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C C Szeto

Publications and source records attributed to C C Szeto.

At least 19 recordsLinked to original sources
PubMed2003

A major outbreak of severe acute respiratory syndrome in Hong Kong.

BACKGROUND: There has been an outbreak of the severe acute respiratory syndrome (SARS) worldwide. We report the clinical, laboratory, and radiologic features of 138 cases of suspected SARS during a hospital outbreak in Hong Kong. METHODS: From March 11 to 25, 2003, all patients with suspected SARS after exposure to an index patient or ward were admitted to the isolation wards of the Prince of Wales Hospital. Their demographic, clinical, laboratory, and radiologic characteristics were analyzed. Clinical end points included the need for intensive care and death. Univariate and multivariate analyses were performed. RESULTS: There were 66 male patients and 72 female patients in this cohort, 69 of whom were health care workers. The most common symptoms included fever (in 100 percent of the patients); chills, rigors, or both (73.2 percent); and myalgia (60.9 percent). Cough and headache were also reported in more than 50 percent of the patients. Other common findings were lymphopenia (in 69.6 percent), thrombocytopenia (44.8 percent), and elevated lactate dehydrogenase and creatine kinase levels (71.0 percent and 32.1 percent, respectively). Peripheral air-space consolidation was commonly observed on thoracic computed tomographic scanning. A total of 32 patients (23.2 percent) were admitted to the intensive care unit; 5 patients died, all of whom had coexisting conditions. In a multivariate analysis, the independent predictors of an adverse outcome were advanced age (odds ratio per decade of life, 1.80; 95 percent confidence interval, 1.16 to 2.81; P=0.009), a high peak lactate dehydrogenase level (odds ratio per 100 U per liter, 2.09; 95 percent confidence interval, 1.28 to 3.42; P=0.003), and an absolute neutrophil count that exceeded the upper limit of the normal range on presentation (odds ratio, 1.60; 95 percent confidence interval, 1.03 to 2.50; P=0.04). CONCLUSIONS: SARS is a serious respiratory illness that led to significant morbidity and mortality in our cohort.

Adult↗
PubMed2003

Risk factors for thiazide-induced hyponatraemia.

BACKGROUND: Thiazide-induced hyponatraemia is common and potentially life threatening. In the absence of well-defined risk factors for this complication, guidelines for prescribing cannot be established. AIM: To examine whether a subgroup of patients is particularly susceptible to this complication. DESIGN: Retrospective case-control study. METHODS: We defined and recruited cases of symptomatic hyponatraemia that necessitated hospitalization from January 1996 to April 2002. Controls were selected from 8420 patients being prescribed thiazides and seen at the same institution during that period of time. RESULTS: There were 223 cases and 216 controls, with a median 115 days thiazide use. Cases were older than controls (76 +/- 9 vs. 66 +/- 13 years, p < 0.001) and lighter (52.3 +/- 10.3 vs. 63.4 +/- 3 kg, p < 0.001). By univariate analysis, serum potassium level, use of indapamide, elderly home institutionalization and physical immobility were risk factors for thiazide-induced hyponatraemia, but gender, duration of thiazide use, concomitant therapy with loop diuretics, angiotensin-converting enzyme inhibitors or non-steroidal anti-inflammatory drugs, and renal function were not. By stepwise logistic regression analysis, patient age, body weight and serum potassium were the only independent predictive factors. Each 10-year increment of age was associated with a two-fold increase in risk (hazards ratio 2.14, 95%CI 1.59-2.88). For a 5 kg increment in mass, there was a 27% decrease in odds ratio (odds ratio 0.77, 95%CI 0.68-0.87). One SD increase in serum potassium (0.84 mmol/l) was associated with a 63% decrease in risk (odds ratio 0.37, 95%CI 0.27-0.50; p < 0.0001). DISCUSSION: Hyponatraemia is a common problem after thiazide therapy. Extra caution and close monitoring are warranted when prescribing thiazides for elderly patients with low body mass.

