Risk of lymphoma subtypes after solid organ transplantation in the United States.

BACKGROUND: Solid organ transplant recipients have high risk of lymphomas, including non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). A gap in our understanding of post-transplant lymphomas involves the spectrum and associated risks of their many histologic subtypes. METHODS: We linked nationwide data on solid organ transplants from the US Scientific Registry of Transplant Recipients (1987-2008) to 14 state and regional cancer registries, yielding 791 281 person-years of follow-up for 19 distinct NHL subtypes and HL. We calculated standardised incidence ratios (SIRs) and used Poisson regression to compare SIRs by recipient age, transplanted organ, and time since transplantation. RESULTS: The risk varied widely across subtypes, with strong elevations (SIRs 10-100) for hepatosplenic T-cell lymphoma, Burkitt's lymphoma, NK/T-cell lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma (both systemic and primary cutaneous forms). Moderate elevations (SIRs 2-4) were observed for HL and lymphoplasmacytic, peripheral T-cell, and marginal zone lymphomas, but SIRs for indolent lymphoma subtypes were not elevated. Generally, SIRs were highest for younger recipients (<20 years) and those receiving organs other than kidneys. CONCLUSION: Transplant recipients experience markedly elevated risk of a distinct spectrum of lymphoma subtypes. These findings support the aetiologic relevance of immunosuppression for certain subtypes and underscore the importance of detailed haematopathologic workup for transplant recipients with suspected lymphoma.

Racial/ethnic differences in cancer risk after kidney transplantation.

Transplant recipients have elevated cancer risk, but it is unknown if cancer risk differs across race and ethnicity as in the general population. US kidney recipients (N = 87,895) in the Transplant Cancer Match Study between 1992 and 2008 were evaluated for racial/ethnic differences in risk for six common cancers after transplantation. Compared to white recipients, black recipients had lower incidence of non-Hodgkin lymphoma (NHL) (adjusted incidence rate ratio [aIRR] 0.60, p<0.001) and higher incidence of kidney (aIRR 2.09, p<0.001) and prostate cancer (aIRR 2.14, p<0.001); Hispanic recipients had lower incidence of NHL (aIRR 0.64, p = 0.001), lung (aIRR 0.41, p < 0.001), breast (aIRR 0.53, p = 0.003) and prostate cancer (aIRR 0.72, p = 0.05). Colorectal cancer incidence was similar across groups. Standardized incidence ratios (SIRs) measured the effect of transplantation on cancer risk and were similar for most cancers (p≥0.1). However, black and Hispanic recipients had larger increases in kidney cancer risk with transplantation (SIRs: 8.96 in blacks, 5.95 in Hispanics vs. 4.44 in whites), and only blacks had elevated prostate cancer risk following transplantation (SIR: 1.21). Racial/ethnic differences in cancer risk after transplantation mirror general population patterns, except for kidney and prostate cancers where differences reflect the effects of end-stage renal disease or transplantation.

The aggressive phenotype revisited: utilization of higher-risk liver allografts.

Organ shortage has led to increased utilization of higher risk liver allografts. In kidneys, aggressive center-level use of one type of higher risk graft clustered with aggressive use of other types. In this study, we explored center-level behavior in liver utilization. We aggregated national liver transplant recipient data between 2005 and 2009 to the center-level, assigning each center an aggressiveness score based on relative utilization of higher risk livers. Aggressive centers had significantly more patients reaching high MELDs (RR 2.19, 2.33 and 2.28 for number of patients reaching MELD>20, MELD>25 and MELD>30, p<0.001), a higher organ shortage ratio (RR 1.51, 1.60 and 1.51 for number of patients reaching MELD>20, MELD>25 and MELD>30 divided by number of organs recovered at the OPO, p<0.04), and were clustered within various geographic regions, particularly regions 2, 3 and 9. Median MELD at transplant was similar between aggressive and nonaggressive centers, but average annual transplant volume was significantly higher at aggressive centers (RR 2.27, 95% CI 1.47-3.51, p<0.001). In cluster analysis, there were no obvious phenotypic patterns among centers with intermediate levels of aggressiveness. In conclusion, highwaitlist disease severity, geographic differences in organ availability, and transplant volume are the main factors associated with the aggressive utilization of higher risk livers.

Early hospital readmission after kidney transplantation: patient and center-level associations.

