Favorable outcome of Fournier gangrene in two patients with diabetes mellitus on continuous peritoneal dialysis.

Fournier gangrene (FG), a form of necrotizing fasciitis of the perineum and genitals, with high morbidity and mortality in the general population, carries the additional risk of involvement of the peritoneal catheter tunnel and peritoneal cavity in patients on chronic peritoneal dialysis (PD). We describe two men with diabetes who developed FG in the course of PD. Computed tomography showed no extension of FG to the abdominal wall, and spent peritoneal dialysate was clear in both patients. Broad-spectrum antibiotic therapy with anaerobic coverage and early aggressive debridement followed by negative-pressure wound therapy and repeated debridement led to improvements in clinical status in both cases. Surgical closure and healing of the wound was achieved in one patient; the wound of the second patient is healing, but remains open. Both patients experienced prolonged hospitalization, with a serious decline in nutrition status. In patients on PD, FG can be treated successfully. However, additional measures are required to evaluate for potential involvement of the PD apparatus and the peritoneal cavity in the infectious process; and prolonged hospitalization, worsening nutrition, and multiple surgical interventions can result.

Age, race, diabetes, blood pressure, and mortality among hemodialysis patients.

Observational studies involving hemodialysis patients suggest a U-shaped relationship between BP and mortality, but the majority of these studies followed large, heterogeneous cohorts. To examine whether age, race, and diabetes status affect the association between systolic BP (SBP; predialysis) and mortality, we studied a cohort of 16,283 incident hemodialysis patients. We constructed a series of multivariate proportional hazards models, adding age and BP to the analyses as cubic polynomial splines to model potential nonlinear relationships with mortality. Overall, low SBP associated with increased mortality, and the association was more pronounced among older patients and those with diabetes. Higher SBP associated with increased mortality among younger patients, regardless of race or diabetes status. We observed a survival advantage for black patients primarily among older patients. Diabetes associated with increased mortality mainly among older patients with low BP. In conclusion, the design of randomized clinical trials to identify optimal BP targets for patients with ESRD should take age and diabetes status into consideration.

Sources of variation in estimates of lean body mass by creatinine kinetics and by methods based on body water or body mass index in patients on continuous peritoneal dialysis.

OBJECTIVE: We identified factors that account for differences between lean body mass computed from creatinine kinetics (LBM(cr)) and from either body water (LBM(V)) or body mass index (LBM(BMI)) in patients on continuous peritoneal dialysis (CPD). DESIGN: We compared the LBM(cr) and LBM(V) or LBM(BMI) in hypothetical subjects and actual CPD patients. PATIENTS: We studied 439 CPD patients in Albuquerque, Pittsburgh, and Toronto, with 925 clearance studies. INTERVENTION: Creatinine production was estimated using formulas derived in CPD patients. Body water (V) was estimated from anthropometric formulas. We calculated LBM(BMI) from a formula that estimates body composition based on body mass index. In hypothetical subjects, LBM values were calculated by varying the determinants of body composition (gender, diabetic status, age, weight, and height) one at a time, while the other determinants were kept constant. In actual CPD patients, multiple linear regression and logistic regression were used to identify factors associated with differences in the estimates of LBM (LBM(cr)LBM(V). The differences in determinants of body composition between groups with high versus low LBM(cr) were similar in hypothetical and actual CPD patients. Multivariate analysis in actual CPD patients identified serum creatinine, height, age, gender, weight, and body mass index as predictors of the differences LBM(V)-LBM(cr) and LBM(BMI)-LBM(cr). CONCLUSIONS: Overhydration is not the sole factor accounting for the differences between LBM(cr) and either LBM(V) or LBM(BMI) in CPD patients. These differences also stem from the coefficients assigned to major determinants of body composition by the formulas estimating LBM.

Imaging of peritoneal catheter tunnel infection using positron-emission tomography.

