Indications for vancomycin in dialysis patients

Resistance to vancomycin has emerged among Staphylococcus aureus, coagulase-negative staphylococci (CNS), and enterococci, and this emergence has particular prevalence in dialysis units. It has therefore become imperative that physicians use vancomycin judiciously. General recommendations regarding the appropriate use of vancomycin have been developed. Although in theory implementation of these guidelines should not be difficult, the medical community may be unable or unwilling to make the necessary adjustments in practice. The onslaught of cost constraints and bureaucratic encumbrance has occurred simultaneously with the increase in vancomycin resistance among pathogens commonly isolated among the dialysis population. When a patient responds to empiric antibiotic therapy and susceptibility data indicate that an antibiotic other than vancomycin would be appropriate, the clinician far too often does not make the change to this alternative. Previously there was no biological imperative to change the antibiotic. That complacency has infected an entire generation of physicians, and especially nephrologists. Furthermore, there is an active movement against change, driven by concerns such as malpractice accusations and frank errors in the interpretation of medical facts.

Increased resistance against acute polymicrobial sepsis in mice challenged with immunostimulatory CpG oligodeoxynucleotides is related to an enhanced innate effector cell response

Recent reports support the concept that the major defect in polymicrobial sepsis is an impaired immunologic response to infection. Oligodeoxynucleotides containing CpG sequence motifs (CpG-ODN) were previously shown to induce immune protection in models of chronic infection with intracellular bacteria, parasites, and viruses due to their ability to augment IFN-gamma-dependent Th1 responses. Here, we demonstrate that challenging mice with CpG-ODN substantially increases the resistance against acute polymicrobial sepsis. Systemic levels of IL-12, IL-18, and IL-10 were not altered in CpG-ODN-treated mice as compared with controls. In contrast, administration of CpG-ODN resulted in a strongly enhanced accumulation of neutrophils at the primary site of infection. Neutrophils of CpG-ODN-treated mice exhibited an up-regulation of phagocytic receptors, an increased phagocytic activity, and an elevated production of reactive oxygen metabolites. These results suggest that the protective effects of CpG-ODNs in acute polymicrobial sepsis are related to an enhanced effector cell response of innate immunity. CpG-ODN may therefore represent potent agents for the treatment of sepsis-associated immunoparalysis.

Peritoneal dialysis. Prevention and control of infection

In spite of the reduction in peritonitis and catheter-related infection rates in patients undergoing peritoneal dialysis, these infections remain major sources of morbidity and transfer to haemodialysis. Touch contamination at the time of doing the exchanges is still a major cause of peritonitis and leads to Gram-positive organisms (coagulation-negative staphylococcus) being the most common pathogens. Newer exchange techniques have reduced this incidence but the more serious pathogens (Staphylococcal aureus, pseudomonas and fungi) remain a major problem. Treatment has to be immediate, and hence empirical, giving adequate cover for both Gram-positive and Gram-negative organisms. The use of vancomycin as an initial antibacterial has been discontinued because of the problem of vancomycin-resistant enterococcus. Recent guidelines advocate the use of a first generation cephalosporin combined with ceftazidime (if the urine output is >100 ml/day) or an aminoglycoside in anuric patients. Subsequent therapy changes are made upon bacterial isolation and sensitivities. Vancomycin is reserved for methicillin-resistant staphylococcus. Peritoneal catheter-related infections (exit site and tunnel) are predominantly caused by S. aureus and pseudomonal organisms and can be difficult to eradicate. Tunnel infections invariably involve the catheter dacron cuffs and therefore are more likely to lead to peritonitis; in this situation catheter removal is the treatment of choice. Treatment of exit-site infections is with oral antibacterials (penicillinase-resistant penicillins, cefalexin). Vancomycin is avoided if possible. The identification that nasal carriage of S. aureus predisposes to exit-site and tunnel infections has led to prophylactic regimens to combat this problem. Mupirocin applied at the exit site leads to a reduction in catheter-related infections and peritonitis.

