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Biomedical subjects

W E Berquist

Publications and source records attributed to W E Berquist.

At least 19 recordsLinked to original sources
PubMed2006

Adolescent non-adherence: prevalence and consequences in liver transplant recipients.

Few studies have examined the prevalence, demographic variables and adverse consequences associated with non-adherence to immunosuppressive therapy in the adolescent liver transplant population. Our hypothesis is that a significant proportion of adolescent liver transplant recipients exhibit non-adherence to medical regimens and that certain demographic and medical condition-related characteristics can be identified as potential predictors of non-adherent behavior. Furthermore, non-adherence leads to a greater incidence of morbidity and mortality in this population as compared with the adherent subset of adolescent patients. We reviewed the charts of 97 patients from 1987 to 2002 who by December of 2002 had survived at least 1 yr post-transplant and were followed by the Pediatric Liver Transplant Service at any point during their adolescent period (ages of 12-21). Non-adherence was defined as documentation of a report of non-adherence by a patient, parent or healthcare provider that was recorded in the patient's legal medical record. Descriptive statistics were used to determine the prevalence, demographic variables and adverse outcomes associated with non-adherence to immunosuppressive therapy. Categorical variables were analyzed using the chi-square test or the Fisher exact probability test. The unpaired Student's t-test was used to analyze the continuous variable of age at transplant. Using the inclusion criteria, a total of 97 patients represented the study sample of whom 37 subjects (38.1%) were defined as non-adherent and 60 (61.8%) were adherent. Non-adherent subjects were more likely to be female, older (>18 yr) and from a single-parent household. There was no significant difference in immunosuppressive regimen between non-adherent and adherent patients. Non-adherence was significantly (p<0.025) associated with lower socioeconomic status (SES), older age at transplant (p<0.005, 95% CI: -5.5 to -.99, Student's t-test) and episodes of late acute rejection (p<.001). Non-adherence was also significantly associated with re-transplantation and death secondary to chronic rejection by the Fisher exact test (p<0.006 and p<0.05, respectively). Non-adherence to immunosuppressive therapy is a prevalent problem that is correlated with certain demographic and medical condition-related risk factors and more frequent adverse consequences in the adolescent liver transplant population. The greater incidence of late acute rejection, death and re-transplantation owing to chronic rejection in non-adherent patients suggests that non-adherence is significantly associated with an increased risk of morbidity and mortality. Further investigation to identify patients at greatest risk for non-adherence is necessary to design the most effective intervention to increase patient survival and well being.

Adolescent↗
PubMed1999

Paediatric liver transplantation: indications, timing and medical complications.

Newer surgical techniques and immunosuppressive therapies have resulted in paediatric liver transplantation being available for most children with end-stage liver disease and has resulted in a greater than 80% 5-year survival rate. The most common indications for paediatric liver transplantation are biliary atresia (43%), metabolic disease (13%) and acute hepatic necrosis (11%). For approximately 75% of children with acute hepatic failure, the cause is unknown. Timing of liver transplantation not only affects survival rate, but may influence neurodevelopmental outcome. Fortunately, numerous types of donors, such as reduced-sized, living related or unrelated and blood-type mismatched, have reduced the mortality of children who are waiting for liver transplantation. However, the mortality and morbidity before and after liver transplantation remain high for children who have fulminant hepatic failure or are less than 5 months of age at the time of transplantation. The principle medical complications after liver transplantation are rejection and infection. Although use of newer immunosuppressive regimens has reduced the rate of rejection, Epstein-Barr virus infection with associated lymphoproliferative disorder remains the principle cause for morbidity and mortality after the initial 3 months post-liver transplant.

Adolescent↗
PubMed1998

Liver transplantation at Stanford University Medical Center.

