The double-barrel wet colostomy: An alternative for urinary diversion after pelvic exenteration.

AIM: Pelvic exenteration is a radical procedure used to treat locally advanced and/or recurrent pelvic malignancies. Different reconstruction options exist, the most popular being the end colostomy with ileal conduit. The double barrel wet colostomy (DBWC) offers concomitant fecal and urinary diversion through a single stoma, but is infrequently utilized. We aim to review the evidence base of the postoperative complications, long-term oncologic risks and quality of life following creation of a double barrel wet colostomy. METHODS: A narrative review of the literature was performed evaluating the DBWC. Patient demographics, perioperative complications, operative variables, long terms oncologic outcomes and quality of life data were extracted. Descriptive statistics were used to define the data. RESULTS: Fourteen articles with a total of 300 patients undergoing DBWC following pelvic exenteration were selected. 41% of malignancies were gastrointestinal in origin while 41.7% were gynecologic and 5.3% genitourinary. 42% of patients experienced at least one complication within in 40 days of surgery, the most common being wound infection (8.7%) and urinary leak (8.3%). There was no evidence of malignancy within the DBWC during long-term surveillance. Quality of life following DBWC is comparable to other reconstructive methods. CONCLUSION: The DBWC is a well described reconstructive method for urinary and fecal diversion utilizing a single stoma following pelvic exenteration. The short- and long-term outcomes following DBWC are comparable to other reconstructive methods and the quality of life with a DBWC is acceptable. DBWC should remain a readily available option for reconstruction following pelvic exenteration.

Coordinated nuclear receptor regulation of the efflux transporter, Mrp2, and the phase-II metabolizing enzyme, GSTpi, at the blood-brain barrier.

Xenobiotic efflux pumps at the blood-brain barrier are critical modulators of central nervous system pharmacotherapy. We previously found expression of the ligand-activated nuclear receptor, pregnane X receptor (PXR), in rat brain capillaries, and showed increased expression and transport activity of the drug efflux transporter, P-glycoprotein, in capillaries exposed to PXR ligands (pregnenolone-16alpha-carbonitrile (PCN) and dexamethasone) in vitro and in vivo. Here, we show increased protein expression and transport activity of another efflux pump, multidrug resistance-associated protein isoform 2 (Mrp2), in rat brain capillaries after in vitro and in vivo exposure to PCN and dexamethasone. The phase-II drug-metabolizing enzyme, glutathione S-transferase-pi (GSTpi), was found to be expressed in brain capillaries, where it colocalized to a large extent with Mrp2 at the endothelial cell luminal plasma membrane. Like Mrp2, GSTpi protein expression increased with PXR activation. Colocalization and coordinated upregulation suggest functional coupling of the metabolizing enzyme and efflux transporter. These findings indicate that, as in hepatocytes, brain capillaries possess a regulatory network consisting of nuclear receptors, metabolizing enzymes, and efflux transporters, which modulate blood-brain barrier function.