Prevalence of cholelithiasis in non-diabetic haemodialysis and continuous ambulatory peritoneal dialysis patients

Haemodialyzed (HD) patients have been found to have an increased bile cholesterol level and an increased saturation index in bile. These changes were markedly enhanced in the presence of a low-protein diet. To evaluate whether such changes influence the prevalence of cholelithiasis in patients with end-stage renal failure, real-time sonography was performed to detect the presence of gallstones (GS) in 54 HD (28 males, 26 females, mean age 52.4 +/- 15.4 years) and 39 continuous ambulatory peritoneal dialysis (CAPD; 22 males, 17 females, mean age 59.1 +/- 14.9 years) patients. No patient had diabetes. The patients' charts were reviewed for the following data: age, sex, primary renal disease, obesity (20% above ideal weight), history suggestive of gallbladder disease or previous cholecystectomy, duration of dialysis, and serum cholesterol levels. Overall, cholelithiasis was documented in 12 of 93 (12.9%) patients, 7 HD and 5 CAPD. When comparing the factors outlined above, no significant difference was found between HD and CAPD patient groups, either with or without cholelithiasis. Gallbladder disease was asymptomatic in all except 1 patient who required cholecystectomy. Using a healthy control group consisting of local age- and sex-matched inhabitants, GS were found in 8 of 134 (6%) of them (p > 0.05). We conclude that the prevalence rate of GS in our dialysis population (HD and CAPD) is similar to that of a local general population following a western-style diet, irrespective of dialysis mode.

Acute eosinophilic interstitial nephritis and uveitis (TINU syndrome) associated with granulomatous hepatitis

A 23-year-old male presented with renal failure, cholestatic liver enzyme elevation and uveitis. Percutaneous renal biopsy revealed marked eosinophilic infiltration of the renal interstitium, which made the diagnosis of TINU syndrome (Tubulo-Interstitial Nephritis and Uveitis). Percutaneous liver biopsy showed granulomatous hepatitis, which was not described as a part of TINU syndrome. The diagnostic dilemma and the literature are discussed.

Orthostatic hypoxaemia in dialysed adult polycystic kidney disease patients

BACKGROUND

Recently we observed a unique clinical phenomenon, namely, orthostatic or postural hypoxaemia in a 72-year-old female adult polycystic kidney disease (APKD) patient, maintained on CAPD. Extensive investigations failed to yield a satisfactory explanation for her ambulatory hypoxaemia.

METHODS

To validate our observation, 15 dialysed patients underwent blood gases analyses in both the supine and ambulatory positions (SpO2 and ApO2 respectively). Patients were divided into two groups: group 1 (n-7) whose end-stage renal failure (ESRF) was due to APKD and group 2 (n-8) in whom ESRF was due to other causes. Both haemodialysed (HD) and CAPD patients were included. ApO2 was determined as the pO2 immediately upon standing up. Readings in HD patients were taken at the end of the dialysis session, that is, at the patients' dry weight.

RESULTS

Respective SpO2 and ApO2 of the two groups were 85 +/- 17.1 and 78 +/- 20.5 vs 85.8 +/- 19 and 91 +/- 21 mmHg. Delta change in pO2 defined as the mean decrease (negative value) or mean increase (positive value) of ApO2 in relation to SpO2 was -7.85 (group 1) vs + 5.2 mmHg (group 2), P < 0.005. In group 1, six of seven patients demonstrated a negative delta. In group 2, four of eight showed a positive delta whilst the remaining four had no change in the delta value.

CONCLUSION

Orthostatic hypoxaemia may occur in dialysed patients whose ESRF is due to APKD.

Frequent involvement of the internal cuff segment in CAPD peritonitis and exit-site infection - an ultrasound study

BACKGROUND

The extent of involvement of the subcutaneous Tenckhoff catheter tract in CAPD peritonitis and catheter-related infections is of major therapeutic importance. By definition, both peritonitis and exit-site infections do not involve the catheter tract. However, diagnosis of these infections as well as the more sinister tunnel infection is based mainly on clinical signs.

METHODS

We examined the usefulness of ultrasound examination (US) of the catheter tract in delineating catheter-related (exit-site and tunnel) infections, and their relationship to each other and to peritonitis. CAPD patients with no evidence of peritonitis or catheter-related infections for 6 months prior to examination served as controls. US were performed by one of two experienced radiologists using the Acuson 128XP/10 scanner with a 7-MHz linear transducer. A positive US was defined as an area of hypoechogenicity (indicative of fluid collection) >2 mm in width along any portion of the catheter tract. Findings were localized into segments(S) as follows: S1, limited to external cuff; S2, intercuff segment adjacent to the external cuff; S3, intercuff segment adjacent to the internal cuff; S4, limited to the internal cuff; and S5, involvement extending throughout the catheter tract.

RESULTS

Between March 1993 and January 1995, 39 CAPD patients, all with a double-cuff straight Tenckhoff catheter with the exit site situated above the point of entry into the peritoneum were studied. A total of 56 US were performed divided among 26 episodes of peritonitis, four tunnel infections, 13 exit-site infections,and 13 controls. There were 30 positive US distributed among 16 peritonitis, four tunnel, eight exit site infections and two control patients. The two positive controls went on to develop peritonitis within 1 month of the US. The majority of the US findings (13/16 in episodes of peritonitis and 5/8 exit site infections were localized to segment 4, that is, to the internal cuff region. Apart from a significant increase in width in all infected segments versus a normal tunnel, no differences in size were seen between peritonitis, exit-site, or tunnel infections, nor were there any differences in size and localization in these infections when comparing the offending organism (Gram-positive, negative, or culture negative).

CONCLUSIONS

We conclude that peritonitis and exit-site infections are frequently accompanied by involvement of the catheter tract. The localization of infection to the internal cuff region in cases of exit-site infection probably occurred as a result of downward migration along the catheter tract. This supports the notion that ideally the exit site should be pointing caudally or that the peritoneal catheter have a swan-neck configuration. With regard to peritonitis, infection within the peritoneal cavity appears to extend and involve the internal cuff region. Thus both the internal and external cuffs do not seem to pose an effective barrier against the spread of infection.. Based on our data, we recommend that US be performed as a routine investigation in all cases of exit-site infection and in cases of refractory or relapsing peritonitis.

Nonocclusive mesenteric infarction in continuous ambulatory peritoneal dialysis

Nonocclusive mesenteric infarction has recently been diagnosed with increasing frequency in dialysis patients. Although most reports have concerned patients on hemodialysis, the condition has also been reported to occur in patients on continuous ambulatory peritoneal dialysis. This report describes such a case developing in a woman whose end-stage renal failure was due to adult polycystic kidney disease. Associated predisposing factors were the presence of orthostatic hypoxemia, postural hypotension and extensive atheromatous changes of the abdominal aorta. In keeping with the known difficulty of establishing the diagnosis of mesenteric ischemia, the diagnosis in our patient was also delayed. She was initially thought to suffer from an episode of peritonitis and/or colonic perforation secondary to the performance of a cleansing enema. Only upon showing pneumatosis coli of the right colon on abdominal computerized tomography was the correct diagnosis made. Laparotomy revealed extensive necrosis of the ascending and transverse colon. A total colectomy and ileorectal anastomosis were performed. The patient died on the 17th day following surgery. This case serves to illustrate that mesenteric infarction should be considered in predisposed patients on continuous ambulatory peritoneal dialysis. The presence of peritonitis may mask the underlying pathology and waylay the unwary physician.