Immunotoxic effects during acute ethylene glycol poisoning

Experiments on outbred and inbred male CBA mice showed that acute poisoning with ethylene glycol (0.8 LD50) increased mortality from infections, decreased the number of spleen colony-forming units, inhibited antibody formation (mainly to thymus-dependent antigens, and suppressed natural and antibody-dependent cytotoxicity and delayed-type hypersensitivity. Ethylene glycol in concentrations of 10 and 100 mM in vitro inhibited the formation of antibody-producing cells by acting on T and B lymphocytes.

The effects of inhibiting leukocyte migration with fucoidin in a rat peritonitis model

OBJECTIVES

To study the effects of fucoidin on leukocyte rolling and emigration and bacterial colonization in a peritonitis sepsis model in rats.

DESIGN AND INTERVENTIONS

A controlled study in 64 male Wistar rats, anesthetized and rendered septic by cecal ligation and puncture (CLP). Immediately after CLP 32 animals received a continuous infusion of fucoidin and 32 a continuous infusion of Ringer's lactate.

MEASUREMENTS AND MAIN RESULTS

Systemic leukocyte counts were determined every 2 h after CLP. Surviving animals were anesthetized 24 h after CLP, and intravital measurements of leukocyte rolling in venules in the cremaster muscle were performed. The animals were then killed and their organs harvested for histological and microbiological examinations. The 24-h survival was comparable in the two groups. Fucoidin-treated animals had higher leukocyte counts in the systemic circulation and lower counts in the lungs, liver, abdominal cavity, and brain than control animals. The number of bacterial colony forming units in the abdominal cavity, lungs, liver, brain and blood did not differ in the two groups. Fucoidin treatment changed the type of bacteria predominantly found in the examined organs from Escherichia coli to Pseudomonas aeruginosa.

CONCLUSIONS

In an intra-abdominal model of sepsis we found that treatment with fucoidin induces leukocytosis inhibits leukocyte rolling and reduces leukocyte emigration in the abdominal cavity, lungs, and liver. Reduction in the number of emigrating leukocytes was not associated with an increase in bacterial counts found in the examined organs.

Influence of sequential cultivation on virulence of Legionella pneumophila and Staphylococcus aureus

Virulence of Legionella pneumophila strain Monza 3 and Staphylococcus aureus strain Smith diffuse was investigated after sequential cultures on nutrient media. L. pneumophila lost its ability to multiply within Acanthamoeba polyphaga after 50 passages on Legionella selective agar, while S. aureus maintained its pathogenicity in the mouse peritonitis model after 100 sequential cultures on tryptic soy agar. These results demonstrate high preservation of virulence in staphylococci in contrast to legionellae. Differentiation of virulent and avirulent phenotypes of legionellae by the protozoal model may be helpful for detecting sources of infection in water hygiene.

Aerobic and anaerobic microbiology in intra-abdominal infections associated with diverticulitis

The aerobic and anaerobic microbiology of intra-abdominal infections associated with diverticulitis was studied in 110 specimens from the peritoneal cavity after intestinal perforation and in 22 specimens from abdominal abscesses. Anaerobic bacteria only were isolated from 17 (15%) of the peritoneal specimens, aerobic bacteria only from 12 (11%) and mixed aerobic and anaerobic flora from 81 (74%). A total of 339 bacterial isolates was detected in peritoneal cultures (3.1 per specimen), comprising 155 aerobes (1.4 per specimen) and 184 anaerobes (1.7 per specimen). Anaerobic bacteria only were isolated in 4 (18%) abscesses, aerobes alone in one (5%) and mixed aerobic and anaerobic flora in 17 (77%). A total of 72 bacterial isolates (3.3 per specimen) was detected in abdominal abscesses - 35 aerobes (1.6 per specimen) and 37 aerobes (1.7 per specimen). The predominant aerobic and facultative bacteria in abdominal infections were Escherichia coli and Streptococcus spp. The most frequently isolated anaerobes were Bacteroides spp. (B. fragilis group), Peptostreptococcus, Clostridium and Fusobacterium spp.

Prevalence and prognostic value of hepatocellular carcinoma in cirrhotic patients presenting with spontaneous bacterial peritonitis

BACKGROUND/AIMS

This study examined the prognostic power of hepatocellular carcinoma in patients presenting an episode of spontaneous bacterial peritonitis treated with 3rd generation cephalosporins or quinolones, and subsequent prophylaxis with norfloxacin until death or transplantation.

