Andrew K.M. Wong

Efficacy of mycophenolate mofetil in patients with diffuse proliferative lupus nephritis

Background The combination of cyclophosphamide and prednisolone is effective for the treatment of severe lupus nephritis but has serious adverse effects. Whether mycophenolate mofetil can be substi...

Long-term follow-up of thoracoscopic pleurodesis for hydrothorax complicating peritoneal dialysis

BACKGROUNDnMassive hydrothorax is a significant complication of continuous ambulatory peritoneal dialysis (CAPD) and its ideal management remains undefined. Conservative management in the form of intermittent peritoneal dialysis had limited success. The use of conventional pleurodesis and open thoracotomy were associated with morbidities and limitations. We retrospectively reviewed the long-term outcome of 8 patients with massive hydrothorax complicating CAPD, 6 of whom received thoracoscopic pleurodesis.nnnMETHODSnAmong 397 patients undergoing continuous ambulatory peritoneal dialysis during the period from 1994 to 1998, hydrothorax developed in 8 patients. Four patients were first treated with temporary intermittent peritoneal dialysis using 1-L exchange cycles. Three of them had a recurrence of the hydrothorax whereas only one could resume continuous ambulatory peritoneal dialysis successfully. Two patients then underwent conventional pleurodesis but failed. One of them was switched to hemodialysis. Thoracoscopic pleurodesis was performed for the remaining 2 patients together with 4 other patients with hydrothorax once this complication developed. There were no gross abnormalities including pleuroperitoneal communication sites identified. Talc poudrage was performed in 2 patients and mechanical rub pleurodesis in the other 4 patients. All had uncomplicated procedure and uneventful recovery.nnnRESULTSnOne patient after thoracoscopic pleurodesis was soon switched to hemodialysis for an unrelated reason. The other 5 patients resumed continuous ambulatory peritoneal dialysis with no recurrence of hydrothorax for a mean period of 50 months (range 19 to 84).nnnCONCLUSIONSnWith thoracoscopic pleurodesis, patients resumed continuous ambulatory peritoneal dialysis without recurrence of hydrothorax on long-term follow-up.

Prevention of Recurrent Central Venous Stenosis Using Endovascular Irradiation Following Stent Placement in Hemodialysis Patients

AbstractThis study was done to evaluate the outcomenafter brachytherapy (BT) given to prevent restenosis after stentninsertion for central venous stenosis in patients with ipsilateralnhemodialysis arteriovenous fistulas (AVF). Angioplasty and stentingnwere performed on 9 primary central venous stenoses in 8 patients withnAVF followed by BT, delivering Iridium-192 radiation using annafterloading technique. BT was also administered to three patients withnfive recurrent stenoses at the stent margins. There was no residualnstenosis after angioplasty and stenting. Venographic follow-up (77-644ndays, mean 272 days) showed no restenosis in seven primary stenoses.nNew strictures (45%-100%) developed at the stent margin in six veinsn(five patients). Angioplasty or stenting was performed for five marginnstenoses in three patients, followed by a second BT. Residual stenosisnbefore BT was 0-30%. In our venographic follow-up (140-329 days,nmean 215 days), three restenoses occurred (35%-100%). All progressednto complete occlusion on later venographic follow-up irrespective ofnwhether BT was given to the stent margin or not. The mean primary andnassisted primary patency of the central veins were 359 days and 639ndays, respectively. Endovascular irradiation with a noncentering sourcendoes not prolong the patency after angioplasty and stenting of centralnvenous stenosis in hemodialysis patients.n

Clinical presentation and outcome of severe acute respiratory syndrome in dialysis patients

n Abstractn n There was a major outbreak of severe acute respiratory syndrome (SARS) affecting more than 300 patients occurring in a private housing estate in Hong Kong, in which an infected renal patient was suspected to be the primary source. It is unknown whether renal patients would represent a distinct group of patients who share some characteristics that could predispose them to have higher infectivity. In this context, we have encountered 4 dialysis patients contracting SARS in a minor outbreak, which involved 11 patients and 4 health care workers, in a medical ward of a regional hospital. Of these 4 dialysis patients, 1 patient was receiving hemodialysis while the other 3 patients were on continuous ambulatory peritoneal dialysis. Fever and radiological changes were their dominant presenting features. All were having positive results for SARS-associated coronavirus ribonucleic acid by reverse transcriptase-polymerase chain reaction performed on their nasopharyngeal aspirates or stool samples. It appeared that treatment with high-dose intravenous ribavirin and corticosteroids could only resolve the fever, but it could not stop the disease progression. All 4 patients developed respiratory failure requiring mechanical ventilation on days 9 through 12. At the end, all of the patients died from sudden cardiac arrest, which was associated with acute myocardial infarction in 2 cases. From this small case series, it appeared that dialysis patients might have an aggressive clinical course and poor outcome after contracting SARS. However, a large-scale study is required to further examine this issue, and further investigation into the immunologic abnormalities associated with the uremic state in this group of patients is also warranted.n n

