Peritoneal dialysis (PD) exchange procedure is complex. Patients with cognitive impairment (CI) m... more Peritoneal dialysis (PD) exchange procedure is complex. Patients with cognitive impairment (CI) may require assistance. We studied the prevalence of CI among PD patients, its impact on PD-related peritonitis and the outcome of assisted PD. Cantonese version of Mini-Mental State examination (CMMSE) was performed in 151 patients newly started on PD. Data on patient characteristics including demographics, co-morbidities, blood parameters, medications, and number of PD-related peritonitis in the first 6 months were collected. 151 subjects were recruited. The age of studied patients was 60 ± 15.0 years, and 45 % were female. The prevalence of CI was 13.9 % using education-adjusted cut-off of CMMSE. Patients older than 65-year-old, female, and lower education level were independent risk factors for CI (OR 9.27 p = 0.001, OR 14.84 p = 0.005, and OR 6.10 p = 0.009, respectively). Age greater than 65-year old is an independent risk factor for PD-related peritonitis but CI was not. Patients requiring assisted PD were of older age (p < 0.001), lower CMMSE (p < 0.001), and scored higher for age-adjusted Charlson Co-morbidity index (p < 0.001). Compared with self-care PD patients, assisted PD patients did not have higher rates exit site infection (p = 0.30) but had a trend of higher PD peritonitis (p = 0.07). CI is common among local PD patients. Overall, CI could not be identified as an independent risk factor for PD peritonitis. There is a higher prevalence of CI among assisted PD patients but helpers may not completely eliminate the risk of PD-related peritonitis.
Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis
To determine the risk factors and outcomes of peritonitis caused by extended-spectrum beta-lactam... more To determine the risk factors and outcomes of peritonitis caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in continuous ambulatory peritoneal dialysis (CAPD). Episodes of E. coli CAPD peritonitis in our unit from October 1994 to August 2003 were reviewed. Demographic data, underlying medical conditions, recent use of gastric acid inhibitors (including H2 antagonist and proton pump inhibitor), recent antibiotic therapy, antibiotic regimen for peritonitis episodes, sensitivity test results of the E. coli isolated, and clinical outcomes were examined. Over a 10-year study period, 88 episodes of E. coli peritonitis were recorded; 11 of the 88 cases were caused by ESBL-producing E. coli. Recent use of cephalosporins and gastric acid inhibitor were associated with the development of ESBL-producing E. coil peritonitis. Compared with non-ESBL-producing E. coli peritonitis, more cases in the ESBL-producing E. coli group developed treatment failure (45.5% vs 13.0%...
Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis
We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible... more We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible ultrafiltration failure secondary to retroperitoneal leakage. The patients presented with pulmonary edema and fluid overload following a sudden onset of ultrafiltration failure on maintenance CAPD. There was no localized edema, suggesting peritoneal leakage in the abdominal wall or the perineum. Radiological examination showed no migration of the Tenckhoff catheter. Leakage of dialysate into the retroperitoneal space was only revealed by computed tomographic (CT) peritoneography. These patients were then treated with intermittent peritoneal dialysis twice weekly. After repeated CT peritoneography showing complete resolution of the leakage, they successfully resumed CAPD treatment 2 months later, without ultrafiltration problems. Our finding suggests that retroperitoneal leakage could be one of the uncommon, yet reversible, causes of acute ultrafiltration failure that can be diagnosed wi...
Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chroni... more Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chronic hepatitis C virus (HCV) infection in patients without renal failure. The optimal treatment of hepatitis C in dialysis patients remains to be established. A high incidence of adverse effects has been observed with conventional interferon and PEG-IFN alpha-2b in dialysis patients. We conducted a prospective study to investigate the tolerability and efficacy of PEG-IFN alpha-2a (135 microg weekly for 48 weeks) in six dialysis patients with chronic HCV infection. Two patients completed 48 weeks of treatment. Treatment was stopped in three patients (beyond 24 weeks) when they developed unrelated complications, and stopped in one patient due to failure of viral clearance. None required treatment discontinuation due to adverse effects, and PEG-IFN alpha-2a was subjectively well tolerated. Marrow suppression with mild anaemia, leucopenia, or thrombocytopenia remained common. Two patients (infected with genotypes 3a and 1b, respectively) had sustained virological response. Results from this pilot study showed that PEG-IFN alpha-2a appeared relatively well tolerated in dialysis patients with chronic HCV infection, and about one-third of patients could achieve sustained virological response.
The ever-growing number and increasing survival of haematopoietic stem cell transplantation (HSCT... more The ever-growing number and increasing survival of haematopoietic stem cell transplantation (HSCT) allow better recognition of its associated renal injuries. We aimed to study the clinicopathologic features of renal biopsies after HSCT by reviewing 13 percutaneous renal biopsies in our institute (Queen Mary Hospital). A retrospective clinicopathologic study of all renal biopsies archived to the Department of Pathology, Queen Mary Hospital during the period January 1999 to December 2006 was performed. Biopsies from patients with HSCT were selected. Clinical data on presentation and follow up were retrieved from hospital records and physicians. In the 8-year period, a total of 2233 native renal biopsies were archived. Thirteen renal biopsies were selected from 12 patients with HSCT (11 allogeneic, one autologous). All but one patient were male. The age at renal biopsy ranged from 7 to 63 years (median: 32 years). The median interval of renal biopsy after HSCT was 24 months (range 1-134 months). Evidence of graft-versus-host disease was found in nine patients. The most common presentation was significant proteinuria (10 cases) and renal impairment (eight cases). The predominant histological changes were membranous glomerulonephritis (n = 4) and thrombotic microangiopathy (n = 4). One case of focal segmental glomerulosclerosis, IgA nephropathy, minimal change disease, acute tubular necrosis and hypertensive nephrosclerosis were also recorded. Four of our patients died at 0-11 months after renal biopsy. Of the remaining eight patients with a mean follow up of 43.6 months (range, 10-98 months), chronic renal impairment were found in three (37.5%) patients and significant proteinuria also persisted in three. One patient had cytogenetic evidence of relapse of underlying haematological malignancy after HSCT. Among the various renal lesions after HSCT, membranous glomerulonephritis and thrombotic microangiopathy were the most common. Mechanisms of renal injury varied from graft-versus-host disease-associated immune complex deposition to non-immune complex injury on endothelial cells, glomerular epithelial cells and tubular epithelium. Pathologists and clinicians should attend to the histological and temporal heterogeneity of renal injury when managing patients after HSCT.
To compare the healthcare expenditure associated with mycophenolate mofetil (MMF)-based immunosup... more To compare the healthcare expenditure associated with mycophenolate mofetil (MMF)-based immunosuppression in contrast to conventional therapy in patients with lupus nephritis. Our retrospective single-center study compared the major healthcare costs during the first 24 months of treatment incurred by immunosuppressive medications, hospitalization, and complications in patients with severe lupus nephritis who had been treated with prednisolone and either MMF or sequential cyclophosphamide induction followed by azathioprine maintenance (CTX-AZA). Forty-four patients were studied (22 in each group). Baseline demographic and clinical measures, and remission rates after treatment, were similar between the 2 groups. Immunosuppressive drug cost was 13.6-fold higher in the MMF group (US$4168.3+/-1176.5 per patient, compared with $285.0+/-70.6 in the CTX-AZA group, mean difference $3883.2+/-251.3; p<0.001). MMF treatment was associated with a lower incidence of infections (12.0 episodes/1000 patient-months, compared with 32.4 in the CTX-AZA group; p=0.035). Combined cost of hospitalization and treatment of infections was 82.5% lower in the MMF group (mean difference -2208.7+/-1700.6; p=0.120). Overall treatment expenditure on immunosuppressive drugs, hospitalization, and treatment of infections was 1.57-fold higher in the MMF group (mean US $4635.9 compared with $2961.5 in the CTX-AZA group; p<0.001). While the cost of MMF treatment for severe lupus nephritis is much higher compared with CTX-AZA, the increased drug cost is partially offset by savings from the reduced incidence of complications.
