Attitudes about organ and tissue donation among the general public and blood donors in Hong Kong

CONTEXT

The cadaveric organ and tissue donation rate in Hong Kong is not satisfactory; 1 million blood donors are registered and more than 300,000 are active. However, the current attitudes toward organ and tissue donation in the general public and blood donors of Hong Kong are unknown.

METHODS

Random general public (n = 1018) and blood donors (n = 1227) of Chinese origin, with age ranging from 16 to 60 years, were interviewed using a standard verified questionnaire that examines attitudes and knowledge of organ and tissue donation.

RESULTS

The mean age of the general public and blood donors were 32.6 and 28.9 years, respectively. Of the general public, 44.4% were men and among blood donors, 60% were men. About 56% of both groups thought that organ donation is an obligation of citizens. Blood donors were more aware than the general public about the types of organs that can be donated. When compared with the general public, a significantly higher percentage of blood donors were willing to donate their organs (81% vs 53%), had heard about organ donation cards (98.3% vs 89.5%), and had signed the cards (49.9% vs 22.6%). About 70% of both groups who had signed a card were carrying it. Thirty-nine percent of the general public and 17% of blood donors had not decided whether they would donate. For blood donors, 49.7% were willing to donate their relatives' organs, compared with 41.8% of the general public. Most individuals in both groups would not object to their relatives' decision to donate. About two thirds of individuals in both groups disagreed with the concept of an opt-out law, though only 20% of the general public and 14.4% of blood donors would refuse donation if an opt-out law were in practice.

CONCLUSIONS

This study shows that blood donors have better knowledge of organ donation and are more willing to donate their organs and sign an organ donation card than the general public. However, a substantial proportion of blood donors have not signed a donor card. It would be useful to design promotion programs to facilitate blood donors' participation in organ donation.

Clinical course of peritonitis due to Pseudomonas species complicating peritoneal dialysis: a review of 104 cases

BACKGROUND

Peritonitis due to Pseudomonas species is a serious complication in continuous ambulatory peritoneal dialysis (CAPD) patients. The clinical course of peritonitis due to Pseudomonas complicating CAPD remains unclear.

METHODS

All of the Pseudomonas species episodes of peritonitis in our dialysis unit were studied from 1995 to 1999. During this period, there were 859 episodes of peritonitis recorded, 113 of which were caused by the Pseudomonas species. Nine episodes were excluded because they were mixed growth. The remaining 104 episodes in 68 patients were reviewed.

RESULTS

The underlying renal diagnosis and prevalence of comorbid conditions of the 68 patients were similar to those found in our entire dialysis population. There was a history of antibiotic therapy within 30 days of the onset of peritonitis due to the Pseudomonas species in 69 episodes (66.3%). In 47 episodes (45.2%) there was a concomitant exit site infection. The overall primary response rate was 60.6% and the complete cure rate was 22.1%. The presence of exit site infection was associated with a lower primary response rate (22 in 47 vs. 41 in 57 episodes, P < 0.01) and a lower complete cure rate (5 in 47 vs. 18 in 57 episodes, P < 0.02). The episodes that had received recent antibiotic therapy had a significantly lower complete cure rate than the de novo cases (8 in 69 vs. 15 in 35 episodes, P < 0.001). Episodes receiving third-generation cephalosporin as part of the initial antibiotic regimen had a significantly higher primary response rate than the ones that initially received aminoglycoside (54 in 81 episodes vs. 8 in 22 episodes, P < 0.05), but their complete cure rates were similar. Twenty-four cases failed to respond to antibiotics and the Tenckhoff catheter was removed. The chance of returning to CAPD was higher when the Tenckhoff catheter was removed on day 10 than on day 15 (9 in 14 cases vs. 5 in 10 cases), although the result was not statistically significant. The Tenckhoff catheter was removed and replaced at another site simultaneously in another 14 cases after the effluent cleared up. None of these patients had a relapse of peritonitis within three months.

CONCLUSIONS

Recent antibiotic therapy is the major risk factor for peritonitis due to the Pseudomonas species. Exit site infection and recent antibiotic therapy are associated with poor therapeutic response to antibiotics. When the therapeutic response is suboptimal, early Tenckhoff catheter removal may help preserve the peritoneum for further peritoneal dialysis. Elective Tenckhoff catheter exchange after clearing up the peritoneal dialysis effluent may also reduce the likelihood of relapse. It is desirable to use third-generation cephalosporin in the initial antibiotic regimen for peritonitis treatment in localities with a high incidence of peritonitis due to the Pseudomonas species.

The natural history of immunoglobulin a nephropathy among patients with hematuria and minimal proteinuria

PURPOSE

To determine the natural history of immunoglobulin (Ig) A nephropathy among patients who presented with hematuria and minimal proteinuria, and factors associated with the development of adverse clinical events, such as proteinuria.

