Identification of flucloxacillin-modified hepatocellular proteins: implications in flucloxacillin-induced liver injury.

Flucloxacillin is a ß-lactam antibiotic associated with a high incidence of drug-induced liver injury. Although expression of HLA-B*57:01 is associated with increased susceptibility, little is known of the pathological mechanisms involved in the induction of the clinical phenotype. Irreversible protein modification is suspected to drive the reaction through the provision of flucloxacillin-modified peptides that are presented to T-cells by the protein encoded by the risk allele. In this study, we have shown that flucloxacillin binds to multiple proteins within human primary hepatocytes, including major hepatocellular proteins (hemoglobin and albumin) and mitochondrial proteins. Inhibition of membrane transporters multidrug resistance-associated protein 2 (MRP2) and P-glycoprotein (P-gp) appeared to reduce the levels of covalent binding. A diverse range of proteins with different functions was found to be targeted by flucloxacillin, including adaptor proteins (14-3-3), proteins with catalytic activities (liver carboxylesterase 1, tRNA-splicing endonuclease subunit Sen2, All-trans-retinol dehydrogenase ADH1B, Glutamate dehydrogenase 1 mitochondrial, Carbamoyl-phosphate synthase [ammonia] mitochondrial), and transporters (hemoglobin, albumin, and UTP-glucose-1-phosphate uridylyltransferase). These flucloxacillin-modified intracellular proteins could provide a potential source of neoantigens for HLA-B*57:01 presentation by hepatocytes. More importantly, covalent binding to critical cellular proteins could be the molecular initiating events that lead to flucloxacillin-induced cholestasis Data are available via ProteomeXchange with identifier PXD038581.

Surgical management of suspected gallbladder cancer: The role of intraoperative frozen section for diagnostic confirmation.

BACKGROUND: Preoperative diagnosis for suspected gallbladder cancers is challenging, with a risk of overtreating benign disease, for example, xanthogranulomatous cholecystitis, with radical cholecystectomies. We retrospectively evaluated the surgeon's intraoperative assessment alone, and with the addition of intraoperative frozen sections, for suspected gallbladder cancers from a tertiary hepatobiliary multidisciplinary team (MDT). METHODS: MDT patients with complex gallbladder disease were included. Collated data included demographics, MDT discussion, operative details, and patient outcomes. RESULTS: A total of 454 patients with complex gallbladder disease were reviewed, 48 (10.6%) were offered radical surgery for suspected cancer. Twenty-five underwent frozen section that led to radical surgery in 6 (25%). All frozen sections were congruent with final histopathology but doubled the operating time (p < 0.0001). Both the surgeon's subjective and additional frozen section's objective assessment, allowed for de-escalation of unnecessary radical surgery, comparing favourably to a 13.0% cancer diagnosis among radical surgery historically. CONCLUSIONS: The MDT process was highly sensitive in identifying gallbladder cancers but lacked specificity. The surgeon's intraoperative assessment is paramount in suspected cancers, and deescalated unnecessary radical surgery. Intraoperative frozen section was a safe and viable adjunct at a cost of resources and operative time.

A cohort study analysing outcomes following transanal haemorrhoidal dearterialisation (THD).

BACKGROUND: Although conventional open haemorrhoidectomy and stapled haemorrhoidectomy are effective procedures, they can lead to significant post-operative pain with risks to continence. Current evidence favours transanal haemorrhoidal dearterialisation (THD) and targeted mucopexy to be an efficacious alternative to conventional modalities. Our aim was to assess the midterm outcomes following THD. METHODS: Prospective data was collected for patients undergoing day case THD under a single consultant over a 9-year period (March 2009 to February 2018). Data collected included: intra-operative findings, post-operative pain (defined as requirement of analgesia in recovery), post-operative complications and requirement of further procedures. RESULTS: Over this time period, 271 patients underwent THD, with 203 (74.9%) patients also undergoing targeted mucopexy for 2nd to 4th degree haemorrhoids. Only 4 (1.5%) patients suffered from post-operative complications, including significant bleeding (n = 1), urinary retention (n = 1) and constipation (n = 2). Post-operative pain was identified in only 10 (3.7%) patients; eight of which had simultaneously undergone an additional procedure (e.g. excision of anal polyps and skin tags). Only 5 (1.8%) patients were identified that required further haemorrhoidal invasive intervention subsequently. CONCLUSIONS: These results are comparable with national data and demonstrate that THD is a safe procedure for symptomatic haemorrhoids with minimal morbidity.

Prognostic and predictive markers in liver limited stage IV colorectal cancer.

Colorectal cancer is the third most commonly diagnosed cancer among both men and women. Personalised treatment options remain complex, although there is broad agreement over which patients with colorectal liver metastases (CRLM) should and should not be offered resection. Decisions on an optimal management strategy involves careful assessment of both technical and oncological factors. In this review we aim to summarise current prognostic biomarkers for metastatic colorectal cancers, specifically patients considered for resection. A number of clinico-pathological factors have been identified as prognostically important with good internal validity, but limited external validity. Furthermore, these prognostic scoring systems do not take factor in modern chemotherapeutic agents and the disease modification these agents produce. Histopathological response to chemotherapy is of significant prognostic importance. Molecular markers can help predict the efficacy of a biological agent. An important prognostic factor of liver metastasis is the recognition that location of the primary colorectal cancer impacts on metastatic phenotype and represents difference in genotype, i.e. proximal tumours are more aggressive than distal tumours with an increased likelihood of disease progression. Several mutational molecular markers identified include microsatellite instability, BRAF, and KRAS/NRAS and combination mutations, which confer poorer outcomes. Accurate prognostication in patients with liver limited colorectal metastases remains crucial, as this allows tailoring treatment options to each disease and improving outcomes. Access to tissue before treatment remains a limitation although advances in ability to assess tumour biology by non-invasive methods are promising.

Validation of clinical prognostic scores for patients treated with curative-intent for recurrent colorectal liver metastases.

BACKGROUND: Scoring systems were developed to stratify patients with colorectal liver metastases considered for liver resection into different risk groups. Such scores have never been evaluated in recurrent liver metastases. The aim of this study was to evaluate whether these scores are applicable to patients with recurrent colorectal liver metastases and treated with curative intent. METHODS: We retrospectively analyzed data from 375 consecutive patients who underwent liver surgery for colorectal liver metastases between June 2010 and August 2015. Seventy-three patients developed liver-limited recurrence treated with curative intent. The predictive value of 6 scores (Fong, Sofocleous, Nagashima, Nordlinger, Konopke, and the Basingstoke index) was assessed in this set of patients. RESULTS: Median follow-up was 36.2 months. Overall survival and progression-free survival were 33.6 and 5.6 months, respectively. When scores were applied for OS, none showed a significant stratification between patients, although Nagashima's score showed a significant difference in overall survival between patients from the low-risk group and those from the intermediate- and high-risk groups (40.8 vs 30.5 months, P = 0.039). For PFS, only Fong's score showed a statistically significant stratification (6.6 vs 4.7 months, P = 0.027). CONCLUSION: Scoring systems are of limited-value in stratifying patients operated on for recurrent colorectal liver metastases.