METHODS

The study comprises the prospective evaluation of 168 consecutive cirrhosis patients presenting an episode of spontaneous bacterial peritonitis.

RESULTS

Hepatocellular carcinoma was diagnosed in 35 out of the 168 (20%) patients included in the study (10 single; 25 advanced tumors). Renal impairment developed in 82 patients. Resolution of infection was achieved in 90% of the cases, the hospital survival being 70%. Renal impairment, advanced tumor stage, albumin, and GGT showed independent prognostic value for hospital mortality. At the end of follow-up 101 patients had died, the 1- and 2-year survival being 36% and 31%, respectively. Four variables independently predicted survival: advanced tumor (OR: 3.9; p=0.00001), renal impairment (OR: 2.1; p=0.00001), bilirubin (OR: 1.6; p=0.02) and creatinine (OR: 1.3; p=0.03). Advanced tumor retained independent predictability in patients surviving hospitalization (OR: 7.5; p=0.0001), the 6-month survival being significantly lower in patients with advanced tumor (12% vs 57%, p<0.00001).

CONCLUSION

The prevalence of hepatocellular carcinoma in cirrhotic patients with spontaneous bacterial peritonitis is high, and its presence should be actively sought. Advanced tumor impairs both hospital and long-term survival, and should be considered in the design of future trials.

Continuous ambulatory peritoneal dialysis peritonitis due to Enterococcus cecorum

Enterococcus cecorum was isolated as the etiologic agent of a continuous ambulatory peritoneal dialysis peritonitis episode in an alcoholic patient. To date, this is only the third infection due to this bacterium, found in the intestinal tract of many domestic animals, that has been reported in humans.

Serum and ascitic procalcitonin levels in cirrhotic patients with spontaneous bacterial peritonitis: diagnostic value and relationship to pro-inflammatory cytokines

OBJECTIVE

To assess the potential role of procalcitonin and pro-inflammatory cytokines, TNF-alpha, and IL-6, in the diagnosis of spontaneous bacterial peritonitis (SBP).

DESIGN

Prospective study.

SETTING

The emergency unit of a teaching hospital.

PATIENTS

We included 21 patients with SBP and 40 patients with sterile ascitic fluid.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

For the diagnosis of SBP, the best markers were serum levels of procalcitonin with a cut-off value of 0.75 ng/ml, a sensitivity of 95%, a specificity of 98%, and ascitic fluid levels of IL-6 with a cut-off value of 5,000 ng/ml, a sensitivity of 100%, and a specificity of 88%. C-reactive protein and serum polymorphonuclear count have low sensitivity/specificity at 62/92% and 57/90%, respectively. From 21 patients with SBP, ascitic fluid to serum ratio of TNF-alpha and IL-6 was greater than to 2 in all cases with a mean at 6.2 +/- 6.5 and 34 +/- 31, respectively. By contrast, this ratio for procalcitonin was less than 1 in all cases with a mean at 0.31 +/- 0.25. We found no correlation between procalcitonin levels and cytokine levels in either ascitic fluid or serum.

CONCLUSIONS

Serum procalcitonin level may become a useful marker for the diagnosis of SBP in cirrhotic patients. The low ratio of ascitic fluid to serum procalcitonin supports the hypothesis that procalcitonin is not produced intraperitoneally.

Decreased systemic polymorphonuclear neutrophil (PMN) rolling without increased PMN adhesion in peritonitis at remote sites

BACKGROUND

Previous in vitro studies have demonstrated that the host response to intra-abdominal infection produces increased generalized polymorphonuclear neutrophil (PMN) adherence to vascular endothelial cells (ECs), which may lead to subsequent endothelial damage, leaky capillaries, and organ dysfunction. There are scant data to demonstrate this enhanced systemic PMN adherence in vivo or the influence of PMN rolling on PMN endothelial adherence.

HYPOTHESIS

Systemic PMN adherence in the animal with sepsis is increased.

DESIGN

In vivo murine model of a 2-front infection using intravital microscopy of the cremasteric muscle to quantify PMN-EC adherence in a septic response.

SETTING

Basic science laboratory and animal surgical facility.

PATIENTS OR OTHER PARTICIPANTS

One hundred CD1 male mice.

