Chronic nephrotoxicity in psoriatic patients treated with low-dose cyclosporine

Chronic nephrotoxicity is a major complication in high-dose cyclosporine treatment. We examined the glomerular filtration rate, renal plasma flow, and kidney biopsies of 15 psoriatic patients treated with low-dose cyclosporine (< or = 5 mg/kg/d) for 30 months (25 to 35 months) 1 month after drug withdrawal. The mean (95% confidence interval) age of the patients in the study was 44 years (38 to 50 years). Their serum creatinine levels pretreatment and at the time of the study were 0.94 mg/dL (0.85 to 1.0 mg/dL) and 1.2 mg/dL (1.1 to 1.3 mg/dL). Seven patients had a decreased glomerular filtration rate and four of them also had a reduced renal plasma flow, below the 2.5 percentile of normal. Four patients had moderate tubulointerstitial scarring and arteriolopathy, while the remaining patients had mild structural abnormalities. The severity of acute nephrotoxicity during treatment and chronic structural injury were highly correlated (r = 0.81; P < 0.0003). Recurrent episodes of severe acute nephrotoxicity (defined as reversible increase of serum creatinine > 90% of baseline value) was a marker for moderate chronic nephrotoxicity. No correlation was found between chronic structural injury and patient age, sex, pretreatment creatinine level, blood pressure (pretreatment or during treatment), cyclosporine dose and treatment duration, and cyclosporine blood levels. In seven patients continued on cyclosporine for another 12 months (10 to 14 months), repeat studies showed no interval changes. Despite 40 months (30 to 51 months) of treatment, all but one of these seven patients (with previous hypertension and atherosclerotic vascular disease) had mild functional and structural abnormalities. None had any severe acute nephrotoxicity at any time.(ABSTRACT TRUNCATED AT 250 WORDS)

Aplastic osteodystrophy without aluminum: the role of "suppressed" parathyroid function

We evaluated 259 dialysis patients using serum parathyroid hormone (PTH, IRMA; normal range 1 to 5.5 pM or 10 to 55 pg/ml), the deferoxamine infusion test and iliac crest bone biopsy to determine the various forms of renal osteodystrophy and their risk factors. Although half of the biopsied patients had low turnover osteodystrophy, evidence of aluminum toxicity was present in only 1/3 of them. Additional risk factors for this bone lesion included treatment with peritoneal dialysis, ingestion of calcium carbonate, diabetes mellitus and advanced age. The PTH levels in patients with the aplastic lesion were significantly lower than in patients with normal or high bone turnover lesions [7.7 +/- 6.1 vs. 36.9 +/- 3.2 pM (77 +/- 61 vs. 369 +/- 32 pg/ml), P < 0.0001]. Aside from hypercalcemia, these patients were relatively asymptomatic. In a second study, 10 patients on peritoneal dialysis with the aplastic lesion had their dialysate calcium lowered from 1.62 to 1.0 mM. This resulted in a significant increase in PTH levels, from [3.7 +/- 0.8 to 10.6 +/- 1.9 pM (37 +/- 8 to 106 +/- 19 pg/ml), P < 0.001] which persisted over the nine-month observation period. In conclusion, the aplastic lesion is the most common form of renal osteodystrophy, with aluminum intoxication implicated in only 1/3 of the cases. In the remainder, factors identified include therapy with peritoneal dialysis using supraphysiological dialysate calcium, oral CaCO3 intake and diabetes mellitus.(ABSTRACT TRUNCATED AT 250 WORDS)

Extrarenal effect of cyclosporine A on potassium homeostasis in renal transplant recipients

Cyclosporine A (CyA) is known to cause hyperkalemia by impairing renal potassium excretion. However, the observation of transient and severe hyperkalemia occurring within 3 to 5 hours of CyA ingestion in several organ transplant patients led us to postulate that it might also cause a potassium efflux from the intracellular to the extracellular fluid space. We tested this hypothesis by studying 22 nondiabetic, renal transplant patients with stable renal function (serum creatine < 2.25 mg/dL) who were treated with CyA (CyA group; n = 14) or imuran and prednisone (STD group; n = 8). Eight CyA and four STD patients also were treated with a beta-blocker (BB). While at rest, fasting plasma potassium levels were sampled hourly in all patients from 8:00 am to 1:00 pm. All medications (including CyA and BBs) were given after the 8:00 am blood sampling. Venous pH, osmolality, insulin, aldosterone, epinephrine, norepinephrine, and CyA levels also were determined at 8:00 am, 11:00 am, and 1:00 pm. Urine was collected from 11:00 pm to 8:00 am prior to the study (period I) and from 8:00 am to 1:00 pm during the study (period II) for measurement of potassium excretion (standardized to a 5-hour period). A significant increase in serial plasma potassium levels was noted in the CyA + BB group only (P = 0.0006 by repeated measures analysis of variance).(ABSTRACT TRUNCATED AT 250 WORDS)