Persistent Sterile Peritoneal Inflammation After Catheter Removal for Refractory Bacterial Peritonitis Predicts Full-Blown Encapsulating Peritoneal Sclerosis

♦ Background: Encapsulating peritoneal sclerosis (EPS) is the most serious complication of peritoneal dialysis, having high morbidity and mortality. To improve outcomes, early diagnosis is needed to direct treatment during the early inflammatory phase. However, in the early inflammatory phase, clinical features are nonspecific, and no reliable diagnostic criteria have been established. Because bacterial peritonitis and termination of dialysis are two important risk factors triggering the progression of EPS, patients with refractory bacterial peritonitis necessitating dialysis catheter removal are at particularly high risk of developing EPS. Many of these patients might indeed experience non-resolving sterile peritonitis (probably the inflammatory phase of EPS) before progression to full-blown disease (that is, the presence of intestinal obstruction). We undertook a retrospective study to compare, in this particular situation, the clinical characteristics of patients with or without sterile peritoneal inflammation, assessing their clinical outcomes in terms of short-term mortality and the chance of developing full-blown EPS. ♦ Methods: Our retrospective review included 62 patients whose dialysis catheter was removed because of refractory peritonitis between January 2005 and December 2010. ♦ Results: Of the 62 patients identified, 39 (63%) had persistent sterile peritoneal inflammation (“high-risk” group, n = 39), and 23 (37%) had resolution of inflammation without significant intra-abdominal collection after catheter withdrawal (“control” group, n = 23). Compared with the control group, the high-risk group had a significantly longer PD duration (71.6 ± 43.3 months vs 42.3 ± 29.9 months, p = 0.003), a higher dialysate-to-plasma ratio (D/P) of creatinine (0.768 ± 0.141 vs 0.616 ± 0.091, p = 0.004), and a higher computed tomography score for EPS (7.69 ± 2.98 vs 1.00 ± 1.00, p < 0.001). During the 6-month study period, the high-risk group had a higher chance of developing full-blown EPS (31% vs 0%, p = 0.002) and a higher 6-month all-cause mortality (36% vs 4.3%, p = 0.004). ♦ Conclusions: Persistent sterile peritoneal inflammation was common after dialysis catheter removal for refractory bacterial peritonitis, and the patients with such inflammation were at high risk of progression to full-blown EPS.

ATYPICAL MYCOBACTERIAL EXIT-SITE INFECTION AND PERITONITIS IN PERITONEAL DIALYSIS PATIENTS ON PROPHYLACTIC EXIT-SITE GENTAMICIN CREAM

We report 9 cases of exit-site infection and continuous ambulatory peritoneal dialysis peritonitis associated with atypical mycobacteria. All patients had been using topical gentamicin cream as prophylaxis for exit-site infection before the onset of these infections. Gentamicin cream is postulated to be a potential risk factor for atypical mycobacterial infection because of selective pressure on other micro-organisms. The microbiology of atypical mycobacteria and the treatment for atypical mycobacterial infections are discussed.

