Predictors of peritonitis and the impact of peritonitis on clinical outcomes of continuous ambulatory peritoneal dialysis patients in Taiwan--10 years' experience in a single center

OBJECTIVE

Peritoneal dialysis (PD) has become more prevalent as a treatment modality for end-stage renal disease, and peritonitis remains one of its most devastating complications. The aim of the present investigation was to examine the frequency and predictors of peritonitis and the impact of peritonitis on clinical outcomes. ♢

METHODS

Our retrospective observational cohort study enrolled 391 patients who had been treated with continuous ambulatory PD (CAPD) for at least 90 days. Relevant demographic, biochemical, and clinical data were collected for an analysis of CAPD-associated peritonitis, technique failure, drop-out from PD, and patient mortality. ♢

RESULTS

The peritonitis rate was 0.196 episodes per patient-year. Older age (>65 years) was the only identified risk factor associated with peritonitis. A multivariate Cox regression model demonstrated that technique failure occurred more often in patients experiencing peritonitis than in those free of peritonitis (p < 0.001). Kaplan-Meier analysis revealed that the group experiencing peritonitis tended to survive longer than the group that was peritonitis-free (p = 0.11). After multivariate adjustment, the survival advantage reached significance (hazard ratio: 0.64; 95% confidence interval: 0.46 to 0.89; p = 0.006). Compared with the peritonitis-free group, the group experiencing peritonitis also had more drop-out from PD (p = 0.03). ♢

CONCLUSIONS

The peritonitis rate was relatively low in the present investigation. Elderly patients were at higher risk of peritonitis episodes. Peritonitis independently predicted technique failure, in agreement with other reports. However, contrary to previous studies, all-cause mortality was better in patients experiencing peritonitis than in those free of peritonitis. The underlying mechanisms of this presumptive "peritonitis paradox" remain to be clarified.

Clinicopathological study of originally non-lupus "full-house" nephropathy

BACKGROUND

Glomerular "full-house" immunofluorescence staining commonly indicates lupus nephritis. However, some non-lupus nephropathy also can present with a "full-house" immunofluorescence pattern mimicking lupus nephritis. The goal of this study is to define the clinicopathological spectrum of originally non-lupus "full-house" nephropathy.

METHODS

Records of 24 patients with "full-house" nephropathy in the absence of clinical or serological evidence of systemic lupus erythematosus (SLE) at the time of renal biopsy were abstracted for demographics, clinical presentation, laboratory data, renal biopsy findings, and clinical follow-up.

RESULTS

The clinicopathological diagnoses included membranous glomerulonephritis (GN) (46%), IgA nephropathy (21%), membranoproliferative GN (12.5%), postinfectious GN (12.5%), C1q nephropathy (4%), and unclassified mesangial GN (4%). No one had endothelial tubuloreticular inclusions. One patient originally diagnosed as IgA nephropathy developed anti-DNA antibody and another one patient with membranous GN developed hypocomplementemia 8 months and 10 months after renal biopsy, respectively. The two patients also developed clinical symptoms of lupus subsequently.

CONCLUSIONS

There was a broad spectrum of glomerular histological findings in non-lupus "full-house" nephropathy. The possibility of "full-house" nephropathy preceding the emergence of overt systemic lupus erythematosus remained to be elucidated.

Mean Corpuscular Volume and Mortality in Patients with CKD

BACKGROUND AND OBJECTIVES

Mean corpuscular volume is the measure of the average size of the circulatory erythrocyte, and it is principally used as an index for the differential diagnosis of anemia. Recently, mean corpuscular volume has been associated with mortality in many clinical settings. However, the association of mean corpuscular volume with mortality in patients with CKD has not been fully addressed.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a retrospective observational cohort study of 1439 patients with stages 3-5 CKD and baseline mean corpuscular volume values from 2004 to 2012 in a medical center. The study cohort was divided into the high-mean corpuscular volume group and the low-mean corpuscular volume group by the median value (90.8 fl) of mean corpuscular volume. The baseline patient information included demographic data, laboratory parameters, medications, and comorbid conditions. The independent association of mean corpuscular volume with mortality was examined using multivariate Cox regression analysis.