A Molecular-Based Magnet with a Fully Interlocked Three-Dimensional Structure

A compound has been synthesized with the formula (rad)(2)Mn(2)[Cu(opba)](3)(DMSO)(2).2H(2)O, where rad(+) is 2-(4-N-methylpyridinium)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, opba is orthophenylenebis(oxamato), and DMSO is dimethyl sulfoxide. It consists of two nearly perpendicular graphite-like networks with edge-sharing Mn(II)(6)Cu(II)(6) hexagons. The two networks are fully interlocked with the same topological relationship as that between adjacent rings of a necklace. The compound has three kinds of spin carriers: Mn(II) and Cu(II) ions, antiferromagnetically coupled through oxamato bridges, and rad(+) radical cations, bridging the Cu(II) ions through the nitronyl nitroxide groups and forming Cu-rad chains. The temperature dependence of the magnetization reveals that below 22.5 K, the compound behaves as a magnet.

Renal osteodystrophy in diabetic patients

To assess the effects of diabetes mellitus on renal osteodystrophy, we examined the database of 256 patients (45% on hemodialysis and 55% on peritoneal dialysis) who were prospectively studied in three Toronto dialysis centers between October of 1987 and 1989. All patients had serial documentation of their clinical, laboratory and risk parameters of bone disease, and completed a series of investigations that included the deferoxamine test, measurement of intact 1-84 PTH levels, and an iliac crest bone biopsy. Twenty-five percent of these patients were diabetic. When compared to non-diabetic patients, they were on dialysis for a shorter duration (2.4 +/- 0.3 vs. 4.7 +/- 0.3 years; P < 0.0002), used calcium carbonate as the only phosphate binder more frequently (40 vs. 25%; P < 0.007), and had lower parathyroid hormone levels (12 +/- 1.4 vs. 24 +/- 2.3 pmol/liter; P < 0.002). High-turnover bone disorders (that is, osteitis fibrosa and mixed disorder) were distinctly uncommon (8 vs. 33%; P < 0.01 by Fisher's exact test), while the mild (19 vs. 9%; P = NS) and the aplastic disorders (with mean stainable bone surface aluminum of 6.5 +/- 0.7%) (46 vs. 31%; P = NS) tended to be more common in diabetic patients. The prevalence of aluminum bone disease was the same in both groups (27%). Diabetic patients ingested a smaller cumulative dose of aluminum gels (3.7 +/- 0.6 vs. 9.3 +/- 1.1 kg; P < 0.005), yet had a higher rate of aluminium accumulation on bone surfaces than non-diabetic patients (1.5 +/- 0.19 vs. 0.96 +/- 0.10% per month on dialysis; P < 0.015).(ABSTRACT TRUNCATED AT 250 WORDS)

The spectrum of bone disease in end-stage renal failure--an evolving disorder

We have assessed the bone histology in 259 chronic dialysis patients, all of whom were in the same dialysis program. All patients had bone biopsies with quantitative histomorphometry, intact parathyroid hormone (PTH) measurements, basal and deferoxamine stimulated serum aluminum levels. Results demonstrate the increased incidence of the recently described aplastic bone lesion, particularly in patients treated with peritoneal dialysis (PD). Aluminum-related bone disease is much less common than previously described, perhaps in relation to the declining use of aluminum as a phosphate binder. A different pattern of bone lesions is seen in PD as compared with hemodialysis (HD), with low turnover disorders comprising 66% of the lesions seen in PD and high turnover lesions accounting for 62% of the bone histologic findings in HD. The difference in these patterns may relate to alterations in PTH levels, as mean PTH levels in HD patients were 2-1/2 times the levels found in PD patients (P < 0.0005), while older age, higher prevalence of diabetes and a shorter duration of dialysis may also have contributed to the findings in the PD patients. We suggest that PD, perhaps by maintaining calcium at higher levels, may more effectively suppress the parathyroid gland.

