The effect of probiotic supplementation on systemic inflammation in dialysis patients

Emerging evidence suggests that intestinal dysbiosis contributes to systemic inflammation and cardiovascular diseases in dialysis patients. The purpose of this study was to evaluate the effects of probiotic supplementation on various inflammatory parameters in hemodialysis (HD) patients. Methods: Twenty-two patients with maintenance HD were enrolled. These patients were treated twice a day with 2.0 ×1010 colony forming units of a combination of Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI for 3 months. The microbiome and fecal short-chain fatty acids (SCFAs) were analyzed. The percentages of CD14+ CD16+ proinflammatory monocytes and CD4+ CD25+ regulatory T-cells (Tregs) before and after probiotic supplementation were determined by flow cytometry. Serum levels of calprotectin and cytokine responses upon lipopolysaccharide (LPS) challenge were compared before and after probiotic supplementation. Results: Fecal SCFAs increased significantly after probiotic supplementation. Serum levels of calprotectin and interleukin 6 upon LPS stimulation significantly decreased. The anti-inflammatory effects of probiotics were associated with a significant increase in the percentage of CD4+ CD25+ Tregs (3.5% vs. 8.6%, p < 0.05) and also with a decrease of CD14+ CD16+ proinflammatory monocytes (310/ mm2 vs. 194/mm2 , p < 0.05). Conclusion: Probiotic supplementation reduced systemic inflammatory responses in HD patients and this effect was associated with an increase in Tregs and a decrease in proinflammatory monocytes. Hence, targeting intestinal dysbiosis might be a novel strategy for decreasing inflammation and cardiovascular risks in HD patients.

The effect of periodontitis on recipient outcomes after kidney transplantation

Recent several reports have demonstrated that periodontitis is prevalent and adversely affects the survival in patients with chronic kidney disease (CKD) or end-stage kidney disease. However, its impact on transplant outcomes remains uncertain. Methods: This retrospective cohort study included 136 and 167 patients, respectively, who underwent living donor kidney transplantation (KT) at Seoul National University Hospital from July 2012 to August 2016 and Korea University Hospital from April 2008 to October 2018. We divided patients into three groups according to stages of periodontitis based on a new classification system. Results: Patients with severe periodontitis were older, had a higher prevalence of diabetes, a higher body mass index and C-reactive protein level, a lower cardiac output, and were more likely to be smokers, indicating its association with chronic systemic inflammation. After KT, stage IV periodontitis was independently associated with a lower incidence of acute T cell-mediated rejection, suggesting the possible effect of periodontitis on immune function. However, 1-year and 3-year estimated glomerular filtration rates were not different. Among the KT recipients followed up more than 3 years, new-onset cardiovascular disease occurred in nine patients, and coronary artery disease occurred more frequently in patients with stage IV periodontitis. However, diabetes was the independent predictor of new-onset coronary artery disease in multivariate logistic regression analysis. Conclusion: Our findings showed that periodontitis might be an important player in determining posttransplant outcomes in recipients. Further interventional trials to test whether treating periodontitis could modify transplant outcome are needed.

A Case Report of Thrombotic Thrombocytopenia After ChAdOx1 nCov-19 Vaccination and Heparin Use During Hemodialysis

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but life-threatening complication. VITT strongly mimics heparin-induced thrombocytopenia (HIT) and shares clinical features. Heparin is commonly used to prevent coagulation during hemodialysis.Therefore, nephrologists might encounter patients needing dialysis with a history of heparin exposure who developed thrombotic thrombocytopenia after vaccination. A 70-year-old male presented with acute kidney injury and altered mental status due to lithium intoxication. He needed consecutive hemodialysis using heparin. Deep vein thrombosis of left lower extremity and accompanying severe thrombocytopenia of 15,000/µL on 24 days after vaccination and at the same time, nine days after heparin use. Anti-platelet factor 4 antibody test was positive.Anticoagulation with apixaban and intravenous immunoglobulin (IVIG) infusion resolved swelling of his left calf and thrombocytopenia. There were no definitive diagnostic tools capable of differentiating between VITT and HIT in this patient. Although VITT and HIT share treatment with IVIG and non-heparin anticoagulation, distinguishing between VITT and HIT will make it possible to establish a follow-up vaccination plan in a person who has had a thrombocytopenic thrombotic event. Further research is needed to develop the tools to make a clear distinction between the clinical syndromes.

