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Biomedical subjects

Frederick C Ryckman

Publications and source records attributed to Frederick C Ryckman.

At least 19 recordsLinked to original sources
PubMed2007

Isolated liver and multivisceral transplantation for total parenteral nutrition-related end-stage liver disease.

PURPOSE: Total parenteral nutrition (TPN) has prolonged survival in children with intestinal failure; however, end-stage liver disease owing to TPN-induced cholestasis (ESLD-TPN) may preclude its use. ESLD-TPN is an indication for isolated liver transplantation (ILT) or multivisceral transplantation (MVT). Isolated liver transplantation for ESLD-TPN should only be considered in patients who have the potential for enteral autonomy. METHODS: We retrospectively reviewed the records of patients with ESLD-TPN who underwent ILT (n = 7) or MVT (n = 5) between 1994 and 2005. The median age at the time of transplantation was 10.0 months. Intestinal failure followed necrotizing enterocolitis (n = 3), gastroschisis (n = 3), gastroschisis with volvulus (n = 3), gastroschisis with atresia (n = 1), malrotation (n = 1), and megacystis microcolon intestinal hypoperistalsis syndrome (n = 1). RESULTS: Isolated liver transplant patients had a median length of small bowel of 70 cm and tolerated a median of 50% of enteral calories. The median length of small bowel in patients who underwent MVT was 29 cm, and none tolerated more than 30% of goal enteral feeds. Reduced-size (n = 5) and whole-liver (n = 2) allografts were used for patients undergoing ILT. Patients undergoing MVT received liver-small bowel-pancreas (n = 4) or liver-small bowel-pancreas-colon (n = 1). Overall patient survival was 57% in ILT (median follow-up = 25.1 months); 3 survivors are TPN independent, and the fourth patient requires TPN 3 days/wk. Patient survival was 40% after MVT (median follow-up = 13.0 months); 1 MVT patient died of abuse 16.9 months after transplant and was TPN independent at the time of death. Both survivors are TPN independent. Bilirubin levels are within normal range in all survivors. CONCLUSION: Isolated liver transplantation for ESLD-TPN in the setting of intestinal failure is a viable option in patients who have the potential for enteral autonomy. Multivisceral transplantation is the only alternative in patients without the potential for intestinal recovery. Survival can be achieved in patients with ESLD-TPN, but mortality remains high for both procedures.

Child↗
PubMed2007

High prevalence of alpha-1-antitrypsin heterozygosity in children with chronic liver disease.

OBJECTIVE: Alpha-1-antitrypsin (A1AT) deficiency is the most common genetic cause of liver disease in children; however, the role of polymorphic heterogeneity in the A1AT gene as a modifier of other forms of pediatric liver disease is not clear. We hypothesized that non-M A1AT allele variants are more common in children with chronic liver disease than in the general population. METHODS: A retrospective, single-center study was performed in which A1AT phenotypes were obtained by reviewing charts of children with chronic liver disease. Chi-square analysis was used to compare allele frequencies in the population of children with liver disease with published epidemiologic data and to compare allele frequencies among disease subgroups. RESULTS: The frequency of A1AT Z and other alleles was increased in children with chronic liver disease (n = 241) when compared with the published reference database (P < 0.001). This increase remained significant when the population was divided into disease subsets: biliary atresia (n = 67) and other liver disease (n = 174) (P < 0.001 for both). Among children with biliary atresia referred for liver transplant evaluation, the presence of a non-M allele was associated with a lower mean age at transplant listing than the MM phenotype (235 vs 779 days, P = 0.036) and more frequent loss of native liver by 24 months of age (90% vs 65%, P = 0.04). CONCLUSIONS: A1AT non-M alleles are more frequent in children with chronic liver disease than in the general population. We speculate that these non-M alleles may act as genetic modifiers in pediatric liver disease in general and modulate disease progression in children with biliary atresia in particular.

Child↗
PubMed2006

Pediatric liver transplantation.