Cyclosporine nephrotoxicity in lung transplant recipients

End-stage lung disease has been treated successfully by lung transplantation (LTXP) at our institution since 1983. We report on the renal function of 30 LTXP recipients who were followed for at least 6 months (mean, 39 months; range, 6-60 months). All patients received quadruple immunosuppressive therapy including cyclosporine A, with a trough serum level (RIA) between 150 and 250 ng/ml for the first 6 months between 125 and 150 mg/ml after 6 months. The mean serum creatinine (SeCr) increased from a baseline value of 75 +/- 3.5 to 182 +/- 13.9 microM at the end of the follow-up. The greatest change in SeCr occurred within the first 6 months post LTXP. Fifteen of 30 patients who were initially normotensive required at least one antihypertensive medication post LTXP. By the end of the follow-up, 9 patients had SeCr > 200 microM. Two patients in this institution have progressed to end-stage renal disease requiring dialytic therapy. CsA nephrotoxicity has emerged as a major source of morbidity in the lung transplant population. Nephrotoxicity occurs early, and there does not appear to be any trend toward reversibility despite a lowering of the dose. Renal parenchymal injury may be progressive, despite an apparent plateau of the SeCr in some patients.

Predicting chronic renal insufficiency in idiopathic membranous glomerulonephritis

We developed an approach in quantifying the risk of developing chronic renal insufficiency (CRI) based on a cohort of 184 patients with idiopathic membranous glomerulonephritis (IMGN), prospectively followed by the Toronto Glomerulonephritis Registry between 1974 and 1988. After a mean follow-up period of 5.8 years, 26% of patients developed CRI (defined as persistent reduction of creatinine clearance (CCr) less than or equal to 60 ml/min/1.73 m2 for greater than or equal to 12 months). We found that when compared to the baseline probability of the unselected patients, the severity of proteinuria at kidney biopsy added only marginally to the prediction of CRI. We introduced a special test condition: persistent proteinuria (PP) (that is, duration of proteinuria, g/day, above different cut-off levels). We examined the positive predictive value (PPV) and sensitivity (SEN) of 15 arbitrarily chosen levels of PP (that is, proteinuria greater than or equal to 4, 6 or 8 g/day persisting for greater than or equal to 6, 9, 12, 18 or 24 months) to select levels with optimal predictive characteristics. We found that PP greater than or equal to 8 g/day for greater than or equal to six months was a simple and useful predictor of CRI with a PPV and SEN of 66%. To further improve our prediction, we tested the following parameters: age, sex, initial SCr and CCr, proteinuria, serum albumin, hypertension, rate of change of CCr over time, and therapy (steroids +/- immunosuppressive drugs) in a multivariate analysis. Proteinuria, initial CCr, and rate of change of CCr were most important in predicting CRI.(ABSTRACT TRUNCATED AT 250 WORDS)

Non-invasive prediction of aluminum bone disease in hemo- and peritoneal dialysis patients

Between October 1987 and October of 1989, we conducted a prospective study to evaluate non-invasive test strategies for predicting aluminum bone disease (ABD) in a group of largely unselected dialysis patients based on their deferoxamine (DFO) test alone, or the combined results of their DFO test and intact 1-84 parathyroid hormone (PTH) levels. These test parameters were evaluated against the pathological diagnosis of ABD based on bone biopsy ("gold standard"). A total of 445 patients in three dialysis centers in Toronto were serially followed for their clinical, laboratory and risk parameters for renal osteodystrophy during the study, and 259 (142 PD and 117 HD) patients underwent a series of investigations which included the DFO test, measurement of intact 1-84 PTH levels, and an iliac crest bone biopsy. Serum aluminum ([Al]) level greater than or equal to 3700 nM (or 100 micrograms/liter) had a positive predictive value (PPV) of 75% for ABD in our PD and 88% in our HD patients, but its sensitivity was low (10 and 37%). Delta [Al] (that is, incremental rise of serum [Al] from baseline post-DFO) was useful in predicting ABD in our PD but not HD patients. Test combination based on delta [Al] greater than or equal to 5550 nM (or 150 microgram/liter) and PTH levels less than 20 pM (or 200 pg/ml) yielded the best PPV greater than or equal to 95% for ABD in both PD and HD patients. This test cut-off would remain highly predictive of ABD even if the prevalence of ABD decreases to as low as 5% for the PD patients and 10% for the HD patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[A multiclinic double-blind, comparative clinical trial on misoprostol in the treatment of duodenal ulcer]

A clinical trial of misoprostol, an analog of PGE1 produced by G.D. Searle & Co., on treatment of duodenal ulcer was carried out in five hospitals in Beijing, Shanghai, and Guangzhou. Totally 94 cases were treated with misoprostol 200 micrograms q.i.d. for 4 weeks. A parallel comparison was made, using cimetidine 200 mg q.i.d. A double-blind, double-dummy study was conducted. The result showed that the therapeutic efficacy of misoprostol in duodenal ulcer is similar to that of cimetidine. The ulcer healing rate in four weeks being 60.7% and 67.9% respectively, while the overall effectiveness rate being 77.7% and 80.2%. There was no statistically significant difference between the two medication groups. The side effect of misoprostol is mainly mild diarrhea (6.4%), but it disappears despite the continued use of medication. To our impression, misoprostol represents a new therapeutic approach for treatment of peptic ulcer in addition to acid controlling H2 blockers.

