Implementation of genomic medicine for rare disease in a tertiary healthcare system: Mayo Clinic Program for Rare and Undiagnosed Diseases (PRaUD).

BACKGROUND: In the United States, rare disease (RD) is defined as a condition that affects fewer than 200,000 individuals. Collectively, RD affects an estimated 30 million Americans. A significant portion of RD has an underlying genetic cause; however, this may go undiagnosed. To better serve these patients, the Mayo Clinic Program for Rare and Undiagnosed Diseases (PRaUD) was created under the auspices of the Center for Individualized Medicine (CIM) aiming to integrate genomics into subspecialty practice including targeted genetic testing, research, and education. METHODS: Patients were identified by subspecialty healthcare providers from 11 clinical divisions/departments. Targeted multi-gene panels or custom exome/genome-based panels were utilized. To support the goals of PRaUD, a new clinical service model, the Genetic Testing and Counseling (GTAC) unit, was established to improve access and increase efficiency for genetic test facilitation. The GTAC unit includes genetic counselors, genetic counseling assistants, genetic nurses, and a medical geneticist. Patients receive abbreviated point-of-care genetic counseling and testing through a partnership with subspecialty providers. RESULTS: Implementation of PRaUD began in 2018 and GTAC unit launched in 2020 to support program expansion. Currently, 29 RD clinical indications are included in 11 specialty divisions/departments with over 142 referring providers. To date, 1152 patients have been evaluated with an overall solved or likely solved rate of 17.5% and as high as 66.7% depending on the phenotype. Noteworthy, 42.7% of the solved or likely solved patients underwent changes in medical management and outcome based on genetic test results. CONCLUSION: Implementation of PRaUD and GTAC have enabled subspecialty practices advance expertise in RD where genetic counselors have not historically been embedded in practice. Democratizing access to genetic testing and counseling can broaden the reach of patients with RD and increase the diagnostic yield of such indications leading to better medical management as well as expanding research opportunities.

Characteristics and Graft Outcomes of Kidney Transplant Candidates with Enteric Risk Factors and Elevated Plasma Oxalate Levels.

INTRODUCTION: This study describes patient characteristics and examines graft function of kidney transplant recipients (without primary hyperoxaluria) with elevated plasma oxalate (POx) and enteric risk factors prior to transplant at our institution. METHODS: Kidney transplant recipients between 2012 and 2020 with elevated POx at the time of kidney transplant evaluation were included. A matched control cohort was gathered using patient/donor age, living/deceased donor type, panel reactive antibody, kidney donor profile index, and human leukocyte antigen mismatch as matching variables. Graft function at 1 year and at last follow-up was reported. RESULTS: A total of 106 patients with elevated POx were identified. A third of the patients had Roux-en-Y gastric bypass, a third had other enteric risks, and a third did not have an identifiable enteric risk. Median eGFR (estimated glomerular filtration rate) at 1 year and at last follow-up was similar between cases and controls except for subgroup of patients with pre-transplant POx >30 µmol/L where 1-year eGFR was lower compared to controls. Across eGFR categories, more cases were in eGFR category <30 mL/min/1.73 m2 compared to controls. CONCLUSION: Roux-en-Y gastric bypass is the most common identifiable risk for elevated POx in kidney transplant candidates. 1-year graft function was not inferior in cases compared to matched controls except for subgroup with POx >30 µmol/L pre-transplant.

GFR estimated with creatinine rather than cystatin C is more reflective of the true risk of adverse outcomes with low GFR in kidney transplant recipients.

