Search PubMed⌕ Search

Biomedical subjects

J Bernardini

Publications and source records attributed to J Bernardini.

At least 55 records · Page 3Linked to original sources
PubMed1993

Staphylococcus aureus peritonitis is associated with Staphylococcus aureus nasal carriage in peritoneal dialysis patients.

Although the definition of S. aureus nasal carriage in peritoneal dialysis patients is variable, carriage is often defined as 2 or more positive cultures for S. aureus. We investigated the relationship between S. aureus infections and nasal carriage (defined as 1 or more positive nose cultures) in 138 patients on peritoneal dialysis. By this definition, approximately 50% of the patients were carriers. The rates of S. aureus exit-site infection (0.28/year vs 0.43/year, p < 0.001) and peritonitis (0.08/year vs 0.20/year, p < 0.001) were lower in the noncarriers (patients with no positive nose cultures) than in those patients who had 1 or more positive nose cultures. Patients with only 1 positive nose culture had a similar S. aureus exit-site infection rate (0.31/year vs 0.28/year), but a higher peritonitis rate (0.24/year vs 0.08/year, p < 0.001) compared to those patients with no positive nose cultures. However, patients with 2 or more positive nose cultures were at increased risk for both S. aureus exit-site infections and peritonitis. This relationship held even when only patients with frequent nose cultures were included in the analysis. Thus patients with even 1 positive nose culture for S. aureus are at risk for S. aureus peritonitis and should not be classified as noncarriers.

Carrier State↗
PubMed1993

A comparison of peritoneal dialysis-related infections in black and white patients.

OBJECTIVE: To determine if black patients in our peritoneal dialysis (PD) program had higher rates of PD-related infections. The outcomes of black patients versus white patients were also reviewed. DESIGN: A review of prospectively collected patient demographic and PD-related infection data and outcomes, from 1979 to 1991. PATIENTS: The 68 black patients in our PD program were matched with white control patients for age, sex, insulin dependence, time on dialysis, and mode of dialysis (CAPD or CCPD). The infection, demographic, and outcome data from the two groups were compared. RESULTS: Black patients had higher peritonitis rates (1.10 vs 0.82 episodes/year, p = 0.001) and exit-site infection rates (1.13 vs 0.95 episodes/year, p = 0.02) than the white control patients. Tunnel infection rates were 0.21 episodes/year in both groups. S. epidermidis peritonitis was more common in black patients (48% of episodes vs 21% of episodes in whites, p = 0.005), and S. aureus peritonitis was more common in white patients (29% vs 11% in blacks, p = 0.005). The subset of black patients (n = 13) on a disconnect system (Y-set) had a peritonitis rate similar to their white controls on the Y-set (0.41 vs 0.74 episodes/year, p = 0.27). There were no episodes of S. epidermidis peritonitis in this subset of black patients. Black patients had fewer S. aureus exit-site infections than white patients (21% vs 41%, p = 0.005). Peritonitis was the leading cause of transfer to hemodialysis in the black patients but not in the white patients. CONCLUSION: The susceptibility to S. aureus and S. epidermidis infections differs in black and white patients on peritoneal dialysis for unclear reasons. Peritonitis rates in black patients can be reduced to that of white patients if a disconnect system is used.

Black People↗
PubMed1992

Polymicrobial peritonitis in patients on continuous peritoneal dialysis.

