Value of automatized blood culture systems in the diagnosis of continuous ambulatory peritoneal dialysis peritonitis

Peritonitis is a common clinical problem that occurs in patients with end-stage renal disease treated by peritoneal dialysis. The aim of this study was to evaluate the value of blood culture systems for the diagnosis of continuous ambulatory peritoneal dialysis (CAPD) peritonitis among 26 samples of peritoneal fluid obtained from patients with the suspicion of CAPD peritonitis. Significant growth was detected in 12 (70.5%) of 17 bacteria-positive samples. The most striking finding was that 8 (66.6%) of these 12 results were obtained only from blood culture bottles. The identified pathogens were methicillin-sensitive coagulase-negative staphylococci (n = 5), alpha-hemolytic streptococci (n = 2), Corynebacterium spp. (n = 2), Escherichia coli (n = 2), and Enterococcus faecalis (n = 1). Using blood culture bottles inoculated with peritoneal fluid at the bedside, rather than submitting the specimen to the laboratory for later processing, is advocated in the prompt diagnosis of CAPD peritonitis.     

Peritoneal drainage: an important element in host defence against staphylococcal peritonitis in patients on CAPD.

The growth of Staphylococcus aureus and coagulase-negative staphylococci were studied in fresh and effluent peritoneal dialysate from patients on continuous ambulatory peritoneal dialysis (CAPD). Peritoneal drainage during CAPD removes bacterial contaminants from the peritoneal cavity with an efficiency that depends upon the volume of peritoneal fluid remaining after drainage (residual volume). Combination of our data on the growth of coagulase-negative staphylococci in dialysate with a mathematical model of peritoneal drainage during CAPD shows that a residual volume of less than 800 ml (normal = approximately 400 ml) will prevent survival in the peritoneal fluid. A residual volume of less than 200 ml is required to eliminate S. aureus because of its faster rate of growth in dialysate. Previous work has shown that numbers of macrophages are too few to influence bacterial growth in the peritoneal dialysate. Coagulase-negative staphylococci adhere poorly to mesothelial cells in culture. Survival within the peritoneal cavity during CAPD probably depends on colonization of the PD catheter. Coagulase-negative staphylococcal peritonitis is likely to be localized to areas of the peritoneal membrane in close contact with the PD catheter. S. aureus is able to multiply in the peritoneal dialysate during CAPD and thereby causes generalized peritonitis.     

A prospective evaluation of blood culture versus standard plate techniques for diagnosing peritonitis in continuous ambulatory peritoneal dialysis

Peritonitis remains a major cause of morbidity in patients treated with continuous ambulatory peritoneal dialysis (CAPD). Culture-negative episodes of peritonitis occur at rates of up to 20%, and in part may reflect inadequate culturing techniques of peritoneal effluent. Through a large, prospective study, the improved sensitivity of a blood culture system, when compared with a standard plate technique (P = 0.001), for the detection of bacterial growth in 67 episodes of CAPD peritonitis is demonstrated. Improved recognition of infections caused by gram-positive organisms, primarily Staphylococcus epidermidis, was especially significant using the blood culture system (P = 0.0001). Because of improved sensitivity and a decreased time to organism identification, particularly with infections caused by S epidermidis, the most common cause of bacterial peritonitis in CAPD patients, we suggest that a blood culture system be the standard means of culturing peritoneal fluid in CAPD patients with peritonitis. The lysis-centrifugation system of culturing peritoneal fluid is also discussed in comparison with the blood culture system.     

Nontuberculous mycobacterial peritonitis during continuous ambulatory peritoneal dialysis: case report and review of diagnostic and therapeutic strategies

Nontuberculous mycobacteria (NTM) are responsible for an increasing proportion of mycobacterial disease. Peritonitis due to NTM is an unusual but treatable complication of continuous ambulatory peritoneal dialysis (CAPD). Its presentation is similar to that of typical bacterial peritonitis, but special culture techniques are required to avoid a delay in diagnosis. Successful treatment depends on early catheter removal, drainage of fluid collections, and appropriate use of antimicrobial agents. We report a case of Mycobacterium fortuitum peritonitis in a patient undergoing CAPD, and review all previously reported cases. Diagnostic and therapeutic strategies are summarized based on available literature.     