BACKGROUND: Serum cystatin C-based estimated glomerular filtration rate (eGFRcys) generally associates with clinical outcomes better than serum creatinine-based eGFR (eGFRcr) despite similar precision in estimating measured GFR (mGFR). We sought to determine whether the risk of adverse outcomes with eGFRcr or eGFRcys was via GFR alone or also via non-GFR determinants among kidney transplant recipients. METHODS: Consecutive adult kidney transplant recipients underwent a standardized GFR assessment during a routine follow-up clinic visit between 2011 and 2013. Patients were followed for graft failure or the composite outcome of cardiovascular (CV) events or mortality through 2020. The risk of these events by baseline mGFR, eGFRcr and eGFRcys was assessed unadjusted, adjusted for mGFR and adjusted for CV risk factors. RESULTS: There were 1135 recipients with a mean baseline mGFR of 55.6, eGFRcr of 54.8 and eGFRcys of 46.8 ml/min/1.73 m2 and a median follow-up of 6 years. Each 10 ml/min/1.73 m2 decrease in mGFR, eGFRcr or eGFRcys associated with graft failure [hazard ratio (HR) 1.79, 1.68 and 2.07, respectively; P < .001 for all) and CV events or mortality outcome (HR 1.28, 1.19 and 1.43, respectively; P < .001 for all). After adjusting for mGFR, eGFRcys associated with graft failure (HR 1.57, P < .001) and CV events or mortality (HR 1.49, P < .001), but eGFRcr did not associate with either. After further adjusting for CV risk factors, risk of these outcomes with lower eGFRcys was attenuated. CONCLUSION: eGFRcr better represents the true relationship between GFR and outcomes after kidney transplantation because it has less non-GFR residual association. Cystatin C is better interpreted as a nonspecific prognostic biomarker than is eGFR in the kidney transplant setting.

Clinical Outcomes and Histological Patterns in Oxalate Nephropathy due to Enteric and Nonenteric Risk Factors.

INTRODUCTION: Current knowledge of risk factors and renal histologic patterns of oxalate nephropathy (ON) not due to primary hyperoxaluria (PH) has been limited to small case series and case reports. Thus, we analyzed and compared clinical risk factors, histologic characteristics, and renal outcomes of patients with biopsy-confirmed ON among a cohort of patients with enteric and nonenteric risk factors. METHODS: A clinical data repository of native kidney pathology reports from 2009 to 2020 at all Mayo Clinic sites was used to identify 421 ON cases. RESULTS: After excluding cases in transplanted kidneys or due to PH, 64 cases remained. Enteric risk factors were present in 30 and nonenteric in 34. Roux-en-Y gastric bypass (17) and pancreatic insufficiency (6) were most common in the enteric hyperoxaluria group. In the nonenteric group, vitamin C (7) and dietary oxalate (7) were common, while no apparent risk was noted in 16. Acute kidney injury (AKI) stage III at the time of diagnosis was present in 60%, and 40.6% required dialysis. Patients in the nonenteric group had more interstitial inflammation (p = 0.01), and a greater number of tubules contained intratubular calcium oxalate (CaOx) crystals (p = 0.001) than the nonenteric group. Patients in the enteric group were more likely to have baseline chronic kidney disease (CKD) (p = 0.02) and moderate-to-severe tubulointerstitial fibrosis and atrophy (IFTA) (OR 3.49, p = 0.02). After a median follow-up of 10 months, 39% were dialysis dependent, 11% received a kidney transplant, and 32% died. On univariate analysis, >10 tubules with CaOx crystals, baseline CKD, and AKI requiring dialysis correlated with the risk of dialysis, transplant, or death. On multivariate analysis, only AKI requiring dialysis correlated with adverse renal outcomes. CONCLUSION: This is the largest cohort study of ON not due to PH. Histologic features differ in patients with enteric versus nonenteric risks. Patients in the enteric group are more likely to have baseline CKD and significant IFTA, while patients in the nonenteric group were more likely to have a greater number of tubules with CaOx crystals and corresponding interstitial inflammation. AKI requiring dialysis at the time of diagnosis was the single most significant predictor of adverse renal outcome.

The impact of phone counseling on urinary stone prevention.