Little data are available about the characteristics, outcome, and risk factors for polymicrobial peritonitis in patients on continuous peritoneal dialysis. We therefore reviewed the 43 episodes of polymicrobial peritonitis that occurred in 39 of our patients over the 11.5 years of our program. Polymicrobial peritonitis represented 9% (43/492) of all peritonitis episodes. Only three episodes of polymicrobial peritonitis were associated with an enteric source. Sixteen percent (7/43) of the polymicrobial peritonitis episodes were associated with catheter infections. Staphylococcus aureus was one of the cultured organisms in 33% of the polymicrobial peritonitis episodes. Patients with polymicrobial peritonitis had higher rates of tunnel infection (0.28/yr v 0.18/yr) and overall peritonitis (1.23/yr v 0.81/yr) than patients with single-organism peritonitis. Black patients were more likely to have polymicrobial peritonitis (12/56 v 27/338 whites, chi 2 = 9.8, P less than 0.005). Patient age, gender, time on peritoneal dialysis, insulin dependence, and cause of end-stage renal disease had no influence on polymicrobial peritonitis. Significantly more catheters were removed for polymicrobial peritonitis than for single-organism peritonitis (17/42 v 89/420, chi 2 = 7.05, P less than 0.01), but in 60% of the episodes, the polymicrobial peritonitis was successfully treated without catheter removal. Polymicrobial peritonitis often occurs without gram-negative organisms and extension of catheter infection may be involved in some cases. For unclear reasons, black patients are at higher risk of polymicrobial peritonitis.

Bacteria↗
PubMed1992

Calcium mass transfer with dialysate containing 1.25 and 1.75 mmol/L calcium in peritoneal dialysis patients.

Studies with 1.75 mmol/L calcium dialysate have shown that patients gain calcium from dialysate. Thus, hypercalcemia, especially when calcium compounds are used for phosphate control, is a commonly seen complication. Dialysate with 1.25 mmol/L calcium has been available since 1989. Little is known about calcium mass transfer (CMT) with dialysate of this calcium concentration. CMT was measured in 20 stable adult peritoneal dialysis patients. Each CMT study consisted of a 2-L continuous ambulatory peritoneal dialysis (CAPD) exchange with a dwell time of 4 hours. CMT studies were performed using 1.25 and 1.75 mmol/L calcium dialysate with 1.5, 2.5, and 4.25 g/dL dextrose concentrations. CMT with 1.25 mmol/L calcium dialysate was compared to that with 1.75 mmol/L for each dextrose concentration. With a dextrose concentration of 1.5 g/dL, the mean CMT for 1.25 mmol/L calcium dialysate was -0.1 +/- 0.3 mmol versus 0.6 +/- 0.3 mmol for 1.75 mmol/L calcium dialysate (P < 0.0001). A dextrose concentration of 2.5 g/dL resulted in a mean CMT of -0.4 +/- 0.2 mmol for 1.25 mmol/L calcium versus 0.45 +/- 0.25 mmol for 1.75 mmol/L calcium (P < 0.0001). Using a dextrose concentration of 4.25 g/dL, the mean CMT was -0.7 +/- 0.25 mmol for 1.25 mmol/L calcium versus -0.05 +/- 0.35 mmol for 1.75 mmol/L calcium (P < 0.0001). Mean serum ionized calcium (SiCa) was between 1.15 and 1.20 mmol/L for all study groups. CMT inversely correlated with SiCa for each type of dialysate used. CMT was dependent on the concentrations of calcium and dextrose in the dialysate and the SiCa level at the time of the exchange.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Increased risk of Staphylococcus epidermidis peritonitis in patients on dialysate containing 1.25 mmol/L calcium.

Peritoneal macrophage function is decreased in vitro in the presence of dialysate with 1.25 mmol/L calcium compared with that containing 1.75 mmol/L calcium. Theoretically, patients using this dialysate may have a higher risk of peritonitis. Nineteen patients on continuous ambulatory peritoneal dialysis (CAPD) or continuous cycling peritoneal dialysis (CCPD) were converted from dialysate with 1.75 mmol/L calcium (mean time, 33 +/- 26 months) to that with 1.25 mmol/L calcium, for some or all exchanges (mean time, 10 +/- 4.7 months). Peritonitis rates were compared with 19 control patients who remained on dialysate with 1.75 mmol/L calcium. The two groups were matched for the proportion of diabetics, sex, age, use of the Y-set, and dialysis modality (CAPD, CCPD). Peritonitis rates were similar in the study patients before conversion to 1.25 mmol/L calcium dialysate and in the control patients (0.49 v 0.58 episodes/patient-year, respectively). After conversion to dialysate with 1.25 mmol/L calcium, the peritonitis rate was 0.82 episodes/patient-year contrasted to 0.58 episodes/patient-year in the control patients (P = 0.09). The peritonitis rate due to Staphylococcus epidermidis was 0.51 episodes/patient-year when 1.25 mmol/L calcium dialysate was used, and 0.19 episodes/patient-year for the comparable period in the control patients on 1.75 mmol/L calcium dialysate (P = 0.005). The proportion of peritonitis episodes due to S epidermidis increased from 20% to 61% after conversion to 1.25 mmol/L calcium (P = 0.01). The increased risk of peritonitis due to S epidermidis in patients using dialysate with 1.25 mmol/L calcium is consistent with a previous study demonstrating that clearance of S epidermidis by peritoneal macrophages is less effective with a decrease in the dialysate calcium content.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Hemoperitoneum complicating chronic peritoneal dialysis: single-center experience and literature review.