RESULTS

Of the 1439 participants, 234 patients (16.2%) died during a median follow-up of 1.9 years (interquartile range, 1.1-3.8 years). The crude overall mortality rate was significantly higher in the high-mean corpuscular volume group (high-mean corpuscular volume group, 22.7%; low-mean corpuscular volume group, 9.7%; P<0.001). In the fully adjusted models, the high-mean corpuscular volume group was associated with higher risks of all-cause mortality (hazard ratio, 2.19; 95% confidence interval, 1.62 to 2.96; P<0.001), cardiovascular mortality (hazard ratio, 3.57; 95% confidence interval, 1.80 to 7.06; P<0.001), and infection-related mortality (hazard ratio, 2.22; 95% confidence interval, 1.41 to 3.49; P=0.001) compared with the low-mean corpuscular volume group.

CONCLUSIONS

In patients with stages 3-5 CKD, mean corpuscular volume was associated with all-cause mortality, cardiovascular disease mortality, and infection-associated mortality, independent of other factors. The underlying pathophysiologic mechanisms warrant additional investigation.

Cerebral vasculitis and intracerebral hemorrhage in Henoch-Schönlein purpura treated with plasmapheresis

Severe neurological complications in Henoch-Schonlein purpura (HSP) are rare. We report a 13-year-old girl with HSP receiving oral steroid therapy for HSP nephritis who presented with acute onset of headache, confusion, and loss of bilateral vision. However, immediate cranial computed tomography showed merely a small intracranial hematoma in the left occipital area, which was not consistent with her clinical manifestations. The subsequent magnetic resonance imaging of the brain demonstrated bilateral, multifocal abnormalities with features consistent with cerebral vasculitis. Therapeutic plasmapheresis was performed immediately and there was rapid clinical improvement. In conclusion, we propose that plasmapheresis is a reliable and effective therapy and may be considered as the first-line treatment in this critical condition to prevent massive intracerebral hemorrhagic complication of this immune complex-mediated cerebral vasculitis leading to irreversible neurological sequelae or mortality.

Outpatient versus inpatient renal biopsy: a retrospective study

OBJECTIVE AND METHODS

There is a growing interest in the safety and efficacy of percutaneous kidney biopsy for outpatients in Taiwan. We conducted a retrospective study for patients receiving the biopsy in 2002 and 2003. Complication and mortality associated with the biopsy were compared between 147 inpatients and 183 outpatients who had been judged to need no hospitalization. All biopsies were performed using the ultrasound guidance and an automated spring-loaded biopsy device.

RESULTS

There were no death and no significant difference in complication rates between the two groups. No delayed gross hematuria, delayed pain, fever or biopsy site bleeding developed in outpatients, who were followed-up by telephone contacts for 1 - 5 days after they had been discharged. Both outpatients and inpatients with hematoma were younger than those without (p < 0.05). Template bleeding time was longer for inpatients with hematuria compared with inpatients without (12.0 vs. 5.8 minutes in average, p = 0.036), but not for outpatients (4.5 vs. 6.0 minutes in average, p = 0.282). There were moderate differences in platelet count between outpatients with hematuria and those without (p = 0.057), and in serum creatinine between inpatients with hematuria and those without (p = 0.069).

CONCLUSION

The outpatient renal biopsy appears to be equally as safe and efficient as the inpatient biopsy. However, we suggest checking template bleeding time and platelet count before biopsy for patients with clinical bleeding tendency, such as patients with a serum creatinine level over 4 mg/dl (approaching CKD stages IV, V) due to a higher risk of prolonged bleeding time. Outpatient biopsy with a 6-hour inpatient observation can be considered as a medically adequate procedure.