OBJECTIVE: We compared the effect of standard office-based consultation (OC) and phone correspondences (PC) on dietary 24-h urinary parameters. METHODS: The medical record of all patients treated between January and April 2019 was reviewed. Only patients who had at least two consecutive 24-h urine collections were included. Linear and logistic regressions were used to investigate the difference between the changes in urinary parameters after OC and PC. RESULTS: Forty-three patients underwent 135 OC and 34 PC. Twenty-one received OC and PC, and 22 had only OC. Gender, age, the distance to stone clinic, the number of previous stone episodes, and baseline urinary parameters were similar between the groups. Patients who had both OC and PC had a longer follow-up time (51.7 vs 18.5 months, p < 0.0001) as well as more consults (Median 5.4 vs 2.5, p < 0.0001). Six (27%) patients who had only OC, and eight (38%) patients who had both OC and PC, experienced stone recurrence during the study period (p = 0.52). Following PC, there was a greater improvement in urine volume in comparison to OC (0.27 l/day vs -0.06 l/day, p = 0.034), but there was no difference in the absolute values after the consults between the groups. CONCLUSION: In established stone-clinic patients, PC was associated with a better adherence with follow-up. The 24-h urine results were similar between PC and OC. PC may be an effective alternative for urinary stone management.

Subtyping Hyperchloremia among Hospitalized Patients by Machine Learning Consensus Clustering.

Background and Objectives: Despite the association between hyperchloremia and adverse outcomes, mortality risks among patients with hyperchloremia have not consistently been observed among all studies with different patient populations with hyperchloremia. The objective of this study was to characterize hyperchloremic patients at hospital admission into clusters using an unsupervised machine learning approach and to evaluate the mortality risk among these distinct clusters. Materials and Methods: We performed consensus cluster analysis based on demographic information, principal diagnoses, comorbidities, and laboratory data among 11,394 hospitalized adult patients with admission serum chloride of >108 mEq/L. We calculated the standardized mean difference of each variable to identify each cluster's key features. We assessed the association of each hyperchloremia cluster with hospital and one-year mortality. Results: There were three distinct clusters of patients with admission hyperchloremia: 3237 (28%), 4059 (36%), and 4098 (36%) patients in clusters 1 through 3, respectively. Cluster 1 was characterized by higher serum chloride but lower serum sodium, bicarbonate, hemoglobin, and albumin. Cluster 2 was characterized by younger age, lower comorbidity score, lower serum chloride, and higher estimated glomerular filtration (eGFR), hemoglobin, and albumin. Cluster 3 was characterized by older age, higher comorbidity score, higher serum sodium, potassium, and lower eGFR. Compared with cluster 2, odds ratios for hospital mortality were 3.60 (95% CI 2.33-5.56) for cluster 1, and 4.83 (95% CI 3.21-7.28) for cluster 3, whereas hazard ratios for one-year mortality were 4.49 (95% CI 3.53-5.70) for cluster 1 and 6.96 (95% CI 5.56-8.72) for cluster 3. Conclusions: Our cluster analysis identified three clinically distinct phenotypes with differing mortality risks in hospitalized patients with admission hyperchloremia.

Does bladder stone composition predict kidney stone composition?