In the past two decades, pediatric liver transplantation has become the state-of-the-art operation with anticipated success and limited mortality. The future success of pediatric liver transplantation will require thoughtful solutions to the delicate balance of risk to donors and recipients, the complex needs of the acute postoperative patient, and the long-term challenges of chronic immunosuppression in these previously unsalvageable patients.

Child↗
PubMed2006

High prevalence of renal dysfunction in long-term survivors after pediatric liver transplantation.

OBJECTIVE: To determine the prevalence and identify variables associated with renal dysfunction in long-term survivors of pediatric liver transplantation. STUDY DESIGN: Data from 117 patients who survived>or=3 years after liver transplantation were analyzed. Demographic and clinical information was obtained from chart review and from a clinical care database. The dependent variable was renal function as determined by measured glomerular filtration rate (mGFR). Univariate and multivariate analyses were performed to identify independent variables associated with renal dysfunction (mGFR<70 mL/min per 1.73 m2). RESULTS: The average time since liver transplant was 7.6+/-3.4 years (range, 3 to 14.6 years). When the last available mGFR for all patients was analyzed, renal dysfunction was present in 32%. In the univariate analysis, mGFR at 1 year after transplant, cyclosporine immunosuppression, and time since transplant were significant; the second two were strongly collinear. Using multiple logistic regression modeling excluding time since transplant, cyclosporine and mGFR at 1 year after transplant were strongly associated with renal dysfunction. CONCLUSIONS: Renal dysfunction is a common complication in children who survive liver transplantation. Our observations are of critical importance because children may live long enough to move from a stage of renal insufficiency characterized by asymptomatic decreased GFR to symptomatic end-stage renal disease.

Adolescent↗
PubMed2006

The effect of a right-sided aortic arch on outcome in children with esophageal atresia and tracheoesophageal fistula.

UNLABELLED: During repair of an esophageal atresia with tracheoesophageal fistula (EA/TEF), a right-sided aortic arch (RAA) presents a technical challenge. We reviewed our experience with EA/TEF focusing on the impact of RAA. METHODS: A retrospective review of patients with EA/TEF at our institution from 1990 to 2004 was performed. Of 61 patients, 53 had a left aortic arch (LAA) and 8 had RAA. RESULTS: The mean gestational age and birth weight were similar between patients with LAA and RAA. There were more vascular rings in patients with RAA than with LAA (37.5% vs 3.8%, P = .009). A preoperative echocardiogram correctly identified the location of the arch in all with LAA but only 62.5% of those with RAA. Operative complications occurred in 25% of patients with RAA and 11% of patients with LAA. CONCLUSIONS: Management of a child with RAA and EA/TEF is technically challenging. Preoperative identification of the great vessel anomalies may impact operative decision making. Therefore, careful diagnostic evaluation of a patient with an aortic arch that cannot be easily defined by ECHO should be considered before definitive repair.

Aorta, Thoracic↗
PubMed2006

Nonoperative management of pectus carinatum.

BACKGROUND: Although surgery has been the mainstay of treatment of chondrogladiolar pectus carinatum (PC), several authors have advocated the benefits of nonoperative approaches to induce chest wall remodeling. Based on our initial success with compression bracing, we have integrated this modality into our treatment algorithm. METHOD: We reviewed the charts of all patients treated for PC at our pediatric hospital between 1997 and 2004. Patients were managed with observation, operative repair, and orthotic bracing that provides continuous anteroposterior sternal compression. The brace was worn for 14 to 16 hours per day until linear growth was complete or for a minimum of 2 years. RESULTS: One hundred patients were diagnosed with PC. Fifty-seven patients had no treatment and were monitored. Twenty-nine patients were fitted with a brace. Of these 29 patients, 3 were noncompliant, resulting in a compliance rate of 90%. Of the remaining brace patients, all have had positive outcomes with no observed complications. Seventeen patients underwent surgical repair. Their outcomes were also positive with no major complications. CONCLUSION: Our findings clearly demonstrate that compression bracing is a safe and effective treatment for children with chondrogladiolar PC. We currently offer this approach as a first-line treatment, reserving surgery for patients who are noncompliant and those who fail the nonoperative modality.

