Changes in the gene expression of GABAA receptor subunit mRNAs in the septum of rats subjected to pentylenetetrazol-induced kindling

Chemical kindling was induced in rats by long-term administration of pentylenetetrazol (PTZ) (30 mg/kg three times a week for 9 weeks). The effects of such kindling on the abundance of transcripts encoding subunits of the gamma-aminobutyric acid type A (GABAA) receptor in the brain were measured by RNase protection assay. Kindled rats were examined either 3 or 30 days after discontinuation of PTZ treatment. The amounts of gamma2L and gamma2S subunit mRNAs were significantly increased in the hippocampus and cerebral cortex of kindled rats 3 and 30 days after treatment discontinuation, compared with those observed in control rats, and these effects were prevented by the concomitant administration of the anticonvulsant abecarnil. In contrast, the amounts of alpha1 and beta2 subunit mRNAs in these two brain regions did not differ significantly between kindled and control rats. The abundance of alpha1, beta2, gamma2L and gamma2S subunit mRNAs was decreased in the septum of rats 3 or 30 days after discontinuation of treatment with PTZ either alone or in combination with abecarnil. The amounts of none of the four subunit mRNAs measured differed significantly between the striatum or frontal cortex of kindled rats and control rats 3 days after drug discontinuation. Immunohistochemical analysis with antibodies to choline acetyltransferase revealed a marked decrease in the number of cholinergic neurons in the septum of kindled rats 30 days after discontinuation of PTZ treatment; this effect was not prevented by the administration of abecarnil. These results suggest that long-term treatment with PTZ induces a loss of GABAA receptors in the septum.

Dimensional and hemodynamic differences between native and transplanted kidneys, evaluated by color Doppler ultrasonography

Aim of the study was to asses the differences in size and hemodynamics in the normal kidney and well-functioning renal graft by color Doppler ultrasonography (CDU). Sixty healthy subjects, 75 well-functioning cadaver renal transplant recipients, 15 couples of living donors and related graft recipients were compared by CDU. Renal diameters, volume, renal blood flow (RBF) and renal resistance index (RI) were the variables studied. Cadaveric transplants, living donors and related recipients had a longer kidney (p<0.00001) and greater volume (p<0.001) than normal native kidneys. This was not associated with any significant increase in RBF. RI was lower in healthy subjects and in kidney donors than in transplant recipients (p<0.00001). Transplanted kidneys had a higher arterial RI but apparently normal function.

Promising new agents in the prevention of transplant rejection

Promising immunosuppressive drugs designed to prevent rejection have been developed recently. Two monoclonal antibodies directed against the interleukin-2 (IL-2) receptor, daclizumab and basiliximab, have been shown to significantly reduce the incidence of acute rejection without increasing adverse events. Sirolimus (rapamycin), an agent that inhibits T- and B-response at a later stage than cyclosporin, has been shown to be synergistic with cyclosporin in experimental and clinical studies. Ongoing clinical trials have reported that in renal transplantation high doses of sirolimus are as effective as cyclosporin. SDZ-RAD, a derivative of sirolimus, is also under investigation. FTY-720 another promising drug, prolonged the survival of allografts and synergised with cyclosporin and sirolimus in experimental models. Gusperimus (deoxyspergualin), which inhibits IL-1 synthesis, was useful in reversing early and late acute rejection in clinical trials. Antisense oligonucleotides which interfere with intercellular adhesion molecules which are important in rejection, gave encouraging results in primate renal allografts. The availability of these new drugs will be able to further abate the risk of rejection in organ transplantation. However, caution is warranted with their use in order to avoid the risks of over immunosuppression. Today excellent results can be obtained with the available drugs. Newer immunosuppressive schedules should be designed, not only to reduce the risk of rejection, but also to obtain a better therapeutic index that allows a further improvement of the graft survival while minimising the comorbidity and drug-related toxicity.

Campylobacter jejuni bacteremia and Guillain-Barré syndrome in a renal transplant recipient

In patients who have not undergone transplantation, Guillain-Barré syndrome (GBS) is typically preceded by an acute infection often sustained by Campylobacter jejuni. Thus far, in renal transplant recipients, only eight cases of GBS have been reported. In seven patients GBS was attributed to cytomegalovirus infection and in the eighth patient to cyclosporin A neurotoxicity. We report here the case of a GBS in a renal transplant recipient following C. jejuni bacteremia. The infection quickly disappeared after erythromycin and methronidazole therapy. GBS progressively evolved into a paraparesis within 1 week. After reaching a plateau phase, the clinical status improved and the patient was able to walk unassisted after 3 weeks. At this last check-up, 54 months later, the patient was doing well with a functioning graft and only minimal weakness of the lower limbs.

