Effects of pancreas transplantation on distribution and composition of plasma lipoproteins

In type I (insulin-dependent) diabetic patients, peripheral hyperinsulinemia due to subcutaneous insulin treatment is associated with increased high-density lipoprotein (HDL) cholesterol, and also with an altered surface composition of HDL. Pancreas grafts also release insulin into the systemic rather than into the portal venous system, giving rise to pronounced peripheral hyperinsulinemia. We hypothesized that if peripheral hyperinsulinemia is responsible for high HDL cholesterol and/or altered surface composition of HDL in diabetic subjects, similar changes in the lipid profile should be present in pancreas-kidney transplant recipients (PKT-R). Using zonal ultracentrifugation, we isolated HDL2, HDL3, very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and low-density lipoprotein (LDL) from fasting plasma of 14 type I diabetic PKT-R, eight nondiabetic kidney transplant recipients (KT-R), and 14 healthy control subjects and determined the level and composition of the above lipoproteins. HDL2 cholesterol was increased in PKT-R as compared with KT-R and healthy controls (both P < .05), whereas HDL3 cholesterol was unchanged. However, an altered lipoprotein surface composition was evident in PKT-R: HDL2, HDL3, and LDL were enriched in unesterified cholesterol ([UC] PKT-R v KT-R, P=.13, P < .005, and P < .05, respectively; PKT-R v controls, all P < .005); HDL2 was enriched in phospholipids; and LDL was depleted of phospholipid. KT-R, in contrast, showed no changes in lipoprotein surface composition but a substantial triglyceride enrichment of HDL2 as compared with PKT-R and healthy controls (both P < .05). LDL size as determined by gradient gel electrophoresis was increased in PKT-R compared with controls (P < .005). The plasma concentration of cholesteryl ester (CE) transfer protein (CETP), involved also in phospholipid transfer, was increased in both transplant groups compared with healthy controls (both P < .05). Insulin concentrations in fasting plasma were directly related to CETP levels and to the weight-percentage of UC in HDL3, and inversely to the weight-percentage of phospholipids in LDL (all P < .05). We explain the increase in HDL2 cholesterol and LDL size in PKT-R by their high lipoprotein lipase (LPL) activity conferring an excellent capacity to clear chylomicron triglycerides. Effective handling of postprandial triglycerides, high HDL2 cholesterol, and predominance of LDL pattern A, respectively, are established indicators of a low risk of atherosclerosis. However, it is presently unclear what effects the compositional changes on the surface of HDL and LDL may have on cardiovascular risk in clinically stable PKT-R.

Acute renal failure complicating non-fulminant hepatitis A

Hepatitis, A is usually a mild and self-limiting infection of the liver. Whereas the clinical course is usually benign in children, complications such as prolonged cholestasis and fulminant liver failure have been reported in adults. Acute functional renal failure is an uncommon event in the absence of fulminating liver disease. So far, only cases of acute hepatitis A with biopsy-proven interstitial renal disease or tubular necrosis have been reported [Geltner et al. 1992. Kramer et al. 1986]. We present the case of a 35-year-old, previously healthy male with non-fulminant cholestatic viral hepatitis A, who developed progressive oliguric renal failure requiring dialysis therapy. Kidney biopsy ruled out glomerular disease and tubular necrosis. In the absence of bleeding and other causes of fluid depletion this case may be another variant of hepatorenal syndrome whose etiopathogenesis is only poorly understood.

Lipoprotein metabolism in renal replacement therapy: a review

Lipoprotein disorders are considered an important cause for the high cardiovascular morbidity and mortality in patients with end-stage renal disease and following renal transplantation. This article reviews the disease-associated changes of lipids and lipoproteins in these patients and, where known, the underlying causes and mechanisms. Further, we discuss the perturbed lipoprotein system in relation to the cardiovascular risk of patients on renal replacement therapy. Patients treated by hemodialysis are often hypertriglyceridemic with increased very low density lipoprotein (VLDL) levels and a type IV Frederickson pattern of hyperlipidemia. Total and LDL cholesterol concentrations are usually normal or subnormal. Treatment of end-stage renal disease by peritoneal dialysis results in increased total, VLDL and LDL cholesterol concentrations. Both treatment modalities are accompanied by a decrease of high density lipoprotein (HDL) cholesterol and apolipoprotein AI, whereas lipoprotein(a) [Lp(a)] concentrations are significantly elevated in both groups. Following renal transplantation a high incidence of hypercholesterolemia and hypertrigylceridemia is observed, which is attributed, at least in part, to the immunosuppressive therapy. Most patients normalize HDL cholesterol values and Lp(a) decreases to pre-disease plasma concentrations. Several studies have described elevated levels of cholesterol, triglycerides and Lp(a) in patients with cardiovascular complications during different phases of renal replacement therapy, which indicates a predictive (causative) role of these parameters for atherosclerotic diseases.