INTRODUCTION Bladder stones have historically been associated with urinary stasis secondary to bladder outlet obstruction (BOO). Recent studies indicate that the role of BOO in bladder stone formation is minor. We evaluate the role of urinary lithogenic factors in bladder stone formation by comparing the compositions of bladder stones and kidney stones in patients with multi-site urinary calculi. MATERIALS AND METHODS: We identified patients who were treated for concomitant bladder stones and kidney stones between 2008-2019, and had both stone compositions available. Patients with bladder stone size < 10 mm, urinary foreign bodies, encrusted stents or tumors were excluded. Data regarding urinary symptoms, residual volumes, stone composition and 24-hours urine data were collected. RESULTS: We identified 40 males with a median age of 72 years (IQR 6-14), median residual volume of 76 mL (IQR 41-200), and a median prostate volume of 52 mL (IQR 32-102). Bladder outlet procedures were performed concomitantly with cystolitholapaxy in 21 (53%) patients. The most common bladder stone and kidney stone compositions were CaOx (47.5% and 65%), uric acid (32.5% and 22.5%), calcium phosphate (15% and 10%), and struvite (5% and 2.5%), respectively. Bladder stone and kidney stone compositions were identical in 70% of patients. Bladder stone composition was predictive of kidney stone composition, regardless of the PVR, bladder stone size, or whether an outlet procedure was performed. CONCLUSION: We found a high concordance between bladder stone and kidney stone composition, suggesting that metabolic abnormalities have a significant role in bladder stone formation. Bladder stone composition can be used to guide surgical and medical treatment for kidney stones in metabolically active stone patients.

Cardiac Troponin T and Right Ventricular Systolic Pressure Predict Cardiovascular and Mortality Risk in Kidney Transplant Candidates.

BACKGROUND: Patients presenting for kidney transplant (KTx) evaluation are subject to high rates of mortality and cardiovascular (CV) events pre- and post-KTx. CV and mortality risk assessment is needed. METHODS: We evaluated cardiac troponin T (cTnT) as a predictor of CV events and mortality in a racially diverse cohort with significant CV disease burden presenting for KTx evaluation. Right ventricular systolic pressure (RVSP) was also assessed in predicting these outcomes. The population consisted of 561 patients presenting for KTx evaluation from 2011 to 2013 at Mayo Clinic, Arizona. A cutoff value for cTnT and RVSP that was most associated with CV events or mortality was derived. Multivariate Cox regression analysis was used to assess cTnT, RVSP, traditional, and other risk factors for the outcomes of interest. RESULTS: Mean age was 53.5 ± 13.7 years and the median follow-up after KTx evaluation was 48.0 months. The cohort was 70.6% (n = 392) White, 11.4% (n = 63) Black, 8.5% (n = 47) Native American, and 3.1% (n = 17) Asian. Preexisting CV disease at the time of evaluation was prevalent in 24.4% (n = 137) of patients. During follow-up, 66.3% (n = 372) received a KTx and 21.9% (n = 123) had a composite event (16.8% death, 6.6 % CV events). It was found that 70.7% (n = 87) of events occurred in patients who were not transplanted; 53.5% (n = 300) had an elevated cTnT (≥0.01 ng/mL, median 0.02 ng/mL) and 84.1% (n = 344) of patients with RVSP data had an elevated RVSP (>25 mm Hg). Time to event analysis identified a cTnT ≥0.036 ng/mL and RVSP ≥31 mm Hg to be best predictive of CV events and mortality. Smoking, CV disease, hypoalbuminemia, RVSP, and cTnT independently predicted CV events and mortality. CONCLUSION: Elevated cTnT and RVSP were independently predictive of CV events and mortality in the cohort. Clinicians should consider the value of RVSP and cTnT as markers of CV risk in KTx evaluation.

Cardiac Troponin T Risk Stratification Model Predicts All-Cause Mortality Following Kidney Transplant.

