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A Vychytil

Publications and source records attributed to A Vychytil.

At least 19 recordsLinked to original sources

Adequacy of automated peritoneal dialysis with and without manual daytime exchange: A randomized controlled trial.

Until now, it remains unclear whether the addition of manual daytime exchanges or increasing the nightly dialysate flow is the best strategy to optimize automated peritoneal dialysis (APD) treatment. In this open-label randomized controlled crossover trial, 18 patients with high-average (HA) or low-average (LA) peritoneal transport rates sequentially underwent two different APD regimens for 7 days each, with an intermittent washout period of 7 days. 'Manual exchange' treatment was a conventional APD with low nightly dialysate flow and one manual daytime exchange. 'High-flow' treatment was defined by cycler therapy with high dialysate flow but without manual daytime exchange. Creatinine clearances (8.56+/-1.22 vs 7.87+/-1.04 l/treatment, P = 0.011) and urea nitrogen clearances (12.83+/-1.98 vs 11.68+/-1.06 l/treatment, P = 0.014) were significantly increased during 'high-flow' treatment compared to 'manual exchange' treatment. Sodium removal was significantly lower and glucose absorption was higher with the 'high-flow' regimen. Phosphate clearances, beta2-microglobulin clearances, ultrafiltration, and peritoneal protein loss were not different between the two treatment modalities. Subgroup analysis dependent on peritoneal transport types showed that the effect on clearances was most marked and significant in HA transporters, whereas sodium removal was lowest in LA transporters. We conclude that small solute clearances can be significantly improved and middle molecule clearances maintained in APD patients by increasing the nightly dialysate flow instead of adding a manual daytime exchange. However, the possible benefit of better clearances with higher nightly treatment volumes has to be weighed against increased costs and the possible negative impact of impaired sodium removal, especially in LA transporters.

Adult↗

The role of peritoneal dialysis in the management of treatment-resistant congestive heart failure: A European perspective.

Patients with congestive heart failure (CHF) resistant to conventional treatment have a poor prognosis. Extracorporeal ultrafiltration (UF) appears to be the therapy of choice for short-term management of such patients with severe fluid overload, whereas peritoneal dialysis (PD) may be the therapy of choice for the long-term treatment. Fluid removal results in reduction of plasma volume, improvement of hyponatremia, reduction in pulmonary capillary wedge pressure, improvement of New York Heart Association functional heart failure class, improvement of functional rehabilitation and quality of life, reduction of hospitalizations and readmissions, as well as improvement in diuretic responsiveness. Whether extracorporeal UF and/or PD modifies the survival rate of patients with refractory CHF needs to be determined in prospective randomized controlled trials.

Europe↗

The role of tidal peritoneal dialysis in modern practice: A European perspective.

Tidal peritoneal dialysis (TPD) has been introduced to optimize adequacy of peritoneal dialysis (PD). Early studies reported similar or even better small solute clearances with TPD than those achieved with continuous ambulatory peritoneal dialysis or continuous cyclic peritoneal dialysis. However, in many studies treatment volumes were much higher during TPD compared with other PD modalities. Based on current evidence, TPD provides no advantage of increased small solute clearances, middle molecule clearances, or peritoneal ultrafiltration as compared to non-tidal automated peritoneal dialysis (APD) when dialysate flow is kept constant. However, TPD reduces drainage pain and nightly alarms during cycler treatment. Tidal volume should be kept as high as possible in these patients, especially in those with low average peritoneal transport rates. Based on theoretical considerations and little evidence, TPD could provide better clearances than conventional APD when a very high dialysate flow (>or=5 l/h) is used. Such dialysate flow rates are not routinely prescribed in home APD patients. However, they may be interesting for in-center PD patients. One randomized crossover trial reported higher small solute clearances with TPD compared to non-tidal APD in patients with acute renal failure. TPD is also the preferred treatment modality in patients with ascites as it allows a controlled outflow of fluid from the peritoneal cavity. Newer treatment modalities, for example, continuous flow PD, may be interesting alternatives in an effort to increase efficacy of PD in the future. However, because such treatment regimens are expensive and elaborate they have not been established for routine use until now.

