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.

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.

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.

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.

Prolonged hypernatremia triggered by hyperglycemic hyperosmolar state with coma: A case report.

A man with past lithium use for more than 15 years, but off lithium for two years and not carrying the diagnosis of diabetes mellitus or nephrogenic diabetes insipidus (NDI), presented with coma and hyperglycemic hyperosmolar state (HHS). Following correction of HHS, he developed persistent hypernatremia accompanied by large volumes of urine with low osmolality and no response to desmopressin injections. Urine osmolality remained < 300 mOsm/kg after injection of vasopressin. Improvement in serum sodium concentration followed the intake of large volumes of water plus administration of amiloride and hydrochlorothiazide. Severe hyperglycemia may trigger symptomatic lithium-induced NDI years after cessation of lithium therapy. Patients with new-onset diabetes mellitus who had been on prolonged lithium therapy in the past require monitoring of their serum sodium concentration after hyperglycemic episodes regardless of whether they do or do not carry the diagnosis of NDI.

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.

Surgical procedures before and after starting chronic hemodialysis in a predominantly male population with high prevalence of diabetes.

PURPOSE: The purposes of this study were to analyze changes in the frequency of different categories of surgical procedures after initiation of chronic hemodialysis (HD) and to identify the types of procedures associated with in-hospital postoperative mortality. METHODS: This was a retrospective analysis of surgical procedures performed in an incident HD population of 392 patients followed in the dialysis unit of one hospital over 15 years. Among these patients, 384 were men and 258 had diabetes mellitus. At the start of HD, age of the patients was 66.3 ± 11.2 years and Charlson index 5.35 ± 2.41. Rates of procedures per patient year (n/[pt-yr]), reported as mean (95% Confidence Interval [CI]), were compared by nonparametric methods. RESULTS: In the whole HD population, the overall rate of procedures increased in the HD period (pre-HD 0.125 [95% CI 0.101-0.149] n/[pt-yr]; HD 0.928 [95% CI 0.795-1.061] n/[pt-yr]; p<0.001). The increase, noted in patients with and without diabetes, reflected increases in the rates for both vascular access and non-vascular access procedures from the pre-HD to the HD period. Amputations and surgery for hip fractures accounted for the increase in the rates of procedures related to non-vascular access. Procedures associated with mortality in the HD period included amputations, hip repair and abdominal surgery for septic conditions. CONCLUSIONS: Rates of surgical procedures for vascular access, amputations, and hip fractures ?increased after the start of HD. Amputations and hip fractures, both potentially preventable, are associated with mortality in HD patients.

Repeated intoxication presenting with azotemia, elevated serum osmolal gap, and metabolic acidosis with high anion gap: differential diagnosis, management, and prognosis.

A man with a history of alcoholism presented on two different occasions with mental changes, clinical signs of volume depletion, elevated serum osmolal gap, metabolic acidosis with high anion gap, metabolic alkalosis, hyponatremia, and azotemia after binge drinking of only ethanol. In both episodes, the serum contained ethanol, acetone, and 2-propanol (isopropanol), but no methanol or ethylene glycol. In the first episode, the rates of excretion of acetoacetate and 3-hydroxybutyrate in the urine were greatly increased. Volume repletion was the only treatment. In both episodes, azotemia and metabolic acidosis were rapidly reversed, while modest metabolic alkalosis was noted after treatment. The triad of azotemia, elevated osmolal gap, and high anion gap metabolic acidosis, which characterizes intoxication with methanol or ethylene glycol, can also develop in alcoholic ketoacidosis (AKA), an entity with substantially different management and outcome. Finding 2-propanol in the serum of patients with AKA indicates either concomitant 2-propanol ingestion or formation of 2-propanol from acetone.

Development of Renal Failure without Proteinuria in a Patient with Monoclonal Gammopathy of Undetermined Significance: An Unusual Presentation of AL Kappa Amyloidosis.

AL amyloidosis complicating monoclonal gammopathy of undetermined significance (MGUS) has usually a predominant glomerular deposition of lambda light chain. Heavy proteinuria is one of its cardinal manifestations. A 78-year-old man with a 9-year history of IgG kappa light-chain-MGUS and normal urine protein excretion developed severe renal failure. Serum levels of kappa light chain and serum IgG had been stable while proteinuria was absent throughout the nine-year period. For the first eight years, he had stable stage III chronic kidney disease attributed to bladder outlet obstruction secondary to prostatic malignancy. In the last year, he developed progressive serum creatinine elevation, without any increase in the serum or urine levels of paraproteins or any sign of malignancy. Renal ultrasound and furosemide renogram showed no evidence of urinary obstruction. Renal biopsy revealed AL amyloidosis, with reactivity exclusive for kappa light chains, affecting predominantly the vessels and the interstitium. Glomerular involvement was minimal. Melphalan and prednisone were initiated. However, renal function continues deteriorating. Deposition of AL kappa amyloidosis developing during the course of MGUS predominantly in the wall of the renal vessels and the renal interstitium, while the involvement of the glomeruli is minimal, leads to progressive renal failure and absence of proteinuria. Renal biopsy is required to detect both the presence and the sites of deposition of renal AL kappa light chain amyloidosis.

