Bo Ying Choy

Optimal treatment and long-term outcome of tuberculous peritonitis complicating continuous ambulatory peritoneal dialysis

A retrospective study of the treatment and short- and long-term outcomes of tuberculous peritonitis (TBP) complicating continuous ambulatory peritoneal dialysis (CAPD) among our dialysis patients over a 6-year period was performed. Ten cases of TBP complicating CAPD were identified among 601 dialysis patients between January 1988 and December 1994. There were four male and six female patients. The most common clinical features were abdominal pain, fever, and cloudy peritoneal fluid (PDF). Two patients had concurrent bacterial peritonitis. Extraperitoneal tuberculosis was not observed. The majority of the patients showed neutrophil predominance in the PDF. Only one patient had a positive acid-fast bacilli smear of the PDF. The acid-fast bacilli culture of the PDF was positive in all patients. The patients were treated with isoniazid, rifampicin, and pyrazinamide for 9 to 12 months (mean, 11 months). Continuous ambulatory peritoneal dialysis was continued in all patients. Two patients died, one from multiorgan failure at 2 months and the other from sudden cardiac death at 9 months. Two patients were converted to hemodialysis at 3 months. Six patients continued to receive CAPD after completion of the antituberculous treatment. Four of these six patients were still alive 5 years after the TBP. Three patients were still undergoing CAPD with satisfactory ultrafiltration and solute clearance. None of the patients developed relapse of TBP. We concluded that (1) TBP is a rare but important complication of CAPD, (2) removal of the Tenckhoff catheter is not mandatory in the management of TBP complicating CAPD, and (3) long-term continuation of CAPD is possible after TBP.

Hong Kong Renal Registry Report 2010

This report examines the characteristics and trends of dialysis and renal transplant patients among the resident population of Hong Kong who were managed by hospitals or dialysis centers of the Hospital Authority of Hong Kong, and who accounted for approximately 95% of all patients who received renal replacement therapy (RRT) in the territory. Patients who received RRT solely in the private sector were not included in this report. Data trends from 1996 to 2009 are presented. In 2009, 930 new patients were accepted into RRT programs and the incident rate was 132.4 patients per million population (pmp). This is lower than the incident rate in 2008, which was 148.2 pmp. The point prevalence as of December 31, 2009 was 7,580, with a prevalence rate of 1,078.8 pmp. There were 3,401 patients on peritoneal dialysis (PD, 44.9%), 945 patients on hemodialysis (HD, 12.5%), and 3,234 patients living with a functioning renal transplant. The PD to HD ratio was 81.5:18.5 for patients on dialysis treatment at Hospital Authority centers. PD-first policy continued. The overall mortality rate among RRT patients was 10.7 patients per 100 patient-years exposed. There was a decreasing trend in mortality among PD patients. Infection and cardiovascular complications were the most common causes of death. Renal transplant was the modality with the best survival. The 5-year cumulative patient survival rate for patients on transplant treatment was 88%, whereas the corresponding patient survival rates for PD and HD patients were 37% and 34.2%, respectively. More than 80% of RRT patients with reports on rehabilitation were active and had normal activities.

Immunogenicity of Intradermal Hepatitis B Vaccination in Renal Transplant Recipients

We investigated intradermal hepatitis B (HBV) vaccination in 24 renal transplant recipients who failed to develop hepatitis B surface antibody (anti‐HBs) with intramuscular (i.m.) vaccination. All patients received recombinant HBV vaccine 5 μg intradermally every 2 weeks for 8 doses. Nine patients developed protective levels of anti‐HBs (> 10 miu/mL) and two patients developed low levels of anti‐HBs (4–6 miu/mL), giving an overall initial response rate of 45.8%. A booster of 40 μg was administered intramuscularly after 1 year. All initial responders developed an anti‐HBs response (322.6 ± 92.0 miu/mL). In addition, four patients who did not respond initially to the intradermal vaccination seroconverted after the booster. Responders (62.5%) and nonresponders had comparable age, gender, immunosuppressive medications, and duration of transplant. In conclusion, renal transplant patients who fail to respond to intramuscular HBV vaccination may benefit from intradermal vaccination followed by an intramuscular booster.

Long-term outcome of renal transplant recipients with chronic hepatitis B infection-impact of antiviral treatments