Synchronization of neuronal responses in the optic tectum of awake pigeons

Multiunit activity was recorded in the optic tectum of awake pigeons with two electrodes at sites varying in depth and separated by 0.3 to 3.0 mm. Autocorrelation and cross-correlation functions were computed from the recorded spike trains to determine temporal relationships in the neuronal firing patterns. Cross-correlation analysis revealed that spatially separate groups of cells in the tectum show synchronous responses to a visual stimulus. Strong synchronization occurred in both superficial and deep layers of the tectum, in general with zero-phase shift. The response synchronization in the avian optic tectum resembles that observed in the mammalian cortex, suggesting that it may subserve common functions in visual processing.

Role of reticular activation in the modulation of intracortical synchronization

During aroused states of the brain, electroencephalographic activity is characterized by fast, irregular fluctuations of low amplitude, which are thought to reflect desynchronization of neuronal activity. This phenomenon seems at odds with the proposal that synchronization of cortical responses may play an important role in the processing of sensory signals. Here, activation of the mesencephalic reticular formation (MRF), an effective way to "desynchronize the electroencephalogram," was shown to facilitate oscillatory activity in the gamma frequency range and to enhance the stimulus-specific synchronization of neuronal spike responses in the visual cortex of cats.

Integrator or coincidence detector? The role of the cortical neuron revisited

Neurons can operate in two distinct ways, depending on the duration of the interval over which they effectively summate incoming synaptic potentials. If this interval is of the order of the mean interspike interval or longer, neurons act effectively as temporal integrators and transmit temporal patterns with only low reliability. If, by contrast, the integration interval is short compared to the interspike interval, neurons act essentially as coincidence detectors, relay preferentially synchronized input, and the temporal structure of their output is a direct function of the input pattern. Recently, interest in this distinction has been revived because experimental and theoretical results suggest that synchronous firing of neurons might play an important role for information processing in the cortex. Here, we argue that coincidence detection, rather than temporal integration, might be a prevalent operation mode of cortical neurons. We base our arguments on established biophysical properties of cortical neurons and on particular features of cortical dynamics.

On the cerebro-protective effects of caroverine, a calcium-channel blocker and antiglutamatergic drug: double-blind, placebo-controlled, EEG mapping and psychometric studies under hypoxia

1. In a double-blind, placebo-controlled study, the acute antihypoxidotic properties of the calcium-channel blocking and antiglutamatergic caroverine were investigated utilizing blood gas analysis, EEG mapping and psychometry under a transient, reversible, hypoxic hypoxidosis. 2. The latter was induced by a fixed gas combination of 9.8% oxygen (O2) and 90.2% nitrogen (N2) (found in 6000 m altitude), which was inhaled for 23 min under normobaric conditions by 16 healthy, young volunteers. They received randomized after an adaptation session, single oral doses of placebo, 40, 80 and 120 mg caroverine. Evaluation of blood gases, EEG mapping and psychometry were carried out 0, 2, 4, 6 and 8 h post-drug, during hypoxia. 3. Blood gas analysis demonstrated a drop in PO2 from 95 to 33 and 30 mmHg, in PCO2 from 38 to 30 and 30 mmHg in the 14th and 23rd minute of inhalation, respectively, while pH increased from 7.41 to 7.50 and 7.51. Base excess and standard bicarbonate remained stable. 4. EEG mapping under hypoxia exhibited a marked increase of delta/theta, decrease of alpha and an increase of superimposed beta activity, which reflects deterioration of vigilance. 5. Caroverine attenuated this hypoxia-induced vigilance decrement in a dose- and time-dependent manner 6-8 h after 80 mg and 2-8 h after 120 mg. 6. Hypoxic hypoxidosis induced a deterioration of memory and attention variability, which was mitigated by 80 and 120 mg caroverine. However, there was an augmentation of the hypoxia-induced decrement in psychomotor performance after 120 mg. 7. The drug was well tolerated, and there were no significant differences compared with placebo with regard to pulse and blood pressure.

