Phase I clinical trial of the feasibility and safety of direct peritoneal resuscitation in liver transplantation.

BACKGROUND: Direct peritoneal resuscitation (DPR) is associated with improved outcomes in trauma. Animal models suggest DPR has favorable effects on the liver. We sought to evaluate its safety and assess for improved outcomes in liver transplantation (LT). METHODS: LT patients with renal dysfunction and/or obesity were enrolled in a phase-I clinical trial. DPR lasted 8-24 â€‹h depending on postoperative disposition. Primary outcome was percent of patients completing DPR. Secondary outcomes evaluated complications. Controls with either obesity (control-1) or both risk factors (obesity â€‹+ â€‹renal dysfunction, control-2) were analyzed. RESULTS: Fifteen patients were enrolled (seven with both criteria and eight with obesity alone). DPR was completed in 87 â€‹% of patients, with one meeting stopping criteria. Controls included 45 (control-1) and 24 (control-2) patients. Return to operating room, graft loss, and late infections were lower with DPR. CONCLUSION: DPR appears to be safe in closed abdomens following LT, warranting a follow-up phase-II trial to assess efficacy.

A Mediterranean diet plan in lactating women with obesity reduces maternal energy intake and modulates human milk composition - a feasibility study.

Introduction: Maternal obesity is associated with increased concentrations of human milk (HM) obesogenic hormones, pro-inflammatory cytokines, and oligosaccharides (HMOs) that have been associated with infant growth and adiposity. The objective of this pilot study was to determine if adherence to a Mediterranean meal plan during lactation modulates macronutrients and bioactive molecules in human milk from mothers with obesity. Methods: Sixteen healthy, exclusively breastfeeding women with obesity (body mass index ≥30 kg/m2) enrolled between 4 and 5 months postpartum. The women followed a 4-week Mediterranean meal plan which was provided at no cost. Maternal and infant anthropometrics, HM composition, and infant intakes were measured at enrollment and at weeks 2 and 4 of the intervention. Thirteen mother-infant dyads completed the study. Additionally, participants from an adjacent, observational cohort who had obesity and who collected milk at 5 and 6 months postpartum were compared to this cohort. Results: Participants' healthy eating index scores improved (+27 units, p < 0.001), fat mass index decreased (-4.7%, p < 0.001), and daily energy and fat intake were lower (-423.5 kcal/day, p < 0.001 and-32.7 g/day, p < 0.001, respectively) following the intervention. While HM macronutrient concentrations did not change, HM leptin, total human milk oligosaccharides (HMOs), HMO-bound fucose, Lacto-N-fucopentaose (LNFP)-II, LNFP-III, and difucosyllacto-N-tetrose (DFLNT) concentrations were lower following the intervention. Infant intakes of leptin, tumor necrosis factor (TNF)-α, total HMOs, HMO-bound fucose, LNFP-III and DFLNT were lower following the intervention. Specific components of the maternal diet (protein and fat) and specific measures of maternal diet quality (protein, dairy, greens and beans, fruit and vegetables) were associated with infant intakes and growth. Discussion: Adherence to a Mediterranean meal plan increases dietary quality while reducing total fat and caloric intake. In effect, body composition in women with obesity improved, HM composition and infants' intakes were modulated. These findings provide, for the first time, evidence-based data that enhancing maternal dietary quality during lactation may promote both maternal and child health. Longer intervention studies examining the impact of maternal diet quality on HM composition, infant growth, and infant development are warranted.

Fibrinolysis Resistance After Injury Is a Risk Factor for a Hospital-Acquired Pneumonia-Like Disease Pattern.

