Clearing the clouds: Case-report and review of the literature

In peritoneal dialysis (PD), a cloudy dialysate is an alarming finding. Bacterial peritonitis is the most common cause, however, atypical infections and non-infectious causes must be considered. A 46-year-old man presented with asthenia, paraesthesia, foamy urine and hypertension. Laboratory testing revealed severe azotaemia, anaemia, hyperkalaemia and nephrotic-range proteinuria. Haemodialysis was started through a central venous catheter. Later, due to patient preference, a Tenckhoff catheter was inserted. Conversion to PD occurred 3 weeks later, during hospitalization for a presumed central line infection. A month later, the patient was hospitalized for neutropenic fever. He was diagnosed an acute parvovirus infection and was discharged under isoniazid for latent tuberculosis. Four months later, the patient presented with fever and a cloudy effluent. Peritoneal fluid (PF) cytology was suggestive of infectious peritonitis, but the symptoms persisted despite antibiotic therapy. Bacterial and mycological cultures were negative. No neoplastic cells were detected. Mycobacterium tuberculosis eventually grew in PF cultures, despite previous negative molecular tests. Directed therapy was then initiated with excellent response. Thus, facing a cloudy effluent, one must consider multiple aetiologies. Diagnosis of peritoneal tuberculosis is hampered by the lack of highly sensitive and specific exams. Here, diagnosis was only possible due to positive mycobacterial cultures.

Timely Initiation of Dialysis — Single-Exchange Experience in 39 Patients Starting Peritoneal Dialysis

♦ Objective

To establish the effectiveness and patient acceptability of initiating peritoneal dialysis (PD) according to published guidelines.

♦ Setting

A university teaching hospital and a neighboring district general hospital.

♦ Design

Nonrandomized prospective pilot study.

♦ Patients

39 patients with a Kt/V > 2.0 attending predialysis clinics at both hospitals agreed to participate in this study.

♦ Methods

Patients were started on a single exchange of dialysate overnight. Dialysis adequacy was monitored at least every 2 months and incremental increases in dialysis were used to maintain combined urinary and dialysis Kt/V above 2.0. Routine laboratory parameters and complications of dialysis were monitored during the follow-up period.

♦ Results

The mean weekly Kt/V at initiation of dialysis was 2.09. Median actuarial survival on a single exchange before requiring incremental dialysis was 297 days. At the end of the study period, all patients were still alive: 8 remained on 1 exchange, 18 were on more than 1 exchange, 8 had switched to hemodialysis, and 5 had received renal transplants. During the 12 665 patient-days on single-exchange dialysis, there were 14 hospital admissions of 12 patients. This resulted in a mean of 1.64 hospital days per patient–year for the whole group. During the follow-up period there were 2 episodes of bacterial peritonitis, 3 pleural leaks, 1 patent processus vaginalis, and 1 inguinal hernia that required surgical intervention. The use single daily icodextrin exchanges was associated with a 46% incidence of culture-negative peritonitis.

♦ Conclusions

This pilot study has shown that a timely start of dialysis with a single overnight PD exchange is acceptable to patients. Incremental dialysis as residual renal function falls is easily managed and patients also find this acceptable. Complication and hospitalization rates were low. The presence of residual renal function often allows complications to be managed without the need for hemodialysis. The use of icodextrin as a single-exchange dialysate is associated with sterile peritonitis in a significant proportion of cases.

Culture-Negative Peritonitis Associated with the use of Icodextrin-Containing Dialysate in Twelve Patients Treated with Peritoneal Dialysis

← Background

In the first half of the year 2001, an unusually large number of culture-negative peritonitis episodes occurred in Center A. One patient noticed that his culture-negative antibiotic-resistant peritonitis promptly cleared after inadvertently stopping the use of icodextrin-containing dialysate, but recurred immediately after using icodextrin again. This observation led to the recognition of eight contemporaneous cases of icodextrin-induced culture-negative peritonitis in Center A, and identification of three additional cases in Center B.

← Design

Case studies in 12 patients.

← Setting

Peritoneal dialysis unit of a university hospital and an affiliated unit (Center A), and a second university hospital (Center B).

← Patients

12 patients on peritoneal dialysis presenting with culture-negative peritonitis.

← Results

At presentation, abdominal pain was absent or mild and dialysate leukocyte counts were moderately elevated (approximately 100 – 1500 cells/mm3). Differentiation of the dialysate leukocytes showed a low fraction of neutrophils (approximately 35%). In eight cases, the evidence that the peritonitis was caused by icodextrin was very strong (the clinical picture and laboratory results mentioned above, unresponsiveness to antibiotic therapy, cure after withdrawal of icodextrin, relapse after rechallenge); in 3 patients, the evidence was strong (as in the cases mentioned above, but no rechallenge was performed). Stopping icodextrin promptly relieved the symptoms and normalized the dialysate leukocyte counts. After rechallenge, a relapse invariably occurred, usually within a few days. In one case, the evidence was circumstantial.

← Conclusion

Our findings are compatible with icodextrin-induced peritonitis. This entity is characterized by mild abdominal pain at presentation, a moderate dialysate leukocytosis with a low fraction of neutrophils in the differential count, and resistance to antibiotic treatment. Speculations about the pathogenesis of this type of peritonitis include chemical peritonitis due to a contaminating substance or hypersensitivity to icodextrin.

