Luciana Ghio

Duration of immunity to diphtheria and tetanus in young kidney transplant patients.

Abstract: A considerable proportion of patients with renal transplant, evaluated manyu2003years after transplant, lack protective diphtheria antibody levels, despite primary immunization, but maintain immunity to tetanus. These patients respond to a diphtheria and tetanus booster but the duration of the response is uncertain. This study was undertaken to assess if protective antibodies evoked by primary immunization are lost quickly after transplantation, and whether the extent of the immune response to a booster influences the persistence of protective antibodies. We studied 15 patients (group 1) immediately after renal transplant and 35 patients with renal transplant for 6u2003±u20034u2003yr who received a diphtheria and tetanus booster (group 2). Six patients (40%) of the first group lost protective diphtheria antibodies a median time of 6.5u2003months after transplant. Thirty‐three patients of the second group responded to the booster with normal diphtheria antibody titers (>u20031 IU/mL) in 22 cases and with low titers in 11. Four of the latter lacked immunity to diphtheria at 12u2003months follow‐up. All patients with normal immunity maintained protective levels of diphtheria antibodies. The low responders had a creatinine clearance of 50u2003±u200320u2003mL/min/1.73u2003m2. Tetanus immunity was maintained in almost all patients of both groups. In conclusion, renal transplant patients had an accelerated loss of diphtheria antibodies in the early post‐transplant period. Response to a diphtheria booster identified a group at particular risk, namely the low responders, who may require frequent booster doses. This group had significantly poorer renal function than the normal responders.

Treatment data during pediatric home peritoneal teledialysis

Peritoneal teledialysis (telePD) is a modem-based communication link between the patients cyclers and a computer in the dialysis unit that allows the transmission and storage of a series of automated peritoneal dialysis (APD) treatment data. In order to evaluate the usefulness of telePD in quantifying the problems that may occur during pediatric APD, we retrospectively studied four patients with a median age of 14.1±1.8xa0years during their initial months of telePD. The selection criteria were potential non-compliance in two cases (patients 1 and 2) and catheter malposition or fibrin occlusion in two (patients 3 and 4). The patients were treated using a Fresenius PD Night Cycler with teledialysis software. Thirty consecutive treatments per patient in the 1st and 4th months were examined, and a series of treatment parameters was calculated. The percentage of treatments with alarms and the number of alarms per treatment were high in both the 1st and the 4th month, particularly in patients 3 and 4. The main causes of the alarms were tube kinking, catheter malfunction, fibrin occlusion, and failure of electrical power. The number of shortened treatments significantly decreased in the 4th month of telePD. One non-compliant family was identified during the 1st month of PD, but psychosocial support helped to decrease the number of shortened treatments due to non-compliance in the 4th month. During the 4th month of telePD, the dwell time/total treatment time ratio (which represents the time of contact between the peritoneum and dialysis fluid) increased as a result of technical interventions aimed at reducing the infusion plus drain time. In conclusion, telePD proved to be useful in detecting and solving the clinical and technical problems of APD.

Immunity to diphtheria and tetanus in a young population on a dialysis regimen or with a renal transplant.

Abstract In 54 transplant recipients diphtheria and tetanus immunity after primary vaccination was significantly lower than in 57 control subject and 35 patients on a dialysis regimen. After a booster, tetanus antibodies developed in the transplant recipients and dialysis patients but no diphtheria antibodies developed in two transplant recipients. No adverse reactions, including acute graft rejection episodes, occurred. (J Pediatr;1997:987-9)

Immunity to poliomyelitis, diphtheria and tetanus in pediatric patients before and after renal or liver transplantation