Probiotics partially attenuate the severity of acute kidney injury through an immunomodulatory effect

Background@#A healthy microbiome helps maintain the gut barrier and mucosal immune tolerance. Previously, we demonstrated that acute kidney injury (AKI) provoked dysbiosis, gut inflammation, and increased permeability. Here, we investigated the renoprotective effects of the probiotic Bifidobacterium bifidum BGN4 and the underlying mechanisms thereof. @*Methods@#C57BL/6 mice were subjected to bilateral renal ischemia-reperfusion injury (IRI) or sham operation. In the probiotic-treated group, BGN4 was administered by gavage once daily, starting 2 weeks before injury. @*Results@#Administration of BGN4 significantly increased gut microbiome diversity and prevented expansion of the Enterobacteriaceae and Bacteroidetes that were the hallmarks of AKI-induced dysbiosis. Further, BGN4 administration also significantly reduced other IRI-induced changes in the colon microenvironment, including effects on permeability, apoptosis of colon epithelial cells, and neutrophil and proinflammatory macrophage infiltration. Mononuclear cells co-cultured with BGN4 expressed significantly increased proportions of CD103+/CD11c+ and CD4+ CD25+ Treg cells, suggesting a direct immunomodulatory effect. BGN4 induced Treg expansion in colon, mesenteric lymph nodes (MNL), and kidney. BGN4 also reduced CX3CR1intermediateLy6Chigh monocyte infiltration and interleukin (IL)-17A suppression in the small intestine, which may have attenuated AKI severity, kidney IL-6 messenger RNA expression, and AKI-induced liver injury. @*Conclusion@#Prior supplementation with BGN4 significantly attenuated the severity of IRI and secondary liver injury. This renoprotective effect was associated with increased Foxp3 and reduced IL-17A expression in the colon, MNL, and kidney, suggesting that BGN4-induced immunomodulation might contribute to its renoprotective effects. Probiotics may therefore be a promising strategy to reduce AKI severity and/or remote organ injury.

Pathogens of peritoneal dialysis peritonitis: Trends from a single-center experience over 15 years

Background@#Concerns are increasing about the emergence of pathogens with antibiotic resistance in peritoneal dialysis (PD) peritonitis. We investigated the current pathogen trends and risk factors in PD peritonitis. @*Methods@#We conducted a retrospective study analyzing data from 643 patients who maintained PD over 3 months between January 2001 and December 2015. The isolated pathogens from PD peritonitis were compared between period A (2001-2008) and period B (2009-2015). @*Results@#Among 643 PD patients, 252 patients experienced one or more episodes of PD peritonitis (total 308 episodes) during the median follow-up of 66 months. In both periods, gram-positive bacteria were the dominant pathogens (22.2% vs. 53.8%, P < 0.01). Gram-negative bacteria showed an increasing tendency in period B, but without statistical significance (17.0% vs. 23.7%, P = 0.15). The culture-negative rate was improved from 57% in period A to 18% in period B (P < 0.01). There was no increase in the prevalence of resistant pathogens such as methicillin-resistant Staphylococcus epidermidis (MRSE), Staphylococcus aureus (MRSA) and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli between periods A and B. Preserved residual renal function was associated with a lower risk of PD peritonitis (odds ratio, 0.53; 95% confidence interval, 0.31-0.88; P = 0.01). @*Conclusion@#Over the past two decades, the pathogens of PD peritonitis have not significantly changed in Korea. Gram-positive organisms remained dominant, with S. epidermidis being the most common pathogen. Resistant bacteria such as MRSE, MRSA, ESBL-producing Gram-negative bacilli did not increase, but should be monitored.