BACKGROUND: We evaluated the role of increased cardiac troponin T (cTnT), vascular, and cardiac diseases in predicting 5 and 10-year all-cause mortality after kidney transplantation. METHODS: We reviewed a cohort of 764 kidney transplant recipients and analyzed pertinent cardiovascular risk factors at the time of transplant evaluation. Proportional hazards regression analysis with bootstrapping method was utilized to provide a risk stratification score for mortality. RESULTS: Mean age was 58.8 years (SD 12.1) and median follow-up was 7.0 years (range 1 day to 18.0 years). Fifty-four percent of patients (n = 415) had cTnT measured (median 0.02 ng/mL, range 0.01-4.91). Fifty-three percent (n = 407) had vascular disease, 59% (n = 448) had diabetes, and 44% (n = 336) had cardiac disease pre-transplant. Sixty percent (n = 460) required dialysis. Older age, increased cTnT, pre-transplant vascular and cardiac diseases predicted mortality in multivariate analysis. We derived 2 scoring systems with and without cTnT - the ACV and ACTV scores (age, cardiac disease, elevated cTnT, and vascular disease) - as predictors of mortality after kidney transplant. Point assignments were: age 60-69 years (1), age ≥70 years (2), cardiac disease (1), cTnT ≥0.04 ng/mL (1), and vascular disease (1). Both scoring systems significantly predicted mortality. The ACTV score better delineated risk stratification across score levels (0-2, 3-4, and 5 points). CONCLUSIONS: We developed a risk schema predictive of all-cause mortality after kidney transplant in a derivation cohort. The ACTV score, including an elevated cTnT, provided superior prediction compared to a scoring system without cTnT. Further studies to validate these findings are needed.

Antinuclear Antibody-Negative Lupus Nephritis with Full House Nephropathy: A Case Report and Review of the Literature.

Lupus nephritis (LN) is a serious and common complication of systemic lupus erythematosus (SLE) that predisposes to significant morbidity and mortality. Studies show that prompt diagnosis and treatment improves patient survival. We present a case of a 49-year-old female with an atypical presentation of LN who initially presented with new-onset hypertension, edema, arthritis, serositis and recently diagnosed leukocytoclastic vasculitis who later developed acute kidney injury, hematuria and nephrotic syndrome. Laboratory testing showed mixed cryoglobulinemia and elevated perinuclear anti-neutrophil cytoplasmic (p-ANCA) and myeloperoxidase (MPO) antibodies. SLE-related serologies were negative. Kidney biopsy showed diffuse proliferative global glomerulonephritis with a full-house nephropathy pattern on immunofluorescence suggestive of LN. Due to high clinical suspicion and renal biopsy findings, she was treated for LN with prompt renal response to immunosuppression. Cryoglobulins, p-ANCA and MPO titers normalized and the negative SLE serologies remained negative. Literature review on antinuclear antibody (ANA)-negative and seronegative LN revealed the following patient presentations: (1) renal-limited or renal and extra-renal manifestations of SLE with negative serologies and (2) renal and extra-renal manifestations of SLE with negative serologies at presentation who develop positive serologies later in follow-up. Both groups represent a unique and challenging cohort of patients who may require longer follow-up and further testing to rule out other glomerular diseases that may mimic LN on renal biopsy. The absence of SLE-related serologies should be weighed against a high pre-test probability of ANA-negative or seronegative LN. If highly suspected, the patient should be treated promptly with close monitoring.

Enhanced posttransplant management of patients with diabetes improves patient outcomes.

The survival of patients with diabetes mellitus in the general population has improved in recent years. Here we assessed whether similar trends have occurred in 1688 kidney recipients, including 413 with diabetes prior to transplant between 1996 and 2007. Compared to patients without diabetes, the 5-year mortality was significantly increased (hazard ratio (HR) 2.68 (1.95-3.69)) due to higher cardiovascular-, infection-, and malignancy-related deaths in those with diabetes. However, 5-year mortality in patients with diabetes significantly declined over time (HR 0.883 (0.817-0.954)), narrowing the mortality difference between patients with and those without diabetes and in more recent years largely eliminating it. Post transplant, patients with diabetes experienced a significant decline in major fatal/nonfatal cardiac events (HR 0.853 (0.782-0.930)) and infectious deaths over time. In contrast, neither cardiac events nor overall mortality declined in recipients without diabetes. The decline in mortality due to diabetes did not relate to a reduced pretransplant risk profile and was independent of posttransplant variables. The use of cardioprotective medications and glycemic control improved over time post transplant. Furthermore, graft function and serum albumin significantly improved over time and these parameters related to better survival (albumin, HR 0.365 (0.223-0.599); eGFR, HR 0.803 (0.756-0.852)). Thus, survival of kidney recipients with diabetes mellitus has improved markedly since 1996 likely reflecting, at least in part, enhanced posttransplant management and outcomes.