Pulmonary and peritoneal tuberculosis in a CAPD patient

Patients with chronic renal failure have an increased incidence of tuberculosis due to decreased cellular immunity. More than half of the tuberculosis infection in these patients presented with extrapulmonary involvement. Tuberculous peritonitis is an important problem in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Simultaneous pulmonary and peritoneal tuberculosis is a very rare condition. We describe a 39-year-old man with culture negative CAPD peritonitis. In spite of conventional antimicrobial therapy the patient had persistent fever, weight loss, and night sweats. Approximately after one month from starting treatment, both sputum specimen and peritoneal fluid were positive for mycobacterium. Quadruple therapy for tuberculosis has been started. The response to treatment was promptly. He is still on treatment for six months and receiving CAPD. Tuberculous peritonitis should always be considered when patients on CAPD develop culture negative peritonitis treated with conventional antibiotics without improvement. In addition, the existence of extraperitoneal tuberculosis, especially pulmonary disease must be investigated.     

CAPD peritonitis--initial presentation as an acute abdomen with a clear peritoneal effluent.

Accepted criteria for the diagnosis of peritonitis in CAPD include: 1. symptoms and signs of peritoneal irritation; 2. a cloudy effluent with white blood cell (WBC) count greater than 100/microliters and; 3. a positive culture. In fact, the earliest suggestive sign of peritonitis is a turbid effluent. However, symptomatology of peritoneal irritation may precede the development of a cloudy fluid. We hereby report on two CAPD patients with culture proven peritonitis whose initial presentation was that of an acute abdomen. Although diffuse rebound tenderness was elicited the initial effluent, after an overnight dwell, was clear with a WBC count of 80 and 70/microliters, respectively. Working diagnoses on admission included a ruptured cyst and a perforated peptic ulcer. Both patients were in line for a laparotomy. After a period of 7 and 12 hours, respectively the ensuing effluents turned turbid with WBC counts of 6,400 and 2,500/microliters. Cultures eventually grew Staphylococcus aureus and Streptococcus viridans. Appropriate antibiotic treatment resulted in full recovery.     

Usefulness of 23S rRNA amplification by PCR in the detection of bacteria in CAPD peritonitis

BACKGROUND: Peritonitis is the most common complication of continuous ambulatory peritoneal dialysis (CAPD), and the spectrum of organisms causing CAPD peritonitis is broad. Polymerase chain reaction (PCR) has recently broadened its diagnostic capabilities in infectious diseases. PCR can provide a sensitive method for identifying causative infectious organisms. METHODS: To evaluate the usefulness of 23S bacterial ribosomal RNA amplification and direct sequencing for the detection of infectious organisms, we compared PCR with bacteriological culture for the analysis of dialysates from CAPD peritonitis patients. Thirty-two samples from CAPD peritonitis patients with current antibiotic use and control samples from 30 CAPD patients without peritonitis were examined by PCR with sequencing analysis and by conventional bacteriological culture. In addition, 95 culture-positive samples and 39 culture-negative samples from CAPD peritonitis patients before antibiotic treatment were analyzed by PCR assay. RESULTS: In the control samples from patients without CAPD peritonitis, false-positive rates were relatively rare: 3 of 30 in the PCR study and 2 of 30 in the culture study. Of the 134 CAPD peritonitis samples collected before antibiotic therapy, positive cultures were obtained in 70.9% (95/134) of them. In 75 of the culture-positive samples, the same microorganisms were confirmed by PCR assay, and the others showed discrepant results as compared with culture study. In 30 of the 39 culture-negative samples, microbial organisms were detected by PCR assay. Of the 32 samples from patients who developed CAPD peritonitis during antibiotic treatment, 17 (53.1%) were positive by PCR assay, and 5 (15.6%) were positive by culture. CONCLUSION: Our study suggests that broad-spectrum PCR with RNA sequencing can complement culture methods in the diagnosis of CAPD peritonitis, especially in patients with previous or current antibiotic use.     