Hemoperitoneum is a well-recognized, if uncommon, complication of chronic peritoneal dialysis. In this review of 424 patients maintained on peritoneal dialysis at a single center during an 11-year period, 26 patients (6.1%) developed one or more episodes of hemoperitoneum. Three patients had hemoperitoneum on two separate occasions with different etiologies. One additional patient was seen on a hospital consultative service. Three types of bleeding episodes were observed. Twenty-one of 30 (70%) were benign, consisting of pink-tinged dialysate with little clinical consequence (group 1). Three (10%) consisted of minor hemoperitoneum associated with significant intra-abdominal pathology (group 2), and six (20%) required active intervention (group 3). The most frequent cause of hemoperitoneum was bleeding related to menstruation or ovulation; hemoperitoneum was more common in women than in men. Two patients had hemoperitoneum occurring after more than 6 years on dialysis. In both, the etiology was sclerosing peritonitis, an association not previously noted. The less common etiologies of hemoperitoneum encountered in our patients were similar to those in reports from other centers and are compiled here.

Female↗
PubMed1992

Erythema: does it indicate infection in a peritoneal catheter exit site?

The definition of a peritoneal catheter exit site infection varies from one dialysis center to another. A review of abnormal appearing exit sites (n = 334 in 169 patients) from 1/83 to 3/91 was done to compare outcome in exit sites presenting with erythema (39, 12%) to those with drainage plus erythema (72, 22%) or drainage alone (223, 67%). Resolution of the abnormality occurred in 48% of those exit sites with drainage, 62% with erythema and drainage, and 79% with erythema alone (p < 0.005). S. aureus was present in 62% of the cultured exit sites which had erythema alone, 64% with erythema plus drainage, and 41% with drainage alone, while Gram negative rods were present in 13%, 12%, and 35%, respectively (p < 0.005). Twenty-three of the 39 exit sites with erythema were not initially treated with antibiotics; 87% resolved compared with 69% of those treated immediately with antibiotics (p = ns). Seven of the 8 erythematous exit sites that did not resolve progressed to tunnel infection and/or peritonitis and required catheter removal, despite the addition of antibiotics in the three initially untreated. Six of the 8 unresolved erythematous exit sites were due to S. aureus. These results indicate that, although drainage is the commonest exit site abnormality and has the worst prognosis, peri-catheter erythema is not always benign, representing an early sign of infection in some cases.

Catheterization↗
PubMed1992

Calcium mass transfer in peritoneal dialysis patients using 2.5 mEq/l calcium dialysate.