Proton magnetic resonance spectroscopy in Parkinson's disease and atypical parkinsonian disorders

Proton magnetic resonance spectroscopy (1H-MRS), localized to the lentiform nucleus, was carried out in 12 patients with idiopathic Parkinson's disease (IPD), seven patients with multiple-system atrophy (MSA), seven patients with progressive supranuclear palsy (PSP), and 10 healthy age-matched controls. The study assessed the level of N-acetylaspartate (NAA), creatine-phosphocreatine (Cr), and choline (Cho) in the putamen and globus pallidus of these patients. NAA/Cho and NAA/Cr ratios were significantly reduced in MSA and PSP patients. No significant difference was found between IPD patients and controls. These results suggest an NAA deficit, due to neuronal loss, in the lentiform nucleus of MSA and PSP patients. 1H-MRS is a noninvasive technique that can provide useful information regarding striatal neuronal loss in basal ganglia of patients with atypical parkinsonian disorders and represents a potential tool for diagnosing these disorders.

A randomized study comparing three cyclosporine-based regimens in cadaveric renal transplantation. Italian Multicentre Study Group for Renal Transplantation (SIMTRe)

Whether it is better to treat renal transplant patients with cyclosporine alone, combined with steroids, or combined with steroids and azathioprine is still unclear. After initial therapy with cyclosporine and steroids, 354 cadaver renal transplant recipients were randomly assigned at the post-transplant day 5 to cyclosporine alone (monotherapy), cyclosporine plus steroids (double therapy), or cyclosporine plus steroids plus azathioprine (triple therapy). Monotherapy patients, after a second acute rejection, were switched to either of the two alternative therapies. According to intention-to-treat (ITT) analysis, the 4-year patient survival was 97% in monotherapy, 91% in double therapy, and 96% in triple therapy; the graft survival including death was 84%, 77%, and 88%, respectively; and the pure graft survival was 87%, 85% and 91%, respectively (P = not significant). Acute rejections were diagnosed in 79 patients in monotherapy, 58 in double therapy, and 59 in triple therapy (P < 0.01). Of the patients on monotherapy, 52% were switched to double or triple therapy. In these patients, the 4-year graft survival including death was 68%, and the pure graft survival was 72%, in comparison with 93% and 94%, respectively, for patients who continued on cyclosporine alone. Patients with renal polycystic disease as a cause of renal failure and with low plasma creatinine at the time of randomization (5 days after transplant) had a higher probability of remaining on monotherapy, wherease those with glomerulonephritis or systemic lupus erythematosus (SLE) and with high plasma creatinine levels at randomization had a higher probability of being switched to double or triple therapy. According to ITT analysis, there were fewer ocular (P < 0.0001), osteomuscular (P < 0.002) and cardiovascular complications (P = 0.05) and fewer patients with hypercholesterolemia (P < 0.0028) in the monotherapy group, with no difference between double and triple therapy. Creatinine clearance at 3 years was lower in monotherapy, but no attrition of renal function was seen over the years in any of the groups. Cyclosporine, however used, provided good results in cadaveric renal transplantation. Triple therapy and monotherapy offered a nonsignificantly better patient and graft survival than double therapy. Patients on monotherapy had a higher risk of acute rejection but had fewer adverse events than those on double or triple therapy. Patients maintained on cyclosporine alone had the best graft survival, whereas those who were assigned to monotherapy and had to add steroids because of multiple rejections had the worst outcome. Therefore, it seems reasonable to limit the choice of monotherapy to patients without immune-mediated renal diseases and with good graft function in the early post-transplant period.

