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J Reyes

Publications and source records attributed to J Reyes.

At least 19 recordsLinked to original sources
PubMed1995

Incidence and risk factors associated with the development of cytomegalovirus disease after intestinal transplantation.

From May 1990 to March 1993, 38 patients (21 adults and 17 children) received 40 allografts that included the small bowel (14 isolated small bowel, 21 small bowel and liver, and 5 multivisceral transplantations). Fifteen patients (39%) had 26 episodes of CMV disease: 7 with one episode, 6 with two, and 1 each with three and four. CMV enteritis accounted for 21 (81%) of the episodes, hepatitis and pneumonitis for 2 each, and a viral syndrome for 1. Cox's proportional hazards univariate and multivariate analyses showed that significant first-episode risk factors were: CMV seropositive donors for negative recipients (relative risk [RR], 3.86; P = 0.02), the average daily plasma trough level of tacrolimus (RR, 2.15; P = 0.04), and total amount of steroid boluses (RR, 2.90; P = 0.02). CMV disease recurrence factors were: CMV seronegative recipients (RR, 8.60; P = 0.02) and total amount of steroid bolus pulses (RR, 12.39; P = 0.004). Because long courses of ganciclovir prophylaxis could not prevent the development of CMV disease, avoidance of CMV seropositive grafts in seronegative recipients and new strategies to prevent heavy immunosuppression without the penalty of rejection will be necessary to ameliorate this problem in intestinal transplant recipients.

Adolescent↗
PubMed1995

Weaning of immunosuppression in long-term liver transplant recipients.

Seventy-two long-surviving liver transplant recipients were evaluated prospectively, including a baseline allograft biopsy for weaning off of immunosuppression. Thirteen were removed from candidacy because of chronic rejection (n = 4), hepatitis (n = 2), patient anxiety (n = 5), or lack of cooperation by the local physician (n = 2). The other 59, aged 12-68 years, had stepwise drug weaning with weekly or biweekly monitoring of liver function tests. Their original diagnoses were PBC (n = 9), HCC (n = 1), Wilson's disease (n = 4), hepatitides (n = 15), Laennec's cirrhosis (n = 1), biliary atresia (n = 16), cystic fibrosis (n = 1), hemochromatosis (n = 1), hepatic trauma (n = 1), alpha-1-antitrypsin deficiency (n = 9), and secondary biliary cirrhosis (n = 1). Most of the patients had complications of long-term immunosuppression, of which the most significant were renal dysfunction (n = 8), squamous cell carcinoma (n = 2) or verruca vulgaris of skin (n = 9), osteoporosis and/or arthritis (n = 12), obesity (n = 3), hypertension (n = 11), and opportunistic infections (n = 2). When azathioprine was a third drug, it was stopped first. Otherwise, weaning began with prednisone, using the results of corticotropin stimulation testing as a guide. If adrenal insufficiency was diagnosed, patients reduced to < 5 mg/day prednisone were considered off of steroids. The baseline agents (azathioprine, cyclosporine, or FK506) were then gradually reduced in monthly decrements. Complete weaning was accomplished in 16 patients (27.1%) with 3-19 months drug-free follow-up, is progressing in 28 (47.4%), and failed in 15 (25.4%) without graft losses or demonstrable loss of graft function from the rejections. This and our previous experience with self-weaned and other patients off of immunosuppression indicate that a significant percentage of appropriately selected long-surviving liver recipients can unknowingly achieve drug-free graft acceptance. Such attempts should not be contemplated until 5-10 years posttransplantation and then only with careful case selection, close monitoring, and prompt reinstitution of immunosuppression when necessary.

Adolescent↗
PubMed1995

Abdominal multivisceral transplantation.

Under FK506-based immunosuppression, 13 abdominal multivisceral transplantations were performed in 6 children and 7 adults. Of the 13 recipients, 7 (53.8%) are alive and well with functioning grafts after 9 to 31 months. Six recipients died: three from PTLD, one from rejection, one from sepsis, and one from respiratory failure. In addition to rejection, postoperative complications occurring in more than isolated cases included PTLD (n = 6), abdominal abscess formation (n = 5), pancreatitis (n = 3), and ampullary dysfunction (n = 2). In addition, infection by enteric microorganisms was common during the early postoperative period. Currently, all 7 survivors are on an oral diet and have normal liver function. Two recipients (one insulin-dependent) require antidiabetes treatment, in one case following distal pancreatectomy and in the other after two episodes of pancreatic rejection. Thus, abdominal multivisceral transplantation is a difficult but feasible operation that demands complex and prolonged posttransplantation management. It is not yet ready for application and awaits a better strategy of immune modulation.