Imaging by ultrasonography or scintigraphy may assist in the diagnosis and management of tunnel infections of the peritoneal dialysis (PD) catheter. Here, we report a case of tunnel infection in which imaging with positron-emission tomography (PET) correctly predicted failure of conservative management. A 61-year-old man with diabetic nephropathy commenced PD in January 2008. He developed erythema and drainage at the exit site, with negative cultures in February 2008, and frank exit-site infection (ESI) with purulent drainage growing methicillin-sensitive Staphylococcus aureus [MSSA (treated with 3 weeks of oral dicloxacillin)] in August 2008. Subsequently, MSSA-growing purulent drainage from the exit site persisted. Systemic antibiotics were not administered, but there was gradual improvement with gentamicin ointment alone. In November 2008, the patient developed partial extrusion of the outer cuff of the PD catheter. In January 2009, a new ESI developed. Despite a week of treatment with cefazolin and gentamicin, the patient still developed his first episode of peritonitis with coagulase-negative Staphylococcus. He then received intraperitoneal vancomycin with good response. Although the ESI appeared to have responded to the treatment, PET imaging showed increased fludeoxyglucose (FDG) activity in the whole abdominal wall portion of the PD catheter. The patient resisted removal of the catheter and had no further signs of infection until June 2009. At that time he presented with exuberant inflammatory tissue ("proud flesh") at the exit site. Repeated PET imaging again showed increased FDG activity along the abdominal wall portion of the catheter. The PD catheter was removed and found to be infected. The patient was placed on temporary hemodialysis. This case demonstrates that PET imaging, in addition to other imaging techniques, may be useful for diagnosing and managing PD catheter infections.

Dialysis-associated hyperglycemia: manifestations and treatment.

PURPOSE: Dialysis-associated hyperglycemia (DAH), is associated with a distinct fluid and electrolyte pathophysiology. The purpose of this report was to review the pathophysiology and provide treatment guidelines for DAH. METHODS: Review of published reports on DAH. Synthesis of guidelines based on these reports. RESULTS: The following fluid and solute abnormalities have been identified in DAH: (a) hypoglycemia: this is a frequent complication of insulin treatment and its prevention requires special attention. (b) Elevated serum tonicity. The degree of hypertonicity in DAH is lower than in similar levels of hyperglycemia in patients with preserved renal function. Typically, correction of hyperglycemia with insulin corrects the hypertonicity of DAH. (c) Extracellular volume abnormalities ranging from pulmonary edema associated with osmotic fluid shift from the intracellular into the extracellular compartment as a consequence of gain in extracellular solute (glucose) to hypovolemia from osmotic diuresis in patients with residual renal function or from fluid losses through extrarenal routes. Correction of DAH by insulin infusion reverses the osmotic fluid transfer between the intracellular and extracellular compartments and corrects the pulmonary edema, but can worsen the manifestations of hypovolemia, which require saline infusion. (d) A variety of acid-base disorders including ketoacidosis correctable with insulin infusion and no other interventions. (e) Hyperkalemia, which is frequent in DAH and is more severe when ketoacidosis is also present. Insulin infusion corrects the hyperkalemia. Extreme hyperkalemia at presentation or hypokalemia developing during insulin infusion require additional measures. CONCLUSIONS: In DAH, insulin infusion is the primary management strategy and corrects the fluid and electrolyte abnormalities. Patients treated for DAH should be monitored for the development of hypoglycemia or fluid and electrolyte abnormalities that may require additional treatments.

Anemia management and association of race with mortality and hospitalization in a large not-for-profit dialysis organization.