Hemodialysis catheter infection with unusual presentation and grave outcome.

Bacteremia from central venous catheter (CVC) infection causes morbidity and mortality in patients on hemodialysis (HD). Diagnosis of the infection can be difficult and may require special imaging. A 70-year-old man with diabetic nephropathy was on HD for 11 months through a permanent CVC. Because of symptomatic osteoporosis, he had kyphoplasty in three lumbar vertebrae (L2, L3, L4) 6 months after starting HD. Severe back pain persisted after kyphoplasty. Throughout the HD period, the exit site of the CVC had a clean appearance, there was no fever, and blood leukocyte counts were normal. During the 11th month of HD, he complained of subjective fever at home. Blood count revealed normal leukocyte count with neutrophilic predominance and blood cultures grew methicillin-resistant Staphylococcus aureus (MRSA). Echocardiogram revealed no heart valve vegetations, but irregular thickening of the CVC wall. Fluorodeoxyglucose positron-emission tomography-computed tomography (FDG-PET-CT) revealed severe inflammation of the CVC wall and a picture consistent with osteomyelitis and severe destruction of the body of the 11th thoracic vertebra. He was treated with intravenous vancomycin and removal of the CVC, the wall of which was grossly inflamed and grew in culture MRSA. Three weeks later, he discontinued HD because of persistent severe back pain. CVC infection with bacteremia and remote infectious foci having grave sequelae can develop in HD patients with paucity of clinical manifestations. FDG-PET-CT is a useful imaging tool in establishing the presence and extent of both the CVC infection and remote metastatic infectious foci.

Hospitalizations before and after initiation of chronic hemodialysis.

Hospitalization rate is high in patients on chronic hemodialysis (HD). We investigated whether initiation of HD changes the rate and length of hospitalization. We analyzed hospitalizations in HD patients in one hospital over 15 years. We compared annual rate and length of hospitalizations, both presented as mean (95% confidence interval [CI]) between the pre-HD and HD period. Three hundred ninety-two patients, 98% men, 59% diabetic, and 66.3 ± 11.2 years old at the onset of HD, had 1016 hospitalizations in the pre-HD period (60.0 ± 42.9 months) and 1627 hospitalizations in the HD period (32.5 ± 25.9 months). Higher values were found in the HD than the pre-HD period for rate, (pre-HD 0.557 [95% CI 0.473-0.611], HD 2.198 [95% CI 1.997-2.399] admissions/[patient-year], P<0.001) and length (pre-HD 4.63 [95% CI 3.71-5.55], HD 28.07 [95% CI 23.55-32.59] days/patient-year], P<0.001) of hospitalizations for all causes, cardiac disease, infections, vascular access, peripheral vascular disease, metabolic disturbances, gastrointestinal diseases, and miscellaneous conditions, mainly respiratory illness and malignancy. Similar differences were found when we compared the year before and the year after the start of HD. Diabetics had higher all cause rate and length of hospitalizations than non-diabetics in the pre-HD and HD periods. The rate and length of hospitalizations was higher in the HD than the pre-HD period for both HD-specific conditions and conditions encountered in both HD and general populations. Study of factors specific to HD that may affect these conditions should constitute the first step toward improving the morbidity of patients on HD.

Hospital admissions in elderly patients on chronic hemodialysis.