American Journal of Respiratory and Critical Care Medicine, 2004
Severe acute respiratory syndrome (SARS) is a highly contagious and typically rapidly progressive... more Severe acute respiratory syndrome (SARS) is a highly contagious and typically rapidly progressive form of atypical pneumonia, which spread from Asia to many parts of the world in early 2003. Clinical diagnosis of SARS requires the presence of unremitting fever and progressive pneumonia despite antibiotic therapy, particularly in the presence of lymphopenia and raised transaminase levels. We report the case of a woman who had undergone a successful allogeneic bone marrow transplant for acute myeloid leukemia. She presented initially with fever and a normal chest radiograph. Her indolent clinical course of SARS was punctuated by resolution of fever, but there was progressive radiologic deterioration and increasing serum antibody titer against SARS coronavirus. Treatment with oral prednisolone and ribavirin normalized her lymphopenia, altered transaminases, chest radiograph and high-resolution computed tomography appearances rapidly. Our experience should alert other clinicians in recognizing this atypical indolent presentation of SARS, to protect health care workers and the community at large and to ensure that these patients are properly treated.
A cardiac rehabilitation and prevention program (CRPP) is a recognized nonpharmacological modalit... more A cardiac rehabilitation and prevention program (CRPP) is a recognized nonpharmacological modality in the management of coronary heart disease (CHD). However, the effect of a CRPP on systolic function of the heart is controversial, and no data exists on diastolic function in CHD. A randomized, controlled study was conducted to address these issues. Patients (n = 269) with recent acute myocardial infarction (n = 193) or after percutaneous coronary intervention (PCI) (n = 76) were randomized to either CRPP (2-hour twice-weekly exercise program for 8 weeks) or conventional therapy (control group). Serial treadmill exercise testing and at-rest echocardiography were performed during phases 1 (baseline), 2 (post-exercise training), and 3 (8-month follow up). The prevalence of left ventricular (LV) abnormal relaxation pattern (ARP) of diastolic dysfunction was increased in the control group only in phase 3 (65% vs 88%, chi2 = 7.6, P <.01). Significant improvement of individual LV diastolic parameters towards less severe delayed relaxation was also observed in the CRPP group, especially in those with recent acute myocardial infarction or ARP. The gain in exercise capacity was faster and more substantial in the CRPP than the control group (P <.001 for phase 2, P <.05 for phase 3), and was significantly correlated with LV diastolic indices in those with ARP. Exercise training had neutral effects on LV systolic function and rate-pressure product. In patients with CHD, CRPP prevented the progression of resting LV diastolic dysfunction, without affecting systolic function. In those with ARP, the improvement of diastolic function predicted the gain in exercise capacity.
Cerebrospinal fluid (CSF) Aβ42, total tau and phosphorylated tau (p-tau) are well-defined diagnos... more Cerebrospinal fluid (CSF) Aβ42, total tau and phosphorylated tau (p-tau) are well-defined diagnostic markers for Alzheimer's disease (AD). There has been no previous report of the use of these markers in the diagnosis of AD in patients with chronic kidney disease (CKD). We would like to report our preliminary findings on these biomarkers in three patients with renal failure. One patient with a clinical diagnosis of AD showed elevated CSF tau, p-tau 181, and decreased Aβ42 levels, within a similar range as in local Chinese AD patients without renal impairment. The other two delirious patients, who did not have a clinical diagnosis of AD, showed normal CSF biomarkers. We found that the diagnosis of AD with CSF biomarkers appears to be useful in renal failure patients. But our results need to be confirmed in a larger study, comparing these CSF biomarkers in AD vs. non-AD patients with concomitant CKD.