Background: Pneumonia is associated with increased morbidity and costs in the intensive care unit (ICU). Its early identification is key for optimal outcomes, but early biomarkers are lacking. Studies suggest that fibrinolysis resistance (FR) after major abdominal surgery is linked to an increased risk of infection. Patients and Methods: Patients in a randomized controlled trial for hemorrhagic shock were evaluated for FR. Fibrinolysis resistance was quantified by thrombelastography with exogenous tissue plasminogen activator (tPA-TEG) at 24- and 48-hours post-injury and measuring LY30 (%). A receiver-operating characteristics (ROC) curve analysis was used to identify a cutoff for increased risk of pneumonia, which was then validated in ICU patients at risk for venous thromboembolism (VTE). Multivariable logistic regression was used to control for confounders. Results: Forty-nine patients in the hemorrhagic shock cohort had tPA-TEGs at 24- and 48-hours (median ISS, 27; 7% pneumonia). A composite tPA-TEG LY30 of less than 4% at 24 and 48 hours was found to be the optimal cutoff for increased risk of pneumonia. This cohort had a seven-fold increased rate of pneumonia (4% vs. 28%; p = 0.048). Eighty-eight patients in the VTE cohort had tPA-TEGs at 24 and 48 hours post-ICU admission (median ISS, 28; 6% pneumonia). The tPA-TEG LY30 of less than 4% was associated with a 10-fold increased rate of pneumonia (19% vs. 1.5%; p = 0.002). In patients with traumatic brain injury, the same association was found (33% vs. 3.2%; p = 0.006). Adjusting for confounders, the tPA-TEG persisted as a substantial risk factor for pneumonia (adjusted odds ratio [OR], 35.7; 95% confidence interval [CI], 1.9-682; p = 0.018). Conclusions: Fibrinolysis resistance quantified by tPA-TEG within 48 hours of ICU admission is associated with an increased risk of pneumonia in patients in hemorrhagic shock and those at risk for VTE. Prospective validation of the tPA-TEG LY30 optimal cutoff for pneumonia and further investigation into whether endogenous FR is a cause of an altered immunity is warranted.

Differential in Kidney Graft Years on the Basis of Solitary Kidney, Simultaneous Liver-Kidney, and Kidney-after-Liver Transplants.

BACKGROUND: The number of simultaneous liver-kidney (SLK) transplants has significantly increased in the United States. There has also been an increase in kidney-after-liver transplants associated with 2017 policy revisions aimed to fairly allocate kidneys after livers. SLK and kidney-after-liver candidates are prioritized in allocation policy for kidney offers ahead of kidney-alone candidates. METHODS: We compared kidney graft outcomes of kidney-alone transplant recipients with SLK and kidney-after-liver transplants using paired kidney models to mitigate differences among donor risk factors. We evaluated recipient characteristics between transplant types and calculated differential graft years using restricted mean survival estimates. RESULTS: We evaluated 3053 paired donors to kidney-alone and SLK recipients and 516 paired donors to kidney-alone and kidney-after-liver recipients from August 2017 to August 2022. Kidney-alone recipients were younger, more likely on dialysis, and Black race. One-year and 3-year post-transplant kidney graft survival for kidney-alone recipients was 94% and 86% versus SLK recipients 89% and 80%, respectively, P < 0.001. One-year and 3-year kidney graft survival for kidney-alone recipients was 94% and 84% versus kidney-after-liver recipients 93% and 87%, respectively, P = 0.53. The additional kidney graft years for kidney-alone versus SLK transplants was 21 graft years/100 transplants (SEM=5.0) within 4 years post-transplantation, with no significant difference between kidney-after-liver and kidney-alone transplants. CONCLUSIONS: Over a 5-year period in the United States, SLK transplantation was associated with significantly lower kidney graft survival compared with paired kidney-alone transplants. Most differences in graft survival between SLK and kidney-alone transplants occurred within the first year post-transplantation. By contrast, kidney-after-liver transplants had comparable graft survival with paired kidney-alone transplants.

Reassessing the survival benefit of deceased donor liver transplantation: retrospective cohort study.

INTRODUCTION: Currently in the United States, deceased donor liver transplant (DDLT) allocation priority is based on the model for end-stage liver disease including sodium (MELD-Na) score. The United Network for organ sharing's 'Share-15' policy states that candidates with MELD-Na scores of 15 or greater have priority to receive local organ offers compared to candidates with lower MELD-Na scores. Since the inception of this policy, major changes in the primary etiologies of end-stage liver disease have occurred and previous assumptions need to be recalibrated. METHODS: The authors retrospectively analyzed the Scientific Registry of Transplant Recipients database between 2012 and 2021 to determine life years saved by DDLT at each interval of MELD-Na score and the time-to-equal risk and time-to-equal survival versus remaining on the waitlist. The authors stratified our analysis by MELD exception points, primary disease etiology, and MELD score. RESULTS: On aggregate, compared to remaining on the waitlist, a significant 1-year survival advantage of DDLT at MELD-Na scores as low as 12 was found. The median life years saved at this score after a liver transplant was estimated to be greater than 9 years. While the total life years saved were comparable across all MELD-Na scores, the time-to-equal risk and time-to-equal survival decreased exponentially as MELD-Na scores increased. CONCLUSION: Herein, the authors challenge the perception as to the timing of DDLT and when that benefit occurs. The national liver allocation policy is transitioning to a continuous distribution framework and these data will be instrumental to defining the attributes of the continuos allocation score.