BACKGROUND: The optimal hemoglobin target and possible toxicity of epoetin therapy in hemodialysis patients are controversial. Previous studies suggest that African American patients use higher doses of epoetin and have better survival compared with white hemodialysis patients. STUDY DESIGN: Retrospective longitudinal cohort. SETTING & PARTICIPANTS: Epoetin-exposed incident hemodialysis patients (N = 12,733; African Americans, n = 4,801; white, n = 7,386) treated in Dialysis Clinic Inc facilities during 2000 to 2006. PREDICTORS: Hemoglobin, epoetin, iron. OUTCOMES: Mortality, hospitalization. MEASUREMENTS: Proportional hazards models with time-varying covariates. RESULTS: Hemoglobin concentrations less than 10 g/dL in whites and less than 11 g/dL in African Americans were associated with increased mortality and hospitalization versus the referent hemoglobin level of 11 to 11.9 g/dL. Hemoglobin levels of 13 g/dL or greater in whites were associated with decreased noncardiovascular mortality. Six-month cumulative epoetin doses of 20,000 U/wk or greater were associated with increased mortality and hospitalization versus the referent group (8,000 to 12,499 U/wk). Epoetin doses less than 8,000 U/wk were associated with decreased risk. Higher epoetin doses were associated with increased mortality at hemoglobin concentrations of 10 to 12.9 g/dL and with increased hospitalization at all hemoglobin concentrations of 10 g/dL or greater. Higher epoetin doses were associated with increased mortality and hospitalization within each tertile of serum albumin concentration. These patterns did not differ by race. LIMITATIONS: Treatment-by-indication bias and unidentified confounders cannot be excluded. Small sample sizes in the highest and lowest hemoglobin strata decrease statistical power. CONCLUSIONS: Relationships between hemoglobin concentration and mortality differed between African Americans and whites. Additionally, the relationship of lower mortality with greater achieved hemoglobin concentration seen in white patients was observed for all-cause, but not cardiovascular, mortality. A higher cumulative epoetin dose was associated with worse outcomes, even in patients with albumin levels greater than 4 g/dL. There were no statistically significant interactions between race and epoetin dose. Further studies are needed to confirm and to define the mechanism of these findings.

Scrotal edema secondary to fluid imbalance in patients on continuous peritoneal dialysis.

In addition to local causes--for example, leak of dialysate into an inguinal hernia sac or into the anterior abdominal wall through the track of the catheter for continuous peritoneal dialysis (CPD)--scrotal edema in CPD patients may result from generalized volume retention. We present 2 CPD patients with scrotal edema, illustrating the diagnosis and management of the mechanisms of volume retention. A man with hypertensive nephrosclerosis developed isolated scrotal edema 14 months after an uneventful course of continuous ambulatory peritoneal dialysis (CAPD). After repair of a ventral hernia and of a communicating hydrocele, he started continuous cycling peritoneal dialysis (CCPD), plus 2 daytime CAPD exchanges. After 4 months, he again developed isolated scrotal edema, which decreased at night. Peritoneal scintigraphy showed no dialysate leaks, and peritoneal equilibration test (PET) revealed high-average transport with a residual volume above, and an ultrafiltration volume below, the expected range. Abdominal radiography revealed migration of the CPD catheter. Malposition of the CPD catheter with positional retention of dialysate was diagnosed. The patient was treated with nightly peritoneal dialysis and no daytime exchanges. On this regimen, ultrafiltration improved and the scrotal edema disappeared with no recurrence for 5 months, at which point the patient underwent kidney transplantation. A man with diabetic nephropathy developed poor dialysate return, volume gain, and pronounced edema of the scrotum, penis, and both legs soon after starting CAPD. Peritoneal scintigraphy was negative, and abdominal radiography confirmed the appropriate position of the CPD catheter tip in the right lower abdominal quadrant. PET revealed high peritoneal solute transport, appropriate residual volume, and appropriate for the transport category, but relatively low (0.1 L), ultrafiltration volume. He was treated with a change in the CPD procedure to CCPD, plus 1 daytime icodextrin exchange and instruction to reduce salt intake. This patient has remained free of scrotal edema for 6 months. In men on CPD, scrotal edema can develop from generalized volume gain secondary to either CPD catheter malfunction or imbalance between total fluid removal and salt and water intake. Proper interpretation of PET findings is critical in the evaluation of scrotal edema not resulting from internal dialysate leaks in CPD.