Serum and peritoneal fluid amylase levels in CAPD. Normal values and clinical usefulness

The mean serum amylase of 42 asymptomatic CAPD patients was elevated but was not significantly different from that of a group of chronic hemodialysis patients. Serum amylase levels in CAPD patients with peritonitis were not elevated with respect to asymptomatic patients. Amylase activity was not detectable in the peritoneal fluid of 38/42 asymptomatic patients and 6/13 peritonitis patients and was present at low levels in the other 11 patients. Patients with other abdominal conditions (pancreatitis, cholecystitis and small bowel perforation) had very marked elevations of serum and/or peritoneal fluid amylase which differentiated them from the asymptomatic and peritonitis patients. Although hyperamylasemia is common in asymptomatic CAPD patients and in those with peritonitis, measurement of serum and peritoneal fluid amylase levels is useful in the evaluation of CAPD patients presenting with abdominal symptoms.     

Treatment of gram-positive peritonitis with two intraperitoneal doses of vancomycin in continuous ambulatory peritoneal dialysis patients

Eight patients with end-stage renal failure on continuous ambulatory peritoneal dialysis (CAPD), who developed peritonitis, received an intraperitoneal dose of vancomycin (30 mg/kg body weight) with 6 h of peritoneal dwell and then resumed their routine CAPD schedule. Vancomycin concentration in serum, peritoneal dialysate (PD) from an overnight dwell and 1, 2 and 3 h after a new exchange was measured at 48 h (in 5 patients) and 7 days (in 6 patients). Except for an occasional 1-hour peritoneal fluid sample on the 7th day, all samples had satisfactory vancomycin levels. Five of the 8 patients who had gram-positive peritonitis and 1 with 'sterile' peritonitis received another similar intraperitoneal dose of vancomycin at the 7th day. All of these patients had good therapeutic response with a negative PD culture 3 weeks after the cessation of therapy and no relapse of infection in at least 1 month of follow-up. We conclude that 2 intraperitoneal doses of vancomycin (30 mg/kg body weight) given 1 week apart with 6 h of intraperitoneal dwell is an effective and adequate treatment for gram-positive and 'sterile' peritonitis in CAPD patients.     

Specific characteristics of peritoneal leucocyte populations during sterile peritonitis associated with icodextrin CAPD fluids.

BACKGROUND: Icodextrin dialysate used for peritoneal dialysis contains an iso-molar glucose polymer solution, which provides sustained ultrafiltration over long dwell times and is considered a valuable approach to reduce intraperitoneal glucose exposure. However, several side effects have been described, including abdominal pain and allergic and hypersensitivity reactions. Also, reactions compatible with chemical peritonitis have been reported. Over the period of a few months (January 2002-May 2002), a remarkable increase in the number of continuous ambulatory peritoneal dialysis (CAPD) patients using icodextrin dialysate diagnosed with sterile peritonitis was observed in our unit. METHODS: Five of the CAPD patients using icodextrin dialysate in our unit and diagnosed with sterile peritonitis were screened for leucocyte count and leucocyte differentiation during a follow-up period of 77 +/- 23 days. In addition, expression of CD14, a receptor for lipopolysaccharide (LPS), on the peripheral and peritoneal monocyte population was analysed. These results were compared to CAPD patients suffering from bacterial peritonitis. RESULTS: The peritoneal leucocyte count of CAPD patients using icodextrin dialysate and diagnosed with sterile peritonitis did not decrease significantly before treatment with icodextrin dialysate was interrupted, whereas it currently disappeared within 2-4 days in proven bacterial peritonitis. The sterile, cloudy icodextrin effluent contained an excess of macrophages on the day of diagnosis, whereas in bacterial peritonitis essentially an increase in the granulocyte population was observed. No elevation in the eosinophil population was observed. In contrast to bacterial peritonitis, we observed no increase in CD14 expression on the peripheral and peritoneal macrophages on the day of presentation and during the follow-up period. CONCLUSIONS: Specific batches of the icodextrin CAPD fluids contain a macrophage chemotactic agent, which causes a sustained inflammatory state in the peritoneal cavity. Because no increase in the expression of the LPS receptor CD14 could be observed, the increased peritoneal leucocyte count is probably not caused by LPS or LPS-like (possibly peptidoglycan-like) contamination.     