A model for calculating the long-term estimated post-transplant survival of deceased donor liver transplant patients.

BACKGROUND: The estimated long-term survival (EPTS) score is used for kidney allocation. A comparable prognostic tool to accurately quantify EPTS benefit in deceased donor liver transplant (DDLT) candidates is nonexistent. METHODS: Using the Scientific Registry of Transplant Recipients (SRTR) database, we developed, calibrated, and validated a nonlinear regression equation to calculate liver-EPTS (L-EPTS) for 5- and 10-year outcomes in adult DDLT recipients. The population was randomly split (70:30) into two discovery (N = 26,372 and N = 46,329) and validation cohorts (N = 11,288 and N = 19,859) for 5- and 10-year post-transplant outcomes, respectively. Discovery cohorts were used for variable selection, Cox proportional hazard regression modeling, and nonlinear curve fitting. Eight clinical variables were selected to construct the L-EPTS formula, and a five-tiered ranking system was created. FINDINGS: Tier thresholds were defined and the L-EPTS model was calibrated (R2 = 0.96 [5-year] and 0.99 [10-year]). Patients' median survival probabilities in the discovery cohorts for 5- and 10-year outcomes ranged from 27.94% to 89.22% and 16.27% to 87.97%, respectively. The L-EPTS model was validated via calculation of receiver operating characteristic (ROC) curves using validation cohorts. Area under the ROC curve was 82.4% (5-year) and 86.5% (10-year). INTERPRETATION: L-EPTS has high applicability and clinical utility because it uses easily obtained pre-transplant patients characteristics to accurately discriminate between those who are likely to receive a prolonged survival benefit and those who are not. It is important to evaluate medical urgency alongside survival benefit and placement efficiency when considering the allocation of a scarce resource. FUNDING: There are no funding sources related to this project.

Postoperative fibrinolytic resistance is associated with early allograft dysfunction in liver transplantation: A prospective observational study.

Perioperative dysfunction of the fibrinolytic system may play a role in adverse outcomes for liver transplant recipients. There is a paucity of data describing the potential impact of the postoperative fibrinolytic system on these outcomes. Our objective was to determine whether fibrinolysis resistance (FR), on postoperative day one (POD-1), was associated with early allograft dysfunction (EAD). We hypothesized that FR, quantified by tissue plasminogen activator thrombelastography, is associated with EAD. Tissue plasminogen activator thrombelastography was performed on POD-1 for 184 liver transplant recipients at a single institution. A tissue plasminogen activator thrombelastography clot lysis at 30 minutes of 0.0% was identified as the cutoff for FR on POD-1. EAD occurred in 32% of the total population. Fifty-nine percent (n=108) of patients were categorized with FR. The rate of EAD was 42% versus 17%, p <0.001 in patients with FR compared with those without, respectively. The association between FR and EAD risk was assessed using multivariable logistic regression after controlling for known risk factors. The odds of having EAD were 2.43 times (95% CI, 1.07-5.50, p =0.03) higher in recipients with FR [model C statistic: 0.76 (95% CI, 0.64-0.83, p <0.001]. An additive effect of receiving a donation after circulatory determination of death graft and having FR in the rate of EAD was observed. Finally, compared with those without FR, recipients with FR had significantly shorter graft survival time ( p =0.03). In conclusion, FR on POD-1 is associated with EAD and decreased graft survival time. Postoperative viscoelastic testing may provide clinical utility in identifying patients at risk for developing EAD, especially for recipients receiving donation after circulatory determination of death grafts.

Preliminary safety and efficacy of laser stricturotomy for treatment of refractory biliary anastomotic strictures following liver transplantation.