Urinary tissue inhibitor of metalloproteinase-2 and insulin-like growth factor-binding protein 7 as biomarkers of patients with established acute kidney injury

Background/Aims@#Urinary tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been recently discovered and validated as sensitive biomarkers that can predict stage 2 or 3 acute kidney injury (AKI) development in high-risk patients. We aimed to assess whether these biomarkers could predict adverse outcomes and renal recovery in established AKI patients. @*Methods@#This was a single-center study prospectively enrolling 124 patients diagnosed with AKI. TIMP-2, IGFBP7, neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule 1 (KIM-1) levels were measured at the time of diagnosis and the predictive performance of short-term outcomes and renal recovery was assessed. @*Results@#Patients were divided into 4 quartiles according to the initial urinary TIMP-2/IGFBP7 levels. Stage 3 AKI (odds ratio [OR], 17.86), classified by the Kidney Disease Improving Global Outcomes (KDIGO), as well as the third and fourth quartiles of TIMP-2/IGFBP7 (OR, 5.75 and 44.98, respectively), were found to be independent predictors of renal replacement therapy at the time of AKI diagnosis. In addition, KDIGO stage 3 AKI (OR, 2.468) or the third of fourth quartiles of urinary TIMP-2/IGFBP7 (OR, 1.896 and 3.622, respectively) were also found to be useful in predicting nonrecovery of renal function. In a separate analysis of patients with renal recovery at discharge, initial urinary TIMP-2/IGFBP7 or urinary IGFBP7 at discharge could also predict new-onset or progressive chronic kidney disease (CKD). @*Conclusions@#In AKI patients, urine TIMP-2/IGFBP7 could serve as a biomarker for predicting adverse outcomes, renal recovery, or the development and progression of CKD.

Long-term Renal Outcome of Biopsy-proven Acute Tubular Necrosis and Acute Interstitial Nephritis

Background@#Although emerging evidence suggest acute kidney injury (AKI) progress to chronic kidney disease (CKD), long-term renal outcome of AKI still remains unclear. Acute tubular necrosis (ATN) is the most common cause of AKI due to ischemia, toxin or sepsis. Acute interstitial nephritis (AIN), caused by drugs or autoimmune diseases is also increasingly recognized as an important cause of AKI. Unlike glomerular diseases, AKI is usually diagnosed in the clinical context without kidney biopsies, and lack of histology might contribute to this uncertainty. @*Methods@#Among 8,769 biopsy series, 253 adults who were histologically diagnosed with ATN and AIN from 1982 to 2018 at five university hospitals were included. Demographic and pathological features that are associated with the development of end stage renal disease (ESRD) were also examined. @*Results@#Rate of non-recovery of renal function at 6 month was significantly higher in the AIN (ATN vs AIN 49.3 vs 69.4%, P = 0.007) with a 2.71-fold higher risk of non- recovery compared to ATN (95% confidence interval [CI], 1.20–6.47). During the mean follow up of 76.5 ± 91.9 months, ESRD developed in 39.4% of patients with AIN, and 21.5% patients of ATN. The risk of ESRD was significantly higher in AIN (23.05; 95% CI, 2.42–219.53) and also in ATN (12.14; 95% CI, 1.19–24.24) compared to control with non-specific pathology. Older age, female gender, renal function at the time of biopsy and at 6 months, proteinuria and pathological features including interstitial inflammation and fibrosis, tubulitis, vascular lesion were significantly associated with progression to ESRD. @*Conclusion@#Our study demonstrated that patients with biopsy proven ATN and AIN are at high risk of developing ESRD. AIN showed higher rate of non-renal recovery at 6 month than ATN.

Diastolic dysfunction and acute kidney injury in elderly patients with femoral neck fracture

BACKGROUND: Femoral neck fracture is common in the elderly population. Acute kidney injury (AKI) is an important risk factor for mortality in patients who have had such fracture. We evaluated the incidence of AKI in patients who had femoral neck fracture and identified risk factors for AKI and mortality. METHODS: This was an observational cohort study including 285 patients who were ≥ 65 years of age and who underwent femoral neck fracture surgery between 2013 and 2017. RESULTS: The mean age was 78.63 ± 6.75 years. A total of 67 (23.5%) patients developed AKI during the hospital stay: 57 (85.1%), 5 (7.5%), and 5 (7.5%) patients were classified as having stage 1, 2, and 3 AKI, respectively. Patients with AKI had a lower baseline estimated glomerular filtration rate and higher left atrial dimension, left ventricular mass index, pulmonary artery pressure, and the ratio of early mitral inflow velocity to early diastolic mitral annulus velocity (E/e’) and were more likely to have diabetes or hypertension (HTN) (P < 0.05). The presence of HTN (odds ratio [OR], 4.570; 95% confidence interval [CI], 1.632–12.797) higher E/e’ (OR, 1.105; 95% CI, 1.019–1.198), and lower hemoglobin (OR, 0.704; 95% CI, 0.528–0.938) were independently associated with a higher risk for developing AKI. Severe AKI (OR, 24.743; 95% CI, 2.822–212.401) was associated with a higher risk of mortality. CONCLUSION: Elderly patients with femoral neck fracture had a high incidence of AKI. Diastolic dysfunction was associated with AKI. Severe AKI was associated with in-hospital mortality.

