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American Journal of Dermatopathology | 2003

Nephrogenic fibrosing dermopathy after liver transplantation successfully treated with plasmapheresis

Pedro W. Baron; Kenneth Cantos; Donald J. Hillebrand; Ke-Qin Hu; Okechukwu N. Ojogho; Sandra L. Nehlsen-Cannarella; Waldo Concepcion

Nephrogenic fibrosing dermopathy (NFD) is a recently described cutaneous fibrosing disorder associated with renal dysfunction. It appears similar to scleromyxedema but with some notable exceptions, including the lack of involvement of the face and absence of plasma cells on histology, systemic involvement, and paraproteinemia. Patients can present with thickened or edematous skin with indurated papules and plaques involving the extremities and the trunk. We report the first three cases of NFD after liver transplantation successfully treated with plasmapheresis. Two patients underwent liver transplantation for hepatitis C virus–induced cirrhosis and one for hepatitis B virus–induced cirrhosis. All the patients had encephalopathy, refractory ascites, and malnutrition prior to transplantation. Like those patients with NFD, all three of our patients had renal dysfunction and required hemodialysis before and after transplantation. Two were not dependent on dialysis at the time of diagnosis, however. These patients had excellent liver allograft function, but the other patient had allograft failure secondary to recurrent hepatitis C. Immunosuppression therapy consisted of basiliximab, mycophenolate mofetil, calcineurin inhibitor, and prednisone. The patients developed “woody” skin induration of the distal extremities, erythematous papules, and contractures at 1, 2, and 120 months after transplantation. Skin biopsies resembled NFD. No paraproteinemia was evident. One to three 5-day courses of plasmapheresis resulted in moderate to marked clinical improvement. The improvement of the kidney function in two of our patients did not appear to correlate with that of the skin disorder, because the kidney function was improving at the time the diagnosis of NFD was made. In conclusion, we report the first three cases of NFD after liver transplantation. Plasmapheresis was moderately successful in resolving the skin-indurated papules, severe skin induration, and associated joint contractures. Preliminary studies (unpublished data) show that decreasing plasma levels of transforming growth factor-&bgr;1 after plasmapheresis appear to correlate with the amelioration of this clinical condition.


Transplantation | 1997

Factors affecting survival after orthotopic liver transplantation in infants.

Thomas V. Cacciarelli; Carlos O. Esquivel; Dan H. Moore; Kenneth L. Cox; William E. Berquist; Waldo Concepcion; Gregory B. Hammer; Samuel So

The technical and medical management of small infants requiring orthotopic liver transplantation remains a challenge. The present study examined 117 orthotopic liver transplantations performed in 101 infants from <1 to 23 months of age between March 1988 and February 1995 to determine factors that influence patient and graft outcome. Factors analyzed included etiology of liver disease, recipient and donor age and weight, United Network for Organ Sharing (UNOS) status, retransplantation, ABO-compatibility, full-size (FS) versus reduced-size grafts, vascular thrombosis (VT), including hepatic artery and portal vein (PVT), and the presence of lymphoproliferative disease (LPD). UNOS status 1, fulminant hepatic failure, and the development of Epstein-Barr virus-associated LPD were each associated with 10-20% lower patient and graft survival rates. Of 101 infants, 11 (11%) developed LPD with an associated 36% mortality. VT occurred in 10 (9 hepatic artery and 1 portal vein) of 117 orthotopic liver transplantations (9%), all less than 1 year of age, and was associated with significantly poorer 1-year (50% vs. 85% no VT, P<0.01) and 5-year patient survival rates (50% vs. 83% no VT, P<0.01). One-year graft survival rates for FS grafts in recipients <12 months versus 12-23 months were 67% vs. 94% (P<0.01); the patient survival rate was also significantly lower in FS graft recipients <12 months (76% vs. 100%, P<0.05). Recipients <5 months of age had the worst survival rates: 1-year and 5-year patient survival rates were 65% and 46% for recipients 0-4 months (n=17) versus 82% and 82% for recipients 5-11 months (n=56), and 93% and 93% for recipients age 12-23 months (n=28; P<0.05). In summary, factors associated with reduced survival rates include recipient age <5 months, recipient age <12 months who received FS grafts, development of VT and donor weight <6 kg. There was a trend for UNOS status 1, fulminant hepatic failure, and presence of LPD to be associated with reduced survival rates.