Complement C4 phenotypes in patients with end-stage renal disease

The phenotypes of complement C4 were determined by agarose gel electrophoresis in 130 patients with end-stage renal failure of various causes and compared with those of 140 healthy controls. C4 allotype frequencies did not differ between patients and controls. Null alleles of both isotypes C4A and C4B were increased, but also without reaching significance. In type 1 diabetics an increased frequency of C4AQ0 (25 vs. 11.8%, p < 0.05) was found. Patients with two null alleles were far more frequent in the group with insulin-dependent diabetes mellitus (25 vs. 3.6%, p < 0.01). We confirmed the presence of a previously described uremic variant of C4B1. Additional uremic variants of C4 were detected in uremic patients homozygous for C4A3, B2 and B3. The relative electrophoretic migration values of the uremic variants of C4A3, B1, B2 and B3 were 132.1 +/- 2.9, 35.8 +/- 1.5, 70.4 and 73.9. These variants appear early in the course of chronic renal failure and disappear after successful renal transplantation. Uremic variants are the only acquired C4 phenotypes known so far. How uremia causes these variants remains unclear, but probably involves carbamylation of the C4 molecule.

Amantadine versus biperiden: a double-blind study of treatment efficacy in neuroleptic extrapyramidal movement disorders

Anticholinergic treatment of neuroleptic extrapyramidal movement disorders (EPS) has been associated with induction of tardive dyskinesia. Also an increasing abuse of anticholinergics by schizophrenic patients is noted. Since as early as 1976, positive effects of amantadine (AMA) on neuroleptic EPS have been described, therefore a controlled study of these reports seemed worthwhile. Forty-two schizophrenic patients (of which 7 were dropouts) of three centers entered the study and were treated for EPS in a double-blind design: 18 (11 m, 7 f) with AMA and 17 (8 m, 9 f) with biperiden (BIP). Identical preparations of AMA 100 mg, tid) and BIP (2 mg, tid) were used in treatment of haloperidol-induced EPS (AMA, mean 22.4 mg haloperidol; BIP, mean 19.6 mg haloperidol). Effects of treatment and possible side effects were rated: EPS for the intensity of EPS, BPRS for quantification of psychotic symptoms, FSUCL for rating the side effects and KUSTA to document patients' mood. Ratings were recorded on days 0, 3, 7, 14, 28 and at discontinuation, respectively. All patients were treated with haloperidol and levomepromazine (for tranquilization/sleep induction) and the respective antiparkinsonian agent for 14 days. Patient characteristics did not differ significantly in either groups. In the AMA treatment group, 2 patients dropped out for noncompliance, in the BIP group, 5 (3 no effect, 1 noncompliance, 1 agitation). All results as recorded with the different rating instruments showed a significant (p < 0.01) overall improvement, whereas no significant differences between treatment groups could be determined, notably the treatment effect of both drugs on EPS was similar. Thus, the application of AMA in cases of neuroleptic EPS seems justified and is a useful alternative of anticholinergic drugs. Certain advantageous aspects of AMA treatment of EPS with regard to the glutamate hypothesis of schizophrenia and tardive dyskinesia are discussed.

Transcranial magnetic stimulation: a novel antidepressive strategy?

Transcranial magnetic stimulation (TMS) is a well-established diagnostic probe in neurological practice. The increasing knowledge of biological mechanisms in electroconvulsive therapy presents a clear case for studying the applicability of TMS as a therapeutic tool in psychiatry. Based on the results of our pilot study showing a possible antidepressive effect of TMS, we conducted a controlled clinical trial on patients affected by major depression (DSM-III-R). Group 1 (n = 12) underwent TMS as add-on therapy to standard antidepressive medication, while group 2 (n = 12) was treated only with antidepressive medication. Already after the third add-on TMS session, a statistically significantly greater remission of depressive symptoms occurred in the patients of group 1 (p = 0.003). This statistically significant difference between the groups became even more marked on the last day of the study (p = 0.001, Wilcoxon). The results and further implications of TMS in psychiatric disorders are discussed.

Polymorphism of complement C4 and susceptibility to IDDM and microvascular complications

OBJECTIVE

The aim of this study was to investigate whether or not the inherited polymorphism of complement C4 is associated with genetic susceptibility to microvascular complications in IDDM as previously reported.