Phosphatidylcholine and peritoneal transport during peritoneal dialysis

Peritoneal effluent of patients on chronic ambulatory peritoneal dialysis (CAPD) contains a surface-active material (SAM) made up of phospholipids and showing phosphatidylcholine on thin-layer chromatography. This substance drastically lowers surface tension, helps to repel water and has a lubricating effect. The presence of stratified phosphatidylcholine on the peritoneum might narrow the stagnant dialysate fluid layer and situations which can alter the quantity or composition of SAM may affect peritoneal transport and also, perhaps, the formation of adherences. This led us to verify, experimentally, the presence of phospholipids in basal conditions, after CAPD and during peritonitis and to check if addition of phosphatidylcholine to dialysis liquid is able to modify water transport in patients with low ultrafiltration and peritonitis. Phospholipids in the dialysis effluent of patients who have been on CAPD for a long time are lower than observed in the first days of peritoneal dialysis. A more drastic, significant decrease in phospholipids was observed in patients with low ultrafiltration and in patients with peritonitis. Mean ultrafiltration significantly increases in patients with low ultrafiltration and in those with peritonitis during dialysis exchanges containing phosphatidylcholine (50 mg/l) indicating that the latter is able to restore normal physiological conditions.     

The prevalence and clinical features of tuberculous peritonitis in CAPD patients in Turkey, report of ten cases from multi-centers

OBJECTIVE: To determine the rate, risk factors and outcome of Tuberculous Peritonitis (TBP) in patients treated with continuous ambulatory peritoneal dialysis (CAPD) in our units. DESIGN: Retrospectively, we reviewed the medical data of all CAPD patients from 12 centers for TBP, covering the period between 1986 and December 2002. SETTING: All patients were from 12 renal clinics at tertiary-care university hospitals. RESULTS: Ten cases of TBP were identified among the CAPD patients in our centers. There were five male and five female patients with a mean age of 37.2 years. None of the patients had tuberculosis history, 6 patients had predominance of PNL. One patient had coincidental bacterial peritonitis. Two patients were successfully treated without the removal of the Tenckhoff catheter. CONCLUSION: TBP in CAPD patients is a very rare complication. In contrast to predominance of lymphocytes in nonuremic patients with tuberculous peritonitis, CAPD patients with tuberculous peritonitis may have predominance of PNL on examination of the peritoneal fluid. Since TBP has high morbidity and mortality, early diagnosis and treatment of disease are extremely important for improving outcome.     

Mycobacterium tuberculous peritonitis in CAPD patients: a report of 11 patients and review of literature

Background

The aims of the present report were to document our experience of the prevalence of tuberculous peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients, mode of presentation, diagnosis and outcome and to discuss the current published data about catheter removal.

Methods

A retrospective study of CAPD patients with tuberculous peritonitis was done. A minimum of three specimens of peritoneal fluid were examined for acid-fast bacilli smears. The BACTEC 9000 Blood Culture Series of instruments were used for the culture of Mycobacterium tuberculosis. After 2005, patients were treated with anti-tuberculous treatment, and catheter retention was started in our patients.

Results

There were eleven patients (2.6 %) with tuberculous peritonitis among 414 CAPD patients. M. tuberculosis accounted for 4.47 % of all peritonitis episodes. The incidence of tuberculous peritonitis was 1/794 months. There were eight males and three females. The mean age was 49 years. Intestinal obstruction was reported in two patients, and two patients were treated for antecedent peritonitis. One of them had a simultaneous fungal peritonitis. One patient each developed a peritoneo-cutaneous fistula and ultrafiltration failure. Three were successfully treated without the removal of catheter.

Conclusion

Based on the analysis of all published reports of tuberculous peritonitis, there was no significant difference in patient survival between patients in whom CAPD catheter was removed or retained. Tuberculous peritonitis should be considered in patients with neutrophilic ‘sterile’ peritonitis with no response to antibacterial medications, predominance of lymphocytic peritonitis and in bacterial peritonitis not responding to antibiotics. After an early diagnosis, with close monitoring, an effort to retain the catheter after 5 days of anti-tuberculous therapy may be attempted.     