Proliferative glomerulonephritis due to monoclonal deposition with organized substructures.

A growing number of monoclonal gammopathy-associated kidney diseases recently have been recognized. We present the case of a 54-year-old man who presented with acute kidney injury and hypocomplementemia. Kidney biopsy confirmed the presence of immunoglobulin G κ pseudothrombi with intracytoplasmic crystals in glomeruli and tubules. Levels of κ free light chains were elevated without a detectable monoclonal gammopathy, and bone marrow biopsy results were normal. After the first course of rituximab, cyclophosphamide, and dexamethasone in addition to daily plasmapheresis, kidney function recovered within 2 weeks and dialysis therapy was discontinued. Treatment for monoclonal protein-induced kidney disease should be considered in the setting of progressive decreased kidney function, even in the absence of a circulating monoclonal protein or cellular clone of origin.

Vitamin D deficiency, parathyroid hormone levels, and bone disease among patients with end-stage liver disease and normal serum creatinine awaiting liver transplantation.

UNLABELLED: Vitamin D deficiency is common among patients with end-stage liver disease (ESLD). The primary aim of our study was to assess the prevalence of vitamin D deficiency, secondary hyperparathyroidism, and bone disease in patients with ESLD awaiting LT. METHODS: We retrospectively studied 190 patients at our center. Serum total 25-hydroxyvitamin D (25-OH D), parathyroid hormone (PTH), calcium, and bone mineral analysis (BMA) were recorded. Standard World Health Organization (WHO) criteria were used to diagnose osteopenia/osteoporosis. Only patients with normal serum creatinine were analyzed. RESULTS: Thirty-two of 190 patients were excluded from the final analysis (missing serum total 25-OH D levels in three patients and elevated serum creatinine, 29 patients). 105 of 158 (66.4%) evaluable patients had 25-OH D levels <25 ng/mL. Patients included in the analysis (n = 158) were divided according to serum total 25-OH D levels: 0-10 ng/mL (n = 23), 11-20 ng/mL (n = 64), and >20 ng/mL (n = 71). There were no significant differences in mean serum PTH and corrected calcium levels among the three subgroups. Only three patients had elevated serum PTH. Patients with total 25-OH D ≤ 10 ng/mL had higher model for end-stage liver disease (MELD) scores vs. those with 25-OH D > 20 ng/mL (13.3 ± 3, range 8-21, vs. 11.9 ± 3.4, range 6-29, p = 0.004). Irrespective of vitamin D status, bone disease was present in 64.6% of patients. CONCLUSION: Low vitamin D levels and bone disease are common among patients with ESLD awaiting LT. Despite a high prevalence of low serum total 25-OH D, our cohort maintained normal corrected calcium levels and did not develop secondary hyperparathyroidism. We propose that free serum 25-OH D and vitamin D-binding protein may be necessary to accurately establish the diagnosis of vitamin D deficiency in the setting of ESLD. Additional studies are needed to further define mechanisms of bone disease in patients with ESLD.

A Student Teaching Assistant Program for Diversity, Equity, Inclusion, and Antiracism Curricular Enhancement.