Dialysis Solutions↗

A case of continuous ambulatory peritoneal dialysis peritonitis with an uncommon organism and an atypical clinical course.

This report describes a 46-year-old patient who experienced an atypical course of peritonitis while undergoing continuous ambulatory peritoneal dialysis (CAPD). The first sign of peritonitis was progressive impairment of ultrafiltration with increasing fluid absorption. The patient came to the center after 5 days with leg edemas and 645 leukocytes/microL in the first dialysate outflow. On the same day, the dialysate cell count decreased to 208/microL. During the following days, ultrafiltration failure persisted despite spontaneous normalization of PD-fluid leukocytes. No other clinical symptoms were observed, and the serum C-reactive protein (CRP) level remained normal. Magnetic resonance peritoneography and abdominal radiograph did not show dislocation of the catheter, a dialysate leak, or other causes of ultrafiltration failure. At day 14, fever, diarrhea, and an elevated serum CRP level occurred. Dialysate cultures taken on days 8, 11, and 14 showed growth of NEISSERIA: sicca. After initiation of antibiotic therapy with levofloxacine on day 14 ultrafiltration, clinical symptoms and serum CRP normalized within 3 days. In conclusion, Neisseria sicca should be considered as a rare cause of PD peritonitis. Our case report further illustrates the importance of ultrafiltration failure as an early and main symptom of peritoneal inflammation. The frequently used peritonitis criteria may not apply to cases of mild PD peritonitis.

C-Reactive Protein↗

Association of two MTHFR polymorphisms with total homocysteine plasma levels in dialysis patients.

The effect of the combined 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T and 1298A-->C genotype on total homocysteine (tHcy), folate, and vitamin B(12) plasma levels was investigated in 983 subjects, including 415 hemodialysis patients, 179 peritoneal dialysis patients, and 389 healthy individuals. Mean tHcy plasma concentrations were 27.2 +/- 15.8 micromol/L in hemodialysis patients, 25.4 +/- 19.1 micromol/L in peritoneal dialysis patients, and 8.9 +/- 3.5 micromol/L in healthy individuals. Hyperhomocysteinemia (tHcy > 15 micromol/L) was detected in 81.6% of patients and 2.6% of controls. Multiple stepwise regression analysis showed that the MTHFR 677C-->T/1298A-->C genotype (CC/AA, CC/AC, CC/CC, CT/AA, CT/AC, TT/AA), vitamin use, age, folate and vitamin B(12) plasma level were significant predictors of tHcy plasma levels. Analysis of variance showed that this effect of MTHFR genotypes on tHcy level was caused by significantly greater tHcy levels in 677TT/1298AA hemodialysis and peritoneal dialysis patients versus other genotypes. Compound heterozygous controls (677CT/1298AC genotype) had significantly greater tHcy levels compared with 677CC/1298AA controls. There was no major effect of MTHFR polymorphisms on folate and vitamin B(12) plasma concentrations. This study shows that the MTHFR 677TT/1298AA genotype, but not the 677CT/1298AC genotype, is a significant predictor of tHcy plasma levels in dialysis patients.

Adult↗

A preceding exchange with polyglucose versus glucose solution modifies peritoneal equilibration test results.