胰岛素不同给药途径对CAPD患者腹膜炎发生率的影响

目的 探讨终末期糖尿病肾病患者腹膜透析时胰岛素不同给药途径对腹膜炎发生率的影响,为合理使用胰岛素、减少腹膜炎发生率提供临床依据.方法 将47例终末期糖尿病肾病行持续非卧床腹膜透析(CAPD)患者随机分为腹腔组(23例)和皮下组(24例),腹腔组行腹腔给药(胰岛素加入腹膜透析液中行CAPD治疗),皮下组予皮下注射胰岛素.比较两组患者腹膜炎发生率并分析其发生原因,胰岛素用量、费用,低血糖事件发生率及血糖控制水平.结果 两组患者腹膜炎发生率、血糖控制水平、低血糖事件发生率比较.差异无统计学意义(均P>0.05);腹腔应用胰岛素剂量是皮下注射胰岛素剂量的2倍,但腹腔给药比皮下注射费用低4.73倍.发生腹膜炎的原因主要为已培训人员操作不规范及更换未经正规培训的人员操作.结论 在规范培训、严格考核、定期追踪随访CAPD患者的情况下,胰岛素腹腔内给药不会增加腹膜炎的发生率,且可减少费用,减轻患者痛苦,为CAPD治疗依从性较好的患者提供了控制血糖的新途径.     

鲎试验在腹膜透析并发革兰氏阴性细菌腹膜炎时的应用

寻求快速诊断腹膜炎的方法，提供选用敏感抗生素的依据。方法应用鲎试验及细菌培养法对５５例次ＣＡＰＤ腹膜炎腹腔引流液标本进行研究，并以非腹膜炎之腹腔引流液标本４０例次作对照。结果Ｇ－细菌腹膜炎１３例，ＬＡＬ全部阳性，敏感性１００％。Ｇ＋细菌性腹膜炎２６例，ＬＡＬ阳性２例（７．６％）。结论ＬＡＬ法是Ｇ－细菌性腹膜炎的快速，简便的诊断方法，为临床早期选用敏感抗生素提供有力证据。     

Use of pure bicarbonate-buffered peritoneal dialysis fluid reduces the incidence of CAPD peritonitis.

BACKGROUND: Advances in bag connection technology have reduced the incidence of peritonitis in CAPD patients but there is little information on the effect of the new peritoneal dialysis fluids. METHODS: We studied the incidence of CAPD peritonitis for about 3 years in 100 incident patients--50 patients dialysed with lactate-buffered solution, pH 5.5 and containing glucose degradation products (GDP) (lactate group), and 50 patients with pure bicarbonate-buffered solution, pH 7.4 and low GDP (bicarbonate group). Patients in both groups were similar in age, sex, length of time on CAPD, connection technology and handling of dialysis. RESULTS: In the lactate group, 74 episodes of peritonitis were recorded compared with 43 in the bicarbonate group, i.e. one episode per 21 patient-months with the lactate dialysis fluid and one episode per 36 patient-months with the bicarbonate dialysis fluid (OR 0.58, 95% CI 0.37-0.91, P = 0.017). A total of 3369 exchanges per episode of peritonitis were recorded for bicarbonate compared with 2004 exchanges per episode of peritonitis in the lactate group. The majority of organisms isolated in both groups were Gram-positive bacteria, with a predominance of the oropharyngeal and cutaneous endogenous flora. Three episodes of fungal peritonitis occurred in the lactate group and none in the bicarbonate group. CONCLUSIONS: Our results suggest that the pure bicarbonate-buffered peritoneal dialysis fluid appears to reduce the frequency of peritonitis in CAPD patients possibly in relation to greater biocompatibility and maintenance of peritoneal membrane structural integrity. Similar results can probably relate to all low-GDP solutions.     