[Separation of 20(S)-ginsenoside-Rg2 and its 20(R) epimer by reversed phase low pressure column (Rp-18) chromatography]

20(S)-Ginsenoside-Rg2 and its 20(R) epimer were successfully separated using reversed-phase low pressure column (Rp-18) chromatography. The method has proved very convenient and rapid.

ABO blood group incompatible kidney transplantation: a case report and review of the literature

A patient with end-stage renal failure, two previously failed kidney transplants and high serum lymphocytotoxic antibody levels was transplanted electively with an ABO-mismatched, HLA-identical kidney from his sibling. Immunosuppression consisted of pretransplant splenectomy and plasma exchange, followed by rabbit antithymocyte serum, azathioprine, prednisone and plasma exchange in the early post-transplant period. He is now 3 years post-transplant with normal renal function on conventional immunosuppressive therapy. This case, and a review of the literature, suggest that ABO blood group incompatibility need not be an absolute barrier to successful kidney transplantation. ABO incompatible kidney transplantation may be a potentially fruitful area for further research as the demand for donor organs continues to outstrip the supply.

Evidence suggesting under-treatment in adults with idiopathic focal segmental glomerulosclerosis. Regional Glomerulonephritis Registry Study

During the past 11 years, the Metro Toronto Glomerulonephritis Registry has prospectively followed all cases of glomerulonephritis starting from the time of biopsy. Focal segmental glomerulosclerosis was diagnosed by strict histologic criteria in 103 patients. Exclusion of patients with follow-up of less than 12 months reduced the number to 93 (55 adults and 38 children). Mean length of follow-up from the time of biopsy was 61 months. Ninety percent of children, but only 33 percent of adults received treatment with steroids, with or without cytotoxic drugs (p less than 0.001). Complete remission, defined as daily proteinuria of less than 250 mg, was not different in adults (39 percent) from that in children (44 percent), with a mean remission duration for all patients of 38 months. Chronic renal insufficiency, defined as a creatinine clearance of less than 0.8 ml/second/1.73 m2 for more than 12 months, was similar in adults (40 percent) and children (34 percent). Five-year renal actuarial survival, defined as the absence of chronic renal insufficiency, was 96 percent for patients with a history of complete remission, and 55 percent for those without (p less than 0.0002). Logistic regression analysis showed treatment to be the only significant factor for complete remission (p less than 0.001). Complete remission, in turn, was important for renal preservation, defined as the absence of chronic renal insufficiency (p less than 0.001). Age did not affect the treatment response or long-term renal outcome in focal segmental glomerulosclerosis. yet, the percent of adults treated was much lower than that of children, despite the fact that the majority of the untreated adults had the same clinical parameters as the treated adults and children. Thus, a judicious course of treatment is as much indicated in adults as in children with this disorder.

Right atrial ball thrombus as a complication of subclavian catheter insertion for hemodialysis access

In two patients right atrial ball thrombi developed following prolonged subclavian cannulation for hemodialysis. One patient died, the other had the ball thrombus removed by open heart surgery. It appears that repeated friction of the catheter tip may have damaged the endothelium of the right atrial wall. This hitherto unrecognised complication might be prevented by ensuring that subclavian hemodialysis catheters are never allowed to reach as far as the right atrium.

Zinc-induced seizures: a new experimental model of epilepsy

Seizures produced by intracerebral injection of zinc sulfate in rabbits are a new chronic model of experimental epilepsy. The main features of this model are: the animals are easily controlled, the electrocorticogram is conveniently recorded, the endpoints are definite, and the rate of seizure is higher than with other methods. The commonly used antiepileptic drugs, such as phenobarbital (30 mg/kg), diphenylhydantoin (30 mg/kg), nitrazepam (3 mg/kg), and sodium valproate (300 mg/kg), have therapeutic effects in treating this experimental epilepsy, when they are given intravenously. But they can not protect the rabbits from death, except phenobarbital.