Introduction of mycophenolate mofetil and cyclosporin reduction in children with chronic transplant nephropathy

Chronic transplant nephropathy (CTN) is the most important cause of kidney graft dysfunction. Studies in adult populations have reported a beneficial effect of non-nephrotoxic mycophenolate mofetil (MMF) on graft function in this setting. However, few studies were reported in children in this setting. We therefore reviewed the charts/medical records of renal transplanted patients < 18 yr of age at a single center who had switched from azathioprine to MMF as a result of progressive loss in graft function, for which vascular, infectious, and urological causes were excluded. Serum creatinine (SCr) and calculated creatinine clearance were compared prior to and after MMF introduction. Thirteen patients (nine male/four female), followed-up for 59.3 +/- 35.4 months after transplantation, were analyzed. Age at MMF introduction was 14.2 +/- 3.6 yr. In 11 patients a previous biopsy had shown features of CTN and four patients also presented signs of chronic cyclosporin A (CsA) nephrotoxicity. MMF was started at a dose of 1211 +/- 351 mg/day, and the CsA dose was decreased from 6.69 +/- 3.15 mg/kg/day 6 months before MMF to 4.8 +/- 2.3 mg/kg/day at the time of MMF introduction. CsA was withdrawn in four patients. The median (25-75%) SCr value increased from 1.60 mg/dL (range 1.3 to 1.87 mg/dL) 6 months before MMF to 2.2 mg/dL (range 1.87-2.32 mg/dL) when MMF was introduced. Six months after introduction of MMF, the SCr level had decreased to 1.5 mg/dL (range 1.2-1.8 mg/dL) and remained stable until the last follow-up (17.5 +/- 9.2 months after MMF was started). A similar pattern occured with calculated SCr clearance. There were no acute rejections after changes in immunosuppression. The safety of MMF was also analyzed and in only one patient was the drug stopped as a result of intractable diarrhea. These findings suggest that MMF is sufficiently powerful to allow a decrease/withdrawal of CsA without the burden of acute rejection in a pediatric population with CTN.

Comparison of the fluorescent polarization (TDx) and the enzymatic competitive (EMIT 2000) immune assays for the measurement of cyclosporin A blood concentration

Evaluation of Cyclosporin A (CyA) blood concentration is imperative in solid organ transplantation in order to achieve maximal immunosuppression with the least side effects. We compared the results of whole blood concentrations of CyA in 50 blood samples simultaneously evaluated by the fluorescent polarization immune assay (TDx) and the enzymatic competitive immune assay (EMIT 2000). There was a strong correlation between both kits for any range of CyA blood concentration (R=0.99, p<0.001). The within-run and between-days coefficient of variation were less than 4% for both assays. The cost for each CyA measurement was 50% lower for the EMIT assay when compared to the TDx assay. We concluded that the EMIT is as accurate as the TDx in measuring CyA blood concentration and has the advantage of a lower cost, as well as the possibility of widespread access to the EMIT methodology in contrast to the TDx equipment, allowing the laboratory to perform several routines within a working day.

Extraperitoneal access for kidney transplantation in children weighing 20 kg. or less

PURPOSE

We present our experience with kidney transplantation in children weighing 20 kg. or less. Surgery was done via extraperitoneal access while preserving the peritoneal cavity intact with special attention given to technical feasibility and the complication rate.

MATERIALS AND METHODS

Included in our study were 46 children with a median age of 7 years weighing 20 kg. or less (mean 16.6), of whom 16 weighed less than 15 kg. (median 13.2). The 25 boys and 21 girls underwent a total of 49 kidney transplants, including 2 in 3 during the study. Donors were living related in 44 cases and cadaveric in 5. Surgical access was obtained by making a J-shaped pararectal incision in a curvilinear fashion from the symphysis pubis to near the costal border.

RESULTS

Mean hospital stay was 22.9 days (range 6 to 83) and mean followup was 55.8 months (range 12 to 131). All patients received water on day 1 and food on day 2 postoperatively. In 6 patients 7 surgical complications developed, including urinary fistula in 2, superficial wound infection in 2 and vascular complications in 3 (renal vein thrombosis, stenosis and renal artery kinking in 1 each). Only 1 graft was lost due to a surgical complication.

CONCLUSIONS

There are many advantages to using extraperitoneal access without an increase in surgical complications or technical difficulty. Absent gastrointestinal complications, an easier way to perform percutaneous biopsy, treatment of any surgical complication with no need for repeat laparotomy and the possibility of using the peritoneal cavity when dialysis is needed postoperatively are attractive justifications for extraperitoneal access.