Transplantation | 1994

NEUROLOGICAL COMPLICATIONS OF LIVER TRANSPLANTATION IN ADULT VERSUS PEDIATRIC PATIENTS

Fabrice Menegaux; Emmet B. Keeffe; Brian T. Andrews; Hiroto Egawa; Humberto Monge; Waldo Concepcion; Samuel So; Carlos O. Esquivel

Neurological complications are important contributors to morbidity and mortality after liver transplantation. We reviewed 391 patients who underwent 427 consecutive orthotopic liver transplantations to analyze the clinical features of patients who experienced one or more neurological complication (74 patients [19%]) and to compare postoperative neurological problems in adults versus children. Neurological complications were more frequent in adults (64 of 273 patients [23%]) than children (10 of 118 patients [8%]) (P < 0.01). The most common neurological complication was encephalopathy (59%), which ranged widely in severity and occurred with similar frequency in adults and children. Other common neurological complications were seizures (12 patients), brachial plexus and peripheral nerve injuries (16 patients, 15 of whom were adults), stroke (5 patients), and central nervous system infections (5 patients). In 27 patients, drug toxicity was the primary cause of neurological complications, all of which reversed with dosage reduction or discontinuation of drug. Cyclosporine and FK506, primarily during intravenous administration for induction of immunosuppression, accounted for 25 of 27 drug-induced neurological complications, which included encephalopathy, seizures, severe tremor, and severe headache. Despite a higher rate of neurological complications in adults, those in children were more severe and associated with a higher mortality rate. When compared with liver transplant recipients without neurological complications, patients with neurological complications had a higher posttransplant mortality rate (14% vs. 5% for adults, and 50% vs. 7% for children). In conclusion, neurological complications after liver transplantation are more common in adults, more severe and associated with a higher mortality rate in children, and associated with a higher mortality rate in both children and adults when compared with transplant recipients without neurological complications.


Transplantation | 1998

Experience with the piggyback technique without caval occlusion in adult orthotopic liver transplantation

Stephan Busque; Carlos O. Esquivel; Waldo Concepcion; Samuel So

BACKGROUND To assess the feasibility and outcome of a piggyback technique without caval occlusion or veno-venous bypass (VB), we retrospectively reviewed 131 consecutive adult orthotopic liver transplantation (OLT) performed in 129 patients between May 1993 and February 1995. Six were second transplants, and six were combined liver-kidney transplants. The piggyback technique was attempted in all cases. METHODS We were able to perform the piggyback technique in 98 OLTs (75%). The remaining 33 OLTs (25%) were converted to the standard technique; of these, 20 (15%) required VB. The reasons for conversion to the standard technique were: anatomical (22 transplants), severe portal hypertension requiring VB (8 transplants), tumor (1 transplant), and other reasons (2 transplants). Six retransplantations were performed (four piggyback, two standard). RESULTS There was no significant difference in age, United Network for Organ Sharing status, Childs classification, and diagnosis between the patients in whom piggyback was possible or not. The actuarial patient and graft survival at 1 year were similar between the piggyback group and the group of patients converted to standard technique (87/85% vs. 86/86%, respectively). No death was related to either technique. With piggyback, the average operative time was 8.6+/-1.9 hr, median amount of blood transfused intraoperatively was 2 U (33% did not require transfusion), and median intensive care unit and hospital stays were 3 and 11 days, respectively. With the piggyback technique, the mean preoperative and maximum postoperative serum creatinine levels were 1.4+/-1.0 and 1.8+/-1.5 mg/dl. CONCLUSION The piggyback technique without caval occlusion is possible in the majority of patients. It is safe and has reduced the use of VB to 15% of our adult OLTs. The piggyback technique avoids retrocaval dissection, facilitates retransplantation, and is associated with a short anhepatic phase, low blood product usage, and short intensive care unit stay.


American Journal of Transplantation | 2009

Steroid-Free Immunosuppression Since 1999: 129 Pediatric Renal Transplants with Sustained Graft and Patient Benefits

Li Li; Anthony Chang; Maarten Naesens; Neeraja Kambham; Janie Waskerwitz; J. P. Martin; Cynthia Wong; Steven R. Alexander; Paul C. Grimm; Waldo Concepcion; Oscar Salvatierra; Minnie M. Sarwal

