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Biomedical subjects

A Tejani

Publications and source records attributed to A Tejani.

At least 37 records · Page 2Linked to original sources
PubMed1999

Trends in immunosuppressive therapy: a report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS).

The North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) data registry has now compiled data for 11 years, and includes data on 6038 renal transplants in 5516 patients. With the availability of new data and immunosuppressive medications, trends in their usage continue to change. NAPRTCS data have previously demonstrated that increased doses of cyclosporin A (CsA) are associated with improved allograft outcomes, and there has been a steady increase in the dose of CsA given post-transplantation. Transplants that occurred in 1987, 1989, 1991, and 1993 received a mean one-year post-transplant dose of 6.5, 7.0, 7.7, and 8.2 mg/kg/d, respectively. In the 1995 cohort, the dose decreased to 7.4 mg/kg/d. Since the introduction of Neoral, its use has steadily increased. Of the 1997 cohort, 81% report Neoral as the formulation of CsA used. The dose of CsA given, however, has not changed. At day 30 post-transplant, the dose was 7.0 mg/kg/d for Sandimmune and 7.4 mg/kg/d for Neoral. Finally, the outcome in black transplant patients is inferior to that of nonblack. Evaluation of CsA blood levels revealed that at 1 year post-transplant, black patients consistently have CsA levels higher than nonblacks, and a lower percentage of black patients have a CsA level < 100 ng/mL. The percentage of patients using triple therapy (prednisone, azathioprine, and CsA) remained stable from 1987 to 1993 at 80-85%. However, in 1996 only 30% of patients were receiving triple therapy. This is probably due to the introduction of mycophenolate mofetil (MMF). Comparing the 1996-97 cohorts, there has been no significant change in the percentage of patients receiving prednisone (96.2% vs. 95.4%) or CsA (83.1% vs. 79.6%). However, during this time, the use of azathioprine has decreased from 50.0% to 35.8%, the use of tacrolimus has increased from 2.5% to 10.8%, and the use of MMF has increased from 6.5% to 35.8%.

Adolescent↗
PubMed1999

The 1997 Annual Renal Transplantation in Children Report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS).

This report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS), covering the years 1987-96 (January 15, 1997), analyzed data on 4898 patients who received 5362 transplants. Over the 10 yr of the study, 21.3% of the patients were under the age of 6 yr. Of the disorders that lead to end-stage renal disease (ESRD), structural and developmental anomalies of aplasia, dysplasia, and obstructive uropathy accounted for over 1500 patients. Despite the potential therapies for focal segmental glomerulosclerosis (FSGS), there has been little change in its incidence and this lesion continues to be the most common cause of renal failure and transplantation among acquired diseases. Eighty-nine per cent of patients with a functioning graft continue to receive cyclosporin A (CsA) 5 yr post-transplantation, and 84% of patients continue to receive azathioprine (AZA), whereas 26% of patients receive alternate-day steroid therapy at 4 yr post-transplant. Thirty-seven per cent of the living donor (LD) recipients and 47% of cadaver donor (CD) recipients were treated with the polyclonal T-cell antibody ATG/ALG for induction, and the monoclonal T-cell antibody, OKT3, was utilized for induction in 12% of LD patients and in 19% of CD patients. Twenty-five per cent of the 5362 transplants (1333) have failed over the 10-yr period. Graft survival is 90% at 1 yr and 74% at 6 yr for LD kidneys, and is 80% at 1 yr and 58% at 6 yr for CD patients. The most common cause for graft failure (30%) is chronic rejection. For recipients of LD grafts, relative risk (RR) factors for graft survival are African-American race (RR = 2.1, p < 0.001) and greater than five prior transfusions (RR = 1.6, p < 0.001). Prophylactic anti-T-cell antibody reduces the risk of graft failure (RR = 0.76, p = 0.009). For recipients of cadaver kidneys, risk factors are: recipient age < 2 yr (RR = 2, p < 0.001), donor age < 6 yr (RR = 1.3, p = 0.005), and absence of induction T-cell antibody (RR = 1.31, p < 0.001).

Adolescent↗
PubMed1999

Antihypertensive medication and renal allograft failure: a North American Pediatric Renal Transplant Cooperative Study report.