INTERVENTIONS

Animals underwent cecal ligation and puncture peritonitis, cremasteric muscle Escherichia coli infection, both infections, or neither (controls). Eighteen hours later, the mice underwent exteriorization of the cremasteric muscle under an intravital microscope for measurement of PMN-EC interactions. Blood was then drawn for calculation of circulating PMN counts.

MAIN OUTCOME MEASURES

Adherence of PMNs, PMN rolling flux, PMN rolling velocity, and circulating PMN counts.

RESULTS

Circulatory mechanics did not differ between the groups. Unlike static in vitro systems, we could not detect an increase in PMN adherence after peritonitis with this dynamic in vivo model. A local (cremasteric) infection was associated with marked PMN adherence. Peritonitis was associated with reduced PMN adherence at a local infection site as well as reduced rolling adhesion and PMN rolling velocity.

CONCLUSIONS

The data suggest that intra-abdominal infection does not increase remote PMN adherence, and may actually result in reduction of systemic adherence via modulation of PMN rolling.

[Antibacterial therapy of patients with inflammatory necrotic pancreatitis]

The infectionized necrotic pancreatitis (NP) course, complicated by localized and diffusive peritonitis, abscess and retroperitoneal phlegmon in 86 patients, was analyzed. Severity of state of patients according to the APACHE II scale was estimated. Recommendations for application of empirical and purposeful antibacterial therapy was elaborated. Total mortality for infectionized NP with complicated course was 25.5%.

[Peritonitis with Mycobacterium avium complex in a patient with alcoholic cirrhosis]

Before highly active antiretroviral therapy were available, disseminated Mycobacterium avium complex infection was common in adults with HIV. Diagnosis was often made by blood culture in these immunocompromised patients. Although Mycobacterium avium complex disease can involve any organ of the body, infection of serosal surfaces is very rare. Mycobacterium avium complex peritonitis is rare and usually occurs in immunocompetent patients with chronic ambulatory peritoneal dialysis. We report a case of Mycobacterium avium complex peritonitis in a patient with alcoholic cirrhosis with no evidence of HIV infection. Diagnosis was made by culture of a lymphocytic ascites which showed Mycobacterium avium complex at 4 weeks. Interestingly, blood and hepatic cultures remained negative. At three months, marked improvement occurred with antimycobacterial treatment, so that orthotopic liver transplantation could be performed.

Parameters for determination of Candida albicans virulence in murine peritonitis

Using intraperitoneal (i.p.) infection of mice with Candida albicans we determined which parameters might be useful for characterization of virulence in this model. Upon i.p. infection of mice with two reference strains striking differences in lethality were detected. These differences in virulence corresponded with invasion of the liver and pancreas by the virulent strain and with a lack of invasion by the avirulent strain. The virulent strain was able to release high amounts of the enzymes alanine aminotransferase (ALT) and alpha-amylase (AM) from liver and pancreas into the blood plasma. Most likely, these enzymes were released by penetration of hyphae into the cytoplasm which was shown with electron microscopy. When invasion slowed down, there was also a drop in the activities of ALT and AM measured in the blood of infected mice. As both strains disseminated to the heart, kidneys, and lungs, dissemination into these organs was no reliable parameter for virulence in this model. However, only the virulent strain was able to reach the brain and to germinate in the kidneys and brain. In contrast to invasion and enzyme activities, the fungal load in the peritoneal cavity and in the neighbouring organs appeared not to be related with virulence. This may be concluded from the fact that there were no differences in the absolute colony forming units (cfu) and the length of persistence of both strains when similar inocula were used. We conclude that the ability of a given strain of C. albicans to invade neighbouring organs, to reach the brain upon dissemination and germination in the brain and kidneys may be used for measurement of virulence in this model when virulence is defined as lethality.