Adolescent↗
PubMed2006

Malignancy in pediatric transplant recipients.

Malignancy is a well defined complication of chronic immunosuppression. Post transplant malignancies appear to be related to cumulative doses of immunosuppression, and in pediatric patients, acute infection of previously naive patients. The most commonly encountered malignancy in this age population is Post Transplant Lymphoproliferative Disorder (PTLD). PTLD is not a single entity but rather represents a continuum of disease. Treatment of PTLD should be initiated with immunosuppression reduction. Standard dose chemotherapy leads to significant morbidity. With the introduction of anti-CD20 antibody treatment with rituximab, chemotherapy has become second line therapy. The occurrence of solid malignancy appears to be associated with chronic immunosuppression. These cancers include those of skin, gynecologic organs, and the rectum, all of which appear to have the strongest association with viral mediators. Several strategies have been postulated to minimize the occurrence of malignancy. These include ganciclovir prophylaxis for the prevention of PTLD and the use of mychophenolic acid and TOR inhibitor maintenance to diminish the incidence of PTLD and solid malignancies. This leaves transplant physicians with several new and novel immunosuppressive agents with uncertain oncologic potentials that will need to be examined over the next decade.

Adolescent↗
PubMed2006

Pediatric liver transplantation.

Liver transplantation has become the accepted standard of care in the treatment of a child with a failing liver. Advances in the management of critical care and immunosuppression along with the development of innovative operative procedures have improved outcome such that 5-year survival rates of 80% to 90% are expected following liver transplantation. Organ allocation schemes have evolved in an effort to better stratify recipient risk thereby more appropriately distributing deceased donor grafts. A persistent shortage of appropriate donors continues to contribute to patient mortality. The consequences of long-term immunosuppression have become increasingly apparent such that health care providers need to be aware of the side effects of chronic immunosuppression. New strategies need to be defined to minimize the need of continuous immunosuppression. The continued success of pediatric liver transplantation will require multi-disciplinary health care teams comprised of general pediatricians, pediatric hepatologists, transplant surgeons, and transplant coordinators who focus on the complex needs of the transplant recipient.

Adolescent↗
PubMed2005

Low-dose chemotherapy for Epstein-Barr virus-positive post-transplantation lymphoproliferative disease in children after solid organ transplantation.

PURPOSE: To evaluate the efficacy of a low-dose chemotherapy regimen in children with Epstein-Barr virus (EBV) -positive, post-transplantation lymphoproliferative disease (PTLD) after organ transplantation who have experienced failure with front-line therapy for PTLD. PATIENTS AND METHODS: Eligible patients received cyclophosphamide (600 mg/m2 intravenous for 1 day) and prednisone (2 mg/kg orally for 5 days) every 3 weeks for six cycles. RESULTS: Thirty-six patients treated on study were assessable for analyses. Front-line therapies for PTLD before study entry included immune suppression reduction or withdrawal (n = 36), antiviral therapy (n = 33), surgical resection (n = 8), rituximab (n = 2), and interferon alfa (n = 1). Reasons for failure of front-line therapy included progressive disease (PD; n = 33) and persistent disease with concurrent allograft rejection (n = 3). Thirty patients (83%) had stage III to IV disease, 92% had extranodal disease, and 75% had > or = three sites of disease. The overall response rate was 83% (75% complete response + 8% partial response). The relapse rate was 19%, with only one of five relapsed patients alive and disease-free. Four patients presented with fulminant, disseminated PTLD; only one of these four patients achieved a response, and all four died of PD. Two patients died of treatment-related toxicity. Three patients (8%) experienced allograft loss, but two of the three patients are alive and disease-free after a second transplantation. The 2-year overall, relapse-free, and failure-free (without PTLD and with functioning original allograft) survival rates were 73%, 69%, and 67%, respectively. CONCLUSION: This low-dose chemotherapy regimen is effective for children with EBV-positive, nonfulminant PTLD who have experienced treatment failure with front-line therapy, and this study represents the largest series of PTLD patients treated prospectively with a uniform chemotherapy regimen.

