Hyponatremia Associated with Hepatocellular Carcinoma

Hyponatremia is the most common electrolyte abnormality in clinical practice, and a differential diagnosis of the etiologic disorders is crucial because hyponatremia is associated with many different disease states including malignancies. Although only a few cases of hyponatremia with hepatocellular carcinoma (HCC) have been previously reported, the abnormal expression of arginine vasopressin (AVP) in tumor cells has not been demonstrated. We herein present a rare case of hyponatremia associated with the aberrant expression of AVP in tumor cells of HCC. This case suggests that an extensive diagnostic work-up is needed in patients with hyponatremia because hyponatremia may provide diagnostic clues for the presence of other underlying disorders.

Angiotensin-(1-7) Attenuates Kidney Injury Due to Obstructive Nephropathy in Rats

Background

Angiotensin-(1–7) [Ang-(1–7)] counteracts many actions of the renin-angiotensin-aldosterone system. Despite its renoprotective effects, extensive controversy exists regarding the role of Ang-(1–7) in obstructive nephropathy, which is characterized by renal tubulointerstitial fibrosis and apoptosis.

Methods

To examine the effects of Ang-(1–7) in unilateral ureteral obstruction (UUO), male Sprague-Dawley rats were divided into three groups: control, UUO, and Ang-(1–7)-treated UUO rats. Ang-(1–7) was continuously infused (24 μg/[kg·h]) using osmotic pumps. We also treated NRK-52E cells in vitro with Ang II (1 μM) in the presence or absence of Ang-(1–7) (1 μM), Mas receptor antagonist A779 (1 μM), and Mas receptor siRNA (50 nM) to examine the effects of Ang-(1–7) treatment on Ang II-stimulated renal injury via Mas receptor.

Results

Angiotensin II (Ang II) and angiotensin type 1 receptor (AT₁R) protein expression was higher in UUO kidneys than in controls. Ang-(1–7) treatment also decreased proapoptotic protein expression in UUO kidneys. Ang-(1–7) also significantly ameliorated TUNEL positive cells in UUO kidneys. Additionally, Ang-(1–7) reduced profibrotic protein expression and decreased the increased tumor growth factor (TGF)-β1/Smad signaling present in UUO kidneys. In NRK-52E cells, Ang II induced the expression of TGF-β1/Smad signaling effectors and proapoptotic and fibrotic proteins, as well as cell cycle arrest, which were attenuated by Ang-(1–7) pretreatment. However, treatment with A779 and Mas receptor siRNA enhanced Ang II-induced apoptosis and fibrosis. Moreover, Ang II increased tumor necrosis factor-α converting enzyme (TACE) and decreased angiotensin-converting enzyme 2 (ACE2) expression in NRK-52E cells, while pretreatment with Ang-(1–7) or A779 significantly inhibited or enhanced these effects, respectively.

Conclusion

Ang-(1–7) prevents obstructive nephropathy by suppressing renal apoptosis and fibrosis, possibly by regulating TGF-β1/Smad signaling and cell cycle arrest via suppression of AT₁R expression. In addition, Ang-(1–7) increased and decreased ACE2 and TACE expression, respectively, which could potentially mediate a positive feedback mechanism via the Mas receptor.

Severe septicemia, necrotizing fasciitis, and peritonitis due to Vibrio vulnificus in a patient undergoing continuous ambulatory peritoneal dialysis: a case report

Background

Chronic kidney disease, including end-stage renal disease, has been identified as a possible risk factor for primary septicemia and wound infection by Vibrio vulnificus. However, cases of severe septicemia, necrotizing fasciitis, and peritonitis caused by V. vulnificus in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) have not been described. We report a case of severe septicemia, necrotizing fasciitis, and peritonitis due to V. vulnificus in a patient undergoing CAPD after ingesting raw seafood.

Case presentation

A 37-year-old woman undergoing CAPD was admitted to the emergency room due to general weakness, fever, diarrhea, and abdominal pain. Although empirical intraperitoneal antibiotics were administered for the diagnosis of CAPD-related peritonitis, her fever did not subside. On hospital day 3, she had hemorrhagic bullae on both lower legs. We evaluated her recent food history, and found that she ate raw seafood before admission. She underwent emergency fasciotomy on the suspicion of necrotizing fasciitis by V. vulnificus infection. Finally, V. vulnificus was confirmed by 16S ribosomal ribonucleic acid gene sequencing using blood and peritoneal effluent fluid cultures. The administration of intraperitoneal ceftazidime and intravenous ciprofloxacin/ceftriaxone was continued for 4 weeks, and the patient completely recovered.