Few studies have considered the safety, efficacy and appropriateness of vaccinations in pediatric patients before and after solid organ transplantation. The aim of this study was to evaluate the immune status after primary vaccination to diphtheria, tetanus and poliomyelitis in pediatric patients before and after hepatic transplantation and to poliomyelitis in pediatric patients before and after renal transplantation. All the patients had received a complete primary immunization schedule for diphtheria and tetanus and poliomyelitis. Immunity to the three polioviruses was evaluated in 56 patients with renal transplant, 27 on chronic dialysis and 33 controls and in 39 patients with hepatic transplant, 25 with chronic hepatic failure and their 36 controls. Immunity to diphtheria and tetanus was evaluated in 52 liver transplant patients, 29 children with chronic hepatic failure and 54 healthy children. Renal transplant patients were less protected and had lower antibody geometric mean titers than healthy controls for polioviruses 1 and 2. Whereas, protection in the children liver transplant patients was similar to that in their controls. Patients with chronic hepatic failure had higher antibody geometric mean titers to diphtheria and polioviruses 1 and 3 than their control group. Immunosuppression after transplantation has a negative influence on the immune status after primary vaccination in children with renal transplant. Whereas children with chronic hepatic failure have higher antibodies than a normal population. When possible, it could be advisable to individualize immunization schedules in patients at high risk.

Dietary prescription based on estimated nitrogen balance during peritoneal dialysis

Abstractu2002Protein and energy requirements of children on automated peritoneal dialysis (APD) have still not been sufficiently well defined, although their adequacy is important to maintain a positive nitrogen (N) balance and prevent malnutrition. We carried out 42 studies to estimate N balance in 31 children over 3 years on APD for 19.8±15.7 months. Twenty metabolic studies were performed in patients dialysed for less than 1 year (7.2±3.3 months) and 22 in patients treated for more than 1 year (31.3±13.6 months). The mean estimated N balance of all metabolic studies was 57.5±62.8u2005mg/kg per day. In only 21 of 42 studies was N balance estimated to be over 50u2005mg/kg per day, which is considered adequate to meet N requirements for all metabolic needs and growth of uremic children. Estimated N balance correlated significantly with dietary protein intake (r=0.671, P=0.0001) and total energy intake (r=0.489, P=0.001). Using the equations of correlation, the values of dietary protein intake [=144% recommended dietary allowance (RDA)] and total energy intake (89% RDA) required to obtain an estimated N balance >50u2005mg/kg per day were calculated. Significantly lower estimated N balance values were obtained in the studies performed on patients on APD for over 1 year (36.09±54.02u2005mg/kg per day) than in patients treated for less than 1 year (81.11±64.70u2005mg/kg per day). In conclusion, based on the values of estimated N balance, we were able to establish adequate dietary protein and energy requirements for children on APD.

Dialysis delivery in children on nightly intermittent and tidal peritoneal dialysis

To achieve more adequate dialysis in a shorter treatment time, seven children, characterized as high/high average (H/HA, 5 patients) and low/low average (L/LA, 2 patients) transporters according to the peritoneal equilibration test, were treated with tidal peritoneal dialysis (TPD) for 13.7 ± 5.7 months, after being treated with nightly intermittent peritoneal dialysis (NIPD) for a similar period. We determined the TPD prescription necessary to provide improved clearances compared with NIPD within the same or less treatment time. Dialysis flow rate was significantly higher in TPD than NIPD, due to a reduction of dwell time and an increase in the number of exchanges. Peritoneal and total clearances of urea and creatinine were higher, whereas serum creatinine and urea nitrogen levels were lower and treatment duration shorter during TPD than NIPD, notwithstanding a decrease of residual renal function. Moreover, a mean time-averaged blood urea nitrogen level as low as 48.5 ± 11.6 mg/dl was achieved during TPD. The improvement was more significant in H/HA than in L/LA patients.

Immune response to hepatitis B vaccine in staff and patients in renal dialysis units

Anti-HBs response was detected in 96 per cent of staff members in three haemodialysis units after three 20 microgram doses of hepatitis B vaccine and in 82 per cent of adult patients treated with three 40 microgram doses. The percentage of responders and levels of antibody remained unchanged at 12 months from the beginning of the trial. Three out of six children injected with three 20 microgram doses in a paediatric haemodialysis unit remained free from markers of HBV infection and had high levels of anti-HBs after the second dose of vaccine. The other three children who developed serological markers of HBV infection seroconverted to anti-HBc within six months from the first dose and, in one of them, antigenaemia at three and four months was detected.

