IntroductionLittle is known of the clinical outcomes of secondary oxalate nephropathy. To inform clinical practice, we performed a systematic review of case reports and case series to examine the clinical characteristics and outcomes of patients with secondary oxalate nephropathy.MethodsElectronic databases were searched for case reports and case series of individual cases or cohorts of patients with biopsy-proven oxalate nephropathy in native or transplanted kidneys from 1950 until January 2018.ResultsFifty-seven case reports and 10 case series met the inclusion criteria, totaling 108 patients. The case series were meta-analyzed. Mean age was 56.4 years old, 59% were men, and 15% were kidney transplant recipients. Fat malabsorption (88%) was the most commonly attributed cause of oxalate nephropathy, followed by excessive dietary oxalate consumption (20%). The mean baseline serum creatinine was 1.3 mg/dl and peaked at 4.6 mg/dl. Proteinuria, hematuria, and urinary crystals was reported in 69%, 32%, and 26% of patients, respectively. Mean 24-hour urinary oxalate excretion was 85.4 mg/d. In addition to universal oxalate crystal deposition in tubules and/or interstitium, kidney biopsy findings included acute tubular injury (71%), tubular damage and atrophy (69%), and interstitial mononuclear cell infiltration (72%); 55% of patients required dialysis. None had complete recovery, 42% had partial recovery, and 58% remained dialysis-dependent. Thirty-three percent of patients died.ConclusionSecondary oxalate nephropathy is a rare but potentially devastating condition. Renal replacement therapy is required in >50% of patients, and most patients remain dialysis-dependent. Studies are needed for effective preventive and treatment strategies in high-risk patients with hyperoxaluria-enabling conditions.

Background Urinary liver-type fatty acid-binding protein (L-FABP) is a proximal tubular injury candidate biomarker for early detection of acute kidney injury (AKI), with variable performance characteristics depending on clinical settings. Study Design Meta-analysis of diagnostic test studies assessing the performance of urinary L-FABP in AKI. Setting & Population Literature search in MEDLINE, EMBASE, Scopus, Google Scholar, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov using search terms “liver-type fatty acid-binding protein” and “L-FABP”. Selection Criteria for Studies Human studies investigating the performance characteristics of urinary L-FABP for early diagnosis of AKI and AKI-related outcomes, including dialysis requirement and mortality. Predictor Urinary L-FABP. Outcomes Diagnosis of AKI, dialysis requirement, and in-hospital death. Results 15 prospective cohort studies and 2 case-control studies were identified. Only 7 cohort studies could be meta-analyzed. The estimated sensitivity of urinary L-FABP for diagnosis of AKI was 74.5% (95% CI, 60.4-84.8), and the specificity was 77.6% (95% CI, 61.5-88.2). The estimated sensitivity of urinary L-FABP for predicting dialysis requirement was 69.1% (95% CI, 34.6-90.5), and the specificity was 42.7% (95% CI, 3.1-94.5); for in-hospital mortality, sensitivity and specific were 93.2% (95% CI, 66.2-99.0) and 78.8% (95% CI, 27.0-97.4), respectively. Limitations Paucity and low quality of studies, different clinical settings, and variable definitions of AKI. Conclusions Although urinary L-FABP may be a promising biomarker for early diagnosis of AKI, and for predicting dialysis requirement and in-hospital mortality, its potential value needs to be validated in large studies and across a broader spectrum of clinical settings.

Although convective therapies are associated with improved clearance of uremic solutes, the potential long-term benefits of specific convective modalities require further study.

Background: Evidences suggest that chronic systemic inflammation is associated with increasing mortality in maintenance hemodialysis patients due to atherosclerosis and malnutrition. Periodontal diseases are treatable sources of systemic inflammation in hemodialysis patients. We therefore evaluated the effect of periodontal treatment in maintenance hemodialysis patients. Method: Periodontal diseases were evaluated in 30 stable maintenance hemodialysis patients by using clinical periodontal status by plaque index (PI) and periodontal disease index (PDI). Hematologic, biochemical, nutritional, and dialysis-related parameters as well as highly sensitive C-reactive protein (hs-CRP), a sensitive systemic inflammatory marker, were analyzed before and after periodontal therapy. Result: Maintenance hemodialysis patients had high prevalence of periodontal disease (63%). At baseline, hs-CRP positively correlated with clinical periodontal status (PI, r = 0.74, p < 0.001; PDI, r = 0.66, p < 0.001), but negatively correlated with hemoglobin (r = −0.51, p < 0.001), serum albumin (r = −0.61, p = 0.002), and normalized protein catabolic rate (r = −0.42, p = 0.043). After completion of periodontal therapy (duration 6 ± 2 weeks), the PI and PDI significantly declined from 2.13 to 1.48 (p = 0.001) and 3.53 to 2.52 (p = 0.001), respectively, while hs-CRP significantly declined from 3.8 to 0.6 mg/L (p < 0.001). Moreover, erythropoietin dosage could be reduced from 8000 to 6000 unit/week (p = 0.03) after treatment. Pre-dialysis blood urea nitrogen increased from 66.18 to 79.54 mg/dL (p = 0.003) and serum albumin level increased from 3.15 to 3.38 mg/dL (p = 0.003), reflecting improved nutritional status of the patients after periodontal treatment. Conclusion: Periodontitis is an important source of chronic inflammation. Treatment of periodontal diseases can improve systemic inflammation, nutritional status, and erythropoietin responsiveness in the hemodialysis population.