Minimal change nephrotic syndrome in association with strongyloidiasis

Although parasitic infections have been known to be associated with immune complex-mediated glomerular lesions, strongyloidiasis-related glomerulopathy has not been well documented. We report a patient with delayed-recognized disseminated strongyloidiasis who developed nephrotic syndrome 3 months after the beginning of the manifestations related to strongyloidiasis. A kidney biopsy showed minimal change disease. We treated strongyloidiasis and hesitated to give steroid therapy for the treatment of minimal change nephrotic syndrome (MCNS) because of the risk of aggravation of Strongyloides stercoralis infection. Surprisingly, resolution of heavy proteinuria occurred after anthelmintic therapy with ivermectin. This case suggests a possible causal relationship between S. stercoralis infection and MCNS. In addition, a review of another 4 cases previously reported in the literature demonstrates the importance of detecting underlying S. stercoralis infection in patients with nephrotic syndrome since steroid therapy can cause hyperinfection or disseminated strongyloidiasis, and which may lead to fatal outcome.

The Predictive Role of Red Cell Distribution Width in Mortality among Chronic Kidney Disease Patients

Background

Recently, accumulating evidence has demonstrated that RDW independently predicts clinically important outcomes in many populations. However, the role of RDW has not been elucidated in chronic kidney disease (CKD) patients. We conducted the present study with the aim to evaluate the predictive value of RDW in CKD patients.

Methods

A retrospective observational cohort study of 1075 stage 3–5 CKD patients was conducted in a medical center. The patients’ baseline information included demographic data, laboratory values, medications, and comorbid conditions. The upper limit of normal RDW value (14.9%) was used to divide the whole population. Multivariate Cox regression analysis was used to determine the independent predictors of mortality.

Results

Of the 1075 participants, 158 patients (14.7%) died over a mean follow-up of approximately 2.35 years. The crude mortality rate was significantly higher in the high RDW group (high RDW group, 22.4%; low RDW group 11%, p <0.001). From the adjusted model, the high RDW group was correlated with a hazard ratio of 2.19 for overall mortality as compared with the low RDW group (95% CI = 1.53–3.09, p<0.001). In addition, the high RDW group was also associated with an increased risk for cardiovascular disease (HR = 2.28, 95% CI = 1.14–4.25, p = 0.019) and infection (HR = 1.9, 95% CI = 1.15–3.14, p = 0.012)) related mortality in comparison with the low RDW group.

Conclusions

In stage 3–5 CKD patients, RDW was associated with patient mortality of all-cause, cardiovascular disease and infection. RDW should be considered as a clinical predictor for mortality when providing healthcare to CKD patients.

The negative impact of early peritonitis on continuous ambulatory peritoneal dialysis patients

BACKGROUND

Peritonitis rate has been reported to be associated with technique failure and overall mortality in previous literatures. However, information on the impact of the timing of the first peritonitis episode on continuous ambulatory peritoneal dialysis (CAPD) patients is sparse. The aim of this research is to study the influence of time to first peritonitis on clinical outcomes, including technique failure, patient mortality and dropout from peritoneal dialysis (PD).

METHODS

A retrospective observational cohort study was conducted over 10 years at a single PD unit in Taiwan. A total of 124 patients on CAPD with at least one peritonitis episode comprised the study subjects, which were dichotomized by the median of time to first peritonitis into either early peritonitis patients or late peritonitis patients. Cox proportional hazard model was used to analyze the correlation of the timing of first peritonitis with clinical outcomes.

RESULTS

Early peritonitis patients were older, more diabetic and had lower serum levels of creatinine than the late peritonitis patients. Early peritonitis patients were associated with worse technique survival, patient survival and stay on PD than late peritonitis patients, as indicated by Kaplan-Meier analysis (log-rank test, p = 0.04, p < 0.001, p < 0.001, respectively). In the multivariate Cox regression model, early peritonitis was still a significant predictor for technique failure (hazard ratio (HR), 0.54; 95% confidence interval (CI), 0.30 - 0.98), patient mortality (HR, 0.34; 95% CI, 0.13 - 0.92) and dropout from PD (HR, 0.50; 95% CI, 0.30 - 0.82). In continuous analyses, a 1-month increase in the time to the first peritonitis episode was associated with a 2% decreased risk of technique failure (HR, 0.98; 95% CI, 0.97 - 0.99), a 3% decreased risk of patient mortality (HR, 0.97; 95% CI, 0.95 - 0.99), and a 2% decreased risk of dropout from PD (HR, 98%; 95% CI, 0.97 - 0.99). Peritonitis rate was inversely correlated with time to first peritonitis according to the Spearman analysis (r = -0.64, p < 0.001).