Early hospital readmission (EHR) is associated with increased morbidity, costs and transition-of-care errors. We sought to quantify rates of and risk factors for EHR after kidney transplantation (KT). We studied 32 961 Medicare primary KT recipients (2000-2005) linked to Medicare claims through the United States Renal Data System. EHR was defined as at least one hospitalization within 30 days of initial discharge after KT. The association between EHR and recipient and transplant factors was explored using Poisson regression; hierarchical modeling was used to account for study center-level differences. The overall EHR rate was 31%, and 19 independent patient-level factors associated with EHR were identified: recipient factors included older age, African American race and various comorbidities; transplant factors included ECD, length of stay and lack of induction therapy. The unadjusted rate of EHR by center ranged from 18% to 47%, but conventional center-level factors (percent African American, percent age > 60, percent deceased donor and percent expanded criteria donor) were not associated with EHR. However, intermediate total volume and average length of stay were associated with increased EHR risk. Better identification of patients at risk for early hospital readmission following KT may guide discharge planning and early posttransplant outpatient monitoring.

The aggressive phenotype: center-level patterns in the utilization of suboptimal kidneys.

Despite the fact that suboptimal kidneys have worse outcomes, differences in waiting times and wait-list mortality have led to variations in the use of these kidneys. It is unknown whether aggressive center-level use of one type of suboptimal graft clusters with aggressive use of other types of suboptimal grafts, and what center characteristics are associated with an overall aggressive phenotype. United Network for Organ Sharing (UNOS) data from 2005 to 2009 for adult kidney transplant recipients was aggregated to the center level. An aggressiveness score was assigned to each center based on usage of suboptimal grafts. Deceased-donor transplant volume correlated with aggressiveness in lower volume, but not higher volume centers. Aggressive centers were mostly found in regions 2 and 9. Aggressiveness was associated with wait-list size (RR 1.69, 95% CI 1.20-2.34, p = 0.002), organ shortage (RR 2.30, 95% CI 1.57-3.37, p < 0.001) and waiting times (RR 1.75, 95% CI 1.20-2.57, p = 0.004). No centers in single-center OPOs were classified as aggressive. In cluster analysis, the most aggressive centers were aggressive in all metrics and vice versa; however, centers with intermediate aggressiveness had phenotypic patterns in their usage of suboptimal kidneys. In conclusion, wait-list size, waiting times, geographic region and OPO competition seem to be driving factors in center-level aggressiveness.

Pre-transplant myeloid dendritic cell deficiency associated with cytomegalovirus infection and death after kidney transplantation.

BACKGROUND: Dendritic cells (DCs) are potent antigen-presenting cells critical for immunity. We previously demonstrated a significant association between pre-transplant blood myeloid dendritic cell (mDC) and plasmacytoid dendritic cell (pDC) deficiency and post-transplant BK viremia in renal transplant recipients. In the current post-hoc analysis, we studied the association of these same pre-transplant DC levels with other post-transplant outcomes. METHODS: Pre-transplant peripheral blood mDC and pDC levels were quantified using flow cytometry in 78 patients undergoing kidney transplantation. Post-transplant outcomes were analyzed, including infection, rejection, and patient death, with a median follow-up of 5.3 years. Associations between DC levels and outcomes were assessed using logistic regression analysis and Cox proportional hazards models. RESULTS: An independent association of mDC levels with post-transplant cytomegalovirus infection (adjusted odds ratio 7.0, P = 0.01) and patient death (adjusted hazard ratio 13.0, P = 0.015) was found. No associations were demonstrated between levels of either DC subtype and bacterial infections or rejection. CONCLUSIONS: Pre-transplant mDC deficiency is significantly associated with CMV infection and death after kidney transplantation.

Estimating the potential pool of HIV-infected deceased organ donors in the United States.

Human immunodeficiency virus (HIV) is no longer a contraindication to transplantation. For HIV-infected patients, HIV-infected deceased donors (HIVDD) could attenuate the organ shortage and waitlist mortality. However, this practice would violate United States federal law. The goal of this study was to estimate the potential impact of legalizing transplantation of HIV-infected organs by quantifying the potential pool of HIVDD. Using Nationwide Inpatient Sample (NIS) data, HIV-infected deaths compatible with donation were enumerated. Using HIV Research Network (HIVRN) data, CD4 count, plasma HIV-1 RNA level, AIDS-defining illnesses and causes of death were examined in potential HIVDD. Using UNOS data, evaluated donors who later demonstrated unanticipated HIV infections were studied. From NIS, a yearly average of 534 (range: 481-652) potential HIVDD were identified, with 63 (range: 39-90) kidney-only, 221 (range: 182-255) liver-only and 250 (range: 182-342) multiorgan donors. From HIVRN, a yearly average of 494 (range: 441-533) potential HIVDD were identified. Additionally, a yearly average of 20 (range: 11-34) donors with unanticipated HIV infection were identified from UNOS. Deceased HIV-infected patients represent a potential of approximately 500-600 donors per year for HIV-infected transplant candidates. In the current era of HIV management, a legal ban on the use of these organs seems unwarranted and likely harmful.