Biliary anastomotic stricture (BAS) is a frequent complication of liver transplantation and is associated with reduced graft survival and patient morbidity. Existing treatments for BAS involve dilation of the stricture though placement of 1 or more catheters for 6 to 24 months yielding limited effectiveness in transplant patients. In this case series, we present preliminary safety and efficacy of a novel percutaneous laser stricturotomy treatment in a cohort of 5 posttransplant patients with BAS refractory to long-term large bore catheterization. In all patients, holmium or thulium laser was used to excise the stricture and promote biliary re-epithelization. There were no periprocedural complications. Technical success was 100% and at mean follow-up time of 22 months, there have been no recurrences. In conclusion, percutaneous laser stricturotomy demonstrates preliminary safety and efficacy in treatment of refractory BAS following liver transplantation.

Prevalence and progression of intraductal papillary mucinous neoplasms of the pancreas in solid organ transplant recipients: A systematic review.

Solid organ transplantation (SOT) recipients are known to carry an increased risk of malignancy because of long-term immunosuppression. However, the progression of intraductal papillary mucinous neoplasm of the pancreas (IPMN) in this population remains unclear. We performed a systematic review by searching PubMed, Embase, Scopus, and Google Scholar. All studies containing IPMNs in solid organ transplantation recipients were screened. We included 11 studies in our final analysis, totaling 274 patients with IPMNs of the 8213 SOT recipients. The prevalence from 8 studies was 4.7% (95% CI 2.4%-7.7%) in a random-effects model with median study periods of 24 to 220 months. The median rate for all progressions from 10 studies was 20% (range, 0%-88%) within 13 to 41 months of the median follow-up time. By utilizing the results of 3 case-control studies, the relative risk from a random-effects model for progression (worrisome features and high-risk stigmata) of IPMNs was 0.39 (95% CI 0.12-1.31). No adenocarcinoma derived from IPMN was reported in the included studies. Overall, this study indicates that the progression of pretransplant IPMN does not increase drastically compared with the general nontransplant population. However, considering the limited literature, further studies are required for confirmation.

Practice patterns of the medical evaluation of living liver donors in the United States.

Living donor liver transplantation (LDLT) can help address the growing organ shortage in the United States, yet little is known about the current practice patterns in the medical evaluation of living liver donors. We conducted a 131-question survey of all 53 active LDLT transplant programs in the United States to assess current LDLT practices. The response rate was 100%. Donor acceptance rate was 0.33 with an interquartile range of 0.33-0.54 across all centers. Areas of high intercenter agreement included minimum age cutoff of 18 years (73.6%) and the exclusion of those with greater than Class 1 obesity (body mass index, 30.0-34.9 m/kg 2 ) (88.4%). Diabetes mellitus was not an absolute exclusion at most centers (61.5%). Selective liver biopsies were performed for steatosis or iron overload on imaging (67.9% and 62.3%, respectively) or for elevated liver enzymes (60.4%). Steatohepatitis is considered an exclusion at most centers (84.9%). The most common hypercoagulable tests performed were factor V Leiden (FVL) (88.5%), protein C (73.1%), protein S (71.2%), antithrombin III (71.2%) and prothrombin gene mutation (65.4%). At 41.5% of centers, donors were allowed to proceed with donation with FVL heterozygote status. Most programs discontinue oral contraceptive pills at least 28 days prior to surgery. At most centers, the need for cardiovascular ischemic risk testing is based on age (73.6%) and the presence of one or more cardiac risk factors (68.0%). Defining areas of practice consensus and variation underscores the need for data generation to develop evidence-based guidance for the evaluation and risk assessment of living liver donors.

An evaluation of the organ procurement and transplantation network's expanded post-transplant performance metrics.

On July 14, 2022, the Organ Procurement and Transplantation Network's (OPTN) Membership and Professional Standards Committee (MPSC) approved bylaws including two new post-transplant performance evaluation metrics, the 90-day (90D) and 1-year conditional on the 90-day (1YC90D) graft survival hazard ratio (HR). These metrics have replaced the previous 1-year (1Y) unconditional, post-transplant graft survival HR and are used to nationally rank and identify programs for MPSC review. The MPSC's policies have major implications for all transplant programs, providers, and patients across the United States. Herein we show two significant limitations with the new evaluation criteria, arbitrary censoring periods and interdependence in the new performance metrics. We have demonstrated a strong and consistent inverse correlation between the new evaluation metrics, thus proving a lack of independence. Moreover, these two evaluation criteria are interdependent even at nominal HRs. Thus, the 90D cohort can be used to accurately predict whether the 1YC90D is above or below a given HR threshold. This could alter practice behaviors and the timing of patient event reporting, which may result in many unintended consequences related to clinical practice. Here we provide the first evidence that this new evaluation system will lead to a significant increase in the number of programs flagged for MPSC review. When this occurs, the cost of operating a transplant program will increase without a clear demonstration of an increased accuracy in identifying problematic programs.