The peritoneal equilibration test (PET) is an important tool for evaluating peritoneal membrane characteristics. The polyglucose icodextrin induces ultrafiltration caused by colloid osmosis through the small pores of the peritoneal membrane and therefore is especially effective during long dwell times. The main indications for polyglucose solutions are daytime dwells in patients on automated peritoneal dialysis and nighttime exchanges in continuous ambulatory peritoneal dialysis (CAPD) patients. In CAPD patients, PET is started immediately after the icodextrin exchange. Therefore, we performed two PETs in each of 15 CAPD patients. PET post-1.36% glucose was performed immediately after a preceding exchange with 2 L of 1.36% glucose dialysate solution (dwell time, 10 hours). PET postpolyglucose was started immediately after a preceding exchange with 2 L of 7.5% icodextrin solution (dwell time, 10 hours). The dialysate to plasma (D/P) ratio of creatinine, phosphate, and sodium during PET postpolyglucose was significantly greater than during PET post-1.36% glucose at 1, 2, 3, and 4 hours of dwell time. The quotient of dialysate glucose at 1, 2, and 4 hours of dwell time to dialysate glucose at 0 dwell time was significantly lower in PET postpolyglucose compared with PET post-1.36% glucose. In the case of creatinine, phosphate, and glucose, PET postpolyglucose curves tended to be steeper than those of PET post-1.36% glucose during the first hour of dwell time, whereas both curves were parallel between 1 and 4 hours of dwell time. The course of D/P ratio curves of urea nitrogen, protein, and albumin was nearly identical between PET postpolyglucose and PET post-1.36% glucose. In a subgroup of 5 patients, D/P ratios of creatinine and phosphate were also greater in PET postpolyglucose compared with PET performed after a long dwell with 2.27% glucose solution. Before a scheduled PET, CAPD patients using icodextrin solution during the nighttime should perform their nighttime exchange with conventional glucose solution.

Adult↗

Increased prevalence of combined MTR and MTHFR genotypes among individuals with severely elevated total homocysteine plasma levels.

The prevalence of the methionine synthase (MTR) 2756A-->G polymorphism among individuals with severely elevated total homocysteine (tHcy) plasma levels is unknown. Therefore, 1,716 subjects, including 415 hemodialysis patients, 179 peritoneal dialysis patients, 733 kidney graft recipients, and 389 healthy subjects, were investigated. The distribution of MTR 2756A-->G, as well as 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T/1298A-->C, genotypes among study participants with extremely high tHcy plasma levels (>90th percentile) was compared with the genotype distribution of subjects with very low tHcy plasma levels (<10th percentile). The prevalence of MTR 2756AG and GG genotypes alone did not differ between individuals with extremely high or extremely low tHcy levels (P = 0.7402; odds ratio [OR], 1.076; 95% confidence interval [CI], 0.697 to 1.662). Conversely, combined MTR and MTHFR genotypes (MTR 2756AG and 2756GG and MTHFR 677TT/1298AA and 677CT/1298AC) were found more often in the highest (n = 34) compared with the lowest plasma tHcy decile (n = 19; P = 0.0252; OR, 1.983; 95% CI, 1.079 to 3.643). The number of patients with the wild-type MTR and MTHFR genotype was three times greater in the lowest compared with the highest decile (17 versus 6 patients, respectively; P = 0.0155; OR, 0.330; 95% CI, 0.126 to 0.861). In summary, our study shows that the 2756A-->G transition of MTR in combination with MTHFR 677TT/1298AA and 677CT/1298AC can be associated with extremely high tHcy plasma levels.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗

Complications of continuous ambulatory peritoneal dialysis: findings on MR peritoneography.

OBJECTIVE: The purpose of this study was to assess the diagnostic value of MR peritoneography in complications of continuous ambulatory peritoneal dialysis. SUBJECTS AND METHODS: Twenty consecutive patients treated with continuous ambulatory peritoneal dialysis who were clinically suspected of dialysis-related complications were prospectively studied with MR peritoneography. For MR peritoneography, 20 ml of gadodiamide was added to 2000-ml dialysate solution (1.36% glucose) that was instilled into the peritoneal cavity. MR peritoneography was performed with the peritoneal cavity filled (n = 12) and after complete drainage of the contrast material-dialysate mixture (n = 20) on a 1.5-T MR unit with a phased array coil. Imaging included axial T1-weighted fast low-angle shot (TR/TE, 174/4.2) with and without fat saturation and axial and coronal T2-weighted fat-saturated turbo spin-echo (3000/138) sequences. All studies were performed without IV contrast material. Images were reviewed for evidence of peritoneal leaks, hernias, loculated fluid collections, and adhesions. RESULTS: Abnormal findings were detected in 13 (65%) of 20 patients and included retroperitoneal leaks (n = 6), diaphragmatic leaks (n = 2), catheter exit-site leaks (n = 2), inguinal hernias (n = 2), and peritoneal adhesions (n = 1). CONCLUSION: MR peritoneography is useful for the evaluation of complications related to continuous ambulatory peritoneal dialysis, and it offers excellent tissue contrast and multiplanar imaging for assessment of complications.