Tuberculous peritonitis defying diagnosis: report of a case

A case of tuberculous peritonitis, which has been scarcely encountered in clinical practice in recent years, is reported. A 32-year-old man was admitted to our hospital complaining of abdominal fullness, anorexia, and a 15 kg weight loss. His abdomen was distended. There was neither any previous history nor recent contact with tuberculosis. The laboratory data indicated increased C-reactive protein and erythrocyte sedimentation rate, but the white blood cell count was normal. A chest X-ray examination revealed no abnormalities. Abdominal X-ray showed scattered, small-intestinal gas shadows. Abdominal computed tomography scanning revealed a diffuse thickening of the dilated bowel wall, mainly adjacent to the mesentery. After a detailed examination a diagnosis of peritonitis carcinomatosa of unknown origin was suspected, and an exploratory laparotomy was done. Severe adhesions between the parietal peritoneum and the bowel were found. An excisional biopsy specimen was taken from the peritoneum, and a diagnosis of tuberculosis was thus made. Triple therapy with isoniazid, rifampicin, and kanamycin was started, and both the intestinal obstruction and anorexia were thus resolved.

[Peritonitis determined by the site of intra-abdominal surgery]

The aim of this study was to determine bacterial flora infecting the peritoneal cavity during intraabdominal surgery by site of operation. Three groups of patients were examined. 29 patients who underwent surgery on the stomach, duodenum, biliary tract or pancreas, 15 patients operated on because of acute appendicitis and 63 patients operated on because of colon or rectum tumours. At the end of the operation but before closure cultures were obtained by swab from the completed anastomosis site. Samples were placed into transport medium and transported promptly to the laboratory. The results of the bacteriological examinations showed that the peritoneal cavity of all patients operated on were infected with bacteria characteristic for the digestive tract, especially by Enterobacteriaceae spp., Enterococcus spp. and Bacteroides spp. From patients operated on because of rectum or colon tumours 3 or 4 bacterial species were isolated most often and they were often infected with P. aeruginosa and C. albicans. This was in contrast to patients from the other groups. In patients infected with polymicrobial flora, B. fragilis and E. coli or enterococci and E. coli and enterococci were most often seen.

Fungal peritonitis in children receiving peritoneal dialysis: a report of the NAPRTCS

BACKGROUND

The rarity of fungal peritonitis (FP) in children receiving chronic peritoneal dialysis (PD) has limited the amount of information available regarding the risk factors and management associated with this infection.

METHODS

We reviewed all cases of FP occurring in patients entered into the dialysis registry of the NAPRTCS between January 1992 and May 1996 in an attempt to identify risk factors for infection, treatment strategies, and patient outcome data. A total of 1592 patients who were less than 21 years of age were enrolled in the dialysis registry and received maintenance PD during the period of observation.

RESULTS

Of the total 1729 episodes of peritonitis in these patients occurring over 1732 patient-years of follow-up, FP accounted for 51 (2.9%) of the episodes. The patients on PD who developed FP were similar to those who did not develop FP with regard to race, gender, dialysis modality, and dialysis access characteristics. The overall peritonitis rate in patients who developed FP was 2.2 episodes per patient-year compared with 0.96 episodes per patient-year in the patients who did not develop this infection (P < 0.0001). In 25 (49%) cases, the FP was the patient's initial episode of peritonitis. Whereas recent antibiotic usage was present in 23 (56%) of 41 patients with FP, there was no statistically significant relationship (P = 0.26) noted between the presence of a gastrostomy and the development of FP. Candida species caused 33 of 42 (78.6%) FP episodes. Therapy consisted of PD catheter removal and Amphotericin B in the majority of patients. Six months after diagnosis, 27 patients remained on PD, twelve patients were receiving hemodialysis, and only three patients had died, in each case for reasons unrelated to their FP episode.

CONCLUSION

FP is an infrequent cause of peritonitis in children receiving chronic PD. The presence of a gastrostomy does not appear to predispose patients to the development of this infection, and successful therapy most often consists of a combination of antifungal medication and dialysis catheter removal. The outcome of FP in children appears to be more favorable than in the adult dialysis population.

Aspergillus peritonitis in continuous ambulatory peritoneal dialysis patients

Aspergillus peritonitis is a rare and serious cause of peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients. We report 3 cases of aspergillus peritonitis in CAPD which were successfully treated by catheter removal and amphotericin. Two of the 3 patients returned temporarily to CAPD, but were subsequently transferred to hemodialysis because of membrane failure. A novel finding in 2 of the 3 cases was a positive Limulus amebocyte lysate test, despite negative bacterial cultures. We discuss the possible relevance of this finding to the diagnosis of aspergillus infections and emphasize the importance of early catheter removal for successful treatment of this condition.