Retroperitoneal fibrosis in the era of immunoglobulin G4-related disease

BACKGROUND: Retroperitoneal fibrosis (RPF) is a rare disease characterized by fibroinflammatory tissue in the periaortic or periiliac retroperitoneum, where it frequently encases ureters. There is emerging evidence that a subset of this disease is part of a spectrum of multisystemic autoimmune diseases collectively referred to as “immunoglobulin G4 (IgG4)-related disease”. METHODS: We retrospectively analyzed 27 idiopathic RPF patients and identified a subset as IgG4-related RPF, which we categorized according to recently published comprehensive diagnostic criteria. We compared clinical and laboratory characteristics and response to treatment between the two groups. RESULTS: Of 27 total patients, 16 (59.3%) were diagnosed as having IgG4-related RPF, and these were predominantly male. They were also significantly older and more likely to have other organ involvement, hydronephrosis, and postrenal acute kidney injury (AKI) compared to those with idiopathic RPF. However, there was no difference in response rate to systemic steroid treatment. CONCLUSION: IgG4-related RPF accounts for a substantial portion of RPF cases previously identified as “idiopathic RPF” in Korea. Clinical and laboratory characteristics of IgG4-related RPF are similar to those of idiopathic RPF except for a striking male predominance, older age, and higher incidence of postrenal AKI in IgG4-related RPF. More comprehensive, prospective studies are needed to clearly distinguish IgG4-related RPF from idiopathic RPF based on clinical manifestation and to further assess treatment response and long-term prognosis.

Blocking junctional adhesion molecule C promotes the recovery of cisplatin-induced acute kidney injury

BACKGROUND/AIMS: Recent findings have demonstrated the occurrence of neutrophil transendothelial migration in the reverse direction (reverse TEM) and that endothelial junctional adhesion molecule C (JAM-C) is a negative regulator of reverse TEM. In this study, we tested the effects of a JAM-C blocking antibody on the resolution of kidney injuries and inflammation in a mouse model of cisplatin-induced acute kidney injury (AKI). METHODS: Cisplatin was administered via intraperitoneal injection. A JAM-C blocking antibody or a control immunoglobulin G was administered intraperitoneal at 1.5 mg/kg, with the injection being delayed until day 4 following cisplatin administration to restrict the effect of antibodies on recovery. RESULTS: After cisplatin injection, serum creatinine and histologic injuries peaked on day 4. Treatment with a JAM-C blocking antibody on days 4 and 5 promoted the functional and histologic recovery of cisplatin-induced AKI on days 5 and 6. Facilitating recovery with a JAM-C blocking antibody correlated with significantly increased circulating intercellular adhesion molecule 1+ Tamm-Horsfall protein+ neutrophils and significantly decreased renal neutrophil infiltration, indicating that facilitating reverse the TEM of neutrophils from the kidney to the peripheral circulation partially mediated the resolution of inflammation and recovery. CONCLUSIONS: These results demonstrated that reverse TEM is involved in the resolution of neutrophilic inflammation in cisplatin-induced AKI and that JAM-C is an important regulator of this process.

Advanced chronic kidney disease: a strong risk factor for Clostridium difficile infection

BACKGROUND/AIMS: It has been suggested that chronic kidney disease (CKD) is a risk factor for Clostridium difficile infection (CDI) and is associated with increased mortality among patients infected with C. difficile. However, recent studies of the clinical impact of CKD on CDI in Asians are still insufficient. We sought to determine the relationship between CKD and CDI in a Korean population. METHODS: This was a single-center, retrospective case-control study. In total, 171 patients with CDI were included as cases and 342 age- and gender-matched patients without CDI were used as controls. We compared the prevalence of CKD in the study sample and identified independent risk factors that could predict the development or prognosis of CDI. RESULTS: Independent risk factors for CDI included stage IV to V CKD not requiring dialysis (odds ratio [OR], 2.90) and end-stage renal disease requiring dialysis (OR, 3.34). Patients with more advanced CKD (estimated glomerular filtration rate < 30) and CDI showed higher in-hospital mortality and poorer responses to the initial metronidazole therapy. CONCLUSIONS: More advanced CKD is an independent risk factor for CDI and is associated with higher in-hospital mortality and poor treatment responses in CDI patients. Thus, in CKD patients, careful attention should be paid to the occurrence of CDI and its management to improve the outcome of CDI.

