We initiated a therapeutic program of continuous ambulatory peritoneal dialysis for patients with chronic renal failure. Our program resulted in many episodes of peritonitis arising from contamination due to the technical aspects of the procedure. Microbiologic evaluation showed that 73% of 97 episodes were culture positive, with gram-positive organisms causing most of the cases, especially early in dialysis. Gram-negative rods tended to occur later. Gram stains of dialysate effluent resulted in a disappointingly low yield of only 9% positivity. Cell counts were a dependable indicator of the presence of peritoneal inflammation and also of therapeutic success. Most patients responded well to intraperitoneal cephalothin, 125 mg/L for 10 to 14 d. The occurrence of peritonitis resulted in 0.93 years of hospitalization during the total of 15.45 patient-years on dialysis, which essentially negated the financial advantages of this method of treatment of chronic renal failure. For this to be a successful mode of therapy, advances in the prevention of peritonitis must be made.

In five patients, peritonitis caused by uncommon agents was acquired during continuous ambulatory peritoneal dialysis. Three patients had yeast (two Candida albicans, one C parapsilosis), one Aspergillus fumigatus, and one Nocardia asteroides infections. A review of the literature indicates that yeasts are the most common cause of peritoneal dialysis-associated fungal peritonitis; only one other possible case of Aspergillus sp and no Nocardia infections have been proved, to our knowledge. Observations are recorded in reference to diagnosis and suggested methods of treatment.

Background The presternal peritoneal catheter is composed of two silicone rubber tubes joined by a titanium connector at the time of implantation, and has an exit on the chest. Objective Comparison of survival and complication rates of Swan neck abdominal catheters with those of the presternal catheter. Design Nonrandomized study with prospective collection of data between August 1991 and October 1997. Setting Tertiary referral center. Patients In 57 patients, 58 presternal catheters and, in 81 patients, 86 abdominal catheters were implanted. Patients chose the type of catheter; however, obese individuals and those with ostomies and previous catheter problems were encouraged to opt for the presternal catheter. Others chose the presternal catheter in order to take tub baths or use a whirlpool. Main Outcome Measures Life-table analyses of catheter survival censored for transplant, transfer, and death; reasons for catheter removal due to complications; and patient satisfaction. Results Two-year survival probabilities were 0.95 and 0.75 for presternal and abdominal catheters, respectively. Nine abdominal catheters were removed due to exit/tunnel infections (including five with peritonitis), and four due to peritonitis. External cuff shaving in four presternal catheters has extended survival for more than 1 year. Four presternal catheters were removed due to peritonitis. No catheters in either group were lost due to leakage or obstruction. The peritonitis rate was 1 episode per 37.4 patient-months and 1/20.5 patient-months for presternal and abdominal catheters, respectively. These differences are not significant. Patient acceptance of the presternal catheters was excellent; in the latest period, from January to October 1997, presternal catheters were chosen by 15/24 patients. Conclusions The trend to improved outcomes in presternal catheters continues to validate the rationale for presternal catheter design. Decreased frequency of exit/ tunnel infection may be due to more effective immobilization on the chest, less trauma, and avoidance of submersion in stagnant water. No specific contraindications to use of the presternal catheter have been identified.

There is scanty knowledge of the morphology of peritoneal dialysis catheter tunnels in humans, even though such knowledge may impact on peritoneal catheter design, implantation and postimplantation care. Past descriptions of catheter tunnels are based mainly on data from animal experiments. Based on these data, it has been assumed that epidermal spreading is inhibited by collagen fibers ingrown into the cuff. Our preliminary investigation indicated that this may not be the case in humans and led us to study catheter tunnel morphology in more detail. Eighteen catheter tunnels (2 -Smm of tissue around the catheters) were removed in 17 peritoneal dialysis patients. The catheters were inserted 30 to 2013 days prior to removal (median 366 days). The catheters were removed electively or because of infectious or noninfectious complications. Contrary to the observations in animals, in only 1 case did epithelium extend to the cuff with only a minimal amount of granulation tissue present at the end of a 9 mm long sinus tract. In the remaining cases, the leading edge of the epithelium always met granulation tissue 1 −14 mm from the exit, and the cuffs were found 8 33 mm from the exit. In tunnels older than 197 days, dense fibrous tissue was ingrown into the cuffs, and a dense fibrous capsule surrounded the cuff. The uninfected intercuff segment formed a pseudosheath, indistinguishable from a tendon sheath or synovial membrane. Infection in the catheter tunnel propagates through the part of the cuff adjacent to the tubing inside the capsule, suggesting that the cuff per sedoes not constitute a major barrier for spreading infection. This observation, by exclusion, infers that the beneficial role of an external cuff in decreasing exit infections is by providing firm anchorage of the catheter resulting in restriction of its piston like movement and thereby minimizing trauma and inward conveyance of outer sinus tract flora.