Polyvinyl alcohol gel prevents abdominal adhesion formation in a rabbit model

OBJECTIVE

To evaluate the function and biocompatibility of the new adhesion barrier PVA gel (polyvinyl alcohol + carboxymethylated cellulose) in the prevention of postsurgical peritoneal adhesions in a rabbit sidewall model. To evaluate and compare the routinely used 4% icodextrin.

DESIGN

A prospective randomized controlled study was designed to evaluate the effectiveness of PVA gel in reducing postoperative adhesion formation.

SETTING

Clinical laboratory in Germany.

ANIMAL(S)

Eighty female albino rabbits (HM Small Russian; 2.4-3.6 kg).

INTERVENTION(S)

All animals underwent trauma of the abdominal sidewall at the clinical laboratory. The PVA gel was placed at the sidewall defect in 50 cases. In two further groups, 18 animals had no treatment (control group), and 12 animals were treated with 4% icodextrin.

MAIN OUTCOME MEASURE(S)

Biocompatibility, mechanical properties of PVA gel, adhesion development, and device handling were observed.

RESULT(S)

The PVA gel showed good biocompatibility, no side effects, and excellent adhesion prevention. Although 100% of the untreated control group as well as the animals treated with 4% icodextrin developed adhesion formation, only around 25% of those rabbits that were treated with PVA gel showed adhesions.

CONCLUSION(S)

These data show that PVA gel functions as an excellent adhesion barrier.

Icodextrin-induced peritonitis: study of five cases and comparison with bacterial peritonitis

BACKGROUND

An epidemic of aseptic peritonitis related to the presence of peptidoglycan contaminant in some batches of icodextrin solution (Extraneal, Baxter Healthcare Corporation) occurred in Europe in the first six months of 2002.

METHODS

By case-control study we examined the clinical and biologic features of 5 patients with icodextrin-induced peritonitis (group AP) and compared them with 7 patients with bacterial peritonitis (group BP) recruited in our clinical center between January and June 2002.

RESULTS

Diagnosis of icodextrin-induced peritonitis was confirmed in all cases by a positive reintroduction test with contaminated batches of icodextrin. No recurrence was observed on re-exposure to icodextrin free of peptidoglycan. Skin tests were positive with contaminated icodextrin in 2 of 5 patients, while they were negative with icodextrin solution free of peptidoglycan (<0.6 ng/mL). During peritonitis, serum level of C-reactive protein (CRP) was lower in group AP (42.4 +/- 34 mg/L) than in group BP (135 +/- 59 mg/L) (P= 0.01). Leukocyte number in peritoneal dialysis effluent was lower in group AP (284 +/- 101/mm3), with a lower neutrophil/monocyte ratio (N/M = 0.67) than in group BP (1410 +/- 973/mm3; N/M = 4) (P < 0.05). A low number of peritoneal fluid eosinophilia (11 +/- 8%) was detected in group AP.

CONCLUSION

Icodextrin-induced peritonitis was associated with a burst of intraperitoneal cytokines. The phenotype of peritoneal neutrophils was different between aseptic and bacterial peritonitis, indicating that inflammatory stimuli that activate neutrophils in both types of peritonitis are clearly distinct. Finally, peritoneal injury measured by weight gain, peritoneal permeability, and CA125 concentration seemed to be less severe during icodextrin-induced peritonitis than during bacterial peritonitis.

Relapsing culture-negative peritonitis in peritoneal dialysis patients exposed to icodextrin solution

BACKGROUND

Icodextrin is a new peritoneal dialysis fluid, with maltose polymers providing the osmotic drive, that may extend time on peritoneal dialysis in situations in which use of conventional glucose-based peritoneal dialysis fluid (Dianeal) has led to loss of ultrafiltration. Although cutaneous reactions have been reported, we report a new phenomenon of aseptic peritonitis that has arisen in our unit associated with icodextrin use.

METHODS

Icodextrin was first introduced in our unit in 1997 and was used extensively beginning in late 1999. From a combination of an observational study of 141 patients in our unit in whom icodextrin was used over 3.5 years and our unit 2000 and 2001 peritonitis audits, we identified an increase in the incidence of culture-negative peritonitis (CNP).

RESULTS

The rate in 2000 of 12.3% rose to 17% in 2001, but this increase was seen only in patients on icodextrin (Percentage changes 2000 audit > 2001 audit: icodextrin patients, 14%--31% increase; Dianeal alone, 12%--10% increase; P < 0.05). Six patients were affected in the period 2000 to 2001 out of a total of 141 patients exposed to icodextrin (4.3%). Two index cases of relapsing CNP responded after withdrawal of the icodextrin. We then adopted a protocol of cessation and rechallenge with icodextrin when dealing with CNP, which successfully confirmed the phenomenon and led to resolution of relapsing CNP after icodextrin withdrawal. All these patients had been on icodextrin for some time, and none had had an immediate reaction or any skin reaction. Eosinophils were reported in the peritoneal effluent from two patients. All patients continued Dianeal without further CNP episodes.

CONCLUSION

Icodextrin use carries the risk of CNP, and we suggest a cessation and rechallenge protocol in all patients on icodextrin who have CNP.