Transplantation of horseshoe kidney en bloc

Horseshoe kidney is probably the most common renal fusion anomaly. With the continuous donor shortage, transplant surgeons tend to accept donors previously considered unsuitable. We present a successful case of en bloc horseshoe kidney transplant in a single recipient. The literature is reviewed. The use of horseshoe kidneys in transplantation is recommended in selected cases.

The impact of azathioprine on chronic viral hepatitis in renal transplantation: a long-term, single-center, prospective study on azathioprine withdrawal

BACKGROUND

In transplanted patients, viral hepatitis progresses to chronic liver disease and patient's death after many years of transplantation. Also, it is well known that azathioprine (AZA) is harmful to the liver of these patients. However, it is unclear whether a low dose of AZA still represents a threat to the viral liver disease.

METHODS

A total of 79 patients with hepatitis C, B, or both, transplanted between 1973 and 1990, were grouped according to whether they had AZA either withdrawn from the immunosuppressive regimen [group (G) I, n=45] or a dosage reduction only (group II, n=34). The decision to remove or to keep AZA was restricted to the patient's doctor. Patients records were reviewed by April 1997.

RESULTS

After an equal time of follow-up, after the AZA changing (64+/-26 vs. 58+/-29 months), patients in GI showed a significant decrease in the serum liver parameters when compared to baseline [alanine aminotransferase (ALT): P=0.001; gamma-glutamyl transferase (gamma-GT): P=0.001 and total bilirubin: P=0.002], whereas in GII only ALT decreased (P=0.04) although gamma-GT and total bilirubin did not. Compared to baseline, serum creatinine (SCr) increased only in GI (P=0.001) but, at last follow-up, did not differ from GII. The intention-to-perform liver biopsies was equal in GI and GII (16 vs. 14) but the hystological findings of severe chronic liver disease (either chronic active hepatitis or cirrhosis) were more frequent in GII (P=0.004). Death with a functioning graft was much more frequent in GII than in GI (P=0.001). Infection and cirrhosis were more common as a cause of death in GII than in GI.

CONCLUSIONS

The use AZA is harmful to renal transplantation patients with both chronic hepatitis C and B and, therefore, should be avoided. AZA withdrawal, but not dose adjustments, diminishes the serum liver enzymes and the progression rate of the chronic viral liver disease as well as the rate of death secondary to infection and cirrhosis.

Histological outcome of acute cellular rejection in kidney transplantation after treatment with methylprednisolone

BACKGROUND

Several studies comparing the response of acute cellular rejection (ACR) episodes to different corticosteroid regimens have been conducted. However, in most of them, the histological evaluation of the infiltrate and its correlation with clinical response was not studied. The clinical and histological outcomes of 37 episodes of ACR treated with methylprednisolone (MP) were studied, with the aim to determine how long the infiltrate takes to be cleared after therapy.

METHODS

A total of 37 patients with biopsy-proven ACR were treated with 8 or 16 mg of MP/kg/day. Allograft biopsies were repeated at 5 and 10 days after the end of corticotherapy. Clinical and histological outcomes were compared.

RESULTS

Six patients were excluded; 15 (48.4%) patients responded to therapy; the mean serum creatinine of these patients reached normal levels in the 2 weeks that followed treatment. Nine patients (60%) of this group had signs of ACR on biopsies done 5 days after corticotherapy, and four (26.7%) maintained them on the 10th day. Among 16 patients with no clinical response, none reached normal serum creatinine levels; 15 (93.7%) had signs of rejection 5 days after treatment and maintained them on the 10th day. Histological signs of ACR disappeared in 73.3% of patients with clinical response 10 days after therapy, but in only 6.3% of patients with no response (P=0.001).

CONCLUSIONS

Biopsies performed 5 days after treatment show a high incidence of features of ACR; such features take on average 10 days to disappear in nearly 75% of cases with successful therapy with MP.

Kidney transplantation: the use of living donors with renal artery lesions

PURPOSE

A shortage of organs for transplantation has forced surgeons to optimize the use of marginal organs, such as kidneys with arterial disease. We present a retrospective study of the outcome of donors with renal artery disease and recipients of kidneys from living related and unrelated donors.

MATERIALS AND METHODS

Kidneys with vascular abnormalities from healthy living donors were grafted into 11 recipients. These kidney transplants comprised 1.8% of those performed at our institution. The vascular abnormalities were aneurysms in 3 cases, atherosclerotic lesions in 4 and fibromuscular dysplasia in 4. After nephrectomy all abnormalities were corrected under hypothermic conditions during bench surgery except in 3 cases of ostial atherosclerotic plaque, which was left in the donors. The renal artery was anastomosed to the external iliac artery in 5 cases and to the internal iliac artery in 6. The ureter was reimplanted using an extravesical technique.