Hospitalizations in patients treated sequentially by chronic hemodialysis and continuous peritoneal dialysis.

It is not established whether hospitalizations are more frequent or longer in patients on peritoneal dialysis (PD) or chronic in-center hemodialysis (HD). Comorbidity is a major factor affecting the comparison of hospitalizations. To account for comorbidity, we compared hospitalizations between the PD and HD periods in 16 patients, 8 of whom were treated by PD first (group A), and 8, by HD first (group B). In group A, causes of renal failure were diabetes (n = 3), primary renal disease (n = 2), systemic disease (n = 2), and hereditary nephropathy (n = 1). Age at onset of PD was 53 +/- 11 years; duration of PD, 31 +/- 17 months; and duration of HD, 40 +/- 33 months. This group had 52 hospitalizations in the PD period and 80 hospitalizations in the HD period. Hospitalization rate (n/ patient-year) was 2.5 +/- 2.0 during PD and 3.0 +/- 3.0 during HD (nonsignificant), and duration of hospitalization (days/patient-year) was 19.6 +/- 15.5 during PD and 21.9 +/- 17.7 during HD (nonsignificant). The three most common causes of hospitalization were peritonitis (27%), other infections (21%), and cardiovascular disease (14%) in the PD period, and HD access problems (35%), infections (16%), and cardiovascular disease (12%) in the HD period. In group B, causes of renal failure were diabetes (n = 4), primary renal disease (n = 3), and hypertension (n = 1). Age at onset of HD was 56 +/- 10 years; duration of HD, 41 +/- 19 months; and duration of PD, 60 +/- 24 months. This group had 82 hospitalizations in the HD period and 76 hospitalizations in the PD period. Hospitalization rate was 3.0 +/- 2.4 during HD and 1.9 +/- 2.8 during PD (nonsignificant), and duration of hospitalization was 17.3 +/- 25.1 during HD and 12.7 +/- 21.3 during PD (nonsignificant). The three most common causes of hospitalization were HD access problems (40%), cardiovascular disease (19%), and infections (12%) in the HD period, and other infections (36%), cardiovascular disease (19%), and peritonitis (21%) in the PD period. In patients changing dialysis modalities, rate and duration of hospitalizations did not vary between HD and PD. The causes of hospitalization were similar in the HD and PD periods regardless of which modality was applied first.

Tumoral calcinosis without hyperparathyroidism in a patient on continuous ambulatory peritoneal dialysis.

Reports of tumoral calcinosis (TC) in peritoneal dialysis (PD) patients are rare. Reported PD patients with TC also had hyperparathyroidism. A 67-year-old man on continuous ambulatory PD for almost 3 years developed TC of the right wrist and knee and both shoulders and feet. In the 2 years preceding the diagnosis of TC, this patient's serum parathyroid hormone levels were consistently low (17 +/- 12 pg/ mL). Hypercalcemia had been found in 32% of the serum samples, hyperphosphatemia in 91%, and elevated Ca x P product in 78% of the samples. At presentation with TC, serum C-reactive protein was elevated, and serum levels of vitamin D compounds were below normal. Four months after the diagnosis of TC, the patient died with a combination of gastrointestinal and retroperitoneal bleeding episodes and septic events. Tumoral calcinosis may develop in PD patients without hyperparathyroidism. Sustained hyperphosphatemia and high Ca x P product are important in the pathogenesis of uremic TC. Elevated indices of inflammation may accompany TC. Studies are needed to identify other important factors in the pathogenesis of TC in PD patients and to evaluate treatment methods.

Glomerulonephritis causing acute renal failure during the course of bacterial infections. Histological varieties, potential pathogenetic pathways and treatment.