Hypertension after renal transplantation occurs commonly and, in adults, is associated with decreased graft survival. The North American Pediatric Renal Transplant Cooperative Study database was analyzed to determine: (1) the percent use of antihypertensive (anti-HTN) medication based on donor type, race, age, and acute rejection status; and (2) whether use of anti-HTN medication is associated with higher rates of subsequent graft failure. Data regarding anti-HTN medication use was available in 5251 renal allografts (4821 patients) with >30 d graft function. Posttransplant follow-up data were collected at 30 d, 6 mo, 12 mo, and then annually for 5 yr. At each follow-up, patients were selected for further analysis if the graft was functioning at that visit and subsequent follow-up data were available. Overall, anti-HTN medication use was 79% on day 30 and 58% at 5 yr. At each follow-up, anti-HTN medication use was higher (P < 0.01) for cadaveric donor versus living related donor, blacks versus whites, age >12 versus <12 yr, and > or = 1 versus 0 acute rejection episodes. Anti-HTN medication use at each annual follow-up was associated with significantly higher rates of subsequent graft failure. Multiple regression analysis controlling for all factors associated with increased use of anti-HTN medications revealed a relative risk of graft failure for use of anti-HTN medication of greater than 1.4 (P < 0.001). In recipients of cadaveric allografts, only acute rejection status predicted subsequent graft failure more strongly than use of anti-HTN medications. These data suggest that hypertension after renal transplantation in children, as evidenced by use of anti-HTN medications, is associated with increased rates of subsequent graft failure.

Age Distribution↗
PubMed1999

Steady improvement in short-term graft survival of pediatric renal transplants: the NAPRTCS experience.

This report of pediatric renal transplantation covers the years 1987-1998. Since its inception in 1987, the NAPRTCS has collected data on 6,038 transplants performed in 5,516 patients provided by 73 renal centers across the country. FSGS, together with developmental lesions of dysplasia and obstructive uropathy, account for 40% of all transplants. There has been a steady increase in the use of LD donors among children with 54% of all transplants in 1996 and 1997 being live-related. About 72% of LD transplants are performed in Caucasian children, with African-American children unfortunately receiving a disproportionate percentage of CD kidneys. There has been a steady decline in the use of CD kidneys recovered from young individuals and a gradual decline in the number of transplants performed in young recipients (< 6 years old). Graft survival for LD recipients was 91%, 84% and 79% at one, 3 and 5 years, respectively, and the comparative figures for CD recipients were 81%, 72% and 64%, respectively. Acute and chronic rejections account for most of the graft losses, with chronic rejection accounting for more than 30%. There has been a steady improvement in one-year graft survival of CD recipients with the 1997-1998 cohort exhibiting an improvement of 16% over the 1987-1988 cohort. This improvement has been brought about by eliminating the use of infant donor kidneys, reducing the number of random transfusions and increasing the maintenance dose of cyclosporine. Posttransplant growth continues to be poor, with catch-up growth being exhibited only in children under age 6.

Adolescent↗
PubMed1998

The paucity of minimal change disease in adolescents with primary nephrotic syndrome.

Data are sparse regarding the histological lesions associated with the primary nephrotic syndrome in adolescents. To our knowledge there are only two published articles that have specifically addressed the histopathological lesions that typify idiopathic nephrotic syndrome in the adolescent population. We reviewed our experience from the last 14 years of children between the ages of 12 and 18 years who were referred to our center for the evaluation of the nephrotic syndrome. A total of 29 adolescents met the inclusion criteria for this review. All patients were biopsied prior to the initiation of treatment. The sex ratio consisted of 52% males and 48% females and the racial breakdown was largely African-American, with 83% black adolescents, 7% Hispanic, and 10% Caucasian patients. Minimal change nephrotic syndrome (MCNS), the predominant lesion of children at an early age, was noted in only 20% of patients. The majority of patients (55.2%) had focal segmental glomerulosclerosis (FSGS); 7% had IgM nephropathy and 3.5% had diffuse mesangial hypercellularity. Only 7% of biopsied adolescents had membranoproliferative glomerulonephritis. Our results indicate that the most common lesion in this predominantly African-American patient population is FSGS, with only a small number showing MCNS. Thus, in our experience derived from a racially mixed population, adolescents with the nephrotic syndrome are less likely to have MCNS than younger children.

Adolescent↗
PubMed1998

Renal transplantation in Down syndrome: a report of the North American Pediatric Renal Transplant Cooperative Study.