Effects of three immunosuppressive regimens on vertebral bone density in renal transplant recipients: a prospective study

The influence of three different immunosuppressive regimens with cyclosporine (CsA) on the development of osteopenia in renal transplant patients was assessed. Fifty-three adults with first kidney transplants participated in a randomized trial to analyze the efficacy of three different immunosuppressive regimens: CsA alone (group 1), CsA plus steroids (group 2), and CsA plus steroids plus azathioprine (group 3). Lumbar spine bone mineral density was assessed by dual energy x-ray absorptiometry every 6 months for 18 months. The values for trabecular mass were expressed as bone mineral density and as a fraction of the standard deviation of the mean of the normal value for patient's sex and decade of age (Z-score). Statistical analysis was performed on Z-score and "Z-score change" (value after 6 months minus the basal value at transplantation). At the 18th month, the Z-score increased significantly in treatment group 1 without steroids (P=0.006) and decreased significantly in steroid-treated groups 2 (P<0.001) and 3 (P<0.001). Comparing the two genders, Z-score decreased less in premenopausal women than in men (P=0.018). "Z-score change" did not correlate with steroid dosage, was high in patients with high basal bone mineral density, and was directly associated with the duration of dialysis (P=0.008). In conclusion, premenopausal transplant recipients showed a lower decrease of lumbar bone mineral density than men. In transplant recipients given CsA with steroids, lumbar bone mineral density decreased significantly, while it increased significantly in patients given CsA alone.

Prognostic factors of long-term allograft survival in 632 CyA-treated recipients of a primary renal transplant

A total of 632 cyclosporin (CyA)-treated primary renal allograft recipients with a functioning graft at 6 months were retrospectively evaluated for risk factors correlated with long-term allograft function. Mean follow-up after the 6th month was 68.4 +/- 40.6 months. One hundred twenty-one of these patients (19%) were lost: 29 died (23/29 with a functioning graft), 77 of the remaining 92 (83%) lost their graft because of chronic allograft dysfunction, 9 due to recurrence of glomerulonephritis, 5 due to renal artery thrombosis, and 1 due to chronic CyA toxicity. At univariate analysis, factors correlated with a better renal (R) and pure renal (PR) allograft survival were: dialysis duration of less than 5 years, fewer than 2 rejections within the 6th post-Tx month, immediate graft function recovery, plasma creatinine below 1.5 mg/dl at the 6th month, age at Tx above 15 years, and receiving a living donor graft. Cox's regression analysis was also performed to obtain relative risks for the same parameters. Long-term dialysis patients had more frequent late recoveries (P = 0.002) and reductions in therapy (P = 0.01) in order to reduce the side effects of steroids. In young patients receiving an initial oral CyA dose of 17 mg/kg per day, steroids were stopped at the 6th month in order to achieve catch-up growth: only one such patient lost his graft. In contrast, 72% of the young patients who lost their grafts received an initial oral CyA dosage of 13 mg/ kg per day. Thus, young patients did worse not because of steroid withdrawal, but because of inadequate initial CyA dosage. These results suggest that although we cannot exclude alloantigen-independent mechanisms as factors that stimulate progression of chronic allograft dysfunction, it would appear that the initial lesions are induced by events mostly mediated by immunological mechanisms.

Cancer incidence in 854 kidney transplant recipients from a single institution: comparison with normal population and with patients under dialytic treatment

In this retrospective historical study, we compared the incidences of malignancies observed among 854 renal transplant recipients (RT) with at least 1 yr of follow-up, with the incidences of neoplasias among patients under regular dialytic treatment (RDT) and a control population from Northern Italy. Cox's proportional hazard model was used in RT recipients in order to evaluate the prognostic factors related to the development of neoplasia. Seventy six out of 854 RT patients (8.9%) developed some malignant neoplasia: 46% of these 76 were cutaneous neoplasias including melanomas, and the remaining 54% non cutaneous cancers: 33% miscellaneous tumors (MT), mostly adenocarcinomas, 17% Kaposi's sarcomas (KS), 4% non-Hodgkin's lymphomas (NHL). Malignancies had a higher incidence (p < 0.01) among RT recipients than among control and RDT patients. However, MT were equally frequent among the three groups. RDT patients on the contrary, had similar incidence of neoplasias when compared to the control population, but showed a lower incidence of squamous cell carcinomas (SCC). The risk ratios (RR) for the most frequent neoplasias among RT recipients vs. control population were: 224.7 for KS, 7.4 for NHL, 6.2 for SCC, 5.7 for basal cell carcinomas (BCC), 4.0 for MT. The risk of developing a de novo neoplasia was of about 13% at 10 yr and of 34% at 20 yr. In RT recipients, Cox's proportional analysis showed that age > 40 at transplantation and male sex were the only risk factors associated with an increased incidence of neoplasias, while no difference was observed between conventional (azathioprine+methylprednisolone: Aza+MP) and CsA therapy or in CsA monotherapy vs. double or triple therapy. However, KS occurrence correlated both with CsA dose (RR 15.2 for monotherapy; 12.5 for double therapy; 2.98 for triple therapy) and with 10 or more i.v. methylprednisolone pulses for treatment of rejection (RR 5.2). We conclude that in our series CsA does not increase the risk for development of neoplasias, when compared to conventional immunosuppression.

