies are necessary to refute or confirm this association.

Isolation, identification and expression of a Fasciola hepatica cDNA encoding a 2.9-kDa recombinant protein for the diagnosis of ovine fasciolosis

A 400-bp Fasciola hepatica cDNA clone was isolated from an expression library by immunological screening using rat sera taken 2 weeks after experimental infection. The nucleotide sequence of the cDNA revealed the presence of an open reading frame of 78 bp which encoded a 25 amino acid polypeptide with a predicted molecular weight of 2.9 kDa. This polypeptide was expressed in bacteria as a GST-fusion protein and used for the production of specific antigen. The 2.9 kDa recombinant protein (APS) was evaluated against sera from experimentally infected sheep using an indirect ELISA, and the results were compared to those obtained using F. hepatica excretory/secretory products (ESP). The pattern of IgG was very similar both against the recombinant and the native proteins, increasing early following the infection. After treatment with triclabendazole, the IgG response against the APS seroreverted to negative values, whereas it remained elevated against the ESP. We conclude that this recombinant protein could be used in diagnostic assays for the identification of recently infected sheep.

[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.

[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.

[Headache and fainting as initial symptoms of syringomyelia associated to Arnold-Chiari and facial angiomatous nevus]

INTRODUCTION

Syringomyelia and Arnold-Chiari malformation are two dysraphism that often appear together. Clinical manifestations are diverse although some patients remain asymptomatic for years. Syncope, supposedly due to a dysfunction of medulla baroceptors and spinal cord intermediolateral horn, is uncommon, particularly as the initial symptom.

CASE REPORT

34 year old woman, with a facial angiomatous nevus, presented with two episodes of headache followed by syncope; neurological examination was apparently normal. MRI showed mild supratentorial hydrocephalus, Arnold-Chiari malformation and cervical syringomyelia, with no vascular anomalies.

CONCLUSION

This case, which shares some features with Sturge-Weber syndrome and PHACE syndrome, enhances the importance of the search for anomalies in patients with paroxistical symptoms and cutaneous lesions.

[Rapidly progressing dementia as the presenting symptom of Waldenstrom's macroglobulinemia: findings from magnetic resonance imaging of the brain in Bing Neel syndrome]

CASE REPORT

A 68 year old male with no relevant clinical history was admitted to hospital because of symptoms of cognitive impairment (attentional deficit, short term memory disorders and behavioural disorders), accompanied by apraxia of gait and rectal and urinary incontinence. Results of a general clinical exploration were normal. In the MRI study of the brain numerous areas of hypersignal were observed in different arterial territories, which stood out in the T2, FLAIR and, above all, in diffusion weighted sequences. Analytical studies showed hypergammaglobulinemia with monoclonal IgM k and a bone marrow biopsy revealed infiltration by plasmatic cells. Bing Neel syndrome was diagnosed.

CONCLUSIONS

We underline this exceptional form of presentation of Waldenstrom's macroglobulinemia and highlight the findings of diffusion weighted MRI, which suggested multiple infarcts for which a neoplastic vascular obstruction mechanism similar to that involved in malignant angioendotheliomatosis is posited.

[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.

[Experience in the treatment of multiple sclerosis with interferon beta in Galicia]

OBJECTIVE

To analyze the experience in daily clinical practice of interferon-beta (IFN-beta) treatment in relapsing-remitting (RR) and secondary progressive (SP) multiple sclerosis (MS) in Galicia (Spain).

PATIENTS AND METHODS

Patients with RR-MS and SP-MS treated with IFN-beta1a and 1b between 1995 and December/2000, analyzing demographic and clinical data.