Background. Antiviral treatment has improved the short-term outcome of kidney transplant recipients with chronic hepatitis B infection, but its long-term impact, especially in patients who have developed drug resistance, remains uncertain. Methods. Sixty-three hepatitis B surface antigen positive (HBsAg+) and 63 HBsAg− patients who have undergone kidney transplantation from 1985 to 2008 were retrospectively reviewed and their clinical outcomes were compared. Results. With lamivudine as initial treatment, 62% of patients developed drug resistance after 4 years. Lamivudine resistance was associated with a higher incidence of chronic hepatitis but had no significant impact on liver stiffness score or patient survival during follow-up. Salvage treatment with adefovir or entecavir was well tolerated, and resulted in a three-log decrease in hepatitis B deoxynucleic acid after 6 months and normalization of alanine aminotransferase in 75% of patients. The survival rate of HBsAg+ patients transplanted in the recent era of antiviral treatment was 81% at 10 years. Treatment of hepatitis B with nucleoside/nucleotide analogues resulted in significantly improved patient survival (83% vs. 34% at 20 years, P=0.006). Although antiviral treatment was associated with reduced mortality because of liver complications (P=0.036), liver-related deaths still accounted for 40% of mortalities in HBsAg+ patients in the era of antiviral therapies and 22.2% of all deaths that occurred in patients who had received antiviral treatment. Conclusion. Treatment of HBsAg+ renal transplant recipients with nucleoside/nucleotide analogues confers long-term survival benefit, and that rescue therapy with adefovir or entecavir is effective and well tolerated in patients who had developed resistance to lamivudine.

Hong Kong Registry Report 2004

This report is based on data (up to 31 March 2004) from the Renal Registry of the Hospital Authority of Hong Kong, and accounts for 90-95% of all patients receiving renal replacement therapy (RRT) in the territory. Patients receiving RRT in the private sector are not included in this report. The number of patients receiving RRT was 6,054 (889 per million population [pmp]), of whom 51.6% (3,123, 451 pmp) were receiving peritoneal dialysis (PD), 10.9% (662, 97 pmp) hemodialysis (HD), and 37.5% (2,269, 334 pmp) had functioning kidney transplants. The net increase from the previous year in the number of patients receiving RRT was 3.1%. The incidence of end-stage renal failure in patients undergoing RRT was 954 (140 pmp). The median ages of existing and new patients receiving RRT were 55 and 56 years, respectively. There was a trend towards an increasing number of elderly dialysis patients. Diabetes was the third major cause of renal failure among existing RRT patients and the most common cause of renal failure in new cases. The rate of serologic positivity for hepatitis B infection in RRT patients was 9.68%, while that for hepatitis C infection was 3.28%. In Hong Kong, most patients were put on PD when RRT was required. Of all patients on dialysis, 83% were on PD, of whom 94.8% were on continuous ambulatory peritoneal dialysis (CAPD). Most CAPD patients were on disconnect systems. HD was used in 17.5% of all patients on dialysis. Of the 2,269 patients with functioning kidney transplants, 836 (36.8%) were transplanted in Hong Kong. Of these, 495 (59.2%) had undergone cadaveric kidney transplantation. Of all patients receiving RRT, 30% were receiving erythropoietin. For the year ending 31 March 2004, the annual crude mortality rate for all RRT was 10% (15.3% for PD, 13% for HD, and 1.9% for transplantation). The major causes of death were infection, cardiovascular disease, and cerebrovascular accident. The 1- and 5-year survival rates for patients with kidney transplantation performed in Hong Kong between 1 April 1997 and 31 March 2003 were 98.6% and 96.5%, respectively, for living related kidney transplants, and 96.1% and 91.2%, respectively, for cadaveric kidney transplants. The 1- and 5- year graft survival rates were 91.1% and 86.1% (death censored) and 90.5% and 85.6% (death not censored) for living related kidney transplants, and 89% and 83% (death censored) and 86% and 79% (death not censored) for cadaveric kidney transplants. The overall peritonitis rate for all chronic PD systems for the year ending 31 March 2004 was one episode per 27.7 months.

Incidence and outcome of antiglomerular basement membrane disease in Chinese.

Background:  Antiglomerular basement membrane (anti‐GBM) disease is an uncommon disease, especially among Asian population. Many reports and studies on this condition in the Caucasian population are available, but little information exists on anti‐GBM disease in Asians. To study the incidence and clinical characteristics of anti‐GBM disease among Chinese patients, we reviewed our experience of anti‐GBM disease in our hospital (Queen Mary Hospital, Hong Kong) from 1992 to 2003.

Tuberculous infection in southern Chinese renal transplant recipients.

Abstract:  A retrospective study of the prevalence and pattern of tuberculosis among renal transplant patients in a single centre in southern China was performed. Twenty‐three cases of tuberculosis were diagnosed among 440 patients between January 1991 and December 2002. There were 18 men and five women. The mean age of the patients was 39.3 ± 13.4 yr. There were 13 living‐related and 10 cadaveric renal transplants. The interval between renal transplantation and the development of tuberculosis ranged from 3 to 127 months with a median of 46 months. There were 18 cases of pulmonary tuberculosis, two cases of pulmonary plus laryngeal tuberculosis, two cases of disseminated tuberculosis, and one case of tuberculosis involving the urinary tract. Diagnosis was established by positive culture for Mycobacterium tuberculosis in 21 patients and response to empirical anti‐tuberculosis treatment in two patients. The duration of symptoms before the diagnosis of tuberculosis was 27 ± 12 d. The patients were treated with standard anti‐tuberculosis drugs for 11 ± 3 months. The anti‐tuberculosis treatment was in general well‐tolerated. Five patients developed transient hepatitis, three patients developed thrombocytopenia and five patients developed gouty arthritis. One patient died 2 months after initiation of anti‐tuberculosis therapy. All other patients completed anti‐tuberculosis treatment. No recurrence of tuberculosis was observed after a median follow‐up of 90 months. We concluded that (i) tuberculosis is prevalent among southern Chinese renal transplant recipients; (ii) high index of suspicion for tuberculosis among renal transplant recipients is warranted to ensure early diagnosis and prompt initiation of treatment; and (iii) treatment with standard anti‐tuberculosis drugs for an extended period of time is well‐tolerated and is associated with favourable outcome.