Despite early promising patient and graft outcomes with steroid‐free (SF) immunosuppression in pediatric kidney transplant recipients, data on long‐term safety and efficacy results are lacking. We present our single‐center experience with 129 consecutive pediatric kidney transplant recipients on SF immunosuppression, with a mean follow‐up of 5 years. Outcomes are compared against a matched cohort of 57 concurrent recipients treated with steroid‐based (SB) immunosuppression. In the SF group, 87% of kidney recipients with functioning grafts remain corticosteroid‐free. Actual intent‐to‐treat SF (ITT‐SF) and still‐on‐protocol SF patient survivals are 96% and 96%, respectively, actual graft survivals for both groups are 93% and 96%, respectively and actual death‐censored graft survivals for both groups are 97% and 99%, respectively. Unprecedented catch‐up growth is observed in SF recipients below 12 years of age. Continued low rates of acute rejection, posttransplant diabetes mellitus (PTDM), hypertension and hyperlipidemia are seen in SF patients, with sustained benefits for graft function. In conclusion, extended enrollment and longer experience with SF immunosuppression for renal transplantation in low‐risk children confirms protocol safety, continued benefits for growth and graft function, low acute rejection rates and reduced cardiovascular morbidity.


Transplantation | 2004

Prospective, randomized trial of the effect of antibody induction in simultaneous pancreas and kidney transplantation: Three-year results

George W. Burke; Dixon B. Kaufman; J. Michael Millis; A. Osama Gaber; Christopher P. Johnson; David E. R. Sutherland; Jeffrey D. Punch; Barry D. Kahan; Eugene J. Schweitzer; Alan N. Langnas; James D. Perkins; John D. Scandling; Waldo Concepcion; Mark D. Stegall; James A. Schulak; Paul F. Gores; Enrico Benedetti; Gabriel M. Danovitch; Alice K. Henning; Marilyn R. Bartucci; Sarah Smith; William E. Fitzsimmons

Background. Historically, antibody induction has been used because of the higher immunologic risk of graft loss or rejection observed in simultaneous pancreas and kidney (SPK) transplantation compared with kidney transplantation alone. This trial was designed to assess the effect of antibody induction in SPK transplant recipients receiving tacrolimus, mycophenolate mofetil, and corticosteroids. Induction agents included T-cell–depleting and interleukin-2 receptor antibodies. Methods. A total of 174 SPK transplant recipients were enrolled in a prospective, open-label, multi-center study. They were randomized to induction (n=87) or non-induction (n=87) groups and followed for 3 years. Results. At 3 years, actual patient (94.3% and 89.7%) and pancreas (75.9% and 75.9%) survivals were similar between the induction and non-induction groups, respectively. Actual kidney survival was similar at 1 and 2 years, but at 3 years, it was significantly better in the induction group compared with the non-induction group (92% vs. 81.6%; P =0.04). At 3 years, median serum creatinine and hemoglobin A1C were similar between the induction and non-induction groups (1.35 mg/dL and 1.20 mg/dL, 5.4% and 5.5%, respectively). Three-year cumulative incidence of biopsy-confirmed, treated acute kidney rejection in the induction and non-induction groups was 19.5% and 27.5% (P =0.14), respectively, with odds 4.6 times greater in African Americans regardless of treatment (P =0.004). Significantly higher rates of cytomegalovirus (CMV) viremia and CMV syndrome occurred in those receiving T-cell–depleting antibody induction (36.1%) when compared with those receiving anti–interleukin-2 receptor antibodies (2%) and non-induction (8.1%) (P <0.0001). Conclusions. Tacrolimus, mycophenolate mofetil, and corticosteroids resulted in excellent safety and efficacy in SPK transplant recipients. Actual 3-year kidney survival was significantly better in the induction group; however, CMV viremia and CMV syndrome rates were significantly higher in the T-cell–depleting antibody group. African Americans demonstrated a significantly greater risk of acute rejection despite antibody induction. Decisions regarding the use of induction therapy must weigh the risk of kidney graft loss or rejection against the risk of infection.


Pediatric Transplantation | 1999

Long-term outcomes in pediatric liver recipients: Comparison between cyclosporin A and tacrolimus

Sean Cao; Kenneth L. Cox; William E. Berquist; Michihiro Hayashi; Waldo Concepcion; G. B. Hammes; O. K. Ojogho; Samuel So; M. Frerker; Ricardo O. Castillo; Humberto Monge; Carlos O. Esquivel

Cao S, Cox KL, Berquist W, Hayashi M, Concepcion W, Hammes GB, Ojogho OK, So SKS, Frerker M, Castillo RO, Monge H, Esquivel CO. Long‐term outcomes in pediatric liver recipients: Comparison between cyclosporin A and tacrolimus. Pediatr Transplantation 1999: 3: 22–26.


