Browsing by Author "Koh, Christopher"

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    Abnormal liver tests are not sufficient for diagnosis of hepatic graft‐versus‐host disease in critically ill patients
    (Wolters Kluwer, 2022) Yang, Alexander H.; Han, Mai Ai Thanda; Samala, Niharika; Rizvi, Bisharah S.; Marchalik, Rachel; Etzion, Ohad; Wright, Elizabeth C.; Patel, Ruchi; Khan, Vinshi; Kapuria, Devika; Venkat, Vikramaditya Samala; Kleiner, David E.; Koh, Christopher; Kanakry, Jennifer A.; Kanakry, Christopher G.; Pavletic, Steven; Williams, Kirsten M.; Heller, Theo; Medicine, School of Medicine
    Hepatic graft-versus-host disease (HGVHD) contributes significantly to morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Clinical findings and liver biomarkers are neither sensitive nor specific. The relationship between clinical and histologic diagnoses of HGVHD was assessed premortem and at autopsy. Medical records from patients who underwent HSCT at the National Institutes of Health (NIH) Clinical Center between 2000 and 2012 and expired with autopsy were reviewed, and laboratory tests within 45 days of death were divided into 15-day periods. Clinical diagnosis of HGVHD was based on Keystone Criteria or NIH Consensus Criteria, histologic diagnosis based on bile duct injury without significant inflammation, and exclusion of other potential etiologies. We included 37 patients, 17 of whom had a cholestatic pattern of liver injury and two had a mixed pattern. Fifteen were clinically diagnosed with HGVHD, two showed HGVHD on autopsy, and 13 had histologic evidence of other processes but no HGVHD. Biopsy or clinical diagnosis of GVHD of other organs during life did not correlate with HGVHD on autopsy. The diagnostic accuracy of the current criteria was poor (κ = -0.20). A logistic regression model accounting for dynamic changes included peak bilirubin 15 days before death, and an increase from period -30 (days 30 to 16 before death) to period -15 (15 days before death) showed an area under the receiver operating characteristic curve of 0.77. Infection was the immediate cause of death in 68% of patients. In conclusion, liver biomarkers at baseline and GVHD elsewhere are poor predictors of HGVHD on autopsy, and current clinical diagnostic criteria have unsatisfactory performance. Peak bilirubin and cholestatic injury predicted HGVHD on autopsy. A predictive model was developed accounting for changes over time. Further validation is needed.
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    Associations of CDH1 germline variant location and cancer phenotype in families with hereditary diffuse gastric cancer (HDGC)
    (BMJ, 2019-06) Lo, Winifred; Zhu, Bin; Sabesan, Arvind; Wu, Ho-Hsiang; Powers, Astin; Sorber, Rebecca A.; Ravichandran, Sarangan; Chen, Ina; McDuffie, Lucas A.; Quadri, Humair S.; Beane, Joal D.; Calzone, Kathleen; Miettinen, Markku M.; Hewitt, Stephen M.; Koh, Christopher; Heller, Theo; Wacholder, Sholom; Rudloff, Udo; Surgery, School of Medicine
    INTRODUCTION: Hereditary diffuse gastric cancer (HDGC) is a cancer syndrome associated with variants in E-cadherin (CDH1), diffuse gastric cancer and lobular breast cancer. There is considerable heterogeneity in its clinical manifestations. This study aimed to determine associations between CDH1 germline variant status and clinical phenotypes of HDGC. METHODS: One hundred and fifty-two HDGC families, including six previously unreported families, were identified. CDH1 gene-specific guidelines released by the Clinical Genome Resource (ClinGen) CDH1 Variant Curation Expert Panel were applied for pathogenicity classification of truncating, missense and splice site CDH1 germline variants. We evaluated ORs between location of truncating variants of CDH1 and incidence of colorectal cancer, breast cancer and cancer at young age (gastric cancer at <40 or breast cancer <50 years of age). RESULTS: Frequency of truncating germline CDH1 variants varied across functional domains of the E-cadherin receptor gene and was highest in linker (0.05785 counts/base pair; p=0.0111) and PRE regions (0.10000; p=0.0059). Families with truncating CDH1 germline variants located in the PRE-PRO region were six times more likely to have family members affected by colorectal cancer (OR 6.20, 95% CI 1.79 to 21.48; p=0.004) compared with germline variants in other regions. Variants in the intracellular E-cadherin region were protective for cancer at young age (OR 0.2, 95% CI 0.06 to 0.64; p=0.0071) and in the linker regions for breast cancer (OR 0.35, 95% CI 0.12 to 0.99; p=0.0493). Different CDH1 genotypes were associated with different intracellular signalling activation levels including different p-ERK, p-mTOR and β-catenin levels in early submucosal T1a lesions of HDGC families with different CDH1 variants. CONCLUSION: Type and location of CDH1 germline variants may help to identify families at increased risk for concomitant cancers that might benefit from individualised surveillance and intervention strategies.