Survival Benefit of Living-Donor Liver Transplant.

Importance: Despite the acceptance of living-donor liver transplant (LDLT) as a lifesaving procedure for end-stage liver disease, it remains underused in the United States. Quantification of lifetime survival benefit and the Model for End-stage Liver Disease incorporating sodium levels (MELD-Na) score range at which benefit outweighs risk in LDLT is necessary to demonstrate its safety and effectiveness. Objective: To assess the survival benefit, life-years saved, and the MELD-Na score at which that survival benefit was obtained for individuals who received an LDLT compared with that for individuals who remained on the wait list. Design, Setting, and Participants: This case-control study was a retrospective, secondary analysis of the Scientific Registry of Transplant Recipients database of 119 275 US liver transplant candidates and recipients from January 1, 2012, to September 2, 2021. Liver transplant candidates aged 18 years or older who were assigned to the wait list (N = 116 455) or received LDLT (N = 2820) were included. Patients listed for retransplant or multiorgan transplant and those with prior kidney or liver transplants were excluded. Exposures: Living-donor liver transplant vs remaining on the wait list. Main Outcomes and Measures: The primary outcome of this study was life-years saved from receiving an LDLT. Secondary outcomes included 1-year relative mortality and risk, time to equal risk, time to equal survival, and the MELD-Na score at which that survival benefit was obtained for individuals who received an LDLT compared with that for individuals who remained on the wait list. MELD-Na score ranges from 6 to 40 and is well correlated with short-term survival. Higher MELD-Na scores (>20) are associated with an increased risk of death. Results: The mean (SD) age of the 119 275 study participants was 55.1 (11.2) years, 63% were male, 0.9% were American Indian or Alaska Native, 4.3% were Asian, 8.2% were Black or African American, 15.8% were Hispanic or Latino, 0.2% were Native Hawaiian or Other Pacific Islander, and 70.2% were White. Mortality risk and survival models confirmed a significant survival benefit for patients receiving an LDLT who had a MELD-Na score of 11 or higher (adjusted hazard ratio, 0.64 [95% CI, 0.47-0.88]; P = .006). Living-donor liver transplant recipients gained an additional 13 to 17 life-years compared with patients who never received an LDLT. Conclusions and Relevance: An LDLT is associated with a substantial survival benefit to patients with end-stage liver disease even at MELD-Na scores as low as 11. The findings of this study suggest that the life-years gained are comparable to or greater than those conferred by any other lifesaving procedure or by a deceased-donor liver transplant. This study's findings challenge current perceptions regarding when LDLT survival benefit occurs.

Infant intakes of human milk branched chain amino acids are negatively associated with infant growth and influenced by maternal body mass index.

BACKGROUND: Branched-chain amino acids (BCAAs: isoleucine, leucine, and valine) and aromatic amino acids (AAAs: phenylalanine and tyrosine) are hypothesized to influence early-life obesity risk. OBJECTIVE: To assess HM free amino acid (AA) concentrations and infant intakes of HM AAs from women with obesity (OB) compared to those with normal weight (NW) and determine the relationships between HM AA consumption and infant growth. METHODS: HM samples were collected at 0.5 (n = 151), 2 (n = 129), and 6 (n = 93) months postpartum from mothers with NW (body mass index [BMI] = 18.5-24.9 kg/m2 ) and OB (BMI > 30 kg/m2 ). HM AAs were quantified via mass spectrometry. Infant HM intake, anthropometrics and body composition were assessed. Linear mixed-effects models (LMEM) examined the relationships between maternal BMI and HM AA intakes, and HM AA intake and infant growth over the first 6 months postpartum after adjusting for maternal and infant characteristics. RESULTS: Maternal BMI was positively associated with infant intakes of isoleucine, leucine, and AAAs across timepoints. HM AA intakes were positively associated with weight-for-length z-score, fat mass index, and fat-free mass index in infants (p < 0.05). CONCLUSIONS: Maternal BMI led to differences in HM AA composition, which was associated with infant body composition.