RESULTS

All patients had immediate diuresis and no delayed post-transplant graft dysfunction was observed. One patient died of an unrelated cause and 3 had post-transplant graft function loss due to acute vasculopathy in 1, post-diarrhea with acute arterial thrombosis in 1 and recurrence of the hemolytic-uremic syndrome in 1. All remaining patients are well with median serum creatinine of 1.4 mg./dl. (normal 0.4 to 1.4). All donors are well and normotensive with normal renal function.

CONCLUSIONS

The use of kidneys with arterial disease from living donors with unilateral disease is safe. Complete informed consent regarding the risks and benefits by donor and recipient is mandatory.

Role of the peripheral renin profile in predicting blood pressure control after bilateral nephrectomy in renal-transplanted patients

BACKGROUND

The unregulated renin release by native kidneys is one of the factors responsible for the high incidence of hypertension after renal transplantation but, even after three decades of transplantation, there is still a lack of a method to identify it as the major cause of hypertension.

METHODS

We investigated whether or not peripheral renin activity, before and 90 min after 25 mg of captopril, can play this role. One hundred and five consecutive patients with SCr less than 2 mg/dl were studied 18 +/- 8 months after renal transplantation. Forty-seven of them were considered hypertensive and 58 normotensive. All hypertensive patients were submitted to the captopril test to analyse the peripheral renin activity profile.

RESULTS

In the hypertensive group, 17 patients (36%) were considered Renin-pos and 30 (64%) Renin-neg. All Renin-pos (stimulated renin = 19.1 +/- 6.4 ng/ml/h) patients were submitted to bilateral nephrectomy (bNx) and re-evaluated 6 months later. All of them normalized renin activity (4.4 +/- 3.0 ng/ml/h, P = 0.0001) and 10 of 17 (60%) became normotensive and off drugs. The remaining seven (40%) decreased the number of hypotensive drugs from 2.2 +/- 0.5 to 0.5 +/- 0.7/pt/day. There was a correlation between b-Renin and dBP (r = 0.47, P < 0.05) which was lost after bNx. An 'in situ' renal-cell carcinoma was found in two cases. Serum creatinine did not change.

CONCLUSIONS

This study shows that the unregulated renin-angiotensin system from the native kidneys plays a major role in the maintenance of hypertension in some patients with normal graft function and that peripheral renin activity can identify those who will benefit from bilateral nephrectomy.

Contribution of the expression of ICAM-1, HLA-DR and IL-2R to the diagnosis of acute rejection in renal allograft aspirative cytology

Acute rejection is associated with a poor long-term prognosis for renal allografts. Sequential fine-needle aspiration cytology (FNAC) has been used to monitor rejection. However, FNAC diagnoses rejection only when the infiltrating cells are already damaging the graft and, in some borderline cases with a low increment of inflammatory cells in the graft, FNAC lacks the specificity to diagnose rejection. In these cases, the number of inflammatory cells within the graft can decline, stabilize or increase with time. In this study, we sought to determine whether the analysis of the expression of ICAM-I, HLA-DR and IL-2R along with borderline FNAC results increases the specificity to diagnose rejection. Of 117 FNAC samples taken from 24 patients after renal transplantation, 85 (72%) were considered suitable for cytological analysis. Of these patients, 9 (37%) did not suffer an acute cellular rejection (ACR) episode and 15 (63%) had at least one ACR episode. ICAM-1 and IL-2R were studied using an immune-peroxidase technique. The ICAM-1 results are expressed as the percentage of tubular cells in the aspirate stained with this marker and the IL-2R results are expressed as the absolute number of positively stained lymphocytes in the whole cytopreparation. With a total corrected increment (TCI) of > 3 there was a sharp increase in the specificity index for rejection that reached almost 100% at a TCI of > or = 4. Sensitivity for rejection at this level was only 20%. Between a TCI of 2.5 and 2.9 the sensitivity increased to 75%, with specificity for rejection around 75%. There was an upregulation of ICAM-1 and IL-2R when FNAC diagnosed rejection but with a large overlap of the results when compared either to normal graft or acute tubular neurosis. The mean TCI during the week preceding the rejection episode was 2.5 and the TCI reached a mean value of > or = 3 only during rejection. The peak ICAM-1 and IL-2R expression occurred during the week preceding the clinically evident rejection episode. The expression of ICAM-1 by > or = 70% of the tubular cells increased the specificity for rejection of a TCI of > or = 2.5 to 100%. In the same way, the specificity for rejection increased up to 90% when eight to ten IL-2R-positive lymphocytes were seen along with a TCI of > or = 2.5. There was no further increase in specificity after that. A specificity index of 100% for rejection could be obtained for moderate levels of both ICAM-1 (70% or more tubular cells) and IL-2R (eight or more lymphocytes). ICAM-1 expression in 70% or more tubular cells and/or IL-2R expression in eight or more lymphocytes was found in 58% of the FNAC aspirates with a TCI between 2.5 and 2.9. In conclusion, the expression of IL-2R in lymphoid cells and ICAM-1 in tubular cells was upregulated during rejection episodes and the upregulation preceded both the clinical and the routine FNAC diagnosis of rejection by 1 week. The ddition of these markers to the FNAC increased substantially the specificity of the FNAC to diagnose rejection.