To illustrate diagnostic approaches, potential pathogenetic differences, epidemiological implications and therapeutic dilemmas posed by glomerulonephritis (GN) with acute renal failure (ARF) complicating bacterial infections, we analyzed the course of four male patients, aged 53-71 years, who developed GN and ARF following bacterial infections. The first two patients developed GN with immunoglobulin A (IgA) deposits after infections with hospital-acquired methicillin resistant Staphylococcus aureus (MRSA). Clinical, serologic and histological features, classification of GN and treatment differed between the two patients. In the first patient, serological features (transient hypocomplementemia, normal serum protein electrophoresis) and histological findings were consistent with typical post-infectious GN. Treatment with antibiotics alone resulted in normalization of the renal function despite the severity of ARF, which required temporary hemodialysis. In the second patient, serological features (normal serum complement, polyclonal elevation of gamma globulins) and histological picture of the kidneys were characteristic of IgA nephropathy with fibrocellular crescents, and skin histology was consistent with vasculitis. Cyclophosphamide and corticosteroids were added to the antibiotics, with partial improvement of the renal failure. The third patient developed simultaneous acute rheumatic fever and post-streptococcal GN causing severe ARF requiring hemodialysis. Complete recovery of ARF and migratory polyarthritis followed initiation of corticosteroids. The fourth patient developed ARF and cerebral vasculitis following a prolonged course of Streptococcus mutans endocarditis with delayed diagnosis. He also developed multiple serological abnormalities including elevated titers of antineutrophil cytoplasmic antibodies (ANCA), antinuclear antibodies (ANA), anti-phospholipid antibodies, rheumatoid factor, and modest hypocomplementemia. Kidney biopsy revealed ANCA-mediated focal GN with 10% crescents and acute interstitial nephritis. Treatment with cyclophosphamide plus corticosteroids, but not with antibiotics alone, resulted in resolution of both the ARF and the features of cerebral vasculitis. GN following bacterial infections may have various pathogenetic mechanisms, presents complex diagnostic challenges, may be preventable in the case of hospital-acquired MRSA, and, in addition to antibiotics, may require immunosuppressive therapy in carefully selected and monitored cases.

Peritoneal dialysis as salvage renal replacement therapy after complete failure of hemodialysis access in an elderly patient with multiple comorbidities.

Although peritoneal dialysis (PD) has been advocated as a suitable substitution therapy in patients with failure of hemodialysis (HD) blood access, documentation of the performance of PD in such patients is limited. Here, we present an elderly patient with total failure of HD blood access who has had a remarkably successful course on PD. A 78-year-old man with several comorbidities started continuous ambulatory PD after a 3.5-year course of HD complicated by repeated vascular access infections and clotting episodes. These access complications resulted in 8 hospitalizations and led to inability to ambulate following a right femoral shaft fracture sustained in a fall secondary to confusion during an episode of access sepsis, and to superior vena cava (SVC) syndrome following SVC thrombosis after internal jugular catheter insertion. Over approximately 3 years, PD has been very successful in this patient, with 2 early routine episodes of peritonitis and 1 early episode of exit-site infection, control of hematologic and biochemical values, no hospitalizations in the 2.5 years before the time of writing, and good quality of life. A dedicated spouse performing the PD tasks has been a major factor in the success of PD in this patient. Peritoneal dialysis can be successful as a renal replacement procedure in incapacitated elderly patients with failure of HD blood access. In these cases, the success of PD is enhanced by dedicated family members taking on PD tasks that the patient cannot perform.

Computation of the dose of continuous peritoneal dialysis required for adequate peritoneal urea clearance without taking into account peritoneal transport indices.