CONCLUSIONS

Time to first peritonitis is significantly correlated with clinical outcomes of peritonitis patients with early peritonitis patients having poor prognosis. Patients with shorter time to first peritonitis were prone to having a higher peritonitis rate.

Remission of hepatitis B virus-associated membranoproliferative glomerulonephritis in a cirrhotic patient after lamivudine therapy

We describe a 39-year-old man with hepatitis B virus-(HBV) related chronic hepatitis who presented with nephrotic syndrome and decompensated cirrhosis. A kidney biopsy revealed membranoproliferative glomerulonephritis (MPGN) which was thought to be related to the HBV infection. Because interferon-alpha therapy was generally not recommended in patients with advanced liver disease, we chose lamivudine as an alternate treatment for the HBV-associated glomerulonephritis (GN). After 3-month treatment with oral lamivudine, resolution of the renal disease dramatically occurred together with improvement in liver function. To our knowledge, this is the first case of HBV-associated MPGN successfully treated with oral lamivudine therapy. The possible role of lamivudine in the treatment of HBV-associated GN is discussed.

Predictors for and impact of high peritonitis rate in Taiwanese continuous ambulatory peritoneal dialysis patients

AIM

The influence of high peritonitis rate (HPR) on clinical outcomes of continuous ambulatory peritoneal dialysis (CAPD) patients has been far less studied in the Chinese population than in those of the USA, Australia and Europe. Furthermore, concerning the peritonitis risk, most studies primarily examined the risk of developing the first peritonitis episode, rather than a HPR.

METHODS

A single-center, retrospective, observational study was carried out over 10 years in Taiwan. A total of 124 patients with at least one peritonitis episode were the study subjects. The Cox proportional hazard model was used to assess the impact of HPR on clinical outcomes. Multivariate logistic regression was conducted to determine the independent factors associated with a HPR.

RESULTS

In the multivariate Cox regression model, HPR was still a significant predictor for technique failure, patient mortality and dropout from peritoneal dialysis (PD). Factors independently associated with a HPR were peritonitis occurrence during the first year after the start of CAPD and the first peritonitis infected with streptococcus species.

CONCLUSION

Peritonitis during the first year after PD commencement and the first peritonitis infected by streptococcus species were significantly associated with an increased risk of a HPR. Our data also indicate that HPR was correlated with technique failure, patient mortality and dropout from PD, thus highlighting the need and role of future studies to reduce this complication.

Xanthogranulomatous pyelonephritis successfully treated with antibiotics only

A 73-year-old woman with leukemia presented with urinary tract infection, splenic abscess, and a renal mass. Both urine culture and pus culture of the splenic abscess yielded Klebsiella pneumoniae. Percutaneous biopsy of the renal mass confirmed the diagnosis of xanthogranulomatous pyelonephritis. Because of high risk for surgery, the patient received treatment with antibiotic therapy for 2 months. With antibiotic therapy, not only was the splenic abscess cured but follow-up ultrasonography also showed progressive resolution of the renal mass. Xanthogranulomatous pyelonephritis is frequently associated with urinary tract obstruction or nephrolithiasis. In this first report of xanthogranulomatous pyelonephritis in a patient with leukemia and splenic abscess, we provide a short review of xanthogranulomatous pyelonephritis successfully treated with antibiotics only.

The spectrum of acute renal failure in IgA nephropathy

BACKGROUND

Acute renal failure rarely complicates the course of IgA nephropathy. In this study, we have tried to define the mode of presentation, the spectrum of morphology, and the prognostic factors for renal outcome.

METHODS

Twenty patients with biopsy-proven IgA nephropathy who developed acute renal failure were identified from 2000 to 2009 at a medical center in Taiwan. The patients' records were retrospectively reviewed with respect to clinical presentation, morphology of renal biopsy, and outcomes.