Adolescent↗

Ultrasonography of the catheter tunnel in peritoneal dialysis patients: what are the indications?

The importance of sonography for the early detection and follow-up of tunnel infections in peritoneal dialysis patients is well documented, whereas other indications are less clear. We investigated indications and outcome of 738 ultrasound examinations of the peritoneal dialysis catheter tunnel. Indications for tunnel sonography included routine screening (27%), exit-site infection without peritonitis (24.1%), follow-up of tunnel infection (29.5%), clarification of questionable results (7.5%), pain in the course of the catheter tunnel (1.8%), peritonitis without (5.3%) and with (2.0%) exit-site infection, search for foci (2.2%), and recurrent peritonitis (0.7%). No positive sonographic results were obtained during routine screening or in patients with fever or elevated C-reactive protein levels showing no clinical signs of exit-site infection. Sonographic examinations were positive in 1 of 13 patients with pain in the course of the catheter tunnel, in 1 of 39 cases of peritonitis not associated with exit-site infection, in 12 of 15 patients with peritonitis and simultaneous exit-site infection, and in 2 of 5 patients with recurrent peritonitis. Questionable results were detected in 15 of 178 patients with exit-site infection, in 15 of 199 routine examinations, in 2 of 16 examinations of patients with elevated C-reactive protein levels or fever, and in 2 of 15 cases of peritonitis and simultaneous exit-site infection. All but two of these questionable results had to be rated as negative during further follow-up. We conclude that tunnel sonography is indicated in patients with exit-site infection (including cases with simultaneous peritonitis), for follow-up of tunnel infections, and for estimating the prognosis of these infections. Furthermore, tunnel sonography should be performed in patients with recurrent peritonitis. Tunnel sonography is not indicated for routine screening, search for foci, in cases of peritonitis without exit-site infection, or in patients with pain in the course of the catheter tunnel showing no other clinical signs of exit-site infection.

C-Reactive Protein↗

Tidal peritoneal dialysis for home-treated patients: should it be preferred?

Tidal peritoneal dialysis (TPD) was introduced to increase the efficacy of peritoneal dialysis. We measured peritoneal clearances of small solutes and beta2-microglobulin, peritoneal protein loss, and efficacy of ultrafiltration in 30 patients during TPD and intermittent peritoneal dialysis (IPD) with low-dialysate flow (1.7 L/h) and, in addition, in 17 of these patients using a high-dialysate flow (3 L/h). Using a low-dialysate flow, patients with low/low average peritoneal transport rates showed significantly better peritoneal creatinine and urea nitrogen clearances during IPD compared with TPD, whereas there was no difference between these two treatment modalities in high/high average transporters. With high-dialysate flow, peritoneal clearances of creatinine and urea nitrogen were similar between TPD and IPD independent of peritoneal transport type. Clearances of phosphate and beta2-microglobulin were similar between TPD and IPD independent of dialysate flow or peritoneal transport type. Increasing the dialysate flow rate led to a significant increase in small-solute clearances, but not beta2-microglobulin clearances, in both peritoneal transport types. Total peritoneal protein and albumin losses were similar between TPD and IPD only with low-dialysate flow. However, using a high-dialysate flow, total protein losses tended to increase in both transport types during IPD compared with TPD. In conclusion, up to a dialysate flow of 3 L/h, TPD did not provide better small-solute or middle-molecule clearances compared with IPD. Moreover, using a low-dialysate flow, IPD was superior to TPD in low/low average transporters.

Adult↗

Influence of the preceding exchange on peritoneal equilibration test results: a prospective study.