Adolescent↗
PubMed2005

A novel approach to managing variation: outpatient therapeutic monitoring of calcineurin inhibitor blood levels in liver transplant recipients.

OBJECTIVE: To apply the principles of statistical process control (SPC) to manage calcineurin inhibitor (CNI) blood levels. We hypothesized that the use of SPC would increase the proportion of CNI blood levels in the target range. STUDY DESIGN: The study population consisted of 217 patients more than 3 months after liver transplantation. After demonstration of proof of concept using the rapid cycle improvement process, SPC was applied to the entire population. The change package included definition of target ranges for CNI, implementation of a web-based tool that displayed CNI blood levels on a control chart, and implementation of a protocol and a checklist for management of CNI blood levels. The principal outcome measure was the proportion of CNI blood levels in the target range. RESULTS: In the pilot study, the proportion of CNI blood levels in the target range increased from 50% to 85%. When the protocol was spread to the entire population, the proportion of drug levels in the target range increased to 77% from 50% (P < .001), whereas the range of CNI levels decreased. The rate of allograft rejection did not change. CONCLUSIONS: Utilization of SPC increased the proportion of CNI blood levels in target range. These observations may be applicable to the care of other chronic healthcare problems.

Ambulatory Care↗
PubMed2004

Tailgut cyst in a child.

Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital lesion found in the presacral space. The lesion has been infrequently reported in the literature. We report the MRI findings of a tailgut cyst in a 2-year-old girl who presented with a sacral dimple and skin discoloration.

Child, Preschool↗
PubMed2004

Outcome after pediatric liver transplantation impact of living donor transplantation on cost.

OBJECTIVE: To compare the direct health care cost of living donor liver transplantation (LDLT) with that of cadaver donor liver transplantation (CDLT) in children and identify predictors of cost. STUDY DESIGN: All 16 children who underwent LDLT from January 1997 through January 2002 at Cincinnati Children's Hospital Medical Center comprised the study population. They were matched for age, diagnosis, and nutritional status with 31 children who received CDLT during the same era. A historic cohort analysis was performed. RESULTS: There was no difference in the 1-year mortality rates between both groups. Costs associated with graft retrieval contributed 15.3% and 31% of the initial transplant cost for LDLT and CDLT, respectively. Mean cost of care in the first year was 60.3% higher for LDLT than CDLT (P=.01). Multivariate analysis identified biliary complications and insurance status as predictors of cost for initial transplantation (R(2)=0.57), whereas biliary complications and pediatric end stage liver disease scores were identified as predictors of cost of care in the first year after transplantation (R(2)=0.77). CONCLUSIONS: The comprehensive cost of LDLT in the first year after transplantation is higher than cadaveric transplantation. This must be balanced against the time spent and care needs of patients on the waiting list.

Cadaver↗
PubMed2004

Impact of liver transplantation on HRQOL in children less than 5 years old.