To test the feasibility of calculating, in the absence of peritoneal transport studies, the dose (daily drain volume) of continuous peritoneal dialysis (CPD) that will produce a high probability of adequate fractional peritoneal urea clearance (Kpt/Vurea), we randomly separated 619 clearance studies in patients on continuous ambulatory peritoneal dialysis (CAPD) with 4 daily exchanges into a derivation (n = 322) and a validation (n = 297) group. In the derivation group, the dialysate-to-plasma urea concentration ratio (D/Purea) was < or = 0.799 within the lowest 5% of the studies. By the urea clearance formula, a D/Purea value of 0.799 will produce weekly Kpt/Vurea values of 1.70 or better if the ratio of the daily drain volume to plasma water (Dv/V) is > or = 0.304 L/L. Among the 56 studies in the validation group with Dv/V values of 0.304 L/L or more, 52 (92.9%) had weekly Kpt/Vurea values of 1.70 or better. Assuming a suitable (low) D/Purea value for a given CPD treatment, it is possible to derive the dose of dialysis (the Dv/V ratio) that will provide adequate peritoneal urea clearance levels regardless of peritoneal transport characteristics. This method is applicable to the prescription of CPD for patients lacking studies of peritoneal transport. Anuric patients on CAPD with 4 daily exchanges require a Dv/V value of 0.304 L/L or better to have a > or = 0.9 probability of achieving a weekly Kpt/Vurea of 1.70 or better.

Management of extreme azotemia from urinary tract obstruction without dialysis. Clinical correlates and kinetic modeling of the recovery of renal function.

The recovery of renal function following release of urinary tract obstruction with advanced azotemia determines both the need for emergency dialysis in the early post-obstructive period and the long-term planning for chronic kidney disease management. A man with prostatic cancer who presented with 16 days of anuria and a serum creatinine (Scr) of 42.7 mg/dl but had evidence suggesting residual renal function was managed conservatively and reached a steady-state Scr of 1.6 mg/dl within 84 h of urinary bladder catheterization. Modeling of the decrease in Scr taking into account the decline in the body creatinine pool that existed prior to the release of the obstruction and the accumulation in body fluids of creatinine produced after the release of the obstruction suggested that recovery of the value of glomerular filtration rate corresponding to the steady-state Scr occurred at the release of the urinary obstruction. The case illustrates both the clinical factors that may lead to the decision to postpone dialysis in a patient presenting with extreme obstructive azotemia and a novel method of modeling the recovery of renal function after release of the obstruction.

Advanced wasting in peritoneal dialysis patients.

AIM: To identify patients with end-stage renal disease treated by peritoneal dialysis (PD) who had zero body fat (BF) as determined by analysis of body composition using anthropometric formulas estimating body water (V) and to compare nutritional parameters between these patients and PD patients whose BF was above zero. METHODS: Body weight (W) consists of fat-free mass (FFM) and BF. Anthropometric formulas for calculating V allow the calculation of FFM as V/0.73, where 0.73 is the water fraction of FFM at normal hydration. Wasting from loss of BF has adverse survival outcomes in PD. Advanced wasting was defined as zero BF when V/0.73 is equal to or exceeds W. This study, which analyzed 439 PD patients at their first clearance study, used the Watson formulas estimating V to identify patients with VWatson/0.73 ≥ W and compared their nutritional indices with those of PD patients with VWatson/0.73 < W. RESULTS: The study identified at the first clearance study two male patients with VWatson/0.73 ≥ W among 439 patients on PD. Compared to 260 other male patients on PD, the two subjects with advanced wasting had exceptionally low body mass index and serum albumin concentration. The first of the two subjects also had very low values for serum creatinine concentration and total (in urine and spent peritoneal dialysate) creatinine excretion rate while the second subject had an elevated serum creatinine concentration and high creatinine excretion rate due, most probably, to non-compliance with the PD prescription. CONCLUSION: Advanced wasting (zero BF) in PD patients, identified by the anthropometric formulas that estimate V, while rare, is associated with indices of poor somatic and visceral nutrition.

Chronic Nephropathy from Dietary Hyperoxaluria: Sustained Improvement of Renal Function after Dietary Intervention.