Peritoneal dialysis (PD) exchange procedure is complex. Patients with cognitive impairment (CI) m... more Peritoneal dialysis (PD) exchange procedure is complex. Patients with cognitive impairment (CI) may require assistance. We studied the prevalence of CI among PD patients, its impact on PD-related peritonitis and the outcome of assisted PD. Cantonese version of Mini-Mental State examination (CMMSE) was performed in 151 patients newly started on PD. Data on patient characteristics including demographics, co-morbidities, blood parameters, medications, and number of PD-related peritonitis in the first 6 months were collected. 151 subjects were recruited. The age of studied patients was 60 ± 15.0 years, and 45 % were female. The prevalence of CI was 13.9 % using education-adjusted cut-off of CMMSE. Patients older than 65-year-old, female, and lower education level were independent risk factors for CI (OR 9.27 p = 0.001, OR 14.84 p = 0.005, and OR 6.10 p = 0.009, respectively). Age greater than 65-year old is an independent risk factor for PD-related peritonitis but CI was not. Patients requiring assisted PD were of older age (p < 0.001), lower CMMSE (p < 0.001), and scored higher for age-adjusted Charlson Co-morbidity index (p < 0.001). Compared with self-care PD patients, assisted PD patients did not have higher rates exit site infection (p = 0.30) but had a trend of higher PD peritonitis (p = 0.07). CI is common among local PD patients. Overall, CI could not be identified as an independent risk factor for PD peritonitis. There is a higher prevalence of CI among assisted PD patients but helpers may not completely eliminate the risk of PD-related peritonitis.
Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis
To determine the risk factors and outcomes of peritonitis caused by extended-spectrum beta-lactam... more To determine the risk factors and outcomes of peritonitis caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in continuous ambulatory peritoneal dialysis (CAPD). Episodes of E. coli CAPD peritonitis in our unit from October 1994 to August 2003 were reviewed. Demographic data, underlying medical conditions, recent use of gastric acid inhibitors (including H2 antagonist and proton pump inhibitor), recent antibiotic therapy, antibiotic regimen for peritonitis episodes, sensitivity test results of the E. coli isolated, and clinical outcomes were examined. Over a 10-year study period, 88 episodes of E. coli peritonitis were recorded; 11 of the 88 cases were caused by ESBL-producing E. coli. Recent use of cephalosporins and gastric acid inhibitor were associated with the development of ESBL-producing E. coil peritonitis. Compared with non-ESBL-producing E. coli peritonitis, more cases in the ESBL-producing E. coli group developed treatment failure (45.5% vs 13.0%...
Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis
We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible... more We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible ultrafiltration failure secondary to retroperitoneal leakage. The patients presented with pulmonary edema and fluid overload following a sudden onset of ultrafiltration failure on maintenance CAPD. There was no localized edema, suggesting peritoneal leakage in the abdominal wall or the perineum. Radiological examination showed no migration of the Tenckhoff catheter. Leakage of dialysate into the retroperitoneal space was only revealed by computed tomographic (CT) peritoneography. These patients were then treated with intermittent peritoneal dialysis twice weekly. After repeated CT peritoneography showing complete resolution of the leakage, they successfully resumed CAPD treatment 2 months later, without ultrafiltration problems. Our finding suggests that retroperitoneal leakage could be one of the uncommon, yet reversible, causes of acute ultrafiltration failure that can be diagnosed wi...
Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chroni... more Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chronic hepatitis C virus (HCV) infection in patients without renal failure. The optimal treatment of hepatitis C in dialysis patients remains to be established. A high incidence of adverse effects has been observed with conventional interferon and PEG-IFN alpha-2b in dialysis patients. We conducted a prospective study to investigate the tolerability and efficacy of PEG-IFN alpha-2a (135 microg weekly for 48 weeks) in six dialysis patients with chronic HCV infection. Two patients completed 48 weeks of treatment. Treatment was stopped in three patients (beyond 24 weeks) when they developed unrelated complications, and stopped in one patient due to failure of viral clearance. None required treatment discontinuation due to adverse effects, and PEG-IFN alpha-2a was subjectively well tolerated. Marrow suppression with mild anaemia, leucopenia, or thrombocytopenia remained common. Two patients (infected with genotypes 3a and 1b, respectively) had sustained virological response. Results from this pilot study showed that PEG-IFN alpha-2a appeared relatively well tolerated in dialysis patients with chronic HCV infection, and about one-third of patients could achieve sustained virological response.
The ever-growing number and increasing survival of haematopoietic stem cell transplantation (HSCT... more The ever-growing number and increasing survival of haematopoietic stem cell transplantation (HSCT) allow better recognition of its associated renal injuries. We aimed to study the clinicopathologic features of renal biopsies after HSCT by reviewing 13 percutaneous renal biopsies in our institute (Queen Mary Hospital). A retrospective clinicopathologic study of all renal biopsies archived to the Department of Pathology, Queen Mary Hospital during the period January 1999 to December 2006 was performed. Biopsies from patients with HSCT were selected. Clinical data on presentation and follow up were retrieved from hospital records and physicians. In the 8-year period, a total of 2233 native renal biopsies were archived. Thirteen renal biopsies were selected from 12 patients with HSCT (11 allogeneic, one autologous). All but one patient were male. The age at renal biopsy ranged from 7 to 63 years (median: 32 years). The median interval of renal biopsy after HSCT was 24 months (range 1-134 months). Evidence of graft-versus-host disease was found in nine patients. The most common presentation was significant proteinuria (10 cases) and renal impairment (eight cases). The predominant histological changes were membranous glomerulonephritis (n = 4) and thrombotic microangiopathy (n = 4). One case of focal segmental glomerulosclerosis, IgA nephropathy, minimal change disease, acute tubular necrosis and hypertensive nephrosclerosis were also recorded. Four of our patients died at 0-11 months after renal biopsy. Of the remaining eight patients with a mean follow up of 43.6 months (range, 10-98 months), chronic renal impairment were found in three (37.5%) patients and significant proteinuria also persisted in three. One patient had cytogenetic evidence of relapse of underlying haematological malignancy after HSCT. Among the various renal lesions after HSCT, membranous glomerulonephritis and thrombotic microangiopathy were the most common. Mechanisms of renal injury varied from graft-versus-host disease-associated immune complex deposition to non-immune complex injury on endothelial cells, glomerular epithelial cells and tubular epithelium. Pathologists and clinicians should attend to the histological and temporal heterogeneity of renal injury when managing patients after HSCT.
To compare the healthcare expenditure associated with mycophenolate mofetil (MMF)-based immunosup... more To compare the healthcare expenditure associated with mycophenolate mofetil (MMF)-based immunosuppression in contrast to conventional therapy in patients with lupus nephritis. Our retrospective single-center study compared the major healthcare costs during the first 24 months of treatment incurred by immunosuppressive medications, hospitalization, and complications in patients with severe lupus nephritis who had been treated with prednisolone and either MMF or sequential cyclophosphamide induction followed by azathioprine maintenance (CTX-AZA). Forty-four patients were studied (22 in each group). Baseline demographic and clinical measures, and remission rates after treatment, were similar between the 2 groups. Immunosuppressive drug cost was 13.6-fold higher in the MMF group (US$4168.3+/-1176.5 per patient, compared with $285.0+/-70.6 in the CTX-AZA group, mean difference $3883.2+/-251.3; p<0.001). MMF treatment was associated with a lower incidence of infections (12.0 episodes/1000 patient-months, compared with 32.4 in the CTX-AZA group; p=0.035). Combined cost of hospitalization and treatment of infections was 82.5% lower in the MMF group (mean difference -2208.7+/-1700.6; p=0.120). Overall treatment expenditure on immunosuppressive drugs, hospitalization, and treatment of infections was 1.57-fold higher in the MMF group (mean US $4635.9 compared with $2961.5 in the CTX-AZA group; p<0.001). While the cost of MMF treatment for severe lupus nephritis is much higher compared with CTX-AZA, the increased drug cost is partially offset by savings from the reduced incidence of complications.