Genomic markers associated with successful treatment of hypertension with lisinopril: A pilot study.

OBJECTIVE: To identify single nucleotide variants (SNVs) associated with lisinopril effectiveness. MATERIALS AND METHODS: This was an observational study using a candidate gene approach to examine SNVs associated with lisinopril effectiveness. Drug effectiveness was defined as 10% decrease in systolic blood pressure at 1 week follow-up. We used the Illumina GWAS MEGA chip to examine variants in the renin/angiotensin pathway that may be associated with drug effectiveness. RESULTS: 61 subjects were enrolled, and 33 (54.1%) were responsive to lisinopril therapy. SNVs in AGT (p = 0.0141), REN (p = 0.0192), and ACE2 (p = 0.0002) were found to be associated with successful treatment on lisinopril. Conclusion and relevance: SNVs in the renin and angiotensin pathway are associated with lisinopril effectiveness in a pilot cohort of patients with uncontrolled hypertension.

Human Milk Oligosaccharide Concentrations and Infant Intakes Are Associated with Maternal Overweight and Obesity and Predict Infant Growth.

Human milk oligosaccharides (HMOs) are bioactive molecules playing a critical role in infant health. We aimed to quantify the composition of HMOs of women with normal weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), or obesity (30.0-60.0 kg/m2) and determine the effect of HMO intake on infant growth. Human milk (HM) samples collected at 2 months (2 M; n = 194) postpartum were analyzed for HMO concentrations via high-performance liquid chromatography. Infant HM intake, anthropometrics and body composition were assessed at 2 M and 6 M postpartum. Linear regressions and linear mixed-effects models were conducted examining the relationships between maternal BMI and HMO composition and HMO intake and infant growth over the first 6 M, respectively. Maternal obesity was associated with lower concentrations of several fucosylated and sialylated HMOs and infants born to women with obesity had lower intakes of these HMOs. Maternal BMI was positively associated with lacto-N-neotetraose, 3-fucosyllactose, 3-sialyllactose and 6-sialyllactose and negatively associated with disialyllacto-N-tetraose, disialyllacto-N-hexaose, fucodisialyllacto-N-hexaose and total acidic HMOs concentrations at 2 M. Infant intakes of 3-fucosyllactose, 3-sialyllactose, 6-sialyllactose, disialyllacto-N-tetraose, disialyllacto-N-hexaose, and total acidic HMOs were positively associated with infant growth over the first 6 M of life. Maternal obesity is associated with changes in HMO concentrations that are associated with infant adiposity.

The Genomics of Elevated ALT and Adducts in Therapeutic Acetaminophen Treatment: a Pilot Study.

INTRODUCTION: Therapeutic acetaminophen (APAP) ingestion causes asymptomatic drug-induced liver injury in some patients. In most cases, elevations in alanine aminotransferase (ALT) are transient and return to the normal range, even with continued APAP ingestion, though ALT elevation persists in some patients unpredictably. The etiology of this liver injury or adaption is unclear. Our objective was to identify new pharmacogenomic variants associated with elevated ALT or elevated protein adduct concentrations in patients receiving therapeutic acetaminophen. METHODS: We performed genome-wide sequencing analysis on eight patients using leftover blood samples from an observational study that administered four grams of acetaminophen for up to 16 days to all patients. Two patients with ALT elevations > two times the upper limit of normal, two patients with no adduct formation, and four control patients were sequenced. The genomes were aligned with the GRCh38 reference sequence, and variants with predicted low, moderate, or high impact on the subsequent proteins were first manually curated for biologic plausibility, then organized and examined in the REACTOME pathway analysis program. RESULTS: We found 394 variants in 107 genes associated with elevated ALT. Variants associated with ALT elevation predominantly involved genes in the immune system (MHC class II complex genes), endoplasmic reticulum stress response (SEC23B and XBP1), oxidative phosphorylation (NDUFB9), and WNT/beta-catenin signaling (FZD5). Variants associated with elevated adducts were primarily in signal transduction (MUC20) and DNA repair mechanisms (P53). CONCLUSIONS: While underpowered, genetic variants in immune system genes may be associated with drug-induced liver injury at therapeutic doses of acetaminophen.