A 56-year-old man with stable chronic kidney disease (CKD) for two years following a single episode of calcium oxalate urolithiasis developed progressive elevation of his serum creatinine concentration. Urinalysis revealed pyuria and white cell casts, a few red blood cells, minimal proteinuria, and no crystals. Urine culture was sterile. Gallium scintigraphy was consistent with interstitial nephritis. Proton pump inhibitor intake was discontinued, and a short course of oral corticosteroids was initiated. Percutaneous kidney biopsy, performed because of the continued deterioration of renal function to a minimum estimated glomerular filtration rate (eGFR) value of 15 mL/min per 1.73 m2 and persistent pyuria, revealed deposition of oxalate crystals in the tubules and interstitium, pronounced tubular changes, and interstitial nephritis and fibrosis. Urinary oxalate excretion was very high, in the range usually associated with primary hyperoxaluria. However, investigations for primary or enteric hyperoxaluria were negative. He reported a diet based on various nuts high in oxalate content. Estimated oxalate content in the diet was, for years, approximately four times higher than that in the average American diet. The institution of a diet low in oxalates resulted in the rapid normalization of urinary oxalate excretion and urinary sediment and in the slow, continuous improvement of renal function to near normal levels (eGFR 59 mL/min/1.73 m2) before his death from a brain malignancy 3.5 years later. The manifestations of nephropathy secondary to dietary hyperoxaluria, including the urine findings, can be indistinguishable from other types of interstitial nephritis. The diagnosis of dietary hyperoxaluria requires careful dietary history and a kidney biopsy. Identifying dietary hyperoxaluria as the cause of CKD is important because the decrease in dietary oxalate intake without any other measures can lead to sustained improvement in renal function.

Reproducibility of serial creatinine excretion measurements in peritoneal dialysis.

AIM: To test whether muscle mass evaluated by creatinine excretion (EXCr) is maintained in patients with end-stage kidney disease (ESKD) treated by peritoneal dialysis (PD), we evaluated repeated measurements of EXCr in a PD population. METHODS: One hundred and sixty-six PD patients (94 male, 72 female) receiving the same PD dose for the duration of the study (up to approximately 2.5 years) had repeated determinations of total (in urine plus spent dialysate) 24-h EXCr (EXCr T) to assess the adequacy of PD by creatinine clearance. All 166 patients had two EXCr T determinations, 84 of the 166 patients had three EXCr T determinations and 44 of the 166 patients had four EXCr T measurements. EXCr T values were compared using the paired t test in the patients who had two studies and by repeated measures ANOVA in those who were studied three or four times. RESULTS: In patients who were studied twice, with the first and second EXCr T measurements performed at 9.2 ± 15.2 mo and 17.4 ± 15.8 mo after onset of PD, respectively, EXCr T did not differ between the first and second study. In patients studied three times and whose final assessment occurred 24.7 ± 16.3 mo after initiating PD, EXCr T did not differ between the first and second study, but was significantly lower in the third study compared to the first study. In patients who were studied four times and whose fourth measurement was taken 31.9 ± 16.8 mo after onset of PD, EXCr T did not differ between any of the studies. The average EXCr T value did not change significantly, with the exception of the third study in the patients studied thrice. However, repeated determinations of EXCr T in individuals showed substantial variability, with approximately 50% of the repeated determinations being higher or lower than the first determination by 15% or more. CONCLUSION: The average value of EXCr T remains relatively constant for up to 2.5 years of follow-up in PD patients who adhere to the same PD schedule. However, repeated individual EXCr T values vary considerably in a large proportion of the patients. Further studies are needed to evaluate the clinical significance of varying EXCr T values and the stability of EXCr T beyond 2.5 years of PD follow-up.

Association between calciphylaxis and inflammation in two patients on chronic dialysis.