Abdomen↗
PubMed1995

The association of Epstein-Barr virus with smooth-muscle tumors occurring after organ transplantation.

BACKGROUND: Epstein-Barr virus (EBV) has been associated with nasopharyngeal carcinoma, some lymphomas, and lymphoproliferative disease after organ transplantation. Many lymphoproliferative tumors that occur after transplantation are clonal, a property that classifies them as neoplastic. Clonality can be determined by analysis of the extrachromosomal circular DNA episomes produced by EBV infection. METHODS: We describe three young children in whom smooth-muscle tumors developed 18 months to 5 1/2 years after liver transplantation with immunosuppression. We examined the tumors by microscopy and with immunohistochemical studies and molecular genetic analyses of the EBV DNA: RESULTS: The tumors were composed of spindle cells with smooth-muscle features and resembled those described in patients with the acquired immunodeficiency syndrome. Immunohistochemical analysis was negative for EBV latent membrane protein and EBV receptor (CD21), but positive for EBV nuclear antigen 2. In situ hybridization revealed nuclear EBV sequences, and molecular genetic analysis showed the EBV genome to be clonal in all three patients. CONCLUSIONS: Smooth-muscle tumors that developed after organ transplantation contained clonal EBV, suggesting that the virus has a role in the development of these neoplastic lesions.

Colonic Neoplasms↗
PubMed1995

Arterioportal fistula following liver biopsy. Three cases occurring in liver transplant recipients.

Although liver biopsy is a very useful procedure used frequently in the diagnosis and management of liver dysfunction occurring after orthotopic liver transplantation, complications can occur with its use. An unusual complication of arterioportal fistula is reported here. Based upon this small series of an unusual event and the knowledge that the posttransplant liver may be more hypervascular than prior to OLTx and that it is uniquely susceptible to hepatic infarction and abscess formation, any attempt at fistula closure should be considered carefully prior to initiating the therapy (15). Unless a serious complication occurs [such as a transient biliary obstruction due to hemobilia as occurred in case 2, portal hypertension as also occurred in case 2, or systemic sepsis or other symptoms develop related directly to the fistula], simple observation may be the best choice of action. Should therapy be required, hepatic arterial embolization should be reserved for adults with intrahepatic fistulas. Primary surgical closure of intrahepatic fistula should be reserved for cases of extrahepatic fistula.

Adult↗
PubMed1995

Orthotopic liver transplantation for ornithine transcarbamylase deficiency with hyperammonemic encephalopathy.

Ornithine transcarbamylase (OTC) deficiency is an X chromosome-linked disorder causing hyperammonemic encephalopathy with a very poor prognosis. We describe here two patients with OTC deficiency, one a late on-set female patient (case 1) and the other a neonatal-onset male patient (case 2), who were successfully treated with orthotopic liver transplantation (OLTx). The OTC activity in the excised liver was 10% and 0% of control, respectively. Hyperammonemic encephalopathy was controlled with medical therapy in case 1 until the of 5 years, but the complicated course in case 2 in which hyperammonemia required peritoneal dialysis and hemodialysis in the neonatal period necessitated OLTx with a reduced-size liver at the age of 80 days. Both patients had restoration of serum ammonia level to normal in 2 and 3 days after liver replacement, and both patients have normal neurological and developmental status after 2 and 0.5 years of postoperative follow-up. These cases illustrate not only the metabolic cure of this disorder, but also the need to preserve neurological integrity by aggressive medical management of the hyperammonemia preoperatively and early surgical intervention when indicated, even if this is required very early in life.

Ammonia↗
PubMed1995

Endorectal pull-through of transplanted colon as part of intestinal transplantation.