RESULTS

313 patients were included, with a mean age of 38.2 years. A total of 296 patients (94.6%) were clinically defined MS and 17 (5.4%) were laboratory supported (Poser criteria); 84.6% of the patients were RR and 15.4% were SP. The mean duration of the disease prior to treatment was 7.06 years. Betaferon was used in 52.4% patients (115 RR-MS and 47 SP-MS), Avonex in 26% and Rebif in 21.6%. Relapse rate was reduced in 68.8% for the RR-MS for Betaferon-treated patients, 73.3% for Avonex treated and 35.7% for Rebif-treated patients. Betaferon reduced relapse rate in 50% for SP-MS. The global EDSS remained stable during IFN-beta treatment. During treatment, 33% of Betaferon, 60.5% of Avonex and 54.5% of Rebif-treated patients remained relapse-free. Treatment was suspended in 12.9% of Betaferon, 6.2% of Avonex, and 3% Rebif-treated patients. The most frequent causes of treatment suspension were increase in disability and in relapse count.

CONCLUSIONS

The present study supports the benefits of IFN-beta treatment in RR MS and SP MS in daily clinical practice, with reduction in relapses count and incapacity, good over-all tolerance and low incidence of serious adverse side-effects.

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.

Highly sensitive PCR assay for routine diagnosis of African swine fever virus in clinical samples

This work provides a novel, highly sensitive, hot start PCR method for rapid and specific detection of African swine fever virus (ASFV) that can be used as a routine diagnostic test for ASFV in surveillance, control, and eradication programs. A confirmatory test of the specificity of this method based on restriction endonuclease analysis was also developed.

[Topiramate therapy in patients with refractory epilepsy]

AIMS

The purpose of this study was to examine the result of administrating topiramate (TPM) to patients with epilepsy that is refractory to treatment with two or more antiepileptic agents.

PATIENTS AND METHODS

A total of 50 patients were evaluated, 90% of which had partial seizures (simple partial, complex partial and partial with secondary generalisation) and the remaining 10% suffered from generalised seizures. The most frequent aetiology was that which corresponded to the symptoms (52% of the cases). 98% of the patients were treated with two or three drugs. TPM was added with a dosage interval between 75 and 550 mg and follow-up visits were carried out throughout a period of nine months.

RESULTS

12 patients remained seizure-free for at least the first three months of the study; in 20 patients the number of seizures decreased by 50% or more; in 14 patients no changes were observed, and in the other four there was an increase in the number of seizures. The best results were obtained in cases of seizures with an idiopathic aetiology, while complex partial seizures offered the worst results. We also analysed the factors that might exert an influence on the different degrees of response.

CONCLUSIONS

TPM was effective in all kinds of seizures. 24% of the patients became seizure free, and the total percentage of respondents rose to 64%. No patients dropped out of the study because of intolerance to the drugs.

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.

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.

Diagnosis of parasitic zoonoses by immunoenzymatic assays--analysis of cross-reactivity among the excretory/secretory antigens of Fasciola hepatica, Toxocara canis, and Ascaris suum

Several parasitic infections such fasciolosis, toxocariosis or ascariosis are important zoonoses. During the infection with Fasciola hepatica, Toxocara canis and Ascaris suum, an important intraorganic phase in their hosts takes place, releasing antigens responsible for a humoral immune response, which enables the diagnosis of that parasitosis. A study to identify the existence of cross-reactivity among the excretory/ secretory antigens of F. hepatica, T. canis and A. suum was developed. One group of Sprague-Dawley rats was infected with 20 metacercariae of F. hepatica and another group remained uninfected as control. By means of an Indirect-ELISA, the rat humoral immune response (IgG and IgM) against the excretory/secretory antigens of F. hepatica was analysed and measured for cross reactivity with T. canis and A. suum. IgM cross-reaction was mainly observed in the first 10 weeks post-infection. IgG cross-reaction was observed throughout the study, and was maximal at the 2-3 weeks and 3-6 weeks post-infection, which corresponds to the intraorganic migratory phase of these parasites. The western-blot showed that the rat IgG recognised three proteins of 190, 160 and 33 kDa in the antigens from F. hepatica, T. canis and A. suum. The existence of cross-reactivity among these antigens seems to demonstrate also the presence of structural similarities, such as tegumental proteins. These results should be consider when immunoassay probes are used in the diagnosis of parasitic infections.

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.

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.