PROBLEM: In the United States, physician bias is exhibited early in medical training and contributes to systemic inequities within the field of medicine. A lack of diversity, equity, inclusion, and antiracism (DEI-AR) content within medical curricula drives critical gaps in knowledge and deficiencies when preparing medical students to serve patients of diverse backgrounds. At the Mayo Clinic Alix School of Medicine (MCASOM), student-led curricular reviews between 2017 to 2018 and 2020 to 2021 revealed opportunities to improve DEI-AR content within preclinical courses. Course directors expressed concern of limited expertise and time to enact effective changes. APPROACH: The MCASOM DEI-AR teaching assistant (TA) program aims to curate a collaborative partnership between course directors and compensated student TAs to facilitate course enhancements responsive to the prior preclinical course review while centering standardized DEI-AR best practices. OUTCOMES: As of January 2024, the program has engaged 14 TAs and partnered with 24 preclinical courses. Postcourse student evaluation responses were collected from 8 courses for 2021 to 2022 (before enhancements) and 2022 to 2023 (after enhancements). Student satisfaction with DEI-AR content is tracked through postcourse evaluations, with preliminary data demonstrating improvement after DEI-AR curricular integration (improvement of mean preenhancement and postenhancement scores of 3.81 to 4.05; t12 = 1.79, P = .21). Qualitative student comments were sorted into general categories of positive, negative, or neutral, showing a 6.25% median increase in positive perception of DEI. NEXT STEPS: Plans for the MCASOM DEI-AR TA program include application of quality improvement strategies to improve program processes and outcomes. Development of a centralized dashboard that integrates course enhancement progress and ongoing feedback from evaluations is anticipated to facilitate this effort. The program additionally aims to develop partnerships with clinical clerkships, which would allow for a more comprehensive enhancement of the overall medical education experience related to DEI-AR.

Nephrolithiasis and loss of kidney function.

PURPOSE OF REVIEW: The prevalence of nephrolithiasis has been on the rise over recent decades. There have also been extensive efforts to identify risk factors for chronic kidney disease (CKD). The purpose of this review is to highlight recent evidence on the association of nephrolithiasis with the development of CKD and end-stage renal disease (ESRD). RECENT FINDINGS: Several epidemiologic studies over the past decade assessed the relationship between history of nephrolithiasis and CKD. Across several studies, patients with nephrolithiasis had about a two-fold higher risk for decreased renal function or need for renal replacement therapy. This risk appears to be independent of risk factors for CKD that are common in stone formers such as hypertension and diabetes mellitus. Specific risk factors for CKD in stone formers include recurrent urinary tract infections, struvite and possibly uric acid stone composition, symptomatic stones, solitary kidney, ileal conduit, neurogenic bladder, and hydronephrosis. SUMMARY: Recent evidence has shown a consistent relationship between nephrolithiasis history and an increased risk of CKD and ESRD. Understanding the characteristics that predispose to CKD may better inform how to optimally manage patients with nephrolithiasis and prevent this complication.

Acute kidney injury is an independent marker of severity in Clostridium difficile infection: a nationwide survey.

GOALS: To examine clinical outcomes in hospitalized Clostridium difficile infection (CDI) patients with acute kidney injury (AKI) using the National Hospital Discharge Survey for 2005 to 2009. BACKGROUND: CDI can cause serious complications in hospitalized adults. On the basis of expert opinion, guidelines recommend AKI as a marker of severe CDI, but this has not been extensively validated. MATERIALS AND METHODS: CDI and AKI patients were identified using International Classification of Diseases 9th edition codes. Weighted data analyses were performed to provide national estimates and compare outcomes in patients with AKI and CDI to CDI patients without AKI. RESULTS: There were an estimated 1,261,712 patients with CDI identified with a median age of 75 years; 59.2% were female and 17.5% developed AKI. On multiple variable analysis, after adjusting for age, sex, and comorbid conditions, AKI was independently associated with length of hospital stay increase by 1.9 days, risk of colectomy with an odds ratio (OR) of 1.35, all-cause in-hospital mortality (OR, 2.76), and dismissal to a care facility (OR, 1.43), all P<0.0001. CONCLUSIONS: These data support prior consensus opinion that AKI is an independent marker associated with adverse outcomes in CDI and provides key prognostic information.

Safety and mortality outcomes for direct oral anticoagulants in renal transplant recipients.

