Five years' experience of the Italian Registry of Pediatric Chronic Peritoneal Dialysis

The results of the first 5 years' experience of the Italian Registry of Pediatric Chronic Peritoneal Dialysis (CPD) (1986-1990) are presented. Patients of less than 15 years of age at start of dialysis were enrolled and clinical data collected until the age of 19. The number of the dialysis centres participating in the Registry increased from 7 in 1986 to 15 in 1990. The total number of patients on CPD was 119, the number of new patients per year ranged from 15 to 28 and the percentage of all dialysed children treated with CPD increased from 40% in 1986 to 49% in 1990. The age of patients at start of CPD was 8.5 +/- 4.9 years and 16% of them were under 2 years. Only CAPD was utilized in 1986, while CCPD/NPD accounted for 53% and 65% of the treated patients in 1989 and 1990, respectively. At 4 years, patient survival was 91.3% and technique survival 79.3%. A comparison between data of 48 patients on CPD and 34 on hemodialysis, who started dialysis in the period 1989-1990, showed that CPD was the most frequent form of initial therapy (56%) and was the treatment of choice for children younger than 4 years.

Atresia of the left main coronary artery: Clinical recognition and surgical treatment

Atresia of the left main coronary artery is an extremely rare anomaly with very few cases presented in the literature. Even more uncommon are reports of successful surgical repair. This article concerns two cases of atresia of the left main coronary artery treated surgically with a favourable outcome. The two patients (a 16 year-old boy and a 43 year-old woman) had a different clinical presentation but identical angiographic and morphologic features. The authors examine the embryogenetic defect underlying this anomaly. The differential diagnosis involves two congenital malformations (single coronary artery and anomalous origin of the left coronary artery from the pulmonary trunk) and acquired atherosclerotic disease of the left main coronary artery; the distinguishing features of these conditions are reviewed. Surgical management by means of internal mammary artery revascularization is discussed in light of recent reports about adequacy of blood flow in internal mammary artery bypass grafts.

Effect of hemodialysis and hemodiafiltration on uremic neuropathy

This study was undertaken to compare the effect of 1 year hemodialysis (HD) or hemodiafiltration (HDF) treatment on peripheral neuropathy. Thus 21 of 42 patients on chronic HD (1-1.3 m2 cuprophane dialyzer, Qb 300 ml/min) were switched to HDF (1.3 m2 polysulfone dialyzer, Qb 400 ml/min, substitution volume 9-13 liters, ultrafiltration rate 60-70 ml/min), while the remaining patients were considered as a control group. Treatment time was scheduled both in HD and HDF to maintain adequate BUN levels in relation to protein catabolic rate. However, HDF provided a significantly greater weekly inulin (MW 5,000) clearance than HD (5.8 +/- 1.2 vs. 1.6 +/- 0.2 ml/min; p less than 0.001). HD and HDF groups were comparable for age, time on dialysis and starting electroneurographic parameters, which were on average within the normal range. After 1 year follow-up, creatinine, hematocrit, calcium, phosphate, PTH, BUN, protein catabolic rate and residual GFR were comparable in the two groups, whereas beta 2-microglobulin was significantly reduced in HDF patients (29 +/- 6.7 vs. 38.8 +/- 13.9 mg/l in HD patients, p less than 0.01). During the 1-year treatment, electroneurographic parameters did not change in HDF patients, whereas a significant decrease of ulnar motor nerve conduction velocity, ulnar muscle action potential amplitudes, median sensory nerve conduction velocity and peroneal muscle action potential amplitudes was detected in HD patients. We conclude that HDF might prevent the worsening of the electroneurographic indices occurring during chronic HD treatment, as it provides a more effective removal of middle and larger molecules than HD. The use of a more biocompatible membrane in HDF might further contribute to this favorable effect on uremic neuropathy.

Acute coronary occlusion after recent coronary angioplasty. Association with exercise and successful treatment with intracoronary thrombolysis

A case of coronary occlusion occurred seven days after successful percutaneous transluminal coronary angioplasty. The acute complication occurred shortly after a negative exercise stress test and was resolved with intracoronary urokinase.

Improved biocompatibility by modified cellulosic membranes: the case of hemophan

The rising problem of biocompatibility is encouraging the development of new dialysis membranes, but the high cost of synthetic ones precludes their wide use. The authors compared the biocompatibility of cuprophan (CU), cellulose acetate (CA), and hemophan (HE), evaluating both in vitro and in vivo polymorphonuclear leukocyte (PMN) oxidative metabolism activation by resting chemiluminescence and complement activation by C3a; in vivo PMN counts during dialysis were also performed. The lowest increase in in vitro PMN resting chemiluminescence using HE was + 71.3% with CA, +49.3% with CU, and + 21.4% with HE (p less than 0.001 versus CA and CU); furthermore, HE did not significantly stimulate PMN resting chemiluminescence during in vivo hemodialysis: + 56.6% with CA, + 38.8% with CU, and + 3.7% with HE (p less than 0.01 versus CU and p less than 0.001 versus CA). C3a concentration increased with all membranes both in vitro and in vivo, but HE (in both experimental conditions) showed the lowest increase at any time (p less than 0.001 versus CA and CU). After 15 min of dialysis, PMN count dropped to 20.3% of basal values with CU, to 49.8% with CA, and to 76.5% with HE (p less than 0.001 versus CU and CA). Among cellulosic membranes, HE is the most biocompatible and appears to be an important step in preventing blood-membrane interactions and related complications.