Percutaneous needle biopsy of the renal allograft using the automated needle system: evaluation of 87 procedures

Between April 1991 and February 1992 we obtained 87 percutaneous core needle biopsy specimens from 60 patients with the automatic biopsy gun. In 78 cases (89.7%) enough renal tissue was obtained for histological analysis. Acute rejection was present on 35 biopsies (40.3%) indicating antirejection therapy. No pathological signs of rejection were detected on 43 biopsies (49.4%). In 38 instances (43.7%) biopsy diagnosis differed from clinical presumptive diagnosis, affecting patient management, while in the remainder it was helpful to confirm clinical impressions. The only complication of the procedure was gross hematuria (requiring vesical irrigation in 1 patient). Due to its simplicity and low morbidity rate, renal biopsy with the automated needle system is the procedure of choice for evaluation and management of renal allograft dysfunction.

[Survival analysis of 487 patients with kidney transplantation]

The causes of graft loss were analysed in a group of 487 kidney transplants, of which 252 (51.46%) concerned related donors, 139 (28.5%) cadaver donors and 96 (19.7%) non-related donors. A total of 74 kidneys were lost in the first 3 months after transplantation (15.19%). In 34 cases the loss was due to immunological factors (45.9%) in 21 cases (28.3%) to the death of the patients and in 19 cases (25.7%) to the technical causes. From 34 losses by immunological problems, 32 were rejections with humoral character (acute vascular rejection in 11 cases, late humoral rejection in 11 cases, immediate humoral rejection in 9 cases, ABO incompatibility in one case) and recurrence of original disease in one case. Acute cellular rejection was observed in only one patient. None of the patients died from immunological loss of the graft. The most frequent cause of death were sepsis (13 out of 21 patients) and the most common focus of infection was pulmonary (5 patients). It occurred most frequently with cadaveric donor, (10.07%). Death related to cardiovascular causes occurred in four patients, digestive in two and in consequence of arterial bleeding in two. Among the 23 losses by technical factors renal artery thrombosis was the most frequent (11 cases); renal rupture occurred in three cases, renal vein thrombosis in two rupture of arterial anastomosis in one and inviable kidney in another one. The technical loss was most frequent with cadaver donors (8.63%), followed by non-related donors (4.16%) and related donors (2.77%). Four patients died from causes directly related to technical factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Incontinent epispadias: surgical treatment of 38 cases

We review 38 cases of surgically corrected incontinent epispadias with a followup of 5 months to 18 years. In 20 cases the Leadbetter, in 8 the Tanagho and in 8 the Young-Dees techniques of bladder neck reconstruction were used. Of 3 patients with minimal (15 to 25 ml.) bladder capacity the Arap procedure was performed in 1, while small constriction of the bladder neck to improve the bladder capacity and compliance was done in 2. In 1 of the latter patients a 60 ml. capacity was achieved and a secondary Leadbetter operation provided an excellent result. Continence was attained after the initial operation in 18 patients, followup is too short to determine the result in 3 and 15 did not acquire urinary control. Revision of the bladder neck plasty was performed in 11 patients, which resulted in continence in 4 and partial continence in 2. Among 34 patients with an adequate followup 22 (73.3 per cent) are continent and 8 (26.4 per cent) are incontinent. The results were similar with the 3 techniques.

Malakoplakia of the urinary tract

The authors report 4 cases of urinary tract malakoplakia. This rare disease of unknown etiopathogenesis can present with a benign character in the bladder, but when the upper urinary tract is affected, loss of renal function can occur. Treatment aims to control the primary infection, as well as enhance intracellular bactericidal activity, which seems to be compromised in these cases. Cytoreductive surgery may be indicated when this treatment fails.

Sacral agenesis: why is it so frequently misdiagnosed?

Thirty-four patients with sacral agenesis were seen from 1954 to 1983, cases of meningomyelocele excluded. Five recognizable and consistent patterns of bone malformation were identified. Urodynamic examinations were done in 10 of the 34 patients. Their evaluation and response to treatment are analyzed; we tried to determine and establish the possible causes for its late diagnosis and consequences regarding the upper urinary tract.