SUBJECTS AND METHODS

In Hong Kong, all patients who present with isolated hematuria are referred for renal biopsy after urologic diseases are ruled out. We reviewed the clinical course of 72 consecutive patients with histologically confirmed IgA nephropathy who presented with hematuria and minimal proteinuria (0.4 g/day or less). All patients were normotensive and had normal renal function at presentation. Adverse events were defined as proteinuria greater than 1 g per day, hypertension, or impaired renal function (serum creatinine level 120 micromol/L or estimated creatinine clearance < 70 mL per minute).

RESULTS

The mean (+/- SD) age at presentation was 27 +/- 8 years; 56 (78%) were female. Nine patients (13%) had grade 2 histologic lesions. During a median follow-up of 7 years, 32 patients (44%) developed adverse events: 24 (33%) developed proteinuria of 1 g per day or more, 19 (26%) became hypertensive, and 5 (7%) developed impaired renal function. Another 30 patients (42%) had persistently abnormal urinalysis examinations. Only 10 patients (14%) had complete resolution of hematuria. The median time for progression from proteinuria (> l g/day) to renal impairment was 84 months (range 56 to 132). In a multivariate analysis, age at presentation (relative risk [RR] per 10 years of age = 2.0; 95% confidence interval [CI], 1.2 to 3.4) and histologic grade (grade 2 versus grade 1, RR = 4.5; 95% CI, 1.7 to 12) were independent predictors of developing an adverse event.

CONCLUSIONS

IgA nephropathy that presents with hematuria and minimal proteinuria is usually a progressive disease. Life-long follow-up with regular monitoring of blood pressure and proteinuria is recommended.

Plasminogen activator inhibitor-1 gene polymorphism 4G/4G genotype and lupus nephritis in Chinese patients

BACKGROUND

Abnormal regulation in the coagulation and fibrinolytic system may play an important role in mediating glomerular damage in lupus nephritis. Indeed, glomerular thrombosis occurs frequently in lupus nephritis and predicts the future development of glomerular sclerosis. In the murine model of active lupus nephritis, plasminogen activator inhibitor-1 (PAI-1) gene was overexpressed throughout the kidney, both within the glomeruli and also in tubules and vessels. The level of PAI-1 expression in the tissues appeared to correlate with the progression of lupus nephritis. Recently, a single base pair insertion/deletion 4G/5G polymorphism of the PAI-1 gene has been identified and shown to alter plasma PAI-1 activity. This study was therefore conducted to determine the association of the 4G/5G polymorphism of the PAI-1 gene with the development and severity of lupus nephritis.

METHODS

The PAI-1 gene polymorphism of 118 systemic lupus erythematosus (SLE) patients and 103 healthy controls who were gender and age matched was determined using standard polymerase chain reaction. PAI-1 genotype results were studied in relationship to the development and severity of lupus nephritis.

RESULTS

Allele frequencies of 4G/5G allele were 0.59/0.41 in lupus patients and 0.59/0.41 in controls (P = 1.000). No significant difference was noted in the genotype distribution between SLE patients with and without nephritis. However, lupus nephritis patients with the 4G4G genotype showed significantly heavier proteinuria (5.0 vs. 3.7 g/day; P = 0.023) when compared with patients with 4G5G and 5G5G genotypes. Also, 73.3% patients with 4G4G had an activity index > or =8 versus 37.3% patients with 4G5G and 5G5G (P = 0.003). Extensive necrotizing lesions were seen in 51.7% patients with 4G4G as compared with 23.5% patients with 4G5G and 5G5G (P = 0.014). The association of the 4G4G gene polymorphism with a higher nephritis activity and more severe necrotizing lesions persisted when only class III and class IV nephritis patients were studied. On the other hand, no significant association was noted between the PAI-1 gene polymorphism and the chronicity of the nephritis.

CONCLUSION

These findings suggest that the 4G/5G polymorphism of the PAI-1 gene is associated with the activity but not the chronicity of lupus nephritis. The presence of the 4G4G genotype does not increase the risk of developing SLE or lupus nephritis, but predicts the development of higher nephritis activity and more extensive necrotizing lesions.

Policy implications on assistance for the "caged elderly" in Hong Kong

Social policy for the "caged elderly" in Hong Kong should be formulated in the context of how they lived in the society where they were located. The paper examines (1) whether some of these elderly experienced financially constrained conditions with a weakened social support system; and (2) what policy choices, such as compassionate housing or closer monitoring of such residences, can be undertaken by a formal organization.