MELD Exceptions and Rates of Waiting List Outcomes.

Model for End-stage Liver Disease (MELD)-based allocation of deceased donor livers allows exceptions for patients whose score may not reflect their true mortality risk. We hypothesized that organ procurement organizations (OPOs) may differ in exception practices, use of exceptions may be increasing over time, and exception patients may be advantaged relative to other patients. We analyzed longitudinal MELD score, exception and outcome in 88 981 adult liver candidates as reported to the United Network for Organ Sharing from 2002 to 2010. Proportion of patients receiving an HCC exception was 0-21.4% at the OPO-level and 11.9-18.8% at the region level; proportion receiving an exception for other conditions was 0.0%-13.1% (OPO-level) and 3.7-9.5 (region-level). Hepatocellular carcinoma (HCC) exceptions rose over time (10.5% in 2002 vs. 15.5% in 2008, HR = 1.09 per year, p<0.001) as did other exceptions (7.0% in 2002 vs. 13.5% in 2008, HR = 1.11, p<0.001). In the most recent era of HCC point assignment (since April 2005), both HCC and other exceptions were associated with decreased risk of waitlist mortality compared to nonexception patients with equivalent listing priority (multinomial logistic regression odds ratio [OR] = 0.47 for HCC, OR = 0.43 for other, p<0.001) and increased odds of transplant (OR = 1.65 for HCC, OR = 1.33 for other, p<0.001). Policy advantages patients with MELD exceptions; differing rates of exceptions by OPO may create, or reflect, geographic inequity.

Orosomucoid content of pleural and peritoneal effusions.

22 nonneoplastic, noninflammatory effusions (cirrhosis and congestive heart failure), 12 non-neoplastic inflammatory effusions (tuberculosis, lupus erythematosus, rheumatoid arthritis, and idiopathic pleuropericarditis), and 58 neoplastic effusions (cancer of lung, breast, ovary, and pancreas, and lymphoma) were analyzed by radial immunodiffusion for orosomucoid concentration. The average concentration +/-SE was 35+/-4, 65+/-17, and 130+/-13 mg/100 ml in the three types of effusion, respectively. By gel filtration and ion exchange chromatography, orosomucoid was isolated from 12 nonmalignant and 14 malignant fluids. The orosomucoid preparations reacted as single components in acrylamide gel electrophoresis at pH 9.0, and in immunodiffusion and immunoelectrophoresis against antisera to human serum and to human plasma orosomucoid. In radial immunodiffusion, the slope of the line relating concentration to the square of the diameter of the precipitate area was identical for orosomucoid isolated from normal human plasma and from nonneoplastic effusions, but was subnormal for orosomucoid isolated from neoplastic fluids. All orosomucoid preparations had normal amino acid composition. Orosomucoid from the nonmalignant effusions had normal carbohydrate content. 11 of 14 samples of orosomucoid isolated from neoplastic fluids had abnormalities in carbohydrate composition, consisting of subnormal content of sialic acid (11 of 14), hexose (10 of 14), and hexosamine (3 of 14), and abnormally high content of hexosamine (4 of 14). Discriminant analysis showed that concentration of orosomucoid distinguished between neoplastic and nonneoplastic noninflammatory effusions more effectively than concentration of total protein, albumin, alpha(1), alpha(2), beta, or gamma-globulin.

Anabolic actions of reduced and S-carbamidomethylated human growth hormone and its plasmin digest in man.

Six children aged 12-15 yr, deficient in endogenous growth hormone, were each treated, after a 7-day control period, for 7 days with 0.0168, 0.052, and 0.168 U/kg body wt3/4 human growth (hGH) (doses A, B, and C, respectively) in separate metabolic balance studies. Doses B and C caused a dose-related retention of N, P, K, Na, and Cl in ratios of 1/0.069/4.5/7.5/5.6. These ratios indicate increments in masses of protoplasm/extracellular fluid (ECF)/bone in ratios of 1/2.0/ less than 0.001. Three of the children were also treated with doses A, B, and C of reduced and carbamidomethylated hGH (RCAM-hGH). Doses B and C caused 1.2-2.8 times as much retention of N, P, and K, and 0.3-0.5 times as much retention of Na and Cl, as did the corresponding doses of hGH. The plasmin digest of RCAM-hGH gave results generally similar to RCAM-hGH. For RCAM-hGH and its plasmin digest, N, P, K, Na, and Cl were retained in ratios of about 1/0.14/5.4/2.2/2.1, indicating increments of protoplasm/ECF/bone of about 1/0.8/0.05. These findings indicate that reduction and carbamidomethylation alter the anabolic actions of hGH in man in both quantitative and qualitative manner. RCAM-hGH is more potent in stimulating enlargement of protoplasm and bone, and less potent in stimulating expansion of ECF, than is the native hormone. The profile of anabolic actions of RCAM-hGH in man does not appear to be further altered by digestion with plasmin.