RESEARCH DESIGN AND METHODS

We determined C4 phenotypes in 241 patients with IDDM and 140 healthy control subjects by agarose gel electrophoresis and immunoprecipitation. C4 allotype frequencies were compared between patients and healthy control subjects. In addition, we compared allotype frequencies of 83 patients with nephropathy with those of 80 patients without nephropathy and compared those of 50 patients with proliferative retinopathy with those of 68 patients without retinopathy or background retinopathy. Duration of IDDM in control patients was at least 21 years.

RESULTS

Patients and healthy control subjects differed at both the C4A (P < 0.00001) and C4B (P < 0.0005) loci. The C4 null allele C4AQ0 was significantly increased in IDDM patients (26.8 vs. 11.8%, P < 0.005). C4B2 was more frequently observed in patients (14.5 vs. 6.8%, P < 0.05) compared with healthy control subjects. No differences were observed in C4 allotype distribution between patients with and without nephropathy or retinopathy.

CONCLUSIONS

These data confirm previous reports of an association between the C4 null allele C4AQ0 and IDDM. Our results do not support an association of the inherited polymorphism of complement C4 with genetic susceptibility to microvascular complications in patients with IDDM.

CD4 monoclonal antibody VIT4 in human alloimmune response in vitro and in vivo

In the present report the immunosuppressive effects of the murine anti-human CD4 monoclonal antibody (mAb) VIT4 on human alloimmune response in vitro were analyzed. Moreover, the antibody was tested for its activity to prolong allograft survival in seven patients with steroid-refractory allograft rejection. VIT4 inhibited the proliferative response to alloantigens in the mixed lymphocyte reaction (MLR) in a dose-dependent manner. At concentrations of 1 and 10 micrograms/ml VIT4 blocked MLR by 55 +/- 11% and 77 +/- 1%, respectively. Also alloantigen-specific proliferation of in vitro- generated memory T cells was dose-dependently reduced to 23 +/- 1% at a VIT4 concentration of 100 micrograms/ml. Furthermore, at the same dose level VIT4 blocked proliferation of antigen-specific short-term alloreactive CD4+ cell lines and significantly inhibited the in vitro generation of cytotoxic T lymphocytes (CTL). In a pilot study VIT4 (5 mg/d i.v.) was administered to 7 patients with steroid-refractory allograft rejection for 14 days. In 4 of 7 patients graft function transiently improved and graft survival in all patients was prolonged to a mean of 694 days (range 128-2163) from the beginning of the VIT4 treatment. In the light of our in vitro results and the preliminary clinical data, further clinical trials using higher antibody doses are greatly warranted to assess the efficacy of anti-CD4 mAb VIT4 in the treatment of allograft rejection.

Crystal structure of a bZIP/DNA complex at 2.2 A: determinants of DNA specific recognition

The X-ray structure of the GCN4-bZIP protein bound to DNA containing the ATF/CREB recognition sequence has been refined at 2.2 A. The water-mediated interactions between the basic domain and DNA are revealed, and combined with a more accurate description of the direct contacts, further clarify how binding specificity is achieved. Water molecules extend the interactions of both invariant basic domain residues, asparagine 235 and arginine 243, beyond their direct base contacts. The slight bending of the basic domain alpha-helix around the DNA facilitates the linking of arginine 241, 243 and 245 to main-chain carbonyl oxygen atoms via water molecules, apparently stabilizing interactions with the DNA.

The effect of nedocromil sodium on childhood asthma during the viral season

Viral-induced symptomatic respiratory infections (SRI) frequently cause exacerbations of asthma in children. This study investigated the protective effects of 0.5% nedocromil sodium nebulizer solution given three times a day in preventing asthma exacerbations associated with SRI. Ninety-three mild-moderate asthmatic children (6 to 12 yr of age) received either 0.5% nedocromil sodium or placebo for 24 wk during the viral season. The nedocromil sodium group was symptom-free 58% of the days, and the placebo-treated patients were symptom-free 45% of the days (p = 0.027). During Weeks 1-12, significant differences favored nedocromil sodium for asthma summary score (means: nedocromil sodium = 0.61, placebo = 0.92; p = 0.026), and daytime asthma (nedocromil sodium = 0.78, placebo = 1.22; p = 0.03). Significant differences were noted during monthly intervals for cough (Weeks 1-4: nedocromil sodium = 0.61, placebo = 0.92, p = 0.027) and peak expiratory flow rate (PEFR) (nedocromil sodium 262, placebo = 254 L/min, p = 0.041 Weeks 9-12). Patients in the active treatment group reduced their need for rescue inhaled beta 2-agonist by 10%, whereas patients treated with placebo demonstrated a 24% increase. There was a strong correlation between asthma symptoms and SRI symptoms (r = 0.47; p < 0.001). During SRIs, patients in the nedocromil sodium group demonstrated more rapid resolution of asthma symptoms immediately following infection (p = 0.033 summary score, p = 0.039 sleep difficulty). No serious adverse events were noted. Nedocromil sodium did not prevent the infection or exacerbation of asthma symptoms during SRI.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of the timing and the administration of acarbose on postprandial hyperglycaemia