Peritoneal transport status correlates with morbidity but not longitudinal change of nutritional status of continuous ambulatory peritoneal dialysis patients: a 2-year prospective study

Cross-sectional studies show that peritoneal transport status is associated with nutritional status and clinical outcome of continuous ambulatory peritoneal dialysis (CAPD) patients. High transporters often are assumed to have progressive malnutrition as a result of fluid overload and nutrient loss in dialysis effluent. There are few prospective data to confirm this assumption, however. We studied 235 unselected CAPD patients to examine this possibility. There were 58 new cases and 177 prevalent cases. A standard peritoneal equilibration test was performed at enrollment. All patients were followed for 2 years. Dialysis adequacy and nutritional assessment, including serum albumin, protein nitrogen appearance, and lean body mass, were performed at 0, 12, and 24 months. Clinical outcome included hospitalization, actuarial patient survival, and technique survival. The mean age was 51.6 +/- 12.4 years. The mean 4-hour dialysate-to-plasma ratio of creatinine was 0.57 +/- 0.12 for all cases (0.60 +/- 0.12 for new cases). Patients were classified into three groups: high/high-average (H/HA) (63 cases), low-average (LA) (105 cases), and low (L) (67 cases) transporters. Baseline demographic data and total Kt/V were similar in all transport groups. There were weak correlations between 4-hour dialysate-to-plasma ratio of creatinine and baseline serum albumin (r = -0.249, P: < 0.001), protein nitrogen appearance (r = -0.190, P: < 0.01), and percentage of lean body mass (r = -0.194, P: < 0.01). The H/HA group was a specific but not a sensitive predictor of poor baseline nutritional status. There was no significant change in any nutritional indices after 2 years in new cases and prevalent cases, regardless of transport status. The differences in nutritional indices between groups remained unchanged during the study period. There was a significant difference in hospitalization rate among peritoneal transport groups (median 12 versus 7 versus 3 days per year for H/HA, LA, and L groups, Kruskal-Wallis test, P: < 0.05). The difference remained similar when new cases and prevalent cases were analyzed separately. The L group had slightly better 2-year patient survival than the H/HA group (90.2% versus 83.3%), but the result was not statistically significant. We conclude that peritoneal transport status is not associated with longitudinal change of nutritional parameters, although transport status is associated with short-term patient morbidity. Further study is needed to identify the mechanisms of poor clinical outcome in high peritoneal transporters.

Comparison of non-breath-hold high resolution gadolinium-enhanced MRA with digital subtraction angiography in the evaluation on allograft renal artery stenosis

AIM

The study objective was to compare the diagnostic accuracy of non-breath-hold high resolution gadolinium-enhanced magnetic resonance angiography (Gd-MRA) with intra-arterial digital subtraction angiography (DSA) in the evaluation of allograft renal artery stenosis (ARAS).

MATERIALS AND METHODS

We studied 17 renal transplant recipients (six men, 11 women, age 34-64 years) with a systolic bruit in the transplant region beyond the early post-operative period. Gadolinium-enhanced magnetic resonance angiography was performed by non-breath-hold high resolution 3D acquisition in the oblique coronal plane using a 256 x 512 matrix.Digital subtraction angiography was performed with AP and oblique views and ARAS was graded as < or =50% or >50% diameter stenosis on the view that displayed the maximal narrowing.

RESULTS

Digital subtraction angiography showed >50% stenosis in seven patients, all of whom were diagnosed correctly on Gd-MRA. Gadolinium-enhanced magnetic resonance angiography diagnosed two patients with >50% stenosis which were not confirmed on DSA. Eight patients had no or < or =50% stenosis on both Gd-MRA and DSA. The sensitivity and specificity of Gd-MRA in revealing >50% stenosis were 100% and 75%, respectively, using DSA as the gold standard.

CONCLUSION

High resolution Gd-MRA employing a non-breath-hold technique is highly sensitive in the diagnosis of ARAS greater than 50%. It is preferred as a non-invasive screening technique to DSA in suspected ARAS.

Reversible renal failure in paroxysmal nocturnal hemoglobinuria

A Chinese patient with paroxysmal nocturnal hemoglobinuria (PNH) developed acute nonoliguric renal failure with intercurrent urinary tract infection and hemolysis. There was no evidence of renal vein thrombosis. Renal biopsy showed features of acute tubular necrosis (ATN) and hemosiderosis. Magnetic resonance imaging (MRI) showed characteristic features of renal hemosiderosis. The patient was stabilized with temporary hemodialysis and intravenous fluid. The renal function fully recovered 3 weeks later. We review the literature and summarize the clinical features of this disease entity. To our knowledge, this case is the first to report such disorder with thorough investigation including concomitant diagnostic MRI imaging and renal biopsy.