RESULTS

On histology, glomerular crescents were present in 11 patients (55%), acute tubular necrosis was identified in 11 patients (55%), acute interstitial nephritis was seen in 4 patients (20%), and extensive tubular red blood cell casts were present in 4 patients (20%). At the end of follow-up, 2 patients (10%) had died, 11 patients (55%) were in remission, and 7 patients (35%) developed end-stage renal disease. The prognostic factors for renal outcome were peak serum creatinine, dialysis support requirement, morphology (prominent glomerular/tubular injury), percentage of glomeruli affected by crescents, and interstitial infiltration (p = 0.04, <0.001, 0.013, 0.05, 0.02, respectively).

CONCLUSIONS

Our findings suggested that there were four pathogenic mechanisms involved in IgA nephropathy with acute renal failure including (1) crescentic IgA nephropathy; (2) acute tubular necrosis associated with microhematuria and red blood cell casts occluding tubules; (3) acute tubular necrosis not related to microhematuria; and (4) acute interstitial nephritis, apparently induced by drugs. In general, patients with prominent tubular injury had a much higher remission rate than patients with prominent glomerular injury.

Antibiotic lock technique reduces the incidence of temporary catheter-related infections

BACKGROUND

In the hemodialytic population, infections are the second leading cause of death; access infections account for a large proportion of this mortality. The antibiotic lock technique has been applied to infected tunneled catheters as rescue or prophylaxis medication to reduce infection rates. In addition, application of topical antibiotic ointments to tunneled and non-tunneled catheters also prevents exit site infections.

METHODS

17 patients with 25 catheters participated in our study from March 2004 - February 2005. The catheter lock comprised of mixed cefazolin (5 mg/dl) with heparin (2,500 IU/ml) and mupirocin was topically applied to the area (2 x 2 cm) surrounding the catheter exit site.

RESULTS

The catheter infection rate was reduced from 12.7 times/1,000 catheter days to 5.02 times/1,000 catheter days in patients with jugular vein catheters. The total catheter-related infection rate was 14.9 times/1,000 catheter days in the control group and 4.1 times/1,000 catheter days in the study group. The reduction in catheter infections was more evident in a subgroup of non-diabetic patients, and in those with femoral catheters.

CONCLUSION

The use of antibiotic lock and topical antibiotics significantly reduces the incidence of temporary catheter-related infections, especially in non-diabetic patients and in those with femoral catheters.

Focal segmental glomerulosclerosis in association with Cushing's disease

Focal segmental glomerulosclerosis (FSGS) may be idiopathic or secondary to a variety of causes. Clinical distinction between primary and secondary forms of FSGS has crucial therapeutic consequences. Whereas the former may respond to immunosuppressive therapy, treatment of secondary forms of FSGS must aim to resolve the underlying diseases. Although the combination of nephrotic syndrome and Cushing's syndrome has been described anecdotally, the causal relationship between these two diseases remains controversial. We report herein a 37-year-old man who presented with lower extremity pitting edema. Heavy proteinuria and mild renal insufficiency prompted to perform a kidney biopsy and the specimen showed FSGS. On the other hand, admission physical examination was notable for a Cushingoid appearance. After endocrinological investigations, the patient was diagnosed as having Cushing's disease caused by pituitary adrenocorticotropic hormone-producing microadenoma. Immunosuppressive therapy for the treatment of FSGS was not carried out and we treated his Cushing's disease with transsphenoidal resection of the pituitary microadenoma. Surprisingly, resolution of heavy proteinuria occurred when the patient's physical features characteristic of Cushing's disease were gradually resolved 3 months later. This case suggests a possible association of Cushing's disease with FSGS.

Differences in new-onset IgA nephropathy between young adults and the elderly

BACKGROUND

The goal of this study was to define the clinical and histological differences in new-onset IgA nephropathy between young adults and the elderly.

METHODS

We retrospectively examined renal biopsy findings, clinical features at presentation and outcomes in 82 young adults (mean age 30.3+/-10.2 years) and 17 elderly patients (mean age 71.9+/-4.5 years) with IgA nephropathy whose renal biopsies were taken within 1 year from the onset of renal manifestations.