Aged↗
PubMed2003

Is there a survival advantage in Asian peritoneal dialysis patients?

Over the last decade, epidemiological surveys and qualitative research literature have demonstrated and validated a better survival in the Asian peritoneal dialysis population. This review summarizes the current understanding of Asian peritoneal dialysis patient survival and attempts to scrutinize the supposed survival advantage of this population group. We outlined the published peritoneal dialysis survival data from a literature search, with reference to dialysis patient cohorts from 1983 through 2002 for prevalent cases and 1980 through 2002 for incident patients. Two-year and 5-year patient survival rates in excess of 80% and 60% respectively were demonstrated in Asian countries, which compared favorably with the CANUSA, ADEMEX and most Caucasian series. Better end-stage renal disease patient survival is apparent despite a dialysis adequacy disadvantage, for reasons yet to be identified. As is the case of other racial disparities in medical care, such a difference is a product of more than biological differences and include budgetary barrier, health care system and geographic variation, physician bias and statistical pitfalls. Particular efforts should therefore be made to explore the underlying reason(s) for the Asian peritoneal dialysis patient survival advantage. Alternative approach and guidelines to peritoneal dialysis delivery in Asia might be warranted.

Asia↗
PubMed2003

Mesangial lupus nephritis in Chinese is associated with a high rate of transformation to higher grade nephritis.

Mesangial lupus nephritis was thought to be a mild form of lupus nephritis. However, case reports suggest that this type of nephritis could be associated with a high rate of transformation to more serious classes. We retrospectively reviewed the clinical features, clinical response at one year following treatment, as well as the long-term outcome of patients with mesangial lupus nephritis identified on their first renal biopsy. The possible clinical parameters that may predict poor outcome were examined. Nineteen patients with a median duration of follow-up of 9.6 (2.5-11.4) years were identified. At one year after biopsy, eight patients achieved complete remission, two patients achieved partial remission and nine patients had no response. Of the 10 responders, four relapsed after a median duration of 53 (42-97) months. Nine out of 10 patients (six nonresponders and four responders who relapsed) who underwent a second biopsy showed transformation to a higher grade nephritis. The long-term outcome remained favourable in nine patients. Responders and patients who were given angiotensin-converting enzyme inhibitors were associated with favourable long-term outcome. Our data highlight that renal biopsy should be repeated early in Chinese patients with mesangial nephritis who failed to respond to treatment in order to identify those who may require intense immunosuppressive therapy.

Adolescent↗
PubMed2003

Tacrolimus in resistant primary membranous nephropathy--a report of 3 cases.

AIM: To study the efficacy and safety of tacrolimus in primary membranous nephropathy. METHOD: We describe 3 patients with primary membranous nephropathy who were either resistant to or could not tolerate steroid with or without cytotoxic agents. They were treated with tacrolimus 0.2 mg/kg/day for 6 months. The dosage of tacrolimus was adjusted to keep a whole blood tacrolimus level of 5-10 ng/ml. RESULTS: One patient had almost complete disappearance of proteinuria while the other 2 had at least 50% reduction in proteinuria. Proteinuria increased again in 2 of the patients after tacrolimus was stopped, but in neither of them proteinuria returned to the pretreatment level 6 months after tacrolimus was stopped. CONCLUSION: We conclude that tacrolimus may have a modest efficacy in the treatment of resistant membranous nephropathy.

Adult↗
PubMed2003

Parathyroid hormone and mineral metabolism do not have significant impact on pulse pressure in patients undergoing peritoneal dialysis.