BACKGROUND: Two children with life-threatening disorders underwent intestinal transplantation; one multivisceral transplantation excluding the liver, and the second transplantation of the liver, small bowel, and colon. METHODS: Involvement of the native rectum necessitated resection and replacement with the transplanted allograft. To prevent a permanent colostomy, a pull-through of the allograft colon was performed. RESULTS: Both patients had a stormy early postoperative course, mainly because of the complexities of intestinal transplantation, but with eventual recovery, including improvement of rectal function. CONCLUSIONS: These are the first two known cases in which a transplanted large intestine was used for a pull-through procedure.

Colon↗
PubMed1995

Pathology of intestinal transplantation in children.

The role of mucosal biopsy in the monitoring of pediatric intestinal allografts is analyzed. We performed a retrospective review of all biopsy, resection, and autopsy material from 22 bowel allografts in 21 patients, followed from 6 months to 3 1/4 years and treated on an immuno-suppressive regimen based on FK 506 (Tacrolimus). There were 579 biopsies, of which 35 were stomal, with two to three fragments taken at each biopsy. There were three explanted bowels and three autopsies. Stomal biopsies proved to be inappropriate for monitoring. Biopsies with three to five pieces of tissue per site, under endoscopic direction, provided the most information. Early cellular infiltrate with lymphoid activation in the absence of epithelial apoptotic figures was not considered sufficient to diagnose rejection although preceded it in most instances. At least two apoptotic figures in a gland or several single apoptotic cells in the presence of a lymphoid infiltrate with activated lymphoid follicles and prominent endothelium correlate best with clinical rejection and response to antirejection measures. Epstein-Barr viral disease is common in this population, and early, late, and noncontiguous bowel involvement can be subtle and difficult to distinguish from rejection, though without the apoptosis. Epstein-Barr virus in situ probes are essential to make the differential diagnosis and the two conditions may co-exist. Mucosal biopsy monitoring appears to be of clinical utility and is part of a program that involves clinical, endoscopic, microbiological, and morphologic assessment.

Adolescent↗
PubMed1995

Outcome analysis of 71 clinical intestinal transplantations.

OBJECTIVE: The aim of the study was to determine risk factors associated with graft failure and mortality after transplantation of the intestine alone or as part of an organ complex. SUMMARY BACKGROUND DATA: Even with modern immunosuppressive therapies, clinical intestinal transplantation remains a difficult and unreliable procedure. Causes for this and solutions are needed. METHODS: Between May 1990 and February 1995, 71 intestinal transplantations were performed in 66 patients using tacrolimus and low-dose steroids. The first 63 patients, all but one treated 1 to 5 years ago, received either isolated grafts (n = 22), liver and intestinal grafts (n = 30), or multivisceral grafts (n = 11). Three more recipients of allografts who recently underwent surgery and one undergoing retransplantation were given unaltered donor bone marrow cells perioperatively as a biologic adjuvant. RESULTS: Of the first 63 recipients, 32 are alive: 28 have functioning primary grafts and 4 have resumed total parenteral nutrition after graft enterectomy. Thirty-five primary grafts were lost to technical and management errors (n = 10), rejection (n = 6), and infection (n = 19). Regression analysis revealed that duration of surgery, positive donor cytomegalovirus (CMV) serology, inclusion of graft colon, OKT3 use, steroid recycle, and high tacrolimus blood levels contributed to graft loss. All four intestine and bone marrow recipients are alive for 2-3 months without evidence of graft-versus-host disease. CONCLUSION: To improve outcome after intestinal transplantation with previous management protocols, it will be necessary to avoid predictably difficult patients, CMV seropositive donors, and inclusion of the graft colon. Bone marrow transplantation may further improve outcome by ameliorating the biologic barriers of rejection and infection and allowing less restrictive selection criteria.

Adult↗
PubMed1995

Effect of supplemental yeast culture in sow gestation and lactation diets on apparent nutrient digestibilities and reproductive performance through one reproductive cycle.