N1E-115 mouse neuroblastoma cells express MT1 melatonin receptors and produce neurites in response to melatonin

Melatonin, a pineal hormone that induces sleep, has become a popular over-the-counter drug. The cellular effects of melatonin, however, are only beginning to be studied. We have recently shown that stimulation of the MT1 melatonin receptor induces rapid and dramatic cytoskeletal rearrangements in transformed non-neuronal cells (Witt-Enderby et al., Cell. Motil. Cytoskel. 46 (2000) 28). These cytoskeletal changes result in the formation of structures that closely resemble neurites. In this work, we show that the N1E-115 mouse neuroblastoma cell line rapidly responds to melatonin stimulation and forms neurites within 24 h. We also demonstrate that these cells readily bind 2-[125I]iodomelatonin at levels consistent with what is noted for native tissues (B(max)=3.43+/-1.56 fmol/mg protein; K(d)=240 pM). Western analysis shows that these cells possess and express melatonin receptors of the MT1 subtype. Treatment with pertussis toxin eliminates neurite formation whereas treatment with the MT2 subtype-specific activator, BMNEP, does not induce neurite formation. We have previously shown that increases in MEK 1/2 and ERK 1/2 phosphorylation are correlated with the shape changes in transformed CHO cells. Western analysis of the MEK/ERK signaling pathway in N1E-115 cells shows that this pathway is most likely maximally and constitutively stimulated. This may account for the spontaneous production of neurites noted for this cell line after long culture periods. The results of this work show that melatonin receptor stimulation in a neuronal cell type results in the formation of neurites and that the receptors responsible for melatonin-induced neurite formation in N1E-115 cells are most likely of the MT1 subtype.

Steroid sulfatase activity in the rat ovary, cultured granulosa cells, and a granulosa cell line

Direct production of gonadal steroids from sulfated adrenal androgens may be an important alternative or complementary pathway for ovarian steroidogenesis. The conversion of sulfated adrenal androgens, present in serum at micromolar concentrations in adult women, into unconjugated androgens or estrogens requires steroid sulfatase (STS) activity. STS activity has not been characterized in the rat ovary. Substantial STS activity was present in homogenates of rat ovaries, primary cultures of rat granulosa cells, and a granulosa cell line, as determined by conversion of radiolabeled estrone sulfate (E1S) to unconjugated estrone. The potent inhibitor estrone sulfamate eliminated the STS activity. Using E1S as a substrate with microsomes prepared from a granulosa cell line, the K(m) of STS activity was approximately 72 microM, a value in agreement with previously published data for rat STS. Therefore, ovarian cells possess STS and can remove the sulfate from adrenal androgens such as dehydroepiandrosterone sulfate (DHEA-S). Using DHEA-S as a steroidogenic substrate represents an alternative model for the production of ovarian steroids versus the "two cell, two gonadotropin" model of ovarian estrogen synthesis, whereby thecal cells produce androgens from substrate cholesterol and granulosa cells convert the androgens into estrogens. The relative contribution of STS activity to ovarian steroidogenesis remains unclear but may have important physiological and pathophysiological implications.

Factors predicting outcome of fungal peritonitis in peritoneal dialysis: analysis of a 9-year experience of fungal peritonitis in a single center

Fungal peritonitis causes significant morbidity and mortality for patients undergoing continuous ambulatory peritoneal dialysis (CAPD). We retrospectively reviewed 70 episodes of fungal peritonitis in a single center over the last 9 years in 896 CAPD patients. Seventy percent of the episodes of fungal peritonitis were caused by Candida species, among which 50% were Candida parapsilosis. As a result of fungal peritonitis, 44% of the patients died, whereas further peritoneal dialysis failed in 14%, requiring a change to long-term hemodialysis. Only 37% managed to continue CAPD. The remaining 5% either underwent transplantation or were lost to follow-up. We identified the factors associated with poor outcome, namely mortality and technique failure. The presence of abdominal pain, bowel obstruction, and a catheter remaining in situ were significantly associated with greater mortality. Abdominal pain, antibiotic use within 3 months before fungal peritonitis, and complication by bowel obstruction were associated with greater technique failure. In choosing antifungal agents with catheter removal, oral fluconazole alone appears equally as effective as combined oral fluconazole with 5-flucytosine for peritonitis caused by Candida species. For peritonitis caused by species other than Candida, the choice of antifungal therapy needs to be individualized, based on fungal species and sensitivities.

Longitudinal study of peritoneal membrane function in continuous ambulatory peritoneal dialysis: relationship with peritonitis and fibrosing factors

BACKGROUND

The peritoneal equilibration test (PET) is a useful assessment of peritoneal function in continuous ambulatory peritoneal dialysis (CAPD) patients. However, the natural course of longitudinal change in peritoneal transport is not well defined.

PATIENTS

We studied 105 unselected CAPD patients. Average age at enrollment was 50.7 +/- 11.3 years.

METHODS

A PET was performed at enrollment. Peritoneal transport was expressed as dialysate-to-plasma creatinine ratio at 4 hours (DIP). Fibrosing factors and mesothelial cell markers, including TGFbeta, epidermal growth factor (EGF), platelet-derived growth factor (PDGF), hyaluronan, and cancer antigen 125 (CA125), were measured in overnight peritoneal dialysate effluent (PDE). Patients were followed for two years. Peritonitis episodes were recorded. Severe peritonitis was defined as an episode that required catheter removal or antibiotic therapy for more than 3 weeks. After two years, 75 patients were still alive and on CAPD.