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    Characterization of Hepatic Dysfunction in subjects diagnosed with Chronic GVHD by NIH Consensus Criteria
    (Elsevier, 2022) Yang, Alexander H.; Han, Ma Ai Thanda; Samala, Niharika; Rizvi, Bisharah S.; Marchalik, Rachel; Etzion, Ohad; Wright, Elizabeth C.; Cao, Liang; Hakim, Frances T.; Jones, Elizabeth; Kapuria, Devika; Hickstein, Dennis D.; Fowler, Daniel; Kanakry, Jennifer A.; Kanakry, Christopher G.; Kleiner, David E.; Koh, Christopher; Pavletic, Steven Z.; Heller, Theo; Medicine, School of Medicine
    Hepatic chronic graft-versus-host disease (cGVHD) causes morbidity and current diagnostic criteria are nonspecific. An accurate diagnosis is imperative because overdiagnosis can lead to unnecessary treatment with immunosuppressive agents and raising the risk of opportunistic infections. We aim to characterize different patterns of liver injury and cytokine profiles associated with hepatic dysfunction in cGVHD, to evaluate the accuracy of the NIH Consensus Criteria (NCC) for hepatic cGVHD and to explore predictors for hepatic cGHVD. Patients were evaluated in this prospective cross-sectional study of patients with cGVHD recruited under a natural history protocol. Laboratory tests and cytokines were measured. The cGVHD were diagnosed and scored based on NCC. Clinically indicated liver biopsy specimens or autopsies were reviewed by an expert hepatopathologist (D.E.K.). Comparisons were made between groups, and univariable and multivariable logistic regression were calculated. Of the 302 patients enrolled, 151 fulfilled hepatic cGVHD based on NCC; however, 69% had at least 1 abnormal liver test result. Abnormal alanine aminotransferase (ALT) and aspartate aminotransferase were associated with lower platelets, higher total bilirubin (TB), total cholesterol, serum amyloid A, and IL 15. Abnormal ALP and gamma-glutamyl transpeptidase were associated with higher cholesterol, and IL7. Lower platelet count was associated with higher ALT, TB, and triglycerides and lower albumin. Of the 27 with liver tissue, 16 had histologic features of GVHD, only eight met clinical criteria for hepatic GVHD. Sensitivity and specificity of NCC in identifying hepatic GVHD were 50% and 27% (Kappa = -0.23). Only 6 had only hepatic GVHD, whereas 10 had hepatic GVHD with either iron overload, nodular regenerative hyperplasia, or steatosis. Multivariable logistic regression showed that ALP and total cholesterol were associated with hepatic GVHD and total cholesterol >220 mg/dL increased the sensitivity for histologic hepatic GVHD. In conclusion, abnormal liver enzymes in cGVHD are nonspecific and have poor correlation with histologic evidence for hepatic GVHD, highlighting the importance of histology. Cytokines provide insight into the pathogenesis of hepatic cGVHD. Decreased platelet count was associated with factors associated with liver disease including portal vein diameter, which may suggest progression of liver disease. This highlights the need of incorporating these factors in natural history study and using liver biopsy to understand the development of liver dysfunction in hematopoietic stem cell transplantation and to develop better instruments to decreased hepatic cGVHD related morbidity and mortality.