Lipid profile during rhGH therapy in pediatric renal transplant patients

Abstract: To evaluate the effect of recombinant human growth hormone (rhGH) treatment on the lipid profile of pediatric renal transplant patients, we studied nine children treated with rhGH for 1u2003yr and a control group of 12 untreated patients matched in terms of age, renal transplant function and post‐transplant follow‐up. The levels of lipoprotein (a [Lp(a)], cholesterol, triglycerides, apolipoprotein A (APO A) and apolipoprotein B (APO B), and the APO B/APO A ratio, were determined at baseline and after 6 and 12u2003months of follow‐up. RhGH therapy had no effect on cholesterol, triglycerides or apolipoproteins. Mean serum Lp(a) levels increased from 6.7u2003±u20035.7u2003mg/dL at baseline to 11.8u2003±u200310.7 after 6u2003months (p =u200a0.018) and 13.6u2003±u200315.1 after 12u2003months of rhGH treatment (p =u200a0.04), but did not change in the control group. Lp(a) is a risk factor for cardiovascular morbidity, and increased Lp(a) levels may be a side‐effect of rhGH treatment in renal transplant patients. Although long‐term follow‐up of a large number of patients is needed to establish the duration and extent of the effects of rhGH treatment on Lp(a) levels in transplanted children, serum Lp(a) levels should be carefully monitored in those receiving rhGH therapy.

Models to assess nitrogen losses in pediatric patients on chronic peritoneal dialysis.

Abstractu2002To develop models to estimate nitrogen (N) losses of children on chronic peritoneal dialysis (CPD) from easily measurable indexes and laboratory tests, we measured the N content and all nitrogenous compounds in dialysate (D), urine (U), and feces over 3 days in 19 pediatric patients on CPD. Total measured N losses (TNm) were 5.56±2.26 g/day (69.9±11.1% in dialysate, 16.3±10.6% in urine, and 13.6±4.6% in feces). Correlation coefficients between measured dialysate and urinary N losses and the single nitrogenous compounds indicated values of over 0.9 only for urea in dialysate and urine; fecal N losses correlated well with body surface area (BSA). Taking into account these correlations, we developed a univariate additive model and three multivariate models to predict total estimated N losses (TNe). The best prediction of TNm was obtained with model 3, which considered not only urea output in dialysate and urine but also dialysate protein loss and BSA: TNe (g/day)=0.03+1.138 UN urea+0.99 DN urea+1.18 BSA+0.965 DN protein. A confirmatory analysis performed on a second group of 23 pediatric patients on CPD, using all four models, showed a higher percentage of studies with a relative difference between TNm and TNe less than 10% for model 3 than for the other models. Thus, N losses of pediatric patients on CPD can be estimated from measured urea and protein losses in dialysate and urea loss in urine, together with BSA.

Clinical Features and Prognosis in Childhood IgA Nephropathy

Clinical variables and laboratory and histologic findings were evaluated in 53 children with IgA nephropathy, of whom 44 were followed for a mean period of 6.2 years (range 1.2-14). At the end of the follow-up 8 patients (18.2%) had had no urinary anomalies for at least 1 year (stage A disease), 28 (63.6%) had microscopic hematuria with proteinuria < 1 g/m2/day (stage B), 5 (11.4%) had proteinuria > 1 g/m2/day (stage C), and 3 (6.8%) had chronic renal insufficiency (stage D). None of the patients in apparent remission presented with elevated serum IgA levels at disease onset. Gross or microscopic hematuria at onset correlated with stage A/B disease at the end of follow-up (p < .05) whereas the presence of proteinuria or nephritic syndrome at onset correlated with stage C/D disease after follow-up (p > .05). Presenting features of gross or microscopic hematuria without or with proteinuria (< 0.5 g/m2/day) correlated (p < .001) with minimal glomerular abnormalities at biopsy, whereas patients with nephritic syndrome had more severe histologic pictures. The presence of proliferative glomerulonephritis with crescents correlated (p < .0001) with poor outcome. The results demonstrate that the prognosis of IgA nephropathy in childhood must be viewed with caution and that outcome correlates with mode of onset and severity of the renal pathology.