There are few published reports on renal transplantation in patients with Down syndrome and renal failure. By means of a questionnaire sent to participating renal centers of the North American Pediatric Renal Transplant Cooperative Study, this study identified 14 Down syndrome patients who received renal transplants between January 1987 and November 1995. There were 6 males and 8 females between the ages of 6 and 21 years. Of the group, 8 patients were Caucasian and 6 were of African American ethnicity. Four patients had a primary diagnosis of obstructive uropathy, two had hypoplastic/dysplastic renal disease, two had focal segmental glomerulosclerosis, two had a diagnosis of chronic glomerulonephritis and four patients had unspecified diagnoses. Eight patients received cadaver kidneys whilst the other six had a living related transplant from a parent or sibling. Only one patient had received a prior kidney transplant, ten patients were on dialysis at the time they were transplanted and 4 patients were preemptively transplanted. Standard immunosuppression with Cyclosporine, Imuran and Prednisone was used. In addition, nine patients received induction therapy at the time of transplantation. Follow-up data revealed that 5 grafts (35.7%) had failed, two as a result of rejection and three due to patient death. At the time of data cutoff there were 3 deaths, one due to viral infection and the other two secondary to cardio-pulmonary complications.

Adolescent↗
PubMed1998

Sequential analysis of the lipid profile of children post-renal transplantation.

Persistent hyperlipidemia and hypercholesterolemia post-transplantation are risk factors for accelerated atherosclerosis. To evaluate the natural history of lipid abnormalities in children post-transplantation, this study utilized a cohort of 29 patients who were all treated with the same three- drug maintenance immunosuppression (cyclosporine, azathioprine, and prednisone) and whose dosing regimen was rigidly controlled. Fasting blood samples were taken monthly to determine lipid profiles measuring total cholesterol (CHOL), triglycerides (TG), high-density lipoprotein cholesterol (HDL), very low density lipoprotein cholesterol (VLDL), and levels of lipoprotein (a) (LP(a)). A mean value was determined for each of five time periods: 0-3 months, 3-6 months, 6-9 months, 9-12 months and 12-15 months post-transplant. A single specimen of fasting lipid profile was drawn from 21 non-immunosuppressed children attending an ambulatory pediatric clinic and used as control. Despite significant reductions in the cyclosporine and prednisone doses post-transplantation, significant reduction in any of the lipid parameters was only noted after the first year. Reductions in the HDL fraction and in the TG level were noted during the 12-15 month period, however the values obtained in the patient population were significantly elevated for CHOL, TG, LDL and VLDL compared to controls. This study, using a fixed protocol, suggests that the lipid profile should be measured at one year post-transplant in all transplant patients, and if subsequent follow-up continues to exhibit abnormally elevated levels of CHOL and LDL, interventional therapy should be considered.

Adolescent↗
PubMed1997

Risk factors for vascular thrombosis in pediatric renal transplantation: a special report of the North American Pediatric Renal Transplant Cooperative Study.

Vascular thrombosis remains a major cause of graft failure, accounting for 12.2% of failed index transplants and 19.2% of repeat transplants. We conducted a special study to identify the risk factors for vascular thrombosis. A total of 4394 transplants (2060 living donor [LD] transplants and 2334 cadaver donor [CAD] source transplants) were evaluated. The respective vascular thrombosis rates for LD and CAD transplants were 38/2060 (1.8%) and 100/2334 (4.2%) (P<0.001). Univariate analysis showed that the rate of graft loss due to thrombosis was significantly higher in younger children (less than 2 years of age) as compared with older age groups (2-5 years, 6-12 years, and more than 12 years of age) (9.0% vs. 5.5%, 4.4%, and 3.5% for CAD transplant recipients and 3.5% vs. 3.4%, 0.7%, and 1.9% for LD graft recipients). Recipients of kidneys from cadaver donors less than 5 years of age had a significantly higher thrombosis rate (8.3%) than did recipients from older donor groups (5-10 years, 4.5%; greater than 10 years, 3.2%). Recipients of kidneys with cold ischemia time greater than 24 hr also had a higher thrombosis rate (5.6%), as compared with recipients of kidneys with a shorter cold ischemia time (3.2%). Recipients of antilymphocyte therapy on day 0 or day 1 were at dimished risk of graft loss due to thrombosis (2.2% vs. 4.1%, P=0.001). Comparable trends were seen for both LD and CAD organ recipients. LD organ recipients with a history of prior transplantation had a significantly higher rate of thrombosis as compared with those who received a primary transplant (4.6% vs. 1.6%, P=0.005). For both LD and CAD organ recipients, the occurrence of acute tubular necrosis was a significnat risk factor for the development of thrombosis. Regression analysis showed that for LD organ recipients, a history of prior transplantation increased the risk for thrombosis, whereas increasing recipient age had a linear decreasing risk effect. The use of antilymphocyte antibody or cyclosporine on day 0/1 decreased the risk for thrombosis. For CAD kidney recipients, organ cold ischemia time greater than 24 hr increased the risk for thrombosis. The use of antibody induction therapy, donors greater than 5 years of age, and increasing recipient age were factors that decreased the risk for thrombosis.