American Journal of Respiratory and Critical Care Medicine, 2004
Severe acute respiratory syndrome (SARS) is a highly contagious and typically rapidly progressive... more Severe acute respiratory syndrome (SARS) is a highly contagious and typically rapidly progressive form of atypical pneumonia, which spread from Asia to many parts of the world in early 2003. Clinical diagnosis of SARS requires the presence of unremitting fever and progressive pneumonia despite antibiotic therapy, particularly in the presence of lymphopenia and raised transaminase levels. We report the case of a woman who had undergone a successful allogeneic bone marrow transplant for acute myeloid leukemia. She presented initially with fever and a normal chest radiograph. Her indolent clinical course of SARS was punctuated by resolution of fever, but there was progressive radiologic deterioration and increasing serum antibody titer against SARS coronavirus. Treatment with oral prednisolone and ribavirin normalized her lymphopenia, altered transaminases, chest radiograph and high-resolution computed tomography appearances rapidly. Our experience should alert other clinicians in recognizing this atypical indolent presentation of SARS, to protect health care workers and the community at large and to ensure that these patients are properly treated.
A cardiac rehabilitation and prevention program (CRPP) is a recognized nonpharmacological modalit... more A cardiac rehabilitation and prevention program (CRPP) is a recognized nonpharmacological modality in the management of coronary heart disease (CHD). However, the effect of a CRPP on systolic function of the heart is controversial, and no data exists on diastolic function in CHD. A randomized, controlled study was conducted to address these issues. Patients (n = 269) with recent acute myocardial infarction (n = 193) or after percutaneous coronary intervention (PCI) (n = 76) were randomized to either CRPP (2-hour twice-weekly exercise program for 8 weeks) or conventional therapy (control group). Serial treadmill exercise testing and at-rest echocardiography were performed during phases 1 (baseline), 2 (post-exercise training), and 3 (8-month follow up). The prevalence of left ventricular (LV) abnormal relaxation pattern (ARP) of diastolic dysfunction was increased in the control group only in phase 3 (65% vs 88%, chi2 = 7.6, P <.01). Significant improvement of individual LV diastolic parameters towards less severe delayed relaxation was also observed in the CRPP group, especially in those with recent acute myocardial infarction or ARP. The gain in exercise capacity was faster and more substantial in the CRPP than the control group (P <.001 for phase 2, P <.05 for phase 3), and was significantly correlated with LV diastolic indices in those with ARP. Exercise training had neutral effects on LV systolic function and rate-pressure product. In patients with CHD, CRPP prevented the progression of resting LV diastolic dysfunction, without affecting systolic function. In those with ARP, the improvement of diastolic function predicted the gain in exercise capacity.
Cerebrospinal fluid (CSF) Aβ42, total tau and phosphorylated tau (p-tau) are well-defined diagnos... more Cerebrospinal fluid (CSF) Aβ42, total tau and phosphorylated tau (p-tau) are well-defined diagnostic markers for Alzheimer's disease (AD). There has been no previous report of the use of these markers in the diagnosis of AD in patients with chronic kidney disease (CKD). We would like to report our preliminary findings on these biomarkers in three patients with renal failure. One patient with a clinical diagnosis of AD showed elevated CSF tau, p-tau 181, and decreased Aβ42 levels, within a similar range as in local Chinese AD patients without renal impairment. The other two delirious patients, who did not have a clinical diagnosis of AD, showed normal CSF biomarkers. We found that the diagnosis of AD with CSF biomarkers appears to be useful in renal failure patients. But our results need to be confirmed in a larger study, comparing these CSF biomarkers in AD vs. non-AD patients with concomitant CKD.
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