Our primary goal was to assess health related quality of life (HRQOL) at transplantation and 1 yr after transplantation in pediatric liver transplant patients aged less than 5 years. We conducted a prospective longitudinal study of HRQOL in pediatric liver transplant recipients, aged less than 5 years to define the impact of liver transplantation on HRQOL and identify factors that predict HRQOL after transplantation. The infant toddler health status questionnaire (ITHQ) was completed at the time of listing for liver transplantation and at 6 and 12 months after liver transplantation. The primary outcome measures were the subscale scores that comprise ITHQ. The mean age (+/-s.e.m.) of the enrolled patients (n = 45) at transplantation was 1.4 (+/-1.2) yr. Thirty-eight (84%) of the enrolled patients completed the study. The highest mean baseline scores of 78.6 (+/-3.3) were for global mental health (GlobalMH). ITHQ subscale scores increased steadily after transplantation. The greatest increase was in the first 6 months after transplant. At 1 yr after transplantation, there were significant increases in all of the ITHQ subscale scores except for GlobalMH. ITHQ subscales were similar for patients who received LDLT compared with those who received cadaver donor liver transplantation (CDLT) at baseline and a year after transplant. Time elapsed as transplantation was a significant predictor of functional health in all of the models generated. Scores for general health (GH), global health (GGH), parental time-impact (PT) and parental time-emotion (PE) were higher for male children. Family cohesion (FC) improved with time elapsed since transplant and increased number of inpatient days. HRQOL improves after transplantation in all of our patients irrespective of the donor type. Functional health scores were higher in patients with normal serum bilirubin at 1 yr post-transplant. Assessment of HRQOL should be an integral part of care for liver transplant patients and their caregivers.

Bilirubin↗
PubMed2003

Determination of risk factors for Epstein-Barr virus-associated posttransplant lymphoproliferative disorder in pediatric liver transplant recipients using objective case ascertainment.

BACKGROUND: Previous studies have suggested an increased risk of Epstein-Barr virus-associated posttransplant lymphoproliferative disorder (EBV-PTLD) in patients receiving tacrolimus for immunosuppression. We hypothesized that after correction for confounding variables, immunosuppression with tacrolimus is not associated with an increased risk of EBV-PTLD. METHODS: Potential cases of EBV-PTLD, identified by chart review, were independently ascertained by three clinicians and defined using published criteria. Agreement in diagnosing EBV-PTLD was measured using Kappa coefficients. Unadjusted and adjusted relative risk estimates were determined using proportional hazards regression. RESULTS: Twenty-three cases of EBV-PTLD were identified in 221 patients, a proportion of 10.4% (95% confidence interval [CI]: 6.4%-14.4%). Multivariable analysis revealed that immunosuppression with tacrolimus was associated with an increased risk of EBV-PTLD (relative risk 3.10: 95% CI: 1.21-7.92), as was age at transplantation as a continuous variable (parameter estimate -0.15, P=0.03). Kappa coefficients in diagnosing EBV-PTLD and subclassifying as neoplastic and non-neoplastic EBV-PTLD were 0.73 (95% CI: 0.54-0.93) and 0.54 (95% CI: 0.40-0.68), respectively. Patients with neoplastic PTLD demonstrated a lower probability of survival than patients with non-neoplastic PTLD and non-cases. CONCLUSIONS: Immunosuppression with tacrolimus and young age at transplantation are associated with an increased risk of EBV-PTLD in children undergoing liver transplantation, although we cannot exclude detection bias as an explanation for this observed increase. Good agreement between observers can be achieved using previously published criteria for defining EBV-PTLD. Patients with neoplastic EBV-PTLD may have a worse prognosis, and thus identification of risk factors for the development of this subtype of the disorder may be more important.

Aging↗
PubMed2003

Risk of hearing impairment in pediatric liver transplant recipients: a single center study.

As survival rates following liver transplantation have increased, health care providers must assess the impact of transplantation on dimensions other than traditional medical measures. Hearing impairment may adversely impact social, emotional, cognitive, academic, and speech and language development. We hypothesized that children who undergo liver transplantation are at risk for hearing impairment due to exposure to ototoxic drugs. We conducted a review of 74 children who had undergone liver transplantation between December 1996 and September 2000 at Cincinnati Children's Hospital Medical Center. Hearing was assessed at discharge by an audiologist using age and developmentally appropriate techniques. The principal outcome measure was sensorineural hearing impairment. Independent variables were age at transplantation, United Network for Organ Sharing (UNOS) status at transplantation, primary diagnosis, post-transplant length of hospital stay, days of treatment with aminoglycosides, and days of treatment with loop diuretics. Eleven of 74 children (15%) had sensorineural hearing loss, of whom four had severe to profound hearing loss. Multivariate analyses showed that the adjusted relative risk for hearing loss in patients with hepatoblastoma was 66 and that there was a 5% increase risk for hearing loss for each additional day of hospitalization. Age at transplantation, UNOS status, and days of treatment with loop diuretics or aminoglycosides did not achieve significance in the model. Sensorineural hearing impairment occurs in a subset of pediatric patients following liver transplantation. Patients with hepatoblastoma or those who experience prolonged hospitalization after transplantation are at increased risk. Our observations are of particular importance for pediatric liver transplant recipients since the median age at transplantation is 12-18 months, a critical period for language acquisition.