RESULTS

The PET was repeated in 64 patients, of whom 35 were male and 9 had diabetes. The change in D/P over two years was represented as AD/P. No significant change in peritoneal transport was seen after two years (D/P: 0.56 +/- 0.12 vs 0.55 +/- 0.13). A centripetal pattern of change in D/P was observed. The deltaD/P had normal distribution and was inversely correlated with D/P at baseline (r = -0.427, p < 0.005). Both results suggest a regression-to-mean phenomenon. The deltaD/P had no significant correlation with the total number of peritonitis episodes (Spearman r = 0.052, p = 0.74), but after severe peritonitis, affected patients had higher deltaD/P than patients who experienced no severe infection (0.040 +/- 0.136 vs -0.032 +/- 0.120, p < 0.05). For patients with no episodes of severe peritonitis (n = 47), deltaD/P was weakly correlated with baseline TGFbeta level (r = -0.506, p < 0.01). No correlation was seen between the levels of other fibrosing factors and change in peritoneal transport.

CONCLUSIONS

Our findings suggest that the centripetal change of peritoneal transport probably reflects a regression-to-mean phenomenon. Peritoneal transport increases after severe peritonitis. The role of TGFbeta levels in PDE with regard to longitudinal change in peritoneal transport requires further study.

The role of lean body mass as a nutritional index in Chinese peritoneal dialysis patients--comparison of creatinine kinetics method and anthropometric method

OBJECTIVE

To compare, in Chinese continuous ambulatory peritoneal dialysis (CAPD) patients, the creatinine kinetics method (LBM-CK) and the anthropometric method (LBM-AM) for determining lean body mass (LBM).

DESIGN

Single-center cross-sectional study.

PATIENTS AND METHODS

We studied 151 unselected CAPD patients (78 males, 73 females). We calculated LBM-CK and LBM-AM using standard formulas. The results of the two methods were then compared by the Bland and Altman method. Dialysis adequacy and other nutritional indices, including total Kt/V, weekly creatinine clearance (CCr), residual glomerular filtration rate (GFR), protein nitrogen appearance (PNA), subjective global assessment (SGA), and serum albumin, were measured simultaneously.

RESULTS

The mean age of the patients was 55.6 +/- 12.2 years, and the mean duration of dialysis was 33.6 +/- 28.5 months. The mean body mass index (BMI) was 22.7 +/- 3.7. The average LBM-AM was 43.6 +/- 8.0 kg; the average LBM-CK was 33.0 +/- 9.3 kg. The difference between the calculated LBM-AM and LBM-CK was 10.7 kg, with LBM-AM always giving a higher value; the limits of agreement were -5.8 kg and 27.1 kg. The difference between the two measures correlated with residual GFR (Pearson r = 0.629, p < 0.001). After normalizing for desired body weight, LBM-AM was only modestly correlated with serum albumin level. No correlations were found between overall SGA score or normalized protein nitrogen appearance (nPNA) and LBM-AM or LBM-CK.

CONCLUSIONS

In Chinese patients at least, a substantial discrepancy exists between LBM-AM and LBM-CK. The difference is especially marked in patients with significant residual renal function. The optimal method for determining LBM remains obscure in Chinese CAPD patients. Moreover, LBM correlated poorly with other nutritional indices. Multiple parameters should be taken into consideration in an assessment of nutritional status of CAPD patients.

Nephrotic syndrome in strongyloidiasis: remission after eradication with anthelmintic agents

Strongyloides stercoralis infection is known to be important because of its potential for life-threatening disseminated infection in immunosuppressed hosts. Apart from direct invasion into nearly every organ in systemic infection, evidence suggests that immunological reaction also plays a role in the pathogenesis of the disease, including both uncomplicated and disseminated infections. However, Strongyloides-related glomerulonephritis has not been well documented. We present a case of steroid- and cyclophosphamide-resistant nephrotic syndrome complicated by disseminated strongyloidiasis which responded to anthelmintic agents. The remission of nephrotic syndrome after treatment of Strongyloides infection strongly suggests the possibility of Strongyloides-associated glomerulonephritis. Nephrotic patients in endemic areas of Strongyloides infection should have the differential white cell count checked. Strongyloides infection should be ruled out in patients with eosinophilia before immunosuppressants are initiated to prevent the complication of disseminated strongyloidiasis.