Conclusions

Suspicion of V. vulnificus infection in vulnerable patients who ingest raw seafood is essential for prompt diagnosis, which could significantly improve patient outcomes.

Association of serum adiponectin level with albuminuria in chronic kidney disease patients

BACKGROUND

Adiponectin, a peptide hormone secreted from adipocytes, exerts anti-diabetic, anti-atherogenic, and anti-inflammatory properties. We aimed to determine the relationship between serum adiponectin levels and albuminuria, and evaluate determinant factors for serum adiponectin in patients with chronic kidney disease (CKD).

METHODS

In total, 1442 CKD patients were included and divided into three groups according to their albumin-to-creatinine ratios: patients with normoalbuminuria (N = 228), microalbuminuria (N = 444), and macroalbuminuria (N = 761). Serum adiponectin was specifically assayed with a commercially available enzyme-linked immunosorbent assay kit.

RESULTS

Serum adiponectin was significantly higher in patients with macroalbuminuria than in those without macroalbuminuria (9.7 ± 6.0, 12.4 ± 9.0, and 14.9 ± 11.0 μg/mL in patients with normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively). Univariate linear regression analysis showed that the serum adiponectin concentrations were correlated with age, the albumin-to-creatinine ratio, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, whereas they were negatively correlated with body mass index, the estimated glomerular filtration rate, and serum albumin and triglyceride levels. The stepwise regression multiple analysis showed that sex; the estimated glomerular filtration rate; body mass index; total cholesterol, high-density lipoprotein cholesterol, and triglyceride levels; and logarithm of the albumin-to-creatinine ratio were independently associated with the logarithm of serum adiponectin levels (r = 0.55, p < 0.001).

CONCLUSION

Serum adiponectin concentrations are higher in patients with increasing albuminuria, and these levels are associated with renal insufficiency and lipid profiles.

Risk factors for in-hospital mortality in patients starting hemodialysis

BACKGROUND

Incident hemodialysis patients have the highest mortality in the first several months after starting dialysis. This study evaluated the in-hospital mortality rate after hemodialysis initiation, as well as related risk factors.

METHODS

We examined in-hospital mortality and related factors in 2,692 patients starting incident hemodialysis. The study population included patients with acute kidney injury, acute exacerbation of chronic kidney disease, and chronic kidney disease. To determine the parameters associated with in-hospital mortality, patients who died in hospital (nonsurvivors) were compared with those who survived (survivors). Risk factors for in-hospital mortality were determined using logistic regression analysis.

RESULTS

Among all patients, 451 (16.8%) died during hospitalization. The highest risk factor for in-hospital mortality was cardiopulmonary resuscitation, followed by pneumonia, arrhythmia, hematologic malignancy, and acute kidney injury after bleeding. Albumin was not a risk factor for in-hospital mortality, whereas C-reactive protein was a risk factor. The use of vancomycin, inotropes, and a ventilator was associated with mortality, whereas elective hemodialysis with chronic kidney disease and statin use were associated with survival. The use of continuous renal replacement therapy was not associated with in-hospital mortality.

CONCLUSION

Incident hemodialysis patients had high in-hospital mortality. Cardiopulmonary resuscitation, infections such as pneumonia, and the use of inotropes and a ventilator was strong risk factors for in-hospital mortality. However, elective hemodialysis for chronic kidney disease was associated with survival.

Prognostic impact of hyponatraemia in patients with colorectal cancer

AIM

Hyponatraemia is a common in surgical practice, but its clinical impact in patients with colorectal cancer has not been evaluated.

METHOD

We retrospectively assessed 2944 patients who had been admitted to Chonnam National University Hwasun Hospital, Korea with a diagnosis of colorectal cancer. In order to determine the relationship between the serum sodium level and 3-year mortality, we categorized the patients as having normonatraemia (135-147 mEq/l), or mild (130-134 mEq/l), moderate (125-129 mEq/l) or severe hyponatraemia (< 125 mEq/l).

RESULTS

Hyponatraemia, defined as a serum sodium level of < 135 mEq/l, was evident in 27.6% of patients during hospitalization. Declining serum sodium levels were associated with increasing age, a higher number of comorbidities, a more advanced TNM stage and worsening biochemical parameters. In a multivariate Cox-proportional regression analysis, the mortality risk was correlated with the severity of hyponatraemia [hazard ratio (HR) 1.65, 95% CI 1.38-1.96; HR 2.24, 95% CI 1.69-2.98; HR 2.20, 95% CI 1.25-3.90, for patients with mild, moderate, and severe hyponatraemia, respectively, compared with patients with normonatraemia]. An independent association between hyponatraemia and long-term mortality was sustained among various subpopulations and patients with