Because of the unique demographics of our patient population, we have had the opportunity to dedicate further studies of the management of hepatitis B and hepatitis C. We have experienced a very low HBV recurrence rate with the use of HBIG in patients transplanted for hepatitis B. Investigations, including the use of new antiviral agents, and the development of approaches to minimize or abrogate disease recurrence such as lower levels of immunosuppression are ongoing. Using a standardized approach to the proper evaluation and selection of patients for liver transplantation with alcoholic liver disease or other liver diseases with coexistent alcohol abuse, we report favorable long-term results in these patients. We have reviewed our results and our approach to the management of EBV and posttransplant lymphoproliferative disorder. There is a firm commitment in our laboratories and outpatient clinics to the investigation of disease prevention, reliable detection and screening methods, and treatment modalities for EBV-related disease. We have addressed specific technical considerations to pediatric liver transplant and have discussed unique aspects of postoperative management in these patients. One-third of the transplants performed at Stanford are in children, 42% of whom are less than one year old. Results with our pediatric transplant recipients compare favorably with those of our adult recipients with patient and graft survival rates approaching 90% at one year and exceeding 80% at 46 months for both groups. As a response to the limited organ supply, we have extended our criteria for suitable donors. Most notably, we have utilized older donors and grafts with significant microsteatosis and have observed good results with these grafts as long as ischemia time is minimized. We have also successfully used reduced size grafts for our pediatric patients with good results and are continuing to expand the use of living-related partial grafts and split allografts.

Adolescent↗
PubMed1997

Cholic acid synthesis is reduced in pediatric liver recipients during graft dysfunction due to ischemic injury and allograft rejection.

BACKGROUND: Bile acids are synthesized and secreted by the liver. During liver failure and hepatic dysfunction, a marked reduction of bile acid synthesis has been shown. The purpose of this study was to determine whether the biliary bile acid pattern was affected by preservation injury and rejection and whether it was a reliable marker for graft function in pediatric liver recipients after liver transplantation. METHODS: We prospectively measured the biliary bile acid pattern in 126 serial bile samples obtained from 15 consecutive pediatric liver recipients by reversed phase high pressure liquid chromatography and correlated our results with clinical findings: preservation injury, no rejection, rejection, or infection. RESULTS: There was a significant change of the bile acid pattern during the first 3 days after transplant. Total biliary bile acids, cholic acid (CA), and CA/chenodeoxycholic acid (CDCA) ratio increased in 12 of 15 patients with mild preservation injury. These changes of the bile acid pattern were markedly delayed in patients with severe preservation injury. During 16 rejection episodes, total biliary bile acid, CA, and CA/CDCA ratio decreased significantly, but returned to normal after successful treatment of rejection. Bacterial infection, observed in nine children, and cyclosporine toxicity, observed in three children, seemed to have no affect on the biliary bile acids. CONCLUSIONS: Liver cell damage as a result of preservation injury or rejection leads to a reduction of biliary CA, resulting in a decrease of total biliary bile acids and the CA/CDCA ratio in pediatric liver recipients. This might be caused by a diminished secretion of bile acids and by a decreased synthesis of bile acids.

Adolescent↗
PubMed1997

Factors affecting survival after orthotopic liver transplantation in infants.

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.

Aging↗
PubMed1996

Continuous venovenous hemofiltration with dialysis in combination with total hepatectomy and portocaval shunting. Bridge to liver transplantation.

Children who experience acute liver failure following liver transplantation will have multiple organ failure and a high rate of mortality unless emergency retransplantation can be performed. Transplant hepatectomy with portocaval shunting has been described as a bridge to transplantation in the most severe cases, as well as in patients with fulminant hepatic failure at high risk for mortality who have not undergone liver transplantation. Patients with multiple organ failure who have undergone hepatectomy require renal replacement therapy. Continuous hemofiltration may be used in patients with fulminant hepatic failure to facilitate fluid removal and circulatory and metabolic balance. We used continuous venovenous hemofiltration with dialysis following hepatectomy with portocaval shunting in a patient who remained anhepatic for 66 hr in order to achieve circulatory and metabolic homeostasis as well as stable neurologic function prior to successful retransplantation.