Increased detection of antibody to hepatitis C virus in renal transplant patients by third-generation assays

To assess the sensitivity and specificity of third-generation assays for antibody to hepatitis C virus (anti-HCV), sera from 244 renal transplant patients (113 positive for anti-HCV enzyme-linked immunosorbent assay [ELISA]-2) were studied. Hepatitis C virus RNA was detected by a reverse-transcripted nested polymerase chain reaction. Antibody to HCV was detected by ELISA-3 in 108 (96%) ELISA-2-positive samples. Five (4%) ELISA-2-positive sera were negative by both ELISA-3 and polymerase chain reaction. In the anti-HCV-negative group, six (5%) additional cases were ELISA-3-positive; three of these were confirmed by recombinant immunoblot assay-3 (RIBA-3) and polymerase chain reaction. Recombinant immunoblot assay-3 was used to resolve 82 RIBA-2-indeterminate and three RIBA-2-negative sera. Using RIBA-3, 49 (60%) RIBA-2-indeterminate samples were positive, five (6%) ELISA-3-negative samples were negative, and 28 (34%) were remained indeterminate. Recombinant immunoblot assay-2-negative samples were indeterminate with RIBA-3. Hepatitis C virus RNA was detected in all RIBA-3-positive and 58% of the RIBA-3-indeterminate samples. Third-generation assays for anti-HCV are more sensitive and specific than second-generation assays in renal transplant patients.

Randomized study with cyclosporine in kidney transplantation: 10-year follow-up

This study presents the 10-yr follow-up results of a multicenter controlled trial on 108 recipients of cadaveric renal transplantation, randomized to receive cyclosporine (N = 55) or azathioprine (N = 53), both in combination with steroids. The 10-yr patient survival rate was 89% in the cyclosporine group and 83% in the azathioprine group (P = not significant [NS]); the 10-yr graft survival was 56% and 35%, respectively (log-rank test, P = 0.009). The half-life of grafts functioning after 1 yr was 15.4 +/- 3.9 versus 10.6 +/- 3.6, P = NS). The rate of early rejection in the cyclosporine group was significantly lower than that in the azathioprine group (0.30 versus 1.4, P < 0.01). Although the mean creatinine clearance rate was always higher in the azathioprine group, the decline in graft function from the first to the tenth yr was not significantly different between the two groups (-13.0 +/- 16.4 versus -12.3 +/- 19 mL/min, P = NS). In cadaveric renal transplantation, cyclosporine allows better graft survival than azathioprine, not only in the short term but also in the long term, with similar attrition of graft function for up to 10 yr.

Corticosteroids in kidney transplant recipients. Safety issues and timing of discontinuation

Corticosteroids have played a key role in the immunosuppression of organ transplantation. Unfortunately, the extensive use of these agents has resulted in disabling and life-threatening adverse effects in many patients. The advent of concomitant corticosteroid/cyclosporin regimens has allowed a reduction in the dosages of steroids administered, yet steroid-induced morbidity is still a major problem in many cyclosporin-treated renal transplant patients. After favourable initial experiences with cyclosporin monotherapy, several attempts at steroid-free immunosuppression in renal transplant patients have been undertaken, either by not starting steroids after transplantation or by stopping steroids in patients with stable graft function. Most controlled and uncontrolled trials showed that with either strategy short term graft survival was similar with or without steroids, but acute rejection was more frequent in patients not taking steroids. The percentage of patients who could be maintained steroid-free ranged from 28 to 94%, and was higher in patients who stopped steroids later than in those never receiving them. Little information is available about long term follow-up of these patients. Some studies reported late attrition of renal function in patients not taking steroids, while others reported a favourable outcome even in the long term. Steroid-free immunosuppression is feasible in renal transplant patients, but it requires careful monitoring of renal function and cyclosporin dosage. This strategy is particularly indicated in patients at high risk of cardiovascular disease or steroid-related complications, and in children. Nevertheless, several issues need to be better elucidated by further studies, namely the long term outcome of steroid-free immunosuppression, the advantages and disadvantages of steroid avoidance versus steroid withdrawal, and the criteria for selecting patients.