Prevalence of sleep disturbances in chinese patients with end-stage renal failure on continuous ambulatory peritoneal dialysis

Patients with end-stage renal failure (ESRF) are reported to have a high prevalence of sleep disorders, such as daytime sleepiness, insomnia, restless legs syndrome (RLS), and obstructive sleep apnea syndrome (OSAS). However, there are few published data from Southeast Asia. A sleep questionnaire was administered to 201 patients (103 men) at the continuous ambulatory peritoneal dialysis (CAPD) outpatient clinic to assess sleep problems. Patients had a mean age of 56.7 +/- 12 (SD) years, with a mean body mass index (BMI) of 23.6 +/- 3.5 kg/m(2). Daytime sleepiness was the most frequent symptom (77.1%), and frequent awakening occurred in 69% of the patients. Sleep-onset insomnia and sleep-maintenance insomnia occurred in 73% and 60% of the patients, respectively. Sixty-two percent of the patients reported symptoms of RLS, which significantly correlated with sleep-onset insomnia (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.5 to 5.5; P = 0.001) and sleep-maintenance insomnia (OR, 2.1; 95% CI, 1.2 to 3.8; P = 0.014). The prevalence of OSAS was estimated by the frequency of the following symptoms: extremely loud snoring, 7 patients (3.5%); observed choking, 21 patients (10.5%); witnessed apnea, 11 patients (5.6%); snoring and witnessed apnea, 6 patients (3%); disruptive snoring, 29 patients (14.4%); and disruptive snoring and witnessed apnea, 3 patients (1.5%). This questionnaire survey confirmed a high prevalence of daytime sleepiness, insomnia, and RLS in patients with ESRF undergoing CAPD but showed a relatively low prevalence of OSAS of up to 14.4%, which may be related to the low BMI of these patients with ESRF compared with other populations. Whether this contributes to the overall better survival observed in some Asian patients with ESRF undergoing dialysis needs further investigation.

Characterization of early IgA nephropathy

Histological grading of 45 patients with clinical early immunoglobulin A (IgA) nephropathy was correlated with disease progression over a median follow-up of 123 months. Clinical early IgA nephropathy was defined as a serum creatinine level of 1.3 mg/dL or less, proteinuria of 0.4 g/d or less of protein, and the absence of hypertension at the time of renal biopsy. Disease progression was related to the occurrence of impaired renal function, increased proteinuria, and hypertension. We applied a previously described chronicity-based histological grading to the renal biopsy specimen and also assessed acute glomerular lesions. Disease progression was observed in 44.4% of these patients. Forty patients (89%) showed glomerular grade 1 (GG1) and 5 patients (11%) showed GG2, but this grading did not correlate with disease progression. However, when GG1 was subdivided into GG1a (mean sclerosis per glomerulus <10%) and GG1b (mean sclerosis per glomerulus 10% to <25%), GG1a correlated with nonprogressive disease. Tubulointerstitial grade also correlated with disease progression but was associated with a low sensitivity for predicting nonprogressive disease. Hyaline arteriolosclerosis and acute glomerular lesions did not correlate with disease progression. The chronicity-based histological grading is not only applicable to clinical early IgA nephropathy, but also more importantly, it characterizes GG1a in a subset of patients with a very low risk for disease progression, which can be regarded as genuine early IgA nephropathy.

Dialysate hyaluronan concentration predicts survival but not peritoneal sclerosis in continuous ambulatory peritoneal dialysis

Hyaluronan is an important component of extracellular matrix and plays a critical role in early phases of wound healing. Peritoneal mesothelium is a major site of hyaluronan production. Serum hyaluronan concentration has been shown to predict survival in maintenance hemodialysis patients. We hypothesize that mesothelial production of hyaluronan during the stable phase of continuous ambulatory peritoneal dialysis (CAPD) predicts the risk of peritoneal adhesion and mortality. We studied peritoneal dialysate effluent (PDE) hyaluronan levels from 116 stable CAPD patients. They were then followed-up for 3 years. During the follow-up period, there were 196 episodes of peritonitis in 78 patients. Tenckhoff catheter was removed in 31 episodes (15.8%). Tenckhoff catheter was reinserted successfully in 12 cases, and CAPD was resumed. Peritoneal adhesion developed in 16 cases. Three patients died before Tenckhoff catheter reinsertion was attempted. There was no difference in stable-phase PDE hyaluronan levels between patients who developed peritoneal adhesion and those who did not (159 +/- 63 versus 227 +/- 194 microgram/L, P = 0.27). Thirty-three patients died during the study period. Patients who died had significantly higher PDE hyaluronan concentration than survivors (272 +/- 194 versus 170 +/- 105 microgram/L, P < 0.01). Univariate analysis showed that increased PDE hyaluronan level was associated with a shorter patient survival (P < 0.001). There was no association between PDE hyaluronan level and serum albumin, protein nitrogen appearance, and percentage of lean body mass. Multivariate analysis confirmed that PDE hyaluronan level, serum albumin, and diabetic state were independent predictors of survival. We conclude that PDE hyaluronan level during stable phase of CAPD does not predict the risk of postperitonitis adhesion. However, it is a strong independent predictor of survival in CAPD patients.

