Acid-Mediated Kidney Injury Across the Spectrum of Metabolic Acidosis.

Metabolic acidosis affects about 15% of patients with chronic kidney disease. As kidney function declines, the kidneys progressively fail to eliminate acid, primarily reflected by a decrease in ammonium and titratable acid excretion. Several studies have shown that the net acid load remains unchanged in patients with reduced kidney function; the ensuing acid accumulation can precede overt metabolic acidosis, and thus, indicators of urinary acid or potential base excretion, such as ammonium and citrate, may serve as early signals of impending metabolic acidosis. Acid retention, with or without overt metabolic acidosis, initiates compensatory responses that can promote tubulointerstitial fibrosis via intrarenal complement activation and upregulation of endothelin-1, angiotensin II, and aldosterone pathways. The net effect is a cycle between acid accumulation and kidney injury. Results from small- to medium-sized interventional trials suggest that interrupting this cycle through base administration can prevent further kidney injury. While these findings inform current clinical practice guidelines, large-scale clinical trials are still necessary to prove that base therapy can limit chronic kidney disease progression or associated adverse events.

Clinical efficacy of gastric per-oral endoscopic myotomy (G-POEM) in the treatment of refractory gastroparesis and predictors of outcomes: a systematic review and meta-analysis using surgical pyloroplasty as a comparator group.

BACKGROUND AND AIMS: Gastric peroral endoscopic myotomy (G-POEM) is a novel minimally invasive technique in endosurgery. Data is limited as to its efficacy, safety, and predictive factors. We conducted this meta-analysis to evaluate the clinical outcomes of G-POEM and used the outcomes of surgical pyloroplasty as a comparator group in the treatment of refractory gastroparesis. METHODS: We searched multiple databases from inception through March 2019 to identify studies that reported on G-POEM and pyloroplasty in gastroparesis. Our primary outcome was to analyze and compare the pooled rates of clinical success, in terms of Gastroparesis Cardinal Symptom Index (GCSI) score and 4-h gastric emptying study (GES) results, with G-POEM and pyloroplasty. RESULTS: Three hundred and thirty-two and 375 patients underwent G-POEM (11 studies) and surgical pyloroplasty (seven studies), respectively. The pooled rate of clinical success, based on the GCSI score, with G-POEM was 75.8% (95% CI 68.1-82.1, I2 = 50) and with surgical pyloroplasty was 77.3% (95% CI 66.4-85.4, I2 = 0), with no significance, p = 0.81. The pooled rate of clinical success, based on the 4-hour GES results, with G-POEM was 85.1% (95% CI 68.9-93.7, I2 = 74) and with surgical pyloroplasty was 84% (95% CI 64.4-93.8, I2 = 81), with no significance, p = 0.91. The overall adverse events were comparable. Based on meta-regression analysis, idiopathic gastroparesis, prior treatment with botulinum toxin and gastric stimulator seemed to predict clinical success with G-POEM. CONCLUSION: G-POEM demonstrates clinical success in treating refractory gastroparesis. Idiopathic gastroparesis, prior treatment with botulinum injections and gastric stimulator appear to have positive predictive effects on the 4-h GES results after G-POEM. Outcomes seem comparable to surgical pyloroplasty.