Absorption of antibiotics during peritoneal dialysis in patients with renal failure

Successful treatment of extensively drug-resistant Acinetobacter baumannii peritoneal dialysis peritonitis with intraperitoneal polymyxin B and ampicillin-sulbactam

OBJECTIVE

To describe a case of extensively drug-resistant (XDR) Acinetobacter baumannii peritoneal dialysis (PD)-associated peritonitis successfully treated with combination antibiotics, including intraperitoneal polymyxin B, with retention of the catheter.

CASE SUMMARY

A 54-year-old woman with end-stage renal disease receiving chronic PD and recent antibiotic and hospital exposure presented with abdominal pain, nausea, and vomiting. She was found to have XDR A. baumannii PD peritonitis. Treatment was initiated with intravenous and intraperitoneal ampicillin-sulbactam, followed by the addition of intraperitoneal polymyxin B based on susceptibilities. The patient recovered without the need for catheter removal or switch to hemodialysis.

DISCUSSION

The frequency of XDR A. baumannii as a nosocomial pathogen is increasing, and polymyxins are being used more often as part of combination therapy for infections caused by this organism. Neither XDR A. baumannii PD peritonitis nor the use of intraperitoneal polymyxin B has been well described. In our patient, intraperitoneal dosing of polymyxin B was determined based on limited published pharmacokinetic and pharmacodynamic data.

CONCLUSIONS

A case of XDR A. baumannii PD peritonitis was successfully treated with combination antibiotic therapy, including intraperitoneal polymyxin B, without major complications.

Nitrogen losses and cephalothin absorption in peritonitis treated by hourly peritoneal dialysis

The effects of peritonitis on dialysate nitrogen losses were investigated. Eight patients who developed peritonitis while undergoing peritoneal dialysis were compared to seven noninfected dialysis patients. Dialysate protein losses increased during peritonitis, but nitrogen losses into the dialysate did not increase. These findings were caused by reduced urea nitrogen losses in the peritonitis group, which proportionately, more than made up for the increased nitrogen losses from protein. We speculate that the smaller loss of urea nitrogen was due to diminished intake of food. Cephalothin uptake from the peritoneal cavity was unaltered by peritonitis and a dialysate flow rate of 2 L/hour averaged 26 +/- 2 mL/minute and 27 +/- 2 mL/minute in the noninfected and infected groups, respectively.

Protein losses and tobramycin absorption in peritonitis treated by hourly peritoneal dialysis

The effects of peritonitis on dialysate protein losses of IgG, IgA, IgM, transferrin, and complement were investigated. Thirteen patients who developed peritonitis while undergoing peritoneal dialysis were compared with seven noninfected dialysis patients. Dialysate protein losses increased during peritonitis, but IgG, IgA, IgM, transferrin, and complement losses did not. The ratio of the amount of these proteins to the total amount of protein, measured by trichloroacetic acid precipitation, was unaltered by peritonitis, suggesting that albumin is the predominant protein lost during peritonitis. The infected patients absorbed 55% of the administered dose of tobramycin, at 17 mL/min, and the noninfected 44%, at 13 mL/min.

Drug administration in renal failure

Renal failure impairs urinary excretion of drugs and may also modify drug action by alternations in protein binding, distribution, biotransformation and, possibly, by retention of active metabolites. Dialysis adds another variable by altering the blood levels of those drugs soluble in plasma water and therefore available for diffusion or ultrafiltration. Renal insufficiency clearly modifies decisions about the choice and dose of a wide variety of drugs. Although data are accumulating at a rapid rate, available information about the use of drugs in patients with kidney disease is rather limited. The following is a summary of recent information on the use of a variety of drugs frequently utilized in patients with impaired renal function. The guidelines presented here are not absolute, but they are intended to be practical and reasonable, based on current information for adult patients of average size with kidney disease.

A controlled trial of intraperitoneal cephaloridine administration in peritonitis

From a controlled therapeutic trial extending for more than 2 yr and involving 69 patients with appendicitis and peritonitis a clear-cut statistically significant result emerged. There was a major reduction in the incidence of intraperitoneal abscesses using cephaloridine by the intraperitoneal as opposed to the systemic route. After randomized selection into treatment and control groups, cephaloridine, 25 mg/kg was given by injection every 6 hr for 48 hr to the treatment group by i.p. installation and to the control group by systemic injection. Both groups received initial intraoperative peritoneal lavage with normal saline and also continued systemic injections of cephaloridine on postoperative days 3, 4, and 5. Only one out of 36 patients in the treatment group developed a residual intraperitoneal abscess, as opposed to six abscesses developing in 33 patients in the control group. Technical problems and complications of the method were trivial and have not prevented us from continuing and extending the applications of the method.