Risk factors and clinical course of hungry bone syndrome after total parathyroidectomy in dialysis patients with secondary hyperparathyroidism

BackgroundHungry bone syndrome (HBS) is an important postoperative complication after parathyroidectomy for severe secondary hyperparathyroidism (SHPT). There is, however, little data in the literature on its detailed clinical course, and the associated risk factors remain controversial.MethodsWe did a single-center retrospective study on 62 consecutive dialysis patients who underwent total parathyroidectomy for SHPT to examine the risk factors, clinical course and outcome. Data on demographic characteristics, perioperative laboratory parameters including serum calcium, phosphate, alkaline phosphatase (ALP) and parathyroid hormone (PTH), drug treatment for SHPT and operative details of parathyroidectomy were collected.ResultsSeventeen (27.4%) patients developed severe postoperative hypocalcemia with HBS. The serum calcium dropped progressively while serum ALP rose after operation until 2xa0weeks later when serum calcium reached the trough and serum ALP peaked. Serum phosphate also fell but stabilized between 4 and 14xa0days. The total postoperative calcium and vitamin D supplementation was significantly larger, and hospital stay was significantly longer in the group with HBS as compared with those without HBS. Young age, high body weight, high preoperative ALP level, and low preoperative calcium level independently predicted the development of HBS while preoperative PTH and use of cinacalcet or paricalcitol did not.ConclusionHBS was common after total parathyroidectomy in patients with SHPT, and it is important to closely monitor the postoperative serum calcium, phosphate and ALP levels in the following 2xa0weeks, especially for those at risk. The implications of our findings on perioperative management are discussed.

Increasing home-based dialysis therapies to tackle dialysis burden around the world: A position statement on dialysis economics from the 2nd Congress of the International Society for Hemodialysis.

Philip Kam-Tao LI, Wai Lun CHEUNG, Sing Leung LUI, Christopher BLAGG, Alan CASS, Lai Seong HOOI, Ho Yung LEE, Francesco LOCATELLI, Tao WANG, Chih-Wei YANG, Bernard CANAUD, Yuk Lun CHENG, Hui Lin CHOONG, Angel L. de FRANCISCO, Victor GURA, Kazo KAIZU, Peter G. KERR, Un I. KUOK, Chi Bon LEUNG, Wai-Kei LO, Madhukar MISRA, Cheuk Chun SZETO, Kwok Lung TONG, Kriang TUNGSANGA, Robert WALKER, Andrew Kui-Man WONG, Alex Wai-Yin YU, On Behalf of the participants of the Roundtable Discussion on Dialysis Economics in the 2nd Congress of the International Society for Hemodialysis held in Hong Kong in August 2009

Treatment with Cyclophosphamide in Elderly-Onset Nephrotic Syndrome

Background:The best treatment of elderly-onset nephrotic syndrome has not been well defined. The use of corticosteroids or combination immunosuppressants may be associated with a significant incidence of side effects in the elderly. There is little data on the use of cyclophosphamide alone. Methods:We retrospectively reviewed 30 patients with idiopathic elderly-onset nephrotic syndrome treated with cyclophosphamide. Results:Male to female ratio was 2:1, mean age at diagnosis was 72.7 ± 5.9 years and average length of follow-up was 41.4 ± 21.3 months. Significant co-morbidities, including hypertension, were present in 57%. A raised serum creatinine level was found in 57%. Biopsy revealed 15 membranous nephropathy, 4 mesangial proliferative Gn, 5 IgA nephropathy, 3 minimal change nephropathy, 2 focal segmental glomerulosclerosis and 1 C1q nephropathy. Cyclophosphamide was given for 32.0 ± 16.2 weeks with an averaged cumulative dose per patient 177 ± 84 mg/kg BW. Remission (complete or partial) was attained by 40, 63, 80 and 87% of patients within 12, 24, 36 and 48 weeks of treatment, respectively. Eighteen patients attained complete remission and 9 partial remission after treatment. The mean interval to attain first remission (complete or partial) was 18.9 ± 14.6 weeks. This was not affected by age (p = NS) or initial albumin level (p = NS). At the time of last follow-up, all but 2 patients were in complete or partial remission with raised serum creatinine levels in 40%. Conclusions:Cyclophosphamide was effective and well tolerated in the treatment of elderly-onset nephrotic syndrome, with sustained remission and preserved renal function.

Persistent hiccup in a continuous ambulatory peritoneal dialysis patient following ingestion of star fruit

Abstract Animal studies have suggested that ingestion of star fruit, which belongs to the Oxalidaceae family, may cause neurotoxicity. Outbreaks of intractable hiccups have been reported following ingestion of star fruit in patients on regular hemodialysis. Other complaints have included insomnia, agitation and mental confusion. We report a patient on continuous ambulatory peritoneal dialysis (CAPD) who presented with acute confusion and persistent hiccup following ingestion of star fruit. Symptoms resolved spontaneously. Other reported cases and management strategies are discussed.