Improved formulas for the estimation of renal depth in adults.

Commercial techniques are available to calculate effective renal plasma flow (ERPF) or glomerular filtration rate (GFR) based on the percent injected dose in the kidney 1-2 or 2-3 min post-injection; renal depth is estimated by the Tonnesen equations. Since the Tonnesen equations were derived from ultrasound measurements obtained at an oblique angle in sitting patients, we compared the renal depths obtained from the Tonnesen equations with the renal depth measured by computed tomography in supine patients, the most common position for radionuclide renography. The renal depth, height, weight, age and sex were determined for 126 patients undergoing CT scanning. Patients with obvious renal or abdominal pathology were excluded. The Tonnesen equations significantly underestimated renal depth. Using stepwise linear regression analysis, we derived a set of equations based on age, height and weight and applied these prospectively to a new set of 75 patients. In addition, a second set of equations were derived for the new data. There was no difference in the results for the two equations. We then pooled both studies and derived a combined set of equations: right renal depth (mm) = 153.1 weight/height + 0.22 age + 0.77 and left renal depth (mm) = 161.7 weight/height + 0.27 age - 9.4, where weight is in kilograms and height is in centimeters. The correlation coefficients were 0.81 and 0.83 for the right and left kidneys respectively with standard errors of the estimate of 10.2 and 10.1 mm. These equations provide a much better estimate of renal depth in the supine patient than the Tonnesen equations.

Measurement of the Cobb angle on radiographs of patients who have scoliosis. Evaluation of intrinsic error.

To quantitate the intrinsic error in measurement, fifty anteroposterior radiographs of patients who had scoliosis were each measured on six separate occasions by four orthopaedic surgeons using the Cobb method. For the first two measurements (Set I), each observer selected the end-vertebrae of the curve; for the next two measurements (Set II), the end-vertebrae were pre-selected and constant. The last two measurements (Set III) were obtained in the same manner as Set II, except that each examiner used the same protractor rather than the one that he carried with him. The pooled results of all four observers suggested that the 95 per cent confidence limit for intraobserver variability was 4.9 degrees for Set I, 3.8 degrees for Set II, and 2.8 degrees for Set III. The interobserver variability was 7.2 degrees for Set I and 6.3 degrees for Sets II and III. The mean angles differed significantly between observers, but the difference was smaller when the observers used the same protractor.

Fixational ocular motor control is plastic despite visual deprivation.

The aim of this study was to assess the plasticity of human voluntary fixational eye movement control in relation to visual experience/chronic visual deprivation. Twelve blind adults participated (self-reported vision < or = light perception in each eye; age range = 23-56 years; visual experience range = 0-28 years; blindness duration range = 6-55 years). Infrared-based recordings of horizontal eye movements were made before, during, and immediately after three 30-s periods of auditory ocular motor feedback, while participants were instructed to look straight ahead and keep their eyes as steady as possible. Percent change in horizontal displacement of the eye during and after feedback was compared with the no-feedback baseline. Eleven of the 12 individuals demonstrated feedback-mediated increase in eye stability, which improved as a function of visual experience. Improved eye stability was inversely related to duration of blindness. Clearly, blind adults can use nonvisual external feedback to stabilize gaze. Thus, the fixational subsystem can exhibit improved voluntary control despite chronic visual deprivation. Possible cortical and subcortical mechanisms are discussed.

Antimicrobial susceptibility in gram-negative bacteremia: are nosocomial isolates really more resistant?

Bloodstream isolates of gram-negative aerobic bacilli from nosocomial infections are more likely to be resistant to antimicrobial agents than isolates from community-acquired cases are. It is not clear, however, how much this is due to the markedly different distribution of organisms in the two groups. We compared the susceptibilities of organisms of a given species which caused community-acquired bacteremia with the susceptibilities of isolates from nosocomial cases. Nine antimicrobial agents were tested against 1,077 isolates which were obtained during a 4-year nonepidemic period. Marked differences in crude rates of resistance were noted for all isolates from nosocomial cases versus all isolates from cases acquired in the community. When results were adjusted for the different organism distributions in the two groups, statistically significant differences were found for only six drug-organism pairs; in each of these, resistance rates were higher in nosocomial isolates. However, when results were further adjusted for the effect of multiple analyses, no significant differences were seen. The major factor leading to the greater prevalence of antimicrobial resistance in our hospital organisms was the markedly different distribution of organisms in the nosocomial and community-acquired groups. For individual organisms, greater resistance in nosocomial strains was confined to certain drugs. Factors that influence differences in organism distribution may not be solely the result of antimicrobial use.