Predictive factors of acute kidney injury in patients undergoing rectal surgery

BACKGROUND: Despite major advance in surgical techniques from open surgery to robot-assisted surgery, acute kidney injury (AKI) is still major postoperative complication in rectal surgery. The purpose of this study is to compare the incidence of postoperative AKI according to different surgical techniques and also the risk factors, outcomes of AKI in patients undergoing rectal cancer surgery. METHODS: A retrospective medical chart review was done in a total of 288 patients who received proctectomy because of rectal cancer from 2011 to 2013. RESULTS: The mean patient age was 62 ± 12 years, and male was 64.2%. Preoperative creatinine was 0.91 ± 0.18 mg/dL. Open surgery was performed in 9%, and laparoscopy assisted surgery or robot assisted surgery were performed in 54.8% or 36.1% of patients, respectively. AKI developed in 11 patients (3.82%), 2 (18%) of them received acute hemodialysis. Incidence of AKI was not different according to the surgical technique, however, the presence of diabetes, intraoperative shock, and postoperative ileus was associated with the development of AKI. In addition, AKI patients showed significantly longer hospital stay and higher mortality than non-AKI patients. CONCLUSION: Our study demonstrated that despite advances in surgical techniques, incidence of postoperative AKI remains unchanged and also that postoperative AKI is associated with poor outcome. We also found that presence of diabetes, intraoperative shock and postoperative ileus are strongly associated with the development of AKI. More careful attention should be paid on high risk patients for the development of postoperative AKI regardless of surgical techniques.

Etiology and outcomes of anuria in acute kidney injury: a single center study

BACKGROUND: It was previously known that anuric acute kidney injury (AKI) is uncommon and its occurrence suggests complete ureteral obstruction, shock, or a major vascular event. As the epidemiology of AKI has significantly changed over the past decade, it is possible that the incidence, etiology, or clinical characteristics of anuric AKI have also changed. METHODS: A prospective cohort study was conducted that included all patients undergoing renal replacement therapy (RRT) for AKI during a 2-year period in a tertiary hospital. Patients were classified as having anuric, oliguric, or nonoliguric AKI based on their volume of urine when RRT started using the modified Acute Kidney Injury Network criteria. RESULTS: Of the 203 patients included in the study, 21.2% met the criteria for anuric AKI. Septic and postoperative AKI were the main causes of anuric AKI, with 60.5% of incidences occurring in hospital. Anuric AKI was associated with a younger age, a lower prevalence of pre-morbid chronic kidney disease and diabetes, more frequent continuous RRT requirement, and multi-organ dysfunction. In addition, patients with anuric AKI had a higher rate of in-hospital mortality and long-term dependence on RRT than patients with nonanuric AKI. CONCLUSION: Anuric AKI is common, with sepsis as the main etiological insult, and is associated with adverse outcomes among patients with AKI who require RRT.

Relationship between pulmonary hypertension, peripheral vascular calcification, and major cardiovascular events in dialysis patients