Ninety-six crossbred sows and gilts were used to study the effect of yeast culture (Diamond V. Mills, Cedar Rapids, IA) on apparent nutrient digestibilities and reproductive performance from d 60 of gestation through d 21 of lactation. Sows were allotted to treatment groups based on parity and BW. Four dietary treatments were made by substituting 0, .5, 1.0, or 2.0% yeast culture for wheat middlings in the basal gestation and lactation diets. During gestation, sows were fed 2.15 kg/d of a 12.5% CP corn-soybean meal diet containing 25.0% alfalfa meal that provided 6.39 Mcal of ME/d. During lactation, sows were fed a 13.5% CP corn-soybean meal diet containing 12.5% alfalfa meal (3.16 Mcal of ME/kg) to appetite daily. Yeast culture supplementation did not affect (P > .3 to .9) the apparent digestibilities of DM, energy, CP, ether extract, ADF, and NDF in gestation (d 90 to 97) or lactation (d 14 to 21), sow weights on d 107 of gestation and d 1 and 21 of lactation, lactation feed intake, or days from weaning to first estrus compared to control sows. Also, yeast culture treatment had no effect (P > .3 to .5) on number of live pigs/litter at birth and d 21 or total litter weight on d 21. In conclusion, supplemental yeast culture in gestation and lactation diets containing alfalfa meal did not affect apparent nutrient digestibilities and reproductive performance criteria through one reproductive cycle.

Animals↗
PubMed1995

Clinical features of nosocomial rotavirus infection in pediatric liver transplant recipients.

A retrospective survey of nosocomial rotavirus infection in pediatric liver transplant recipients was performed. Immunocompetent children with nosocomial infections served as controls. Co-pathogens were not identified. A total of 12 transplant cases and 12 controls could be evaluated. New onset vomiting occurred in 7/8 cases and 6/11 controls lasting an average of 2.8 days per case and 0.8 days per control (p < .05). New onset fever (>38 degrees C) was noted in 8/12 cases and 9/12 controls. New onset occult blood was noted in 7/11 cases and 1/12 controls (p < .01). A concomitant rise and fall in transaminases was noted in 5/12 transplant recipients. Eleven of the 12 were maintained on constant or increased immunosuppression doses without the development of fulminant disease. The presence of increased days of vomiting and occult blood in stools suggests that rotavirus causes a more invasive process in the intestinal mucosa of transplant recipients compared to immunocompetent children. However, the process remains self-limited despite the use of potent immunosuppressives.

Cross Infection↗
PubMed1995

FK506 (tacrolimus) in the treatment of steroid-resistant acute graft-versus-host disease in children undergoing bone marrow transplantation.

Steroid-resistant graft-versus-host disease (GVHD) is an often lethal complication of bone marrow transplantation (BMT). FK506 (tacrolimus) is a new potent immunosuppressant which has been shown to be superior to conventional immunosuppression in the prevention and treatment of graft rejection in recipients of solid organ transplants. To determine whether FK506 is effective in the treatment of steroid-resistant acute GVHD, 6 children with biopsy-proven severe GVHD were studied. FK506 was administered as intravenous or oral therapy and the dose was adjusted to achieve serum levels between 0.5 and 1.0 microgram/ml by ELISA. Steroid doses were tapered based on clinical grading in each organ. Within 1-2 days, improvement occurred in skin and gut in all patients, and in liver in 3 patients. Toxicity attributable to FK506 was similar to that described in solid organ transplant patients and included neurotoxicity, nephrotoxicity and gastrointestinal effects. While FK506 is effective in the treatment of steroid-resistant acute GVHD, toxicity may limit its use. Further studies evaluating FK506 as GVHD prophylaxis and treatment of less advanced GVHD are needed.

Adolescent↗
PubMed1994

Small intestinal transplantation in humans with or without the colon.

Under FK506-based immunosuppression, 16 cadaveric small bowel transplantations were performed in 15 recipients with (n = 5) or without (n = 11) the large bowel. Twelve (80%) patients are alive after 1.5 to 19 months, 11 bearing their grafts, of which 4 include colon. The actuarial one-year patient and graft survivals are 87.5% and 65.9%, respectively. Five grafts were lost to acute (n = 4) or chronic (n = 1) rejection, and 3 of these patients subsequently died after 376, 440, and 776 days total survival. Six recipients developed severe CMV infection that was strongly associated with seronegative status preoperatively and receipt of grafts from CMV positive donors; 3 died, and the other 3 required prolonged hospitalization. Currently, 9 patients are free from TPN 1-18 months postoperatively, 2 require partial TPN, and one has returned to TPN after graft removal. The results show the feasibility of small bowel transplantation but emphasize the difficulty of managing these recipients not only early but long after their operation.

Adult↗