Age Factors↗
PubMed1997

Renal transplantation, chronic dialysis, and chronic renal insufficiency in children and adolescents. The 1995 Annual Report of the North American Pediatric Renal Transplant Cooperative Study.

The 1995 Annual Report of the North American Pediatric Renal Transplant Cooperative Study summarizes data voluntarily collected from 123 centers on 5,197 children and adolescents grouped into three cohorts: (1) patients who received renal transplants on or after 1 January 1987 (n = 3,066), (2) patients who were maintained on peritoneal dialysis (PD) or hemodialysis (HD) on or after 1 January 1992 (n = 1,488), and (3) patients treated for chronic renal insufficiency (CRI) on or after 1 January 1994 (n = 643). The transplant and dialysis information update previous registry data whereas the CRI information reflects 1st-year registry data. Three-year graft survival rates were 83% and 66% for living donor grafts and cadaver donor (CD) grafts, respectively. Triple drug maintenance therapy with prednisone, cyclosporine, and azathioprine was used by > 70% of all transplant recipients through 5 years of follow-up. The 2-year CD survival has steadily improved from 65% in 1987 to 82% in 1992. Fifty malignancies have been reported, the majority of which are lymphoproliferative disorders. The 2-year patient survival posttransplantation is 95%. Mortality rates for the youngest patients have drastically improved over the past 2 years. Approximately two-thirds of patients in the dialysis cohort are maintained on PD; automated PD remains the preferred modality. Overall, the peritonitis rate is one infection every 13.3 patient months, the frequency of infection being greatest in the youngest patients. Whereas the primary reason for dialysis modality termination is transplantation approximately 40% of the entire dialysis cohort (PD at HD) were not considered active transplant candidate Baseline CRI data revealed the most common primary diagnoses to be obstructive uropathy (24%) and aplastic/hypoplastic/dysplastic kidneys (19%). The standardized height deficit in the CRI cohort was greatest in the younger patients and those with the most impaired renal function.

Adolescent↗
PubMed1997

Immunization practices in children with renal disease: a report of the North American Pediatric Renal Transplant Cooperative Study.

To determine the current immunization recommendations of practicing pediatric nephrologists, a questionnaire was sent to the members of the North American Pediatric Renal Transplant Cooperative Society. Sixty-two percent of the centers responded. The results of the survey suggest that although consensus for approaching immunization does exist, recommendations do vary from center to center. Virtually all centers recommend standard vaccines [DTP, oral poliovirus (OPV), hepatitis B (Hep B), and Haemophilus influenzae B (Hib)] for their renal insufficiency and dialysis patients. Despite the fact that they are not infectious, standard killed vaccines (DTP, Hep B, Hib) are recommended less frequently for transplanted patients (86%) than their renal insufficiency (98%) and dialysis (near 100%) counterparts. Additionally, OPV and measles/mumps/rubella (MMR), both live viral vaccines, are rarely recommended post transplant. Almost 90% of centers recommend the use of influenza vaccine, while only 60% of centers recommend pneumococcal vaccine for children with renal disease. Over 70% of centers recommend the newly licensed varicella vaccine for patients on dialysis and those with renal insufficiency. Between 5% and 12% of centers recommend live viral vaccines, including OPV, MMR, and varicella vaccine, for immunosuppressed patients post renal transplant.

Child↗
PubMed1997

Recurrent vascular thrombosis in an adolescent transplant recipient.