BACKGROUND: Pulmonary hypertension (PHT) is a recently recognized complication of chronic kidney disease. In this study, we investigated the association between PHT, peripheral vascular calcifications (VCs), and major cardiovascular events. METHODS: In this retrospective study, we included 172 end-stage renal disease (ESRD) patients undergoing dialysis [hemodialysis (HD)=84, peritoneal dialysis=88]. PHT was defined as an estimated pulmonary artery systolic pressure >37 mmHg using echocardiography. The Simple Vascular Calcification Score (SVCS) was measured using plain radiographic films of the hands and pelvis. RESULTS: The prevalence of PHT was significantly higher in HD patients (51.2% vs. 22.7%). Dialysis patients with PHT had a significantly higher prevalence of severe VCs (SVCS> or =3). In multivariate analysis, the presence of severe VCs [odds ratio (OR), 2.68], mitral valve disease (OR, 7.79), HD (OR, 3.35), and larger left atrial diameter (OR, 11.39) were independent risk factors for PHT. In addition to the presence of anemia, severe VCs, or older age, the presence of PHT was an independent predictor of major cardiovascular events in ESRD patients. CONCLUSION: The prevalence of PHT was higher in HD patients and was associated with higher rates of major cardiovascular events. Severe VCs are thought to be an independent risk factor for predicting PHT in ESRD patients. Therefore, in dialysis patients with PHT, careful attention should be paid to the presence of VCs and the occurrence of major cardiovascular events.

Intra-abdominal hypertension does not predict renal recovery or in-hospital mortality in critically ill patients with acute kidney injury

BACKGROUND: Although emerging evidence suggests that intra-abdominal hypertension (IAH) is a predictor of the development of acute kidney injury (AKI), it remains unclear whether the presence of IAH is a predictor of prognosis in patients with AKI. The purpose of this study was to assess whether the presence of IAH could predict prognosis in critically ill patients with AKI. The prognostic value of urinary biomarkers was also determined. METHODS: In this prospective observational study, we enrolled 57 patients with established AKI, who were admitted to the intensive care unit between February 2012 and June 2014. IAH was defined as a sustained elevation in intra-abdominal pressure of > or =12 mmHg, in three consecutive measurements performed daily on the first 3 days. Urinary neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid-binding protein, and simplified acute physiology score II score at the time of admission were also examined. RESULTS: IAH was observed in 78.9% of patients. The in-hospital mortality was 21.1%, and renal recovery during hospitalization was achieved in 40.4% of patients. Although high urinary NGAL [odds ratio (OR), 1.015] and liver-type fatty acid-binding protein (OR, 1.003) were found to be independent predictors of renal recovery, IAH was not. High urinary NGAL (OR, 1.003) and a high simplified acute physiology score II score (OR, 1.102) were independent predictors of in-hospital mortality, while IAH or urinary liver-type fatty acid-binding protein was not. CONCLUSION: Although IAH is prevalent in critically ill patients with AKI, it did not predict AKI prognosis. However, urinary NGAL was found to be a useful predictor of both renal recovery and in-hospital mortality.

The Role of Urinary Liver-Type Fatty Acid-Binding Protein in Critically Ill Patients

Although several urinary biomarkers have been validated as early diagnostic markers of acute kidney injury (AKI), their usefulness as outcome predictors is not well established. This study aimed to determine the diagnostic and prognostic abilities of urinary liver-type fatty acid-binding protein (L-FABP) in heterogeneous critically ill patients. We prospectively collected data on patients admitted to medical and surgical intensive care units (ICUs) from July 2010 to June 2011. Urine neutrophil gelatinase-associated lipocalin (NGAL) and L-FABP at the time of ICU admission were quantitated. Of the 145 patients, 54 (37.2%) had AKI defined by the Acute Kidney Injury Network (AKIN) criteria. AKI patients showed significantly higher level of urinary NGAL and L-FABP and also higher mortality than non-AKI patients. The diagnostic performances, assessed by the area under the ROC curve, were 0.773 for NGAL and 0.780 for L-FABP, demonstrating their usefulness in diagnosing AKI. In multivariate Cox analysis, urinary L-FABP was an independent predictor for 90-day mortality. Urinary L-FABP seems to be promising both for the diagnosis of AKI and for the prediction of prognosis in heterogeneous ICU patients. It needs to be further validated for clinical utility.