The standard peritoneal equilibration test (PET) should be performed after a long overnight dwell, which is easily possible in continuous ambulatory peritoneal dialysis patients. However, for such a procedure, patients undergoing automated peritoneal dialysis or daily ambulatory peritoneal dialysis have to change their regimen and, in the case of high peritoneal transport rates, run the risk for fluid absorption. We compared dialysate to plasma ratios (D/P) of creatinine, blood urea nitrogen (BUN), phosphate, sodium, total protein, and albumin measured during PET after an 8- to 11-hour dry period (PET dry), after a preceding exchange with a long dwell time (PET standard), and immediately after tidal peritoneal dialysis (PET tidal). D/P ratios of creatinine, BUN, phosphate, and sodium at 2 and 4 hours were greater during PET dry compared with both PET standard and PET tidal. The quotient of dialysate glucose at 2 hours to dialysate glucose at time point 0 was significantly less in PET dry compared with both PET tidal and PET standard. During the first 2 hours of PET, the increase of D/P curves of creatinine and BUN, as well as phosphate, was significantly steeper in PET dry than PET tidal and PET standard. D/P ratios of albumin and protein were greatest in PET dry and least in PET tidal. There was a significant difference between all three PETs at 0, 2, and 4 hours of dwell time. PET curves were significantly steeper during PET dry compared with PET tidal in case of D/P protein (during the first 2 hours of dwell time) and D/P albumin (during the entire dwell time). Similar differences between the PET curves of protein and albumin were observed between PET dry and PET standard. These data clearly indicate a dry period before PET significantly influences the D/P ratios of small solutes, protein, and albumin measured during the test.

Adult↗

Peritoneal elimination of homocysteine moieties in continuous ambulatory peritoneal dialysis patients.

BACKGROUND: The amount of total homocysteine eliminated by peritoneal dialysis and its relationship to peritoneal transport characteristics in continuous ambulatory peritoneal dialysis (CAPD) patients are unknown. METHODS: The influence of total homocysteine, folate, and vitamin B12 plasma concentrations, serum albumin levels, age, sex, dialysate to plasma ratio (D/P) creatinine, D/D0 glucose, D/P albumin, dialysate effluent volume, and effluent albumin on the daily peritoneal excretion of total homocysteine was investigated in 39 CAPD patients. The relationship of D/P creatinine to D/P total homocysteine, D/P free homocysteine, and D/P protein-bound homocysteine was analyzed additionally in a subgroup of 25 patients. RESULTS: We observed a significant influence of plasma total homocysteine concentrations (P = 0.0001) of the daily dialysate effluent volume (P = 0.0221) and of the D/P creatinine (P = 0.0132) on peritoneal elimination of total homocysteine. The daily peritoneal excretion of total homocysteine was 38.94 +/- 20.82 mumol (5.27 +/- 2.81 mg). There was a positive linear association of the daily total homocysteine elimination with plasma total homocysteine concentrations (P = 0.0001). A significant linear correlation was observed between D/P creatinine and D/P total homocysteine (P = 0.0001), D/P free homocysteine (P = 0.0001), as well as D/P protein-bound homocysteine (P = 0.0001). CONCLUSIONS: The peritoneal elimination of total homocysteine primarily depends on the plasma total homocysteine concentration. Elevated total homocysteine plasma levels cannot be reduced efficiently by peritoneal dialysis.

Adult↗

Iron status and iron supplementation in peritoneal dialysis patients.