Soluble interleukin-2 receptor (sIL-2R) levels in renal transplantation: comparison between clinical and laboratory analysis

Soluble interleukin-2 receptor levels (sIL-2R) were retrospectively evaluated in 43 consecutive kidney transplant recipients (22 males, 21 females), from day 0 up to 90 days after transplantation. 11 pts were on CsA only, 13 on CsA + MP and 19 on CsA + MP + Aza. All graft-worsening episodes were then retrospectively analyzed, either according to clinical criteria only, or taking into account sIL-2R levels. On clinical grounds, 50 rejections were observed: "a posteriori" 5 turned out to be either infections or non-immunological worsenings of graft function (prevalence of misdiagnosis in the rejection set: 5/50, 10%). Of the 8 infections, 2 were actually treated as rejections (margin of error: 2/8, 25%). CsA toxicity was correctly diagnosed in 2/4 episodes. The analysis based on sIL-2R levels increase confirmed the clinical diagnosis in 52/79 cases (66%). The prevalence of misdiagnosis was: 21.2% in rejection, 2/3 in CsA toxicity, while infections were overestimated in 60% of cases. Isolated sIL-2R level increase was not associated with rejection in 87.5% of cases, while an associated increase of IL-2R and plasma creatinine had a 5% chance of being wrong. SIL-2R levels increased before any rise in plasma creatinine in late rejections (28 +/- 21 days after transplantation), while they increased after the rise of plasma creatinine in early rejections (10 +/- 5 days) (p = 0.014). In the rejection set, sIL-2R had a sensitivity of 83.4%, a specificity of 80%, a positive predictive value of 50.2% and a negative predictive value of 95.2%.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term predictors of survival in essential mixed cryoglobulinemic glomerulonephritis

We report the clinical outcome of 105 essential mixed cryoglobulinemia (EMC) patients with renal involvement collected throughout 25 years in three renal Units of Milan. The median follow-up was 72 months since renal biopsy and 131 months since the clinical onset of EMC. Patient survival was 49% at 10 years after renal biopsy. Forty-two patients died primarily from cardiovascular and liver disease or infection, whereas 15 patients developed chronic renal failure. Two patients had a complete remission of the disease while 15 had a remission only of renal signs. Thirty-one patients are alive with persistent renal and extrarenal manifestations. Anti-HCV antibodies were retrospectively detected in 34 patients and were present in 85% of them. This variable was not included in the statistical evaluation. At multivariate analysis, age older than 50 years, purpura, splenomegaly, cryocrit levels higher than 10%, C3 plasma levels lower than 54 mg/dl, and serum creatinine higher than 1.5 mg/dl were independent risk factors for death or dialysis. In conclusion, several factors may influence the outcome of patients with EMC nephritis. Markers of disease activity and an impaired renal function can herald a bad prognosis. It should be stressed, however, that only a minority of patients eventually develop renal failure, probably because in the most severe cases patients die earlier.

Usefulness of plasma exchange in recurrent nephrotic syndrome following renal transplant

Nephrotic syndrome due to focal segmental glomerulosclerosis (FSGS) frequently recurs even after transplantation and may cause failure of the renal allograft. We report a case in which plasma exchange (PE) was used to treat a 32-year-old patient with biopsy-proven recurrence of FSGS in a second renal transplant after the first allograft had failed. One year after the second renal graft, the patient presented with proteinuria of 5 g/day and a creatinine level of 1.46 mg/dl. A course of 9 PE was performed over a 15-day period. Proteinuria improved rapidly, and 20 days after the last PE, it was already down to 0.8 g/day. This level continued to decrease progressively (0.5 g/day after 3 months) and reached zero after approximately 6 months. Eleven months after PE treatment, the patient had no proteinuria and his plasma creatinine level was normal. In our opinion PE should be instituted early in recurrent nephrotic syndrome after renal transplantation. The optimum frequency of such treatment still has to be established, especially with regard to its use as long-term maintenance therapy.