PURPOSE: Direct oral anticoagulants (DOACs) are increasingly used in renal transplant recipients (RTR), but relatively understudied in this population. We assess the safety of post-transplant anticoagulation with DOACs compared to warfarin. METHODS: We conducted a retrospective study of RTRs at the Mayo Clinic sites (2011-present) that were anticoagulated for greater than 3 months excluding the 1st month post-transplant. The main safety outcomes were bleeding and all-cause mortality. Concomitant antiplatelet and interacting drugs were noted. DOAC dose adjustment was assessed according to common US prescribing practices, guidelines, and/or FDA labeling. RESULTS: The median follow-up was longer for RTRs on warfarin (1098 days [IQR 521, 1517]) than DOACs (449 days [IQR 338, 942]). Largely, there were no differences in baseline characteristics and comorbidities between RTRs on DOACs (n = 208; apixaban 91.3%, rivaroxaban 8.7%) versus warfarin (n = 320). There was no difference in post-transplant use of antiplatelets, immunosuppressants, most antifungals assessed, or amiodarone. There was no significant difference in incident major bleeding (8.4 vs. 5.3%, p = 0.89), GI bleeding (4.4% vs. 1.9%, p = 0.98), or intra-cranial hemorrhage (1.9% vs. 1.4%, p = 0.85) between warfarin and DOAC. There was no significant difference in mortality in the warfarin group compared to DOACs when adjusted for follow-up time (22.2% vs. 10.1%, p = 0.21). Rates of post-transplant venous thromboembolism, atrial fibrillation or stroke were similar between the two groups. 32% (n = 67) of patients on DOACs were dose reduced, where 51% of those reductions were warranted. 7% of patients that were not dose reduced should have been. CONCLUSIONS: DOACs did not have inferior bleeding or mortality outcomes compared to warfarin in RTRs. There was greater use of warfarin compared to DOACs and a high rate of improper DOAC dose reduction.

The Value of Pharmacogenomics for White and Indigenous Americans after Kidney Transplantation.

BACKGROUND: There is a paucity of evidence to inform the value of pharmacogenomic (PGx) results in patients after kidney transplant and how these results differ between Indigenous Americans and Whites. This study aims to identify the frequency of recommended medication changes based on PGx results and compare the pharmacogenomic (PGx) results and patients' perceptions of the findings between a cohort of Indigenous American and White kidney transplant recipients. METHODS: Thirty-one Indigenous Americans and fifty White kidney transplant recipients were studied prospectively. Genetic variants were identified using the OneOme RightMed PGx test of 27 genes. PGx pharmacist generated a report of the genetic variation and recommended changes. Pre- and post-qualitative patient surveys were obtained. RESULTS: White and Indigenous American subjects had a similar mean number of medications at the time of PGx testing (mean 13 (SD 4.5)). In the entire cohort, 53% received beta blockers, 30% received antidepressants, 16% anticoagulation, 47% pain medication, and 25% statin therapy. Drug-gene interactions that warranted a clinical action were present in 21.5% of patients. In 12.7%, monitoring was recommended. Compared to the Whites, the Indigenous American patients had more normal CYP2C19 (p = 0.012) and CYP2D6 (p = 0.012) activities. The Indigenous American patients had more normal CYP4F2 (p = 0.004) and lower VKORC (p = 0.041) activities, phenotypes for warfarin drug dosing, and efficacy compared to the Whites. SLC6A4, which affects antidepressant metabolism, showed statistical differences between the two cohorts (p = 0.017); specifically, SLC6A4 had reduced expression in 45% of the Indigenous American patients compared to 20% of the White patients. There was no significant difference in patient perception before and after PGx. CONCLUSIONS: Kidney transplant recipients had several drug-gene interactions that were clinically actionable; over one-third of patients were likely to benefit from changes in medications or drug doses based on the PGx results. The Indigenous American patients differed in the expression of drug-metabolizing enzymes and drug transporters from the White patients.