Standard peritoneal dialysate has a relatively high calcium concentration of 3.5 mEq/l. Peritoneal dialysis patients thus gain calcium from the dialysate which contributes to the risk of hypercalcemia. Dialysate with 2.5 mEq/l calcium is now available. Theoretically, using dialysate with this calcium content, calcium transfer should be negative (from the patient into the dialysate) when the patient is hypercalcemic, and positive when the patient is normocalcemic or hypercalcemic. Thus, 2.5 mEq/l calcium dialysate may allow larger doses of calcium carbonate to be prescribed. We compared calcium mass transfer (CMT) in 17 stable peritoneal dialysis patients using 3.5 and 2.5 mEq/l calcium dialysate. A solution of 2.05 l, 1.5 g/dl dextrose was dwelled for 4 hours. Calcium was measured in the drained dialysate and serum (total and ionized). Mean CMT was 0.7 +/- 0.5 mEq/exchange using 3.5 mEq/l calcium dialysate and -0.9 +/- 0.9 mEq/exchange using 2.5 mEq/l calcium dialysate (p less than 0.0001). At the time of the CMT studies, the mean serum ionized calcium levels were identical for the two groups (2.6 mEq/l). CMT correlated inversely with serum total calcium, serum ionized calcium, and drained dialysate volume. During hypercalcemia calcium transfer was from the dialysate to the patient when 3.5 mEq/l calcium dialysate was used, but from the patient to the dialysate when 2.5 mEq/l calcium dialysate was used. We conclude that 2.5 mEq/l calcium dialysate is effective in removing calcium and will be helpful in preventing hypercalcemia when large doses of oral calcium compounds are prescribed as a phosphate binder.

Adult↗
PubMed1991

Risk factors for tunnel infections in continuous peritoneal dialysis.

Little data are available about risk factors for peritoneal catheter subcutaneous tunnel infection. Therefore, we analyzed tunnel infections occurring in our program over a 10.5-year period. One hundred twenty-nine tunnel infections occurred in 92 of 411 patients (22%) on peritoneal dialysis for a mean of 19 +/- 19 months. Tunnel infection rate was 0.19 per year. By 1 year, 15% of patients had a tunnel infection, and by 2 years, 23%. Tunnel infection rates decreased with increasing time on peritoneal dialysis: 2.4 per year for patients on peritoneal dialysis less than 1 year, 0.8 per year for patients on dialysis 1 to 2 years, and 0.4 per year for patients on dialysis greater than 2 years (all different at P less than 0.01). Organisms were cultured in 109 tunnel infections: gram-positive cocci in 77 episodes (71%) [Staphylococcus aureus 57, 52%], and gram-negative bacilli in 24 episodes (22%). Tunnel infection rates were higher in diabetics than in nondiabetics (0.27 per year v 0.16 per year, respectively; P less than 0.001 by life-table analysis of time to first infection) and also higher in women than in men (0.23 per year v 0.17 per year, P less than 0.001). Tunnel infection rates were 0.35 per year for diabetic women, 0.20 per year for diabetic men, 0.18 per year for nondiabetic women, and 0.15 per year for nondiabetic men (groups different, P less than 0.001). Race and age were similar in patients with and without tunnel infections. Catheter loss was 80% when tunnel infection was associated with peritonitis and 40% when tunnel infection alone was present (P less than 0.001). We conclude that the risk of tunnel infection is highest early in the course of peritoneal dialysis and that diabetic women, for unclear reasons, are at the highest risk.

Adult↗
PubMed1991

Catheter infections in insulin-dependent diabetics on continuous ambulatory peritoneal dialysis.

We compared a group of 60 insulin-dependent diabetics maintained on CAPD with 60 nondiabetic matched controls to determine if the diabetic patients were at increased risk for catheter-related infections. Although catheter infection rates were 17% higher in the diabetics (1.4/year versus 1.2/year in nondiabetics), time to first catheter infection was not different between the groups (p = 0.6). Rates of peritonitis, peritonitis associated with catheter infection, multiple catheter infection, and catheter removal were also similar among the diabetics and controls. S. aureus caused 52% (42/81) of the catheter infections in the diabetics and 60% (35/58) in the controls. More catheter infections in the nondiabetics versus the diabetics lacked drainage or resulted in sterile cultures (17/75 versus 7/88 respectively, p less than or equal to 0.01), but the significance of this finding is uncertain. In conclusion, we did not find insulin-dependent diabetes mellitus to be a statistically significant risk factor for catheter-related infections.

Bacterial Infections↗
PubMed1991

Vestibular toxicity due to gentamicin in peritoneal dialysis patients.