American Journal of Transplantation | 2007

The evolution of nonimmune histological injury and its clinical relevance in adult-sized kidney grafts in pediatric recipients

Maarten Naesens; Neeraja Kambham; Waldo Concepcion; Oscar Salvatierra; Minnie M. Sarwal

To describe the evolution, risk factors and impact of nonimmune histological injury after pediatric kidney transplantation, we analyzed 245 renal allograft protocol biopsies taken regularly from the time of transplantation to 2 years thereafter in 81 consecutive rejection‐free pediatric recipients of an adult‐sized kidney. Isometric tubular vacuolization was present early after transplantation was not progressive, and was associated with higher tacrolimus pre‐dose trough levels. Chronic tubulo‐interstitial damage and tubular microcalcifications were already noted at 3 months, were progressive and had a greater association with small recipient size, male donor gender, higher donor age and female recipient gender, but not with tacrolimus exposure. Renal function assessment showed that older recipients had a significant increase in absolute glomerular filtration rate with time after transplantation, which differed from small recipients who showed no increase. It is concluded that progressive, functionally relevant, nonimmune injury is detected early after adult‐sized kidney transplantation in pediatric recipients. Renal graft ischemia associated with the donor‐recipient size discrepancy appears to be a greater risk factor for this chronic histological injury, suggesting that the exploration of additional therapeutic approaches to increase allograft perfusion could further extend the graft survival benefit of adult‐sized kidneys transplanted into small children.


Transplant Infectious Disease | 2011

West Nile virus encephalitis acquired via liver transplantation and clinical response to intravenous immunoglobulin: case report and review of the literature

Chanu Rhee; E.F. Eaton; Waldo Concepcion; Brian G. Blackburn

C. Rhee, E.F. Eaton, W. Concepcion, B.G. Blackburn. West Nile virus encephalitis acquired via liver transplantation and clinical response to intravenous immunoglobulin: case report and review of the literature.
Transpl Infect Dis 2011: 13: 312–317. All rights reserved


Transplantation | 1998

Posttransplant lymphoproliferative disorders and gastrointestinal manifestations of Epstein-Barr virus infection in children following liver transplantation

Sean Cao; Kenneth L. Cox; Carlos O. Esquivel; William E. Berquist; Waldo Concepcion; Okechukwu N. Ojogho; Humberto Monge; Sheri M. Krams; Olivia M. Martinez; Samuel So

BACKGROUND Epstein-Barr virus (EBV) infection is common after liver transplantation in children and is associated with the risk of posttransplant lymphoproliferative disorders (PTLD). METHODS This retrospective study examined the frequency of gastrointestinal (GI) symptoms and the risk of PTLD in pediatric liver recipients who developed symptomatic EBV infection. We reviewed 172 children who received orthotopic liver transplants between March 1988 to December 1994. Twenty-two cases were retransplants. The mean age at transplantation was 3.7 years (range, 0.1-17 years). The immunosuppressive regimens consisted of induction therapy with Minnesota antilymphocyte globulin/antithymocyte globulin/OKT3 in most cases and maintenance therapy with prednisone and either cyclosporine or tacrolimus (FK506). RESULTS After 1 year of minimum follow-up, 54 of 172 patients had symptomatic EBV infections (confirmed by serology, histology, or whole blood polymerase chain reaction. At the time of infection, 38.5% (21/54) had either diarrhea or GI bleeding or both. PTLD developed in 11 patients (6.4%). The incidence of PTLD was 42.9% (9/21) when GI bleeding or diarrhea was associated with EBV infections, compared with 6.1% (2/33) when EBV infection was not associated with GI symptoms. Seven of 10 (70%) patients with GI bleeding and 2 of 11 (18.2%) with diarrhea developed PTLD. Of seven patients examined by endoscopy for GI bleeding, two had biopsy-proven PTLD of the GI tract, whereas one of two patients examined by endoscopy for diarrhea had biopsy-proven PTLD. DISCUSSION In summary, a high incidence of PTLD was found in patients who developed GI bleeding or diarrhea associated with EBV infection after pediatric liver transplantation. In these patients, endoscopy and biopsy may lead to early diagnosis of PTLD.

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Okechukwu N. Ojogho

Loma Linda University Medical Center

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Paul Nakazato

California Pacific Medical Center

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Pedro W. Baron

Loma Linda University Medical Center

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