BACKGROUND: Pulse pressure, a surrogate for arterial stiffness, has been shown to have substantial impact on predicting patient mortality. Excess cardiac risk in the end-stage renal disease population could be mediated by elevated arterial stiffness, which might in turn result from secondary hyperparathyroidism and abnormal calcium metabolism. METHODS: A cross-sectional study was carried out to examine a possible relationship between pulse pressure and secondary hyperparathyroidism among 126 prevalent patients undergoing continuous ambulatory peritoneal dialysis. RESULTS: The mean values for calcium and intact parathyroid hormone level were 2.48 mmol/l and 50.5 pmol/l, respectively. No correlation was found between pulse pressure and the plasma PTH levels (r = -0.15, p = 0.11) or calcium-phosphorus product (r = -0.08, p = 0.38). In a multivariate regression analysis, on the other hand, elevated pulse pressure was directly associated with age (2.1 mmHg per 10-year increase) and the presence of diabetes mellitus (6.9 mmHg) (both p < 0.001). Pulse pressure was also inversely associated with hemoglobin level. CONCLUSION: The magnitude of arterial pulse pressure in a peritoneal dialysis population was not significantly affected by parathyroid disease and alterations in mineral metabolism with end-stage renal disease. In agreement with similar observations in hemodialysis populations, it is postulated that abnormalities in conduit vessel stiffness (as measured by pulse pressure) are substantially caused by atherosclerosis, in which intimal calcification (as distinct from medial calcification in the context of hyperparathyroidism) plays a more important role.

Adult↗
PubMed2002

Unusual muscle pain in two patients with diabetic renal failure.

We report on two patients with diabetic muscle infarct, a painful musculoskeletal disorder complicating longstanding diabetes with established microangiopathy. Both patients had renal failure that was treated by dialysis. The underlying pathophysiological process was considered to be an arterial vascular event mediated through ischaemia-reperfusion injury. Clinicians should be alert to this condition. T2-weighted magnetic resonance imaging was valuable in establishing the diagnosis.

Adult↗
PubMed2001

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.

Adolescent↗
PubMed2001

Selective internal radiation therapy by yttrium-90 microspheres for hepatocellular carcinoma after renal transplantation.

We report a HBsAg-positive patient who developed hepatocellular carcinoma (HCC) 7 years after cadaveric kidney transplantation. The tumor was unresectable because of coexisting cirrhosis. Selective internal radiation (SIR) therapy, a novel therapy with the technique recently perfected, was used. Yttrium-90 microspheres were given via an angiographic catheter under fluoroscopy guidance. Serum alpha-fetal protein (AFP) was normalized within 2 wk. A follow-up abdominal CT scan revealed significant necrosis of the tumor and compensatory hypertrophy of non-diseased liver. The treatment was well tolerated except for transient liver function deterioration. The patient enjoyed 15 months of symptom-free survival before she died of liver failure. Practical aspects and potential applications of SIR therapy in this group of patients are discussed.

Adult↗
PubMed2001

Grading of acute and chronic renal lesions in Henoch-Schönlein purpura.

The renal outcome of 34 patients with Henoch-Schönlein purpura nephritis was assessed clinically and by grading acute and chronic renal lesions using a system we applied to primary IgA nephropathy. On a median follow-up period of 65 months, hypertension and the serum levels of creatinine and proteinuria at the time of renal biopsy were correlated with renal survival. Acute glomerular lesions including mesangial hypercellularity, endocapillary proliferation, necrosis, cellular crescents, and leukocytes infiltration were observed, respectively, in 41%, 12%, 50%, 29%, and 32% of the cases. Of these, only glomerular necrotizing lesion and cellular crescent were correlated with the renal survival. Chronic renal lesions based on a grading system applied to primary IgA nephropathy and assessing the extent of glomerular sclerosis (glomerular grading), of tubular loss and interstitial fibrosis (tubulointerstitial grading), and of hyaline arteriolosclerosis demonstrated correlation between these lesions, as well as with renal survival. On follow-up, these chronic renal lesions were predictors of subsequent clinical events associated with disease progression, such as impaired renal function, significant proteinuria, and development of hypertension. Despite some limitations related to the relatively small size, this series indicates that distinction of acute and chronic lesions of Henoch-Schonlein purpura nephritis is important for both the prognosis and management of patients.

Acute Disease↗
PubMed2001

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.

Adult↗
PubMed2001

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.

Biological Transport↗