Benefits of Low Dose Immunoglobulin in the Treatment of Refractory CAPD Peritonitis and Longevity of Technical Survival on CAPD

In this study we investigated the long term results of intraperitoneal immunoglobulin (Ig) treatment in continuous ambulatory peritoneal dialyses (CAPD) patients with refractory or relapsing peritonitis. Sixteen CAPD patients (4 female, 12 male) with a mean age of 53 ± 11 years (40–80), with a mean CAPD duration of 46.2 ± 4.8 months (17–75) were included in the study. The patients included had a diagnosis of either refractory or relapsing peritonitis unresponsive to appropriate antibiotic therapy. 0.5 g of Ig was added to every exchange bag qid as an adjunctive therapy to the culture based antibiotherapy for 7 days. Intraperitoneal Ig treatment was found to be successful in treating peritonitis in all but one patient. Interestingly, following Ig treatment, long term peritonitis rate decreased significantly compared to the period before treatment (before: 2.2 ± 0.6 episodes/patient/year vs. after: 0.6 ± 0.17 episodes/patient/year; P = 0.019). The mean CAPD duration after Ig treatment was 30.5 ± 5.4 (4–64) months. Out of 16 patients, one patient who was unresponsive, had his catheter removed and was switched to hemodialysis, and four patients with preexisting ultrafiltration failure or inadequate dialysis problems were transferred to hemodialysis after successful treatment of their peritonitis, one patient was transplanted and 10 patients continued on CAPD. We conclude that low dose Ig treatment may be beneficial in the treatment of refractory or relapsing CAPD peritonitis possibly through restoring impaired host defense within peritoneal cavity. This therapy, by preventing further peritonitis attacks, may prolong survival on CAPD.     

Group B Streptococcus (Streptococcus agalactiae) peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD)

Streptococcus agalactiae typically induces serious infections in pregnant women and newborns. Nonpregnant adult patients can also be infected and mortality rate exceeds 40%. CAPD peritonitis is very rarely induced by S. agalactiae. Seven cases have been described previously and all had a very severe course, which included bacteremia, septic shock and death. A 27-year-old male with end-stage renal disease due to membranoprolipherative glomerulonephritis type I, who was on CAPD for 17 months, was admitted with the clinical and laboratory picture of CAPD peritonitis. Severe abdominal pain, shaking chills and fever 38.5 microC were also observed at presentation. Streptococcus agalactiae was isolated from the peritoneal fluid and blood culture was sterile. Under treatment with ceftazidime and tobramycin (i.p.) and vancomycin (i.v.) cultures became negative after 48 hours, abdominal symptoms resolved after 12 days and WBC count in the dialysate normalized after 14 days. As a possible source of infection the patient's partner was shown to be a vaginal carrier of a clone of S. agalactiae identical to that isolated in the peritoneal fluid. S. agalactiae is a rare cause of CAPD peritonitis with potentially very serious consequences. Anal or genital tract colonization is, in general, the source of contamination with S. agalactiae. The microbiological findings in the case presented here suggest that colonization of the patient or of his close environment may be important in the pathogenesis of S. agalactiae-induced CAPD peritonitis.     

Fungal peritonitis during continuous ambulatory peritoneal dialysis: a report of 17 cases

Seventeen cases of fungal peritonitis and one case of Nocardia asteroides peritonitis were observed in 141 patients during the first 5 years of our continuous ambulatory peritoneal dialysis program (CAPD). Fungal peritonitis accounted for 7% of the episodes of peritonitis observed in this interval. There were eight deaths associated with fungal peritonitis. In only three instances could factors predisposing to fungal peritonitis be identified. We were unable to predict who would develop fungal peritonitis by analysis of nutritional, demographic, or technical factors associated with the dialysis procedure. The diagnosis of fungal peritonitis was easily established using routine blood agar culture techniques. Successful management of these patients included prompt removal of the Tenckhoff catheter and intravenous (IV) administration of amphotericin.     

Brucella peritonitis in a patient on continuous ambulatory peritoneal dialysis with acute brucellosis

Peritonitis is an uncommon complication of brucellosis. Brucella peritonitis in chronic ambulatory peritoneal dialysis (CAPD) patients has not been reported before. A male patient is presented with peritonitis caused by Brucella melitensis who was on CAPD. The source of infection was thought to be unpasteurized, unsalted cheese eaten a month before the onset of symptoms. At the beginning, antibiotic therapy with doxycyline and rifampicin led to a rapid clinical improvement, with disappearance of the organism in the peritoneal fluid. However, peritonitis relapsed after discontinuation of antimicrobial therapy. Successful management required a combination of medical therapy and removal of the Tenckhoff catheter.