To clarify the optimum timing for ingestion of acarbose, a 100 mg dose of this oral hypoglycaemic agent was administered 30 min before, at the beginning, and 15 min after ingestion of a test meal, and the effects of the drug on blood glucose rises were compared with increases observed after a control meal (no drug). Twenty-four patients with Type 2 diabetes were included in a randomized, open, cross-over study. The smallest increases in blood glucose (p < 0.001) occurred when acarbose was taken at the beginning and 15 min after starting the test meal (3.3 +/- 1.6 mmol l-1 and 3.3 +/- 1.4 mmol l-1). The increase in blood glucose levels when acarbose was taken 30 min before the test meal was significantly higher (4.2 +/- 1.8 mmol l-1) and it was at its maximum following the control meal (5.2 +/- 1.7 mmol l-1). Similar results were observed when the effects of acarbose on insulin and C-peptide levels were measured. It is recommended that patients should be instructed to take acarbose with their first mouthful of food.

Symptom outcome after functional endoscopic sinus surgery in patients with cystic fibrosis: a prospective study

Twenty-nine consecutive patients with cystic fibrosis were offered functional endoscopic sinus surgery. Twenty-six of these patients underwent surgery. A symptom questionnaire was obtained from the patient or parent before surgery. At the end of the study this symptom questionnaire was again administered to the same individual, and 21 completed it. There were 14 male and 7 female patients, with a mean age of 12.3 years and a median age of 8.7 years. Mean follow-up was 34.3 months. Results for the following symptoms were significant: nasal airway obstruction was improved (p < 0.0002), olfactory function was improved (p < 0.0037), purulent nasal discharge was decreased (p < 0.001), and activity level was increased (p < 0.001). Other parameters are also reported in the text. In summary, this study prospectively studies the effects of functional endoscopic sinus surgery on symptoms in patients with cystic fibrosis. The study points out several significant areas of symptom improvement and supports the selective use of functional endoscopic sinus surgery in patients with cystic fibrosis. Indications for surgery are provided.

Influence of various heparin preparations on lipoproteins in hemodialysis patients: a multicentre study

Recent studies have indicated controversial effects of low molecular weight heparin (LMWH) on lipid metabolism in patients on chronic hemodialysis as compared to unfractionated heparin (UFH). We therefore conducted a cross-sectional multicentre study comparing 153 patients treated with LMWH and 153 patients with UFH, matched for sex, age and diabetes mellitus. Both groups have been treated with LMWH or UFH for six months or longer (14.9 vs. 23.4 months). We observed no differences between the UFH and LMWH treatment groups for total cholesterol, LDL cholesterol, triglycerides, apoB, apoA-IV or Lp(a). The only significant differences were seen for HDL cholesterol and the corresponding apolipoprotein apoA-I, which were significantly higher in the UFH group (HDL cholesterol: 0.97 +/- 0.35 mM/l vs. 0.87 +/- 0.37 mM/l, p < 0.05; apoA-I 1.23 +/- 0.27 g/l vs. 1.15 +/- 0.27 g/l, p < 0.05). We conclude that the results of studies investigating the influence of LMWH on lipid metabolism are as heterogeneous as the substances themselves. This challenges the beneficial influence supposedly had by LMWH preparations on lipid metabolism.

Short-term and long-term effects of albuterol aerosol therapy in cystic fibrosis: a preliminary report