Biliary Atresia↗
PubMed2003

Health-related quality of life in pediatric liver transplant recipients: A single-center study.

The goals of the present study were (1) to measure health-related quality of life (HRQOL) in pediatric liver transplantation (LT), (2) to identify demographic and clinical factors that correlate with HRQOL, and (3) to compare two instruments that have been used to measure HRQOL in children and adolescents. We conducted a single-center cross-sectional study of 77 pediatric LT recipients ages 5 to 18 years, all of whom had had LT at least 6 months previously. We used the Child Health Questionnaire Parent Form 50 (CHQPF50) and the PedsQL4.0 to determine measured dimensions of physical and psychosocial health from the parents' perspective. Individual scale scores range from 0 to 100, with higher scores reflecting better health. Data on demographics, clinical status at transplantation, posttransplantation clinical course, and graft function were collected to identify predictors of posttransplantation HRQOL. Fifty-three percent of the liver transplant recipients had biliary atresia, 78% were white, and 61% were female. The mean age at LT was 3.8 +/- 3.6 years, and the range of time since LT was 1 to 15 years. HRQOL in pediatric liver transplant recipients was lower than that reported for healthy children but similar to that for children with other chronic illness. Age at transplantation, the time elapsed since transplantation, hospitalizations within the previous year, maternal education, and race were significant predictors of physical health. Age at transplantation and maternal education predicted psychosocial function. HRQOL was decreased in a population of pediatric liver transplant recipients compared with the general population and similar to that for children with chronic illness. Prospective longitudinal studies will permit us to define predictors of HRQOL at different periods of time after transplantation. The information gained from this study will help us to better define expectations and the clinical course after liver transplantation to patients and their families.

Adolescent↗
PubMed2003

Bone mineral density in long-term survivors following pediatric liver transplantation.

We sought to estimate the prevalence of reduced bone mass, defined by lumbar spine bone mineral density (LS-BMD) (z-score < -2.0), and to determine the factors associated with LS-BMD after liver transplantation in children and adolescents. LS-BMD z-scores were measured in a sample of subjects who had undergone liver transplantation in childhood or adolescence using dual energy x-ray absorptiometry (DXA). One hundred nine patients underwent DXA. The mean age at transplantation was 4.3 years (median, 1.8 years), and mean duration since transplantation was 6.2 years (median, 5.8 years). The mean weight z-score was -0.130 (SD, 1.26). The mean LS-BMD z-score was -0.243 (SD, 1.27). Eight patients, or 7.3% (95% confidence interval [CI], 2.4% to 12.2%), had reduced bone mass. Compared with those without reduced bone mass, subjects with reduced bone mass were more likely to have been treated for rejection at least once (87.5% versus 51.5%; P =.07), and had greater cumulative exposure to prednisone during the year before DXA (92.3 versus 26.2 mg/kg/y; P =.001). Multiple linear regression determined that LS-BMD z-score was positively associated with time since transplantation and weight z-score and negatively associated with cumulative prednisone exposure. Serum 25-OH vitamin D was measured and reduced (< 15 ng/mL) in 5 of 87 patients, one of whom had reduced bone mass. In conclusion, the prevalence of reduced bone mass was 7.3% in our population. Only certain patients appear to be at risk for low BMD, including those with a history of rejection. Screening for reduced bone mass may be appropriate for these patients.

Absorptiometry, Photon↗