Gentamicin is well known to be a cause of vestibular toxicity. Despite this, gentamicin is often used to treat peritonitis and exit-site infections in peritoneal dialysis patients because of the ease of intraperitoneal administration and the broad coverage of aerobic Gram-negative bacilli, including Pseudomonas aeruginosa. We report 4 cases of severe vestibular toxicity occurring in peritoneal dialysis patients treated with gentamicin. They were all treated as outpatients for peritonitis or an exit-site infection while on continuous ambulatory peritoneal dialysis (CAPD) or continuous cyclic peritoneal dialysis (CCPD). The drug was administered to 3 patients in each peritoneal exchange (5 mg/L) after a loading dose. A fourth patient was given 1 mg/kg of intraperitoneal gentamicin every other day. The mean length of treatment was 21 days. Levels were not used to adjust the doses. All developed severe vertigo from which there was incomplete or no recovery. We suggest that gentamicin and the other aminoglycosides should be used in peritoneal dialysis patients only when there is no suitable alternative antibiotic. When gentamicin is administered, levels should be carefully followed. Studies should be performed in peritoneal dialysis patients on the feasibility of dosing gentamicin intermittently, which may be less toxic than continuous intraperitoneal administration.

Adult↗
PubMed1991

An analysis of ten-year trends in infections in adults on continuous ambulatory peritoneal dialysis (CAPD).

Infectious complications are the Achilles heel of CAPD. To determine trends in these events, we analyzed the CAPD related infections of 303 adults on CAPD at a single university center between 1979 and 1989. During this decade the percentage of insulin-dependent diabetics increased from 14% to 39% (p less than 0.005). Peritonitis rates fell from 2.4 episodes/y in 1979 to 0.8 episodes/y in 1989. The proportion of patients with multiple episodes of peritonitis decreased (40% of the patients in 1979-1982 vs 15% in 1983-1989, p = 0.0001) while the proportion of patients with no episodes of peritonitis increased during the same periods (29% vs 49%, p = 0.005). The proportion of peritonitis episodes due to S. aureus rose over the 10-year period (p = 0.005), while those due to S. epidermidis decreased (p less than 0.10). The overall incidence of S. aureus peritonitis remained unchanged. Catheter infection rates initially increased and then fell during the decade; S. aureus remained the predominant cause. The proportion of peritonitis episodes associated with catheter infection rose (13% in 1982 vs 24% in 1989, p = 0.025), and in 1989, 80% of these episodes were caused by S. aureus. Catheter loss was also primarily due to S. aureus infections in 1989 (80%). Infections due to P. aeruginosa were a persistent problem. The proportion of patients transferring to hemodialysis each year paralleled catheter loss rates, which in turn appeared to be more related to catheter infection rates than to peritonitis rates. We conclude that control of S. aureus and P. aeruginosa will be the key to future reductions in the infectious complications of CAPD patients.

Catheters, Indwelling↗
PubMed1991

The effect of body weight on CAPD related infections and catheter loss.

CAPD related infections and catheter loss continue to be the major problems facing the peritoneal dialysis patient. Few risk factors for infections and catheter loss have been identified. We hypothesized that overweight and underweight patients may be at increased risk for infections and catheter related problems. We examined the effect of the patient's weight at the start of peritoneal dialysis on the subsequent peritonitis and catheter infection rates, as well as catheter loss. Weight was expressed as a percentage of ideal body weight (IBW). Those patients who were more than 110% of IBW were considered to be overweight, 90 to 110% of IBW normal and less than 90%, underweight. An equivalent percentage of patients were overweight and underweight at the initiation of peritoneal dialysis (55/228, 24% for both groups). Overweight, normal, and underweight patients had peritonitis rates of 1.0, 0.9, and 0.8 episodes/y and catheter infection rates of 1.1, 1.2, and 0.8 episodes/y, respectively. Despite these similar rates, catheter loss due to infectious complications was greatest in the overweight group and least in the underweight group (p less than 0.05). No obvious explanation for the difference in catheter loss rate was found. Neither S. aureus nor P. aeruginosa infections occurred more frequently in the overweight patients. However, S. aureus infections more often led to catheter loss in the overweight patients. Catheter loss due to catheter leaks and failure to drain was similar in the three groups of patients. We conclude that deviation from ideal body weight at the initiation of dialysis is not a risk factor for CAPD related infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Continuous cycling peritoneal dialysis is associated with lower rates of catheter infections than continuous ambulatory peritoneal dialysis.