Posttransplant Epstein-Barr virus-associated myogenic tumors involving bone

BACKGROUND

Epstein-Barr virus (EBV)-associated myogenic tumors in immunocompromised patients were recently recognized, but their biologic behavior remains only partially understood. Although observations so far have permitted the recognition of similarities between posttransplant myogenic tumors and posttransplant lymphoproliferative disorders (PTLD), the number of reports are still few, and new experiences continue to be informative.

METHODS

The authors describe what they believe is the first example of posttransplant EBV-associated myogenic tumor involving bone, which is also remarkable for its multicentric symmetric limb distribution. Immunohistochemistry of tumor cells for myogenic antigens (desmin and smooth muscle actin), EBV antigens (latency proteins latent membrane protein-1 [LMP-1], Epstein-Barr nuclear antigen-2 [EBNA-2], and ZEBRA), p53, and bcl-2 was examined by standard avidin-biotin-peroxidase complex methods. Molecular techniques investigated in situ hybridization for Epstein-Barr virus-encoded messenger RNAs (EBERs) and single-strand conformation polymorphism analysis for p53 mutation.

RESULTS

Although the biologic behavior of this tumor was uncertain, the reduction of immunosuppression arrested tumor growth for 5 years, at the expense of some loss in renal function. The occurrence of episodes of acute cellular rejection required pulse therapy, resulting in the appearance of new lesions in both liver and lungs. Despite these complications, a balance between control of this multicentric tumor growth and allograft survival has been maintained for 8 years.

CONCLUSIONS

To the authors' knowledge, this example of posttransplant myogenic tumor is the first described in the bone. It shows partial response to immunomodulation with persistent tumor, with prolonged survival of the renal allograft.

Importance of dialysis adequacy in mortality and morbidity of chinese CAPD patients

BACKGROUND

In continuous ambulatory peritoneal dialysis (CAPD), the impact of dialysis adequacy on patient outcome is well established in Caucasian patients but is less clear in Asian patients. Recent evidence suggests that Asian dialysis patients enjoy better overall survival. We hypothesize that dialysis adequacy may be less important in determining outcome for this ethnic group.

METHODS

We performed a single-center prospective observational study. From September 1995, we enrolled 150 existing and 120 new CAPD patients. They were followed for up to three years. We monitored dialysis adequacy and nutritional indices, including Kt/V, weekly creatinine clearance (CCr), residual glomerular filtration rate (GFR), normalized protein catabolic rate (NPCR), percentage of lean body mass (%LBM), and plasma albumin level. Clinical outcomes included mortality, technique failure, and duration of hospitalization.

RESULTS

The duration of study follow-up was 22.1 +/- 12.3 months. In our study population, 136 were male. Seventy were diabetic (25.9%), and 212 were treated with 6 L exchanges per day (78.5%). The body weight was 59.3 +/- 9.4 kg. Baseline total Kt/V was 1.78 +/- 0.41, peritoneal Kt/V 1.48 +/- 0.36, and median residual GFR 0.98 mL/min (range 0 to 7.45). Two-year patient survival was 83.0%, and technique survival was 72.8%. Multivariate analysis showed that the duration of dialysis, diabetes, %LBM, index of dialysis adequacy (Kt/V or CCr), residual GFR, and requirement of a helper for CAPD exchanges were independent factors of patient survival; serum albumin, adequacy index (Kt/V or CCr), and requirement of a helper were independent factors of technique survival. Duration of dialysis, body weight, requirement of helper, cardiovascular disease, HBsAg carrier, serum albumin, and CCr had independent effects on hospitalization. The peritoneal component of Kt/V or CCr had no independent effect on any outcome parameter. When the prevalent and new CAPD cases were analyzed separately, Kt/V predicted survival only for new CAPD cases.

CONCLUSIONS

Our results show that dialysis adequacy has significant impact on outcome of Asian CAPD patients. Although we have excellent medium-term patient and technique survival, this favorable outcome should not prevent health care workers from providing adequate dialysis to Asian patients. The reason of discrepancy in outcome between Asian and Caucasian dialysis patients requires further study.

Tissue steroid sulfatase levels, testosterone and blood pressure

The objective of this study was to examine the response of tissue steroid sulfatase (STS) levels in hypertensive rat strains, when blood pressure (BP) was lowered by different techniques at an early age. A 4x3 factoral design was used, in which males (n=6-8) from four rat strains (WKY, SHR, SHR/a, SHR/y) at 4 weeks of age, were randomly assigned to one of three treatment groups: a hydralazine group, a castration group and a control group. BP was measured by the tail cuff technique and verified by tail catheter at the end of the experiment. BP was significantly reduced by both treatments in the hypertensive strains (SHR, SHR/a, SHR/y) compared to respective control groups. At 15-17 weeks of age, animals were euthanized and heart, kidney, adrenal glands and liver were assayed for STS levels. The major trend in tissue STS was that castration significantly lowered: adrenal, heart and liver STS in specific strains. In conclusion, castration and hydralazine significantly lowered the BP in the hypertensive rat strains, but only castration consistently lowered STS levels across strains implicating testosterone as a regulator of tissue STS.