BACKGROUND: The purpose of this study was to determine whether number of hospital admissions per patient per year (n/[pt-yr]) and hospital days per patient per year (d/[pt-yr]) differ between elderly and younger patients on chronic hemodialysis (HD). PATIENTS AND METHODS: In a retrospective cohort analysis of incident HD patients in one dialysis unit over 15 years, we compared 166 HD patients older than 70 years (77.1 ± 4.7 yrs) at the onset of HD (group A) and 216 patients younger than 70 years both at onset (57.1 ± 7.6 yrs) and at the end of the HD period (group B). Eighty (48.2%) of group A and 141 (65.3%) patients of group B had diabetes mellitus. RESULTS: No differences were noted in the overall hospitalization rate, presented as mean, {95% Confidence interval} (group A 2.40 {2.04-2.75}, group B 2.03 {1.89-2.16} n[pt-yr]) and days/[pt-year] (group A 33.6 {25.3-41.8}, group B 24.1 {18.9-29.23}). Group A had higher number of hospitalization days (P = 0.012) for surgery or trauma and higher rate (P = 0.045) and days (P = 0.041) of hospitalization for miscellaneous causes, primarily pulmonary disease, or malignancy. Among diabetic patients, group A had only a greater number of hospital days for cardiac disease (P = 0.050). Among patients without diabetes, group A had a higher number for hospital days for surgery or trauma (P = 0.027). All other univariate comparisons were not significant. Multiple linear regression identified comorbidity, quantified by the Charlson index, Caucasian race and poor compliance with the HD schedule as predictors of admission rate and days per year for vascular access issues and comorbidity, poor compliance, and advanced age at onset of HD as predictors of admission for causes other than vascular access related. CONCLUSION: Hospitalizations, which affect quality of life, differ little between elderly and younger patients on HD. Therefore, hospitalizations do not constitute an argument for restricting access to HD to elderly patients.

Death during hospitalization in patients on chronic hemodialysis.

Mortality from various causes is higher in patients on chronic hemodialysis (HD) than in the general population. There is evidence suggesting that some of the deaths in HD patients are preventable. To identify potentially preventable causes of death, we analyzed deaths that occurred in HD patients during hospitalization over a period of 15 years. We performed a retrospective cohort analysis of 410 patients on HD for at least 6 months between 1995 and 2009 (included), who had all their hospitalizations in the same hospital. The patients were classified into 3 groups: Those who died during hospitalization (group A, n=120), those who died away from the hospital (group B, n=135), and those who were alive at the end of the observation period (group C, n=155). Continuous variables were compared between groups by the Kruskall-Wallis statistic. Logistic regression was used to identify predictors of dying during the observation period and predictors of death in the hospital. For the whole HD group of 410 patients, only 9 (2.2%) were women. 59% of the patients had diabetes mellitus. Age at the onset of HD was 65.8 ± 11.5 years and the duration of HD was 34.4 ± 27.9 months. Group A patients had a higher annual rate and duration of hospitalization and a higher Charlson comorbidity index than either of the other 2 groups, and, in comparison with patients in group C, were older at the end of observation and had a shorter duration of HD. Cardiac disease (19.2%), vascular access complications (18.3%), peripheral vascular disease (16.7%), infections (15.8%), trauma (11.7%), central nervous system disease (7.5%), respiratory failure (4.2%), malignancy (3.3%), and gastrointestinal disease (3.3%) were the causes of the last hospitalization in group A. Compared with the patients who died during hospitalization without discontinuing HD, group A patients who discontinued HD had a longer duration of their last hospitalization (52.7 ± 77.7 vs. 14.3 ± 23.8 days, P<0.001). Discontinuation of HD occurred in 80% of the hospitalizations for respiratory failure, 75% of the hospitalizations for malignancy, 57% of the hospitalizations for trauma, and 56% of the hospitalizations for central nervous system disease. Logistic regression identified a high Charlson index, advanced age, and short duration of HD as predictors of death, and an absence of diabetes, high Charlson index, prolonged annual duration of hospitalization, and short distance of the patient's domicile from the dialysis unit as predictors of death in the hospital. A substantial number of hospitalizations leading to the death of HD patients are caused by potentially preventable conditions, including vascular access complications, peripheral vascular disease, and trauma. Implementation of measures preventing these hospitalizations is a worthwhile undertaking.

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.

Increased CD36 expression signals monocyte activation among patients with type 2 diabetes.

OBJECTIVE: To explore the hypothesis that CD36, a scavenger receptor and fatty acid translocase, is upregulated in peripheral blood mononuclear cells (PBMCs) among patients with type 2 diabetes and is a biomarker of PBMC activation and inflammation. RESEARCH DESIGN AND METHODS: We used a cross-sectional observational design to study a multi-racial/ethnic population sample consisting of Caucasians, Hispanics, and Native Americans with type 2 diabetes (n = 33) and nondiabetic control subjects (n = 27). PBMC CD36 mRNA/protein and plasma high sensitivity (hs) C-reactive protein (hsCRP), hs-interleukin-6 (hsIL-6), and adiponectin were measured. RESULTS: Unadjusted PBMC CD36 mRNA and protein were 1.56- and 1.63-fold higher, respectively, among type 2 diabetic subjects versus control subjects. PBMC CD36 protein was directly associated with CD36 mRNA, plasma hsCRP, and hsIL-6 and inversely associated with plasma adiponectin in both groups. CONCLUSIONS: Increased CD36 expression is a biomarker of PBMC activation and inflammation and may become a useful tool in cardiovascular disease risk stratification.

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.

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.

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.