The effectiveness of maintenance albuterol aerosol therapy in cystic fibrosis (CF) was assessed by comparing spirometric measurements at the beginning and end of 1 year. Peak expiratory flow rates (PEFR) were measured twice daily to determine bronchodilator responsiveness and spontaneous diurnal variation (SDV), and results were compared with groups of normal and asthmatic children. CF patients not receiving regular albuterol therapy served as a control group. In the treatment group, forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) were significantly increased (12.2% and 18.4%, respectively) over the course of the treatment year, as contrasted with a significant decrease during the preceding year. During the study year the CF control group had a significant decrease in FEV1 and FEF25-75%, and the difference between treatment and control groups was significant for FVC, FEV1, and FEF25-75%. PEFR increased from the first to the last week of the year-long observation period (from 71.8% to 78.7% of predicted values, P < 0.01). Spontaneous diurnal variations were significantly greater in the CF study group than a group of normal children; SDV decreased significantly in the treatment group during the year of study. A bronchodilator response of > 15% was present in 25.8% of CF patient days, but there was considerable interpatient variability. Frequent bronchodilator responders were accurately predicted by their baseline bronchodilator responsiveness, but not by age or personal or family history of asthma or atopy. No difference in long-term pulmonary function improvements were noted between frequent and infrequent responders. The results suggest that maintenance albuterol aerosol treatments reversed the progressive downward course in lung function in the CF treatment group. A double-blind placebo-controlled study is required to confirm these preliminary findings.

Symptom Outcome After Functional Endoscopic Sinus Surgery in Patients with Cystic Fibrosis: A Prospective Study

Twenty-nine consecutive patients with cystic fibrosis were offered functional endoscopic sinus surgery. Twenty-six of these patients underwent surgery. A symptom questionnaire was obtained from the patient or parent before surgery. At the end of the study this symptom questionnaire was again administered to the same individual, and 21 completed it. There were 14 male and 7 female patients, with a mean age of 12.3 years and a median age of 8.7 years. Mean follow-up was 34.3 months. Results for the following symptoms were significant: nasal airway obstruction was improved ( p < 0.0002), olfactory function was improved ( p < 0.0037), purulent nasal discharge was decreased ( p < 0.001), and activity level was increased ( p < 0.001). Other parameters are also reported in the text. In summary, this study prospectively studies the effects of functional endoscopic sinus surgery on symptoms in patients with cystic fibrosis. The study points out several significant areas of symptom improvement and supports the selective use of functional endoscopic sinus surgery in patients with cystic fibrosis. Indications for surgery are provided.

Correlated firing in sensory-motor systems

Traditionally, synchronous firing of neurons has been considered to be an epiphenomenon of neuronal networks, reflecting particular properties of circuitry, but having no functional relevance. In the past few years, an alternative view has been advocated, which suggests that temporal correlations serve a role in information processing by expressing relations among the responses of distributed neurons. This hypothesis has received experimental support from recent in vivo studies performed on the sensory systems of a variety of species. These results support earlier proposals that correlated activity might have an important function in sensory-motor integration and memory.

Multicenter study of lipoprotein(a) and apolipoprotein(a) phenotypes in patients with end-stage renal disease treated by hemodialysis or continuous ambulatory peritoneal dialysis

Numerous studies have investigated lipoprotein(a) (Lp(a)) plasma concentrations in patients with ESRD, a patient group with an enormous risk for atherosclerosis. The reported differences in Lp(a) between controls and patients vary from a decrease of 49% to an increase of more than 1,000%. However, data are not consistent, mostly because of problems with statistical analysis, and only limited data are available for patients treated by continuous ambulatory peritoneal dialysis (CAPD). To estimate the significance of Lp(a) in ESRD and to demonstrate the statistical pitfalls concerning Lp(a) in case-control studies, a large multicenter study including 702 patients treated by either hemodialysis (HD) (N = 534) or CAPD (N = 168) was conducted, and results were compared with results from 256 healthy controls. Both patient groups showed significantly elevated Lp(a) levels in comparison with controls: 23.4 +/- 25.0 mg/dL (P < 0.005; HD) and 34.6 +/- 38.4 mg/dL (P < 0.0001; CAPD) versus 18.4 +/- 22.8 mg/dL (controls). CAPD patients showed significantly higher Lp(a) values than did patients treated by HD (P < 0.001). The difference between the two treatment groups possibly reflects an overproduction of Lp(a) to compensate for protein losses in CAPD patients. Both treatment groups included significantly more patients with Lp(a) values greater than the 75th percentile (25.6 mg/dL) of the control group (33.9 and 41.7% for HD and CAPD, respectively; P < 0.005). The higher Lp(a) values in patients were not explained by differences in isoform frequencies and the increase in Lp(a) was apolipoprotein(a) type specific: only patients with high-molecular-weight apolipoprotein(a) isoforms showed a significant elevation in Lp(a) levels. The increased plasma concentrations of Lp(a) may contribute to the high risk for atherosclerosis in ESRD, especially in patients treated by CAPD. Finally, it is believed that small sample sizes are responsible for the diverging results in Lp(a) literature.