Vascular thrombosis is one of the more difficult problems of pediatric renal transplantation; its etiology in multifactorial and, in most cases, it is irreversible. Vascular thrombosis accounts for 12.9% of graft failures in primary transplants in children and for 20% of graft failures in repeat transplants. Although it is seen most often in very young recipients and in recipients of kidneys from young donors, it can manifest in older children and adolescents as well. The peak incidence is seen in the first 48 h after transplantation; however, the event may be delayed until after the first week. When thrombosis occurs in an adolescent patients late in the course of transplantation, the pathogenesis is undetermined and immunosuppressive therapy is frequently implicated. This article describes a 19-yr-old patient with a three-antigen-matched cadaveric kidney who received cyclosporine and anti-thymocyte globulin for induction. Vascular thrombosis occurred after 7 d of initial good function. Eventually the graft was removed after attempts to re-establish vascularization failed. The patient received a second graft and despite an optimal six-antigen-match and different immunosuppression with tacrolimus, thrombosis recurred by the fifth postoperative day. The discussion that follows reviews the incidence and the factors implicated in the pathogenesis of this entity.

Adult↗
PubMed1997

Renal transplantation in children from 1987-1996: the 1996 Annual Report of the North American Pediatric Renal Transplant Cooperative Study.

The 1996 Annual Report of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) summarizes data voluntarily collected from 130 centers on 4329 children and adolescent patients who received renal transplants on or after January 1, 1987. This report updates information on transplants; data on dialysis and chronic renal insufficiency have, for the first time, been reported separately (in submission). The NAPRTCS registry shows that the majority of pediatric renal transplants are performed in children above 6 years of age (73%). The most frequent diagnoses include obstructive uropathy (16%), aplastic/hypoplastic/dysplastic kidneys (16%), and focal segmental glomerulosclerosis (12%). Pre-emptive transplantation was performed in 24% of patients. Triple drug maintenance therapy with prednisone, cyclosporine and azathioprine was used by >70% of all transplant recipients throughout 7 years of follow-up. Fifty-six per cent of transplant recipients were rehospitalized during months 1-5 (51% live donor (LD), 62% cadaver donor (CD)), with rejection and infection as the main causes. In the period 30-35 months post-transplant, 19-22% of patients (163 LD, 185 CD) were rehospitalized. The median time to the first rejection was 46 days for CD transplants and 377 days for LD grafts (p<.001). Six-year graft survival rates were 73% and 56% for LD grafts and CD grafts, respectively (p<.001). The overall growth deficit was constant over a period of 60 months. However, children transplanted under 5 years of age reduce their height deficit by about one-third compared to an increase in height deficit of up to 22% for older children. The NAPRTCS data analysis also demonstrates a delay in first rejection episodes in LD compared to CD transplants, and a steady improvement in CD graft survival over the past 5 years in pediatric transplant recipients.

Adolescent↗
PubMed1997

Pre-transplant blood transfusion and renal allograft outcome: a report of the North American Pediatric Renal Transplant Cooperative Study.

Data from the North American Pediatric Renal Transplant Cooperative Study were analyzed to determine the effect of pre-transplant blood transfusions on graft survival and acute rejection for pediatric renal transplant recipients. Between January 1, 1987 and November 11, 1995, 4015 renal transplants in children <18 years of age (2007 living donor, 2008 cadaver) were registered in the study. Recipients were grouped by number of pre-transplant blood transfusions (0, n=1171; 1-5, n=1796; >5, n=1048). The risks of graft failure and acute rejection were related to number of pre-transplant transfusions by proportional hazards regression analysis. Models were adjusted for recipient age, sex, race, induction therapy, prior dialysis, prior transplant, HLA-DR mismatching, and transplant year. Additionally, the living donor (LD) model was adjusted for the use of donor-specific blood transfusion, and the cadaver donor (CAD) model was adjusted for donor age and cold storage time. The risk of graft failure was increased in LD (p<0.001) and CAD (p=0.001) recipients who received >5 pre-transplant transfusions. There was no significant difference in the causes of graft loss between groups. The risk of a first acute rejection decreased in LD recipients who received 1-5 blood transfusions compared with 0 (p=0.04) or >5 (p=0.003) and in CAD recipients who received 1-5 compared with 0 (p=0.05). We conclude that multiple (>5) pre-transplant blood transfusions are a risk factor for graft failure in pediatric recipients and should be avoided. However, limited blood transfusions (1-5) are associated with a decreased risk of acute rejection. Our data show that for pediatric recipients the number of pre-transplant blood transfusions is an important factor in transplant outcome.

Blood Transfusion↗