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    Garcinia cambogia, Either Alone or in Combination With Green Tea, Causes Moderate to Severe Liver Injury
    (Elsevier, 2021) Vuppalanchi, Raj; Bonkovsky, Herbert L.; Ahmad, Jawad; Barnhart, Huiman; Durazo, Francisco; Fontana, Robert J.; Gu, Jiezhun; Khan, Ikhlas; Kleiner, David E.; Koh, Christopher; Rockey, Don C.; Phillips, Elizabeth J.; Li, Yi-Ju; Serrano, Jose; Stolz, Andrew; Tillmann, Hans L.; Seeff, Leonard B.; Hoofnagle, Jay H.; Navarro, Victor J.; Medicine, School of Medicine
    Background & Aims Garcinia cambogia, either alone or with green tea, is commonly promoted for weight loss. Sporadic cases of liver failure from G cambogia have been reported, but its role in liver injury is controversial. Methods Among 1418 patients enrolled in the Drug-Induced Liver Injury Network (DILIN) from 2004 to 2018, we identified 22 cases (adjudicated with high confidence) of liver injury from G cambogia either alone (n = 5) or in combination with green tea (n = 16) or Ashwagandha (n = 1). Control groups consisted of 57 patients with liver injury from herbal and dietary supplements (HDS) containing green tea without G cambogia and 103 patients from other HDS. Results Patients who took G cambogia were between 17 and 54 years, with liver injury arising 13–223 days (median = 51) after the start. One patient died, one required liver transplantation, and 91% were hospitalized. The liver injury was hepatocellular with jaundice. Although the peak values of aminotransferases were significantly higher (2001 ± 1386 U/L) in G cambogia group (P < .018), the median time for improvement in total bilirubin was significantly lower compared with the control groups (10 vs 17 and 13 days; P = .03). The presence of HLA-B∗35:01 allele was significantly higher in the G cambogia containing HDS (55%) compared with patients because of other HDS (19%) (P = .002) and those with acute liver injury from conventional drugs (12%) (P = 2.55 × 10–6). Conclusions The liver injury caused by G cambogia and green tea is clinically indistinguishable. The possible association with HLA-B∗35:01 allele suggests an immune-mediated mechanism of injury. Clinical Trials.gov number: NCT00345930.
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    HLA-B*35:01 and Green Tea Induced Liver Injury
    (Wiley, 2021-06) Hoofnagle, Jay H.; Bonkovsky, Herbert L.; Phillips, Elizabeth J.; Li, Yi-Ju; Ahmad, Jawad; Barnhart, Huiman; Durazo, Francisco; Fontana, Robert J.; Gu, Jiezhun; Khan, Ikhlas; Kleiner, David E.; Koh, Christopher; Rockey, Don C.; Seeff, Leonard B.; Serrano, Jose; Stolz, Andrew; Tillmann, Hans L.; Vuppalanchi, Raj; Navarro, Victor J.; Medicine, School of Medicine
    Background and aims: Herbal supplements, and particularly multi-ingredient products, have become increasingly common causes of acute liver injury. Green tea is a frequent component in implicated products, but its role in liver injury is controversial. The aim of this study was to better characterize the clinical features, outcomes, and pathogenesis of green tea-associated liver injury. Approach and results: Among 1,414 patients enrolled in the U.S. Drug-Induced Liver Injury Network who underwent formal causality assessment, 40 cases (3%) were attributed to green tea, 202 to dietary supplements without green tea, and 1,142 to conventional drugs. The clinical features of green tea cases and representation of human leukocyte antigen (HLA) class I and II alleles in cases and control were analyzed in detail. Patients with green tea-associated liver injury ranged in age from 17 to 69 years (median = 40) and developed symptoms 15-448 days (median = 72) after starting the implicated agent. The liver injury was typically hepatocellular (95%) with marked serum aminotransferase elevations and only modest increases in alkaline phosphatase. Most patients were jaundiced (83%) and symptomatic (88%). The course was judged as severe in 14 patients (35%), necessitating liver transplantation in 3 (8%), but rarely resulting in chronic injury (3%). In three instances, injury recurred upon re-exposure to green tea with similar clinical features, but shorter time to onset. HLA typing revealed a high prevalence of HLA-B*35:01, found in 72% (95% confidence interval [CI], 58-87) of green tea cases, but only 15% (95% CI, 10-20) caused by other supplements and 12% (95% CI, 10-14) attributed to drugs, the latter rate being similar to population controls (11%; 95% CI, 10.5-11.5). Conclusions: Green tea-related liver injury has distinctive clinical features and close association with HLA-B*35:01, suggesting that it is idiosyncratic and immune mediated.