Iron deficiency represents an important problem in peritoneal dialysis patients, especially during erythropoietin therapy. A combination of serum ferritin, transferrin saturation, and/or the percentage of hypochromic red cells should be used to assess iron status in peritoneal dialysis patients. Primarily, oral iron supplementation should be the preferred therapy. However, most of the studies using oral substitution in erythropoietin-treated peritoneal dialysis patients show a progressive decline of serum ferritin. Therefore, parenteral iron supplementation is required in part of the patients, and the intravenous route should be preferred in these cases. Intravenous iron therapy is recommended if serum ferritin falls below 100 microg/liter and should be stopped if the serum ferritin level is more than 650 microg/liter. The optimal form of intravenous iron supplementation is still unclear. Injections once to three times per week restrict the patients' flexibility, but application of higher doses in longer intervals may lead to an impairment of neutrophil functions, probably connected to a higher risk of infection. We treated 17 stable peritoneal dialysis patients with 100 or 200 mg iron saccharate monthly over a period of six months and found an increase of transferrin saturation (from 12.1+/-1.6 to 20.9+/-2.4%, P = 0.026), serum ferritin (from 100.4+/-32.0 to 372.4+/-54.6 microg/liter, NS) and hematocrit (from 32.0+/-0.8% to 35.1+/-0.9%, P = 0.099). The required erythropoietin dosage could be reduced significantly (from 148.4+/-30.3 to 69.4+/-19.5 U/kg/week, P = 0.025). Side effects occurred in 0.9% after application of 100 mg and in 5.9% after injection of 200 mg iron saccharate. The incidence of catheter infections and peritonitis was the same in the period before and after the start of treatment. Further studies are needed to find the most suitable regime of iron supplementation for peritoneal dialysis patients.

Administration, Oral↗

Major determinants of hyperhomocysteinemia in peritoneal dialysis patients.

The mechanisms leading to elevated total homocysteine concentrations in peritoneal dialysis patients are only partially understood. We show that a common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene (C677T transition) results in increased total homocysteine levels in peritoneal dialysis patients compared to age- and sex-matched healthy individuals. The allelic frequency of the C677T transition in the MTHFR gene in peritoneal dialysis patients (0.29) was comparable to the frequency in healthy individuals (0.34). Separate comparison of the total homocysteine plasma levels between non-carriers of the MTHFR polymorphism (C/C), heterozygous (C/T) and homozygous (T/T) subjects was performed by analysis of covariance in the patient and the control group. In the patient group the mean total homocysteine level was 61.7 +/- 40.1 mumol/liter in individuals with the (T/T) genotype, which was significantly higher than the total homocysteine concentration of 23.1 +/- 15.8 mumol/liter in (C/T) patients and 22.2 +/- 11.1 mumol/liter for non-carriers (P = 0.0001). Vitamin B12 (P = 0.0001), folate (P = 0.0005), serum creatinine (P = 0.016), albumin (P = 0.0157) and dialysis center (P = 0.0173) significantly influenced total homocysteine plasma levels in peritoneal dialysis patients, whereas this was not the case for age, gender, weekly Kt/V, weekly creatinine clearance, residual renal function, duration of dialysis, mode of peritoneal dialysis and vitamin intake. Folate levels in peritoneal dialysis patients were significantly affected by the MTHFR genotype (P = 0.016). Elevated total homocysteine levels in diabetic patients with cardiovascular disease were associated with increased cardiovascular morbidity. In summary, the present study provides evidence that homozygosity for the C677T transition in the MTHFR gene, low vitamin B12 and low folate levels result in elevated total homocysteine levels in peritoneal dialysis patients.

5,10-Methylenetetrahydrofolate Reductase (FADH2)↗

Adrenal function in patients with chronic renal failure.

Previous studies have reported divergent findings on the function of the hypothalamic-pituitary-adrenal axis in patients with chronic renal failure (CRF). The low-dose adrenocorticotropin (ACTH) test offers the possibility of unmasking adrenal dysfunction, which might remain undiscovered using the ACTH test with the standard 250-microg dose. Furthermore, the choice of renal replacement therapy (either hemodialysis or continuous ambulatory peritoneal dialysis [CAPD]) might have an impact on adrenal function. To investigate these possibilities, ACTH tests were performed with three different doses (ie, 1, 5, and 250 microg) in 14 CRF patients and in seven healthy controls. Seven of the CRF patients were receiving chronic hemodialysis and seven were receiving CAPD. Basal plasma concentrations of cortisol were comparable in the three groups tested (5.3+/-0.4 microg/dL in the controls, 6.6+/-0.7 microg/dL in the hemodialysis patients, and 7.9+/-1.0 microg/dL in the CAPD patients), whereas basal ACTH concentrations were significantly elevated in the CRF patients (28.5+/-3.8 pg/mL in the hemodialysis patients and 33.0+/-6.0 pg/mL in the CAPD patients) when compared with normal controls (17.0+/-1.4 pg/mL; P < 0.05). All three doses of ACTH resulted in a rapid increase of plasma cortisol concentrations that was comparable in all three groups. In the hemodialysis patients, a trend toward a diminished response to the lowest dose of 1 microg was noticed. We conclude, therefore, that adrenal response to ACTH in various doses is unaffected in CRF independent of whether hemodialysis or CAPD is chosen for renal replacement therapy.