RESULTS

The elderly group more frequently had hypertension (p<0.001), acute renal failure (p<0.001), and nephrotic range proteinuria (p=0.001) at presentation than the young adults group. On histology, a higher percentage of globally sclerotic glomeruli (p<0.001) was present in the elderly group. In patients presenting with acute renal failure, the elderly group more frequently had an intercurrent disease (p=0.02), mostly infection, and a higher mortality rate (p=0.033). On histology, the young adults group had a higher percentage of glomeruli affected by crescents (p=0.027); in contrast, the elderly group more commonly had acute tubular injury (p=0.02).

CONCLUSIONS

The elderly patients affected by IgA nephropathy had more severe renal manifestations at presentation (acute renal failure in 52.9% and nephrotic syndrome in 41.2% of patients). In cases of acute renal failure, the elderly patients had more predominant tubular rather than glomerular injury. Moreover, the considerable mortality rate (44.4%) might be associated with the intercurrent disease, mostly infection, which was more commonly present in the elderly patients.

Sustained low-efficiency daily diafiltration with hemoperfusion as a therapy for severe star fruit intoxication: a report of two cases

Over the past decade, star fruit (Averrhoa carambola) intoxication decreased in the Taiwanese society due to improved public education on chronic kidney disease (CKD). Various complications including hiccups, altered levels of consciousness, coma, and seizures have been reported in individuals with renal failure who ingested fresh star fruit or star fruit juice. A high mortality rate (from 33 to 80%) was observed in patients with altered levels of consciousness, despite prompt dialysis and supportive care. According to previous case reports, the proposed treatment of choice for severe star fruit intoxication may be continuous renal replacement therapy with or without hemoperfusion. We report two cases of star fruit intoxication with stage V CKD (one case is predialysis) presenting with coma and generalized tonic-clonic seizures. The two patients were treated with sustained low-efficiency daily diafiltration (SLEDD-f) and charcoal hemoperfusion. Status epilepticus was controlled fairly quickly after treatment with SLEDD-f and hemoperfusion. However, the outcomes in this report are still poor (both remained comatose; one of two patients died). Currently, there are no data for the use of SLEDD-f with hemoperfusion for severe star fruit intoxication. SLEDD-f with charcoal hemoperfusion may play a role in managing refractory status epilepticus in patients with severe star fruit poisoning.

Transformation from tubulointerstitial nephritis to crescentic glomerulonephritis: an unusual presentation of ANCA-associated renal vasculitis

A 44-year-old man with acute renal failure and antineutrophil cytoplasmic antibodies (ANCA) positivity was described. The first renal biopsy specimen showed tubulointerstitial nephritis (TIN) with normal glomeruli. However, delayed recovery of renal function with low-dose steroid treatment for TIN prompted a second renal biopsy 1 month later; and the specimen demonstrated a dramatically different morphology, with necrotizing and crescentic glomerulonephritis. Improvement in renal function occurred, together with reduction of ANCA titers, following intensive immunosuppressive therapy. This case illustrates an unusual presentation of TIN in ANCA-associated renal vasculitis. The possible pathogenetic mechanism are discussed.

Emphysematous pyelonephritis presenting as necrotizing fasciitis of the leg

We report a 50-year-old man with poorly controlled diabetes mellitus who presented with a painful, swollen right leg. He had also experienced right flank pain for 1 week prior to admission. Physical examination was notable for tenderness over the right flank. The right leg was diffusely swollen and exquisitely tender to touch, with palpable crepitance. Laboratory tests revealed leukocytosis and pyuria. Computed tomography showed a right ureteral stone with hydronephrosis and characteristic findings of emphysematous pyelonephritis. Furthermore, a right perirenal gas-forming abscess with extension to the right leg was noted. The patient was successfully treated with antibiotic therapy, aggressive control of blood sugar, percutaneous drainage of the hydronephrosis and perirenal abscess, and aggressive debridement of the leg.