Continuous cycling peritoneal dialysis (CCPD), unlike continuous ambulatory peritoneal dialysis (CAPD), provides freedom from daytime exchanges and is associated with lower rates of peritonitis. However, catheter infection (CI) rates have not been reported for CCPD. Previous data suggested that a CAPD disconnect system (Y-set) was associated with lower rates of CI. These results suggested that patients on CCPD, which is also a disconnect system, might also have low CI rates. We evaluated our CCPD patients for infection rates and compared them with two groups of matched control CAPD patients, one using a spike system and one a Y-set disconnect system to evaluate this hypothesis. The CCPD patients had the lowest rates of CIs (0.5 episodes per year or one episode every 25 months), followed by the CAPD patients using the Y-set (0.8 episodes per year or one episode every 14 months). CAPD patients using the spike system had the highest rates of CIs (1.2 episodes per year or one episode every 10 months). Peritonitis rates followed the same pattern among the patient groups: CCPD, 0.3 episodes per year; CAPD, Y-set 0.5 episodes per year; CAPD, spike system 1.3 episodes per year. Our data suggest that disconnect systems, such as the CAPD Y-set and CCPD, reduce CIs, as well as peritonitis.

Catheterization↗
PubMed1990

Methicillin-resistant staphylococcal infections in an outpatient peritoneal dialysis program.

In view of the increasing concern about hospital-acquired methicillin resistance, we examined the sensitivities and outcome of staphylococcal infections related to outpatient peritoneal dialysis over a 5-year period. Data on all episodes of peritonitis (n = 360) and catheter infections (n = 507) were gathered prospectively from January 1984 to December 1988. The numbers of patients on peritoneal dialysis each year ranged from 136 in 1984 to 109 in 1987. Fifteen methicillin-resistant staphylococcal infections (MRSI) related to outpatient peritoneal dialysis occurred. Three were due to methicillin-resistant Staphylococcus aureus found in infected exit sites (2.3% of all S aureus catheter infections). Two of these infections occurred in a continuous ambulatory peritoneal dialysis (CAPD) patient who carried methicillin-resistant S aureus in his nares. The other 12 methicillin-resistant organisms were coagulase-negative staphylococci that caused peritonitis. There was a significant increase in the percentage of episodes of coagulase-negative staphylococci peritonitis caused by methicillin-resistant organisms; from 5% (3/57) in 1984 through 1986 to 28% (9/32) in 1987 through 1988 (P less than 0.005). In view of the high percentage of coagulase-negative staphylococci peritonitis that is methicillin-resistant, vancomycin rather than cephalosporins should be used for initial treatment.

Humans↗
PubMed1990

The effect of the Y-set on catheter infection rates in continuous ambulatory peritoneal dialysis patients.

We hypothesized that catheter infections in continuous ambulatory peritoneal dialysis (CAPD) patients may be reduced with a disconnect system. We examined this theory in 116 CAPD patients over a 2-year period. In CAPD patients who switched to the Y-set (n = 22), the catheter infection rate decreased from one per 13 patient-months to one per 26 patient-months (P = 0.05), whereas the catheter infection rate in matched controls (n = 22) remained unchanged. Patients who began CAPD using the Y-set (n = 36) had catheter infection rates of one per 14 patient-months versus one per 8 patient-months in matched controls (n = 36, P = 0.05). Staphylococcus aureus was the most common cause of catheter infections in both groups of patients. However, Pseudomonas aeruginosa replaced Staphylococcus epidermidis as the second most common cause of catheter infections in the patients using the Y-set. The number of catheters that had to be removed due to catheter infections, mainly those due to S aureus or P aeruginosa, was the same in the Y-set and control groups. We conclude that the Y-set system is associated with reduced numbers of catheter infections, but that catheter loss from catheter infections remains a serious problem.

Adult↗