Urea determination in dialysis, based on a differential pH technique

The application of a new technique, based on differential measurements of pH, to determine urea concentration in patients of a dialysis center, is reported. Urea in plasma, whole blood or dialysis fluids is measured by an enzymatic reaction, with urease; the procedure, requiring 10 microL of sample, is simple, fast and correlates well with a reference spectrophotometric method, in the 0-300 mg/dL concentration range, according to the equation y = 1.0291 X -0.0777; r = 0.9991; n = 73.

Prolidase deficiency in two siblings with chronic leg ulcerations. Clinical, biochemical, and morphologic aspects

Prolidase deficiency occurred in two sisters suffering from recurrent leg ulcers that appeared in early childhood. The patients presented the typical clinical symptoms of the disease, including characteristic facies, dermatologic manifestations of the lower extremities, splenomegaly, and hematologic anomalies. Large amounts of iminodipeptides were excreted into the urine, and prolidase activity in their erythrocytes was virtually absent. Changes associated with a connective-tissue disorder were demonstrated by light and electron microscopic studies of the patients' apparently normal skin. Collagen fibers were smaller than in controls and were irregularly packed; the fibrils had normal aspect but were significantly smaller than in one age-matched control. Elastin fibers appeared altered both in size and structure.

[Diverticular aneurysm of the right atrium]

A case of right atrium aneurysm (diverticulum) detected in an asymptomatic 61-year-old woman is described. Diagnosis was made according to echocardiographic and echocontrastographic findings and was confirmed by both angiographic data and surgical pathology. The rarity of this finding and the possibility of a correct non-invasive assessment can be considered the two most peculiar features of this case.

[Current status of Senning's physiologic correction of transposition of the great vessels. Personal experience]

From January 1978 to December 1985, 70 children affected by TGA have been operated with the Senning operation. Among the 70 cases, 64 were simple TGA and 6 were TGA + VSD. The mean age at operation was 6 months (range 2 day - 3 years). Of 64 cases with simple TGA, two (respectively of 2 days and 40 days) died with an operative mortality rate of 3.1% of 6 cases with TGA and VSD, one died with a mortality rate of 16.6%. The total mortality was 4.2%. Since 1981 in a continuative series of 47 patients there were no deaths. Our current policy is now the following: after the diagnosis of simple TGA by ECHO, if the Rashkind septostomy is successful, we perform Senning operation over 3 months; if the Rashkind is unsuccessful, we give prostaglandin (PGE1) for a long period (25-30 days) and in case we do a Blalock-Hanlon septectomy. In conclusion we think that in our hands, the policy followed in the treatment of simple TGA is justified by the results achieved but this policy does not prevent us from using different techniques if the results are better.

Renal tubular acidosis associated with vitamin D-resistant rickets. Role of phosphate depletion

3 children with vitamin D-resistant rickets (VDRR), and severe phosphate depletion had moderate metabolitic acidosis and evidence of impaired distal tubular acidifying mechanisms. Therapy with 1-alpha-OH-vitamin D3 and phosphate supplementation improved the clinical and radiological rachitic manifestations, and resulted in the normalization of systemic acid-base parameters as well as of tubular acidification. Profound phosphate depletion is another cause of acquired, reversible distal renal tubular acidosis (RTA).

Plasma levels of chlorodesmethyldiazepam in humans

Chlorodesmethyldiazepam (I) concentrations were followed for 72 h in the plasma of four volunteers given 2 mg of the drug orally. The drug appears to be well absorbed, reaching peak plasma levels of 20--30 ng ml-1 1--2 h after administration; 72 h after administration, plasma concentrations are still measurable (5 ng ml-1). The analytical method involved a single extraction of I from the plasma into benzene followed by centrifugation, evaporation, and gas-chromatographic analysis of the samples.

A safe blood transfusion procedure for immunization against major histocompatibility complex determinants in man

A standardized procedure is proposed for deliberate immunizations against human major histocompatibility complex determinants. The data presented demonstrate its effectiveness and, by using a number of necessary precautions, this procedure has proven to be very safe. The following points are especially important: (1) exclusive utilization of regular blood donors as immunizers; (3) use of whole blood as an immunizing agent; and (3) use of small immunizing stimuli rather than large transfusions. This procedure can be recommended for the production of monospecific anti-HLA antisera and it may be useful if and when a deliberate transfusion policy for prospective kidney recipients is adopted.

"Silent" alleles at the HLA-C locus

Defined specificities of the HLA-C locus possess a significantly lower immunogenicity as compared with the HLA-A and HLA-B specificities. HLA-C "blanks" are not immunogenic at all. Among the possible explanations, the most likely one appears to be a low phenotypic expression of these alleles. C locus antigens as a whole are thus likely to be of minor relevance in donor/recipient matching for transplantation.