Publications

Most lung transplantation immunosuppression regimens include tacrolimus. Single nucleotide polymorphisms (SNPs) in genes important to tacrolimus bioavailability and clearance (ABCB1, CYP3A4, and CYP3A5) are associated with differences in tacrolimus pharmacokinetics. We hypothesized that polymorphisms in these genes would impact immunosuppression-related outcomes. We categorized ABCB1, CYP3A4, and CYP3A5 SNPs for 321 lung allograft recipients. Genotype effects on time to therapeutic tacrolimus level, interactions with antifungal medications, concentration to dose (C /D), acute kidney injury, and rejection were assessed using linear models adjusted for subject characteristics and repeat measures. Compared with CYP3A poor metabolizers (PM), time to therapeutic tacrolimus trough was increased by 5.1 ± 1.6 days for CYP3A extensive metabolizers (EM, P < 0.001). In the post-operative period, CYP3A intermediate metabolizers spent 1.2 ± 0.5 days less (P = 0.01) and EM spent 2.1 ± 0.5 days less (P < 0.001) in goal tacrolimus range than CYP3A PM. Azole antifungals interacted with CYP3A genotype in predicting C /D (P < 0.001). Increased acute kidney injury rates were observed in subjects with high ABCB1 function (OR 3.0, 95% CI 1.1-8.6, P = 0.01). Lower rates of acute cellular rejection were observed in subjects with low ABCB1 function (OR 0.36, 95% CI 0.07-0.94, P = 0.02). Recipient genotyping may help inform tacrolimus dosing decisions and risk of adverse clinical outcomes.

Acute severe lower gastrointestinal bleeding (LGIB) can be treated by endoscopy safely and effectively. At present, the data on the efficacy of endoscopy in the treatment of patients with LGIB are still being collected. Thus, guidelines to manage patients with LGIB are still in development. Herein, based on the recent literature and their twenty year experience in their units in the US and in Japan, the authors summarize the role of endoscopic hemostasis therapy in acute severe LGIB with a focus on how to perform the hemostasis techniques.

Lower gastrointestinal bleeding is bleeding from a colonic source. Rapid colon purge using 4 to 6 L of polyethylene glycol followed by early colonoscopy, within 24 hours of presentation, is recommended to optimize the detection and management of bleeding sources. Although the data are mixed, early colonoscopy seems to be associated with higher detection of bleeding lesions and therapeutic interventions. There is no clear benefit for early colonoscopy in terms of reduced duration of stay, rebleeding, transfusion requirement, or surgery compared with patients undergoing elective colonoscopy. Further studies are needed to determine the effect of early colonoscopy on clinically important outcomes.