Child, Preschool↗
PubMed1996

Oral tacrolimus (FK506) induction therapy in pediatric orthotopic liver transplantation.

We have adopted the use of an oral tacrolimus induction protocol in pediatric liver transplantation since the commercial release of tacrolimus in 1994. In this study we analyzed the efficacy of oral tacrolimus induction therapy in 17 consecutive transplants (15 patients) performed between 6/94 and 2/95 and 4 additional patients who were retransplanted between 11/93-5/94 and received compassionate oral tacrolimus induction. Sixteen transplants were treated with oral tacrolimus induction only; 5 transplants, oral tacrolimus + ATGAM/OKT3 induction. The protocol consisted of 0.2 mg/kg of tacrolimus orally on the first postoperative day with a corticosteroid taper. Oral tacrolimus was started at day 1-8 in the 5 patients receiving ATGAM/OKT3 induction. Dosages were adjusted over time to maintain a whole-blood trough level of 12-15 ng/ml at 0-1 month, 10-12 ng/ml at 1-3 months, and 5-10 ng/ml after 3 months. The incidence of acute rejection was 50% (8/16) in children on oral tacrolimus induction alone and 80% (4/5) in the tacrolimus + ATGAM/OKT3 group. Epstein-Barr virus infection occurred in 6 of 19 children (32%), with no child developing lymphoproliferative disorder. No adverse effect on renal function was noted. Serum fasting glucose was stable over time while a trend was noted in decreasing serum cholesterol levels at 6 months. Antihypertensive medication was required in 4 of 19 children (21%) posttransplantation. Corticosteroids were withdrawn in 11% (2/19) of patients. Actuarial 1-year patient and graft survivals were 95% and 86%, respectively. The use of oral tacrolimus induction therapy was associated with excellent survival and a low incidence of complications.

Administration, Oral↗
PubMed1995

An increased incidence of Epstein-Barr virus infection and lymphoproliferative disorder in young children on FK506 after liver transplantation.

The incidence of Epstein-Barr virus (EBV) infection and lymphoproliferative disorder (LPD) was determined in a pediatric liver transplant population consisting of 51 children treated with FK506 and 91 treated with cyclosporine. The incidence of symptomatic EBV infection was 21.9% (23 of 105 cases) in children < 5 yr old and 10.8% (4 of 37 cases) in children 5 to 17 yr old as compared with 2.7% (9 of 323 cases) in adults (P < 0.0001). In the under 5 yr old group on cyclosporine, the incidences of EBV infection and LPD were 9 of 68 (13.2%) and 2 of 68 children, (2.9%), respectively. In contrast, in children under 5 yr old group on FK506, the incidences of EBV infection and LPD in the FK506 group were 14 of 37 (37.8%) and 7 of 37 children (18.9%), respectively. The difference between these two groups was statistically significant (P < 0.02). There were no cases of LPD in the 5-17 yr-old children on either cyclosporine (n = 23) or FK506 (n = 14). The incidence of EBV infections in the 5 to 17 yr age group, 17.4% on cyclosporine and 0% on FK506, was less than for the younger children on FK506 (37.8%). A total of 39% (9 of 23) of children under 5 yr old who had symptomatic EBV infections developed LPD, and 44% (4 of 9) with LPD died. The higher incidence of EBV infections and LPD in the younger children treated with FK506 was probably related to a greater intensity of immunosuppression for patients on FK506 than those on cyclosporine.

Adolescent↗
PubMed1995

Biofeedback therapy for anorectal disorders in children.

The physiological rationale, methodology, and results of biofeedback therapy in the management of anorectal disorders in children are presented. Balloon manometry and surface electromyography (EMG) are current biofeedback methods used to teach improved recognition of rectal distension and coordination of muscle function to either maintain fecal continence or to allow proper defecation. These techniques have permitted a success rate of over 70% in the management of children with functional or organic anorectal disease refractory to conventional medical and behavioral therapy. Biofeedback therapy is recommended to assist in the successful rehabilitation of these patients.