Proinflammatory CD14+CD16+ monocytes are associated with vascular stiffness in predialysis patients with chronic kidney disease

BACKGROUND: Chronic inflammation is frequently noted in patients with chronic kidney disease (CKD) and contributes to the development and progression of cardiovascular diseases. Monocytes are heterogeneous populations of cells, and they can be divided into subtypes with different phenotypes and functions based on CD14 and CD16 positivity. This study examined whether the proinflammatory CD14+CD16+ monocyte subset expands in predialysis CKD patients, and also whether the expansion of these cells is closely associated with systemic inflammation and cardiovascular risk factors. METHODS: The percentages of proinflammatory CD14+CD16+ monocytes were analyzed in 111 predialysis CKD patients using a flow cytometer, and they were compared with brachial-ankle pulse wave velocity as well as the cytokine plasma levels and other clinical parameters. RESULTS: The proportion of CD14+CD16+ monocytes was significantly higher in patients with advanced stages of CKD than in patients with the early stages. Interleukin-6 levels were also high in patients with advanced stages of CKD. The expansion of CD14+CD16+ monocytes showed significant positive correlations with the high-sensitive C-reactive protein levels, and negative correlations with the levels of serum albumin, hemoglobin, and 25(OH)-vitamin D. In addition, the expansion of CD14+CD16+ monocytes was an independent factor correlated with brachial-ankle pulse wave velocity in diabetic CKD patients. CONCLUSION: Expansion of the proinflammatory CD14+CD16+ monocyte subset partially accounts for chronic inflammation, malnutrition, and atherosclerosis in CKD

Bilateral gluteal compartment syndrome complicated by rhabdomyolysis and acute kidney injury in a patient with alcohol intoxication

Bilateral gluteal compartment syndrome is a rare clinical entity that can be complicated by rhabdomyolysis or acute kidney injury (AKI). We report the a case of a 30-year-old woman without any comorbid diseases who was diagnosed with bilateral gluteal compartment syndrome complicated by rhabdomyolysis and dialysis-requiring AKI, which was caused by prolonged immobilization under the influence of alcohol. Although the patient's renal function recovered fully after 5 sessions of hemodialysis, sciatic neuropathy caused by gluteal compartment syndrome led to permanent foot drop.

Acute Kidney Injury: Differential Diagnosis and New Biomarker / 대한내과학회지

Incidence of acute kidney injury (AKI) is increasing and despite advances in supportive care, mortality from AKI in critically ill patients still exceeds 50%. Major causes of AKI can be classified into prerenal, renal and postrenal AKI and many of prerenal or ischemic acute tubular necrosis (ATN) are caused by decreased renal blood flow. In addition, exposure to nephrotoxicant or diverse drugs can lead to AKI and diseases that affect larger renal vessels, glomeruli, or renal microvasculature are also other causes of AKI. Because type of renal injury or initiation of proper therapy in setting of AKI is important in determining patient prognosis, differential diagnosis utilizing patients history, physical examination, and laboratory data including urinalysis, urine diagnostic indices, radiologic examination is important. Lack of sensitive biomarkers for early detection of AKI, which resembles troponin in acute myocardial infarction is one critical factor that has hampered the successful translation of various therapeutic strategies that were effective in animal research. However, over the last decade, efforts to identify and validate novel urine or plasma biomarkers in AKI led to identification of several promising biomarkers including neutrophil gelatinase associated lipocalin (NGAL), interleukin-18 (IL-18), cystatin-C and liver type fatty acid binding protein (L-FABP). Although far from replacing serum creatinine in clinical practice yet, data from large clinical studies are promising and here I briefly reviewed the characteristics of them and possible clinical utility in AKI.

Carpal Tunnel Syndrome and Peripheral Polyneuropathy in Patients with End Stage Kidney Disease

This study was designed to identify the causes of the development of carpal tunnel syndrome (CTS) associated with end stage kidney disease (ESKD). A total of 112 patients with ESKD, 64 on hemodialysis (HD) and 48 on peritoneal dialysis (PD), were enrolled. The duration of ESKD and dialysis, the site of the arteriovenous (A-V) fistula for HD, laboratory data such as blood urea nitrogen, creatinine, and beta-2-microglobulin were determined. Clinical evaluation of CTS and electrophysiological studies for the diagnosis of CTS and peripheral neuropathy were performed. The electrophysiological studies showed that the frequency of CTS was not different in the HD and PD groups (P = 0.823) and the frequency of CTS was not different in the limb with the A-V fistula compared to the contralateral limb (P = 0.816). The frequency of HD and PD were not related to beta-2-microglobulin levels, an indicator of amyloidosis. The frequency of CTS did not increase as the severity of the peripheral neuropathy and the duration of ESKD and dialysis increased (P = 0.307). The results of this study do not support that microglobulin induced amyloidosis or placement of an A-V fistula are associated with an increase in CTS.