CAPD-Associated Peritonitis Caused by Alcaligenes xylosoxidans sp. xylosoxidans

Alcaligenes xylosoxidans is an uncommon cause of peritonitis in patients on maintenance continuous ambulatory peritoneal dialysis (CAPD). Peritonitis caused by A. xylosoxidans usually carries a poor prognosis because of the pathogen’s virulence and its universal resistance to most antimicrobial agents. Even after early Tenckhoff catheter removal, the transport property of the peritoneum is often irreversibly damaged, leading to permanent technique failure. We report 2 patients with CAPD-associated peritonitis due to A. xylosoxidans sp. xylosoxidans who were successfully cured with a combination of piperacillin and tazobactam. One of them subsequently returned uneventfully to CAPD.

Entecavir Treatment in Kidney Transplant Recipients Infected with Hepatitis B

Although nucleotide/side analogs improve the clinical outcome of hepatitis B surface antigen‐positive (HBsAg+) kidney transplant recipients (KTR), a significant proportion of subjects have developed resistance to lamivudine (LAM). We retrospectively analyzed the efficacy and tolerability of entecavir (ETV) in HBsAg+ KTR at Queen Mary Hospital during 2005–2013. Twenty‐one patients (10 treatment‐naïve, 11 with LAM resistance) were included (duration of ETV treatment 34.7 ± 22.9 months, range 6–75 months). ETV treatment led to a decline of hepatitis B virus (HBV) DNA titer compared to baseline and is more significant in the treatment‐naïve group (treatment‐naïve: p = 0.028, <0.001 and <0.001; LAM‐resistant p = 0.273, 0.180, and 0.109 after 12, 24, and 36 months). The cumulative rate of HBV DNA undetectability at 12, 24, and 36 months was 60%, 100%, and 100% for treatment‐naïve group, and 27%, 45%, and 45% for LAM‐resistant group, respectively. Time‐to‐HBV DNA undetectability and time‐to‐alanine transaminase (ALT) normalization were 15.7 ± 4.6 and 12.6 ± 3.7 months for treatment‐naïve patients, and 24.5 ± 4.2 and 28.2 ± 3.5 months for those with LAM resistance. Genotypic resistance to ETV emerged after 20.0 ± 3.5 months with increase in ALT and HBV DNA in two patients with LAM resistance, but was not observed in the treatment‐naïve group. Allograft dysfunction, de novo cirrhosis, or hepatocellular carcinoma did not occur during follow‐up.

Renal replacement therapy for patients with diabetes mellitus in Hong Kong

Abstract Diabetes mellitus is becoming the most common cause of end-stage renal failure in Hong Kong. This review is based on data from the Hong Kong Renal Registry from 1995 through 2000. As of March 31, 2000, a total of 1026 patients with diabetes mellitus were on renal replacement therapy. A total of 809 patients had diabetic nephropathy as primary disease and 217 had diabetes mellitus as comorbidity. The prevalence of renal replacement therapy for patients with diabetes mellitus was 151 per million population. For the year ending March 31, 2000, there were 342 new patients with diabetes mellitus requiring renal replacement therapy. Of all the patients on renal replacement therapy, 23% were diabetic. The patients with diabetes mellitus were older (median age, 63 years), and had a higher incidence of hypertension (85%), ischemic heart disease (24%), cerebrovascular disease (9%), and peripheral vascular disease (3%). The modes of renal replacement therapy for patients with diabetes mellitus were peritoneal dialysis (81%), hemodialysis (9%), and transplant (10%). The annual crude mortality rate of patients with diabetes mellitus was 16% (peritoneal dialysis, 17%; hemodialysis, 18%; transplant, 1%) compared with 6% for patients without diabetes mellitus (peritoneal dialysis, 8%; hemodialysis, 12%; transplant, 1%). The major causes of death were cardiovascular disease (33%), infection (28%), and cerebrovascular event (8%). The 1-and 5-year survival rates of dibetic patient were 89% and 32% for peritoneal dialysis, 73% and 26% for hemodialysis, and 94% and 87% for transplant, respectively. The 1-and 5-year graft survival rates were 88% and 82% (death not censored), and 91% and 91% (death censored), respectively.