Anus Diseases↗
PubMed1993

Revascularization technique for reduced-size liver transplantation for infants weighing less than 10 kg.

Reduced-size liver transplantation has been recognized as a powerful modality in alleviating the global donor shortage in pediatric liver transplantation. We describe, for the first time, a technique for revascularizing reduced-size grafts which has not been patterned after adult revascularization techniques. This revascularization method for reduced-size liver transplantation is particularly suitable for infants weighing < 10 kg. This technique differs from adult revascularization techniques in that the supraceliac aorta is always used as the origin for graft arterialization, and that the anastomoses are always performed in the following order: end-to-side donor celiac artery to supraceliac aorta anastomoses first, followed by the suprahepatic vena caval anastomoses, infrahepatic vena caval anastomoses, and then portal vein anastomoses. Hepatic artery thrombosis in infants weighing < 10 kg has occurred in 4 of 32 nonreduced versus 0 of 21 reduced transplantations (P = .05616, Z test, one tail). Adult revascularization was primarily used in the nonreduced group, whereas our proposed revascularization method was primarily used in the reduced group. We conclude that, for infants weighing < 10 kg receiving reduced grafts, this proposed technique should be used to decrease hepatic artery thrombosis.

Adult↗
PubMed1992

Graft involvement by Legionella in a liver transplant recipient.

Legionella pneumophila, serogroup 1, was identified by direct immunofluorescence in the lung and liver graft from a 2 1/2-month-old infant who underwent orthotopic liver transplantation because of fulminant hepatic failure secondary to neonatal hepatitis. The patient died of respiratory failure owing to this infection 22 days after transplantation despite treatment with erythromycin lactobionate. To our knowledge, this represents the first reported case of hepatic infection with Legionella in liver transplant recipients.

Fluorescent Antibody Technique↗
PubMed1990

The impairment of true glomerular filtration rate in long-term cyclosporine-treated pediatric allograft recipients.

We performed indium-111-DTPA plasma clearance studies in 61 pediatric kidney and liver recipients treated with cyclosporine to compare true glomerular filtration rate with calculated GFR (cGFR). The mean true GFR of 61.9 +/- 36.6 ml/min/1.73 m2 indicated renal impairment. The mean cGFR of 85.2 +/- 22.4 ml/min/1.73 m2 was significantly higher (P less than 0.001), and overestimated GFR by 38%. cGFR alone did not accurately reflect the degree of renal dysfunction. A group of 48 pediatric orthotopic liver transplant recipients was studied in more detail: 73% of these patients had a true GFR less than 70 ml/min/1.73 m2, while 85% had a true GFR below 90 ml/min/1.73 m2, the lower limit for normal GFR in children. The mean true GFR for patients treated more than 24 months with CsA was lower (P = 0.02) than patients treated with CsA for 12 to 24 months. OLT patients with normal true GFR (greater than 90 ml/min/1.73 m2) had significantly lower plasma CsA levels, and 50% of patients with a true GFR less than or equal to 50 ml/min/1.73 m2 had hypertension. There was no effect on true GFR of age, liver function, azathioprine use, or peritransplant treatment with other nephrotoxic drugs. We conclude that true GFR is significantly impaired in long-term CsA-treated allograft pediatric recipients. Calculations of GFR underestimate the degree of renal dysfunction. As patients treated greater than 24 months had the lowest true GFRs, the fall in GFR may be progressive.

Adolescent↗
PubMed1989

Home central venous hyperalimentation in fifteen patients with severe scleroderma bowel disease.

Fifteen patients with severe scleroderma bowel disease began receiving home central venous hyperalimentation (HCVH) between 1979 and 1987. The major reasons for instituting HCVH were intestinal pseudo-obstruction, malabsorption, and malnutrition. Eleven patients had an improved quality of life. Serious complications encountered over these 15,700 catheter-use days were 2 episodes of septicemia and 2 episodes of superior vena cava obstruction. Seven patients died, but none directly from their gastrointestinal disease or from the HCVH.

Adult↗