Adrenal Glands↗

New criteria for management of catheter infections in peritoneal dialysis patients using ultrasonography.

Catheter-related infection is one of the most important causes of technical dropout in peritoneal dialysis patients. Both the type of cultured organism and the extent of inflammation are well known prognostic factors for the outcome of these infections. From December 1994 to November 1996, 96 catheter-related infections without simultaneous peritonitis occurred in 49 of 86 peritoneal dialysis patients treated in this study. During the observation period, only single-cuff catheters were used. Staphylococcus aureus was the most common organism cultured (51%). Involvement of the tunnel was diagnosed by sonography in 57.1% of all Staphylococcus aureus cases, but only in 26.1% of Staphylococcus epidermidis-related exit-site infections. Ten of the 96 catheter-related infections (10.4%) resulted in catheter loss. Catheter removal was necessary only in cases of deep tunnel infection caused by Staphylococcus aureus. The number of gram-negative catheter infections was too small to allow conclusive analysis. Although sonography of the catheter tunnel is now well established in the early diagnosis of tunnel infections, no clear guidelines exist for management of these infections. In this study, patients with deep tunnel infection who did not require catheter removal showed a significant decline of the hypoechogenic area around the cuff (from 7.02 +/- 0.70 to 3.75 +/- 1.04 mm, P < 0.002) 2 wk after initiation of therapy. No significant decline was observed in patients who later lost their catheters. On the basis of these data, it is concluded that in cases of exit-site and superficial tunnel infection, conservative treatment should be performed. In cases of deep tunnel infection without peritonitis caused by Staphylococcus aureus, antibiotic treatment should be started and sonographic examination should be performed every second week. If the hypoechogenic area around the cuff decreases (> 30%), conservative treatment should be prolonged. In cases without sonographic improvement (< 30%) 2 wk after therapy, catheter removal is recommended.

Abdominal Abscess↗

New strategies to prevent Staphylococcus aureus infections in peritoneal dialysis patients.

The importance of Staphylococcus aureus as etiological agent for catheter-related infections and peritonitis in peritoneal dialysis patients is well established. To evaluate groups at risk of developing Staphylococcus aureus infections, nasal and exit-site cultures were performed in 76 peritoneal dialysis patients monthly over a period of 3 yr. The risk of Staphylococcus aureus catheter infection was significantly higher in diabetic (group 1) and immunosuppressed (group 2) patients compared with nondiabetic and nonimmunosuppressed (group 3) patients. In diabetic patients, Staphylococcus aureus-positive nasal cultures were more frequent than positive cultures taken from the bland exit-site (73.3% versus 60.0%). On the other hand, both positive and negative exit-site cultures had a better prognostic value for Staphylococcus aureus catheter infection compared with nasal cultures. In immunosuppressed patients, both nasal and exit-site carriages were associated with a very high risk of Staphylococcus aureus catheter infection, but nasal swabs were far more often positive than swabs from the bland exit-site (72.7% versus 25.0%). However, the risk of infection was also high for non-nasal and non-exit-site carriers in this group. In nondiabetic and nonimmunosuppressed patients, the risk of Staphylococcus aureus catheter infection was increased only if two or more positive nasal cultures were detected. It is concluded that in diabetic patients, antibiotic prophylaxis should be performed in all Staphylococcus aureus exit-site carriers. All immunosuppressed patients should be treated prophylactically. In contrast, in nondiabetic and nonimmunosuppressed patients, prophylactic treatment should be considered only in nasal carriers with two or more positive cultures. The overall low peritonitis rate does not influence this prevention strategy.

Adult↗