Association of plasminogen activator inhibitor-1 4G/4G genotype and type 2 diabetic nephropathy in Chinese patients

BACKGROUND

Plasminogen activator inhibitor-1 (PAI-1) is a key regulator of fibrinolytic pathway and extracellular matrix (ECM) turnover. Because diabetic nephropathy is characterized by the presence of basement membrane thickening and mesangial expansion, we examined the role of PAI-1 gene polymorphisms in the development of type 2 diabetic nephropathy. Evidence also suggested that the PA/plasmin system and the renin-angiotensin system (RAS) interact together to affect the risk of fibrosis and thrombosis. Hence, we also studied the synergistic effect between PAI-1 and angiotensin-converting enzyme (ACE) gene polymorphisms.

METHODS

The PAI-1 and ACE (D/I) gene polymorphisms were examined in a cohort of Chinese type 2 diabetic patients who had diabetes for an average of 14 years. These patients were sex and age matched. Group A (N = 46) consisted of patients without diabetic nephropathy (normoalbuminuric with creatinine <120 micromol/L), and group B (N = 95) was with diabetic nephropathy (with albuminuria or renal impairment, including patients on dialysis).

RESULTS

Patients with type 2 diabetic nephropathy had a higher frequency of PAI-1 (4G/4G) genotypes than those without nephropathy [4G/4G:4G/5G:5G/5G = 41:38:21 (%) vs. 15:65:20(%), P = 0.005]. Diabetic patients with coexistence of PAI-1 4G/4G genotype and ACE D alleles had a higher incidence of diabetic nephropathy (22 vs. 7%, P = 0.012) than those with other combinations of genotypes. Multivariate logistic regression analysis showed that PAI-1 4G/4G (P = 0.01) and the prevalence of hypertension (P < 0.0001) are independent risk factors of development of type 2 diabetic nephropathy.

CONCLUSIONS

These results suggest that the PAI-1 4G/4G genotype is associated with an increased risk for type 2 diabetic nephropathy in Chinese patients, which is an independent risk factor for the development of nephropathy. The PAI-1 4G/4G genotype also exhibits a synergistic effect with the ACE D allele on development of diabetic nephropathy.

Melatonin receptors and ligands

The goal of the article is to provide a clearer understanding of how melatonin and its related analogs interact with melatonin receptors with the hope of developing important tools and agents of significant clinical and scientific importance. The review provides a compilation of the currently published melatonergic ligands and their relative affinities for melatonin receptors and discusses the importance of developing reversible, high-affinity, and subtype selective melatonin receptor antagonists. In addition, the review discusses the utility of developing high-affinity charged melatonergic ligands and irreversible ligands. Finally, the review discusses some of the problems associated with the current models used to study receptor pharmacology and function. As the availability of tools increases in the melatonin receptor field, a great body of knowledge is also gained about the structure of the melatonin receptor and the role that specific melatonin receptor subtypes have in physiologic processes. Further design, synthesis, and application of melatonergic ligands will lead us to a clearer understanding of the role that melatonin and its receptors play in humans.

Outcome of IgA nephropathy in adults graded by chronic histological lesions

This prognostic study of primary immunoglobulin A (IgA) nephropathy focused on chronic irreversible glomerular sclerosis and interstitial fibrosis, based on the premise that this disease is characterized by a protracted and, for many, progressive course. We used a chronicity-based histological grading system to assess the biopsy specimens of 126 adults with IgA nephropathy over a median follow-up of 10 years. Our grading system included a glomerular grading (GG) of 1 to 3 based on the extent of glomerular sclerosis, a tubulointerstitial grading (TIG) of 1 to 3 based on the degree of tubular loss or interstitial fibrosis, and the evaluation of hyaline arteriolosclerosis (HA). These three histological parameters were correlated with each other and with serum creatinine level, degree of proteinuria, and blood pressure at the time of renal biopsy. Univariate analysis showed that these three histological and three clinical parameters were significantly correlated with renal survival. By multivariate analysis using the Cox regression model, GG, serum creatinine level, and degree of proteinuria represented independent prognostic factors of renal survival. For a subset of patients at a relatively early stage of disease with a serum creatinine level less than 130 micromol/L at the time of biopsy, all three histological features and degree of proteinuria were significantly correlated with renal survival, and GG was the only independent prognostic factor for renal outcome. This study shows that glomerular sclerosis represents the most important prognostic factor in adult patients with primary IgA nephropathy and has a strong predictive value. Our chronicity-based histological grading system not only correlates well with the natural history of IgA nephropathy but is also reproducible and relatively simple to apply.