The pathogenesis of calciphylaxis, which has a rising incidence in the chronic dialysis population and a high mortality rate, is poorly understood. Abnormalities in the calcium-phosphorus-parathyroid axis are clinically related to calciphylaxis, but alone, they cannot explain this condition. Here, we present two patients who had chronic inflammatory conditions and hyperparathyroidism and who developed calciphylaxis. A 41-year-old white woman on hemodialysis following scleroderma, hepatitis C, liver transplant, and failed kidney transplant, developed progressive ulcerative lower extremity calciphylaxis lasting more than 3 years. She had evidence of severe hyperparathyroidism and elevated serum C-reactive protein (CRP). A 39-year-old white woman on continuous ambulatory peritoneal dialysis for 6 years for renal failure secondary to lupus nephritis, with sustained lupus activity during the dialysis period, developed rapidly progressing ulcerative calciphylaxis of the lower and upper extremities not responding to adequate treatment of hyperphosphatemia and hyperparathyroidism. Her condition culminated in death within 2 months of the appearance of the skin lesions. Her serum CRP was elevated on a sustained basis before the development of the calciphylaxis and rose to a very high level after appearance of the skin lesions. Inflammation may assist in the development of calciphylaxis through depression of serum levels of fetuin-A, an endogenous inhibitor of calcification that is also a negative acute-phase reactant. The interactions between inflammation-mediated changes in the levels of endogenous inhibitors of calcification and abnormalities in calcium-phosphorus metabolism merit intensive study in the future as potential mechanisms of calciphylaxis.

Immunoglobulin A nephropathy complicating ulcerative colitis.

Ulcerative colitis is rarely associated with immunoglobulin A nephropathy (IgAN). The development of IgA nephropathy complicates further the clinical course of patients with ulcerative colitis. A 72-year old man with a 30-year history of ulcerative colitis requiring colectomy and modest renal insufficiency secondary to complications of nephrolithiasis and renal artery stenosis developed glomerular hematuria, proteinuria and progressive renal failure. Percutaneous kidney biopsy revealed IgAN with extensive glomerular and interstitial sclerotic changes. After resection of a chronically infected ileo-rectal pouch, renal function improved, while hematuria and proteinuria gradually disappeared without specific treatment of the IgAN. The manifestations of IgAN complicating ulcerative colitis can be improved with effective treatment of the bowel disease even when there are extensive sclerotic changes in the kidneys.

BK nephropathy in the native kidneys of patients with organ transplants: Clinical spectrum of BK infection.

Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy (BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.

Lack of precision of indirect estimates of body water affects urea kinetic analysis in chronic peritoneal dialysis.

To test the precision of estimates of body water and urea clearance in peritoneal dialysis (PD), we compared, in 925 PD patients who underwent formal urea kinetics studies, estimates of V and Kt/V urea obtained by the use of the Watson, Hume, and Sahlgrenska anthropometric formulas and two novel formulas, one (Vcreat) computed using fat-free mass (FFM) estimated from creatinine kinetics as 0.73 x FFMcreat, and the other (VBMI) calculated as 0.73 x FFM(BMI) where FFM(BMI) was obtained by the Gallagher formula, which estimates body composition as a function of body mass index (BMI). Comparisons by twos were performed using the paired t-test and the Wilcoxon sign rank test with the Bonferroni correction for multiple (n=10) comparisons. The results for V (liters) were Watson, 36.7 +/- 7.1; Hume, 37.3 +/- 7.3; Sahlgrenska, 36.8 +/- 7.6; Vcreat, 32.2 +/- 9.8; and VBMP 37.2 +/- 7.8. With the exception of V(BMI) and V(Hume) which did not differ, all other values differed (p < 0.001) from one another regardless of whether a parametric or nonparametric comparison was performed. The results for weekly total Kt/V urea were Watson, 2.05 +/- 0.57; Hume, 2.03 +/- 0.57; Sahlgrenska, 2.06 +/- 0.59; from Vcreat 2.42 +/- 0.71; and from V(BMP) 2.03 +/- 0.58. All of those values differed from one another (p < 0.001) by both methods of comparison. Using cut-off values (1.50, 1.75, and 2.00) as indices of adequate total weekly Kt/V urea, the discrepancies between any two estimates by the five studied formulas varied in the range 1.1% - 34.2%. Despite numerically close mean values, estimates of V based on various anthropometric formulas differ substantially and cause substantial discrepancies in the classification of Kt/V urea as inadequate or adequate. This lack of precision, added to the known lack of accuracy of the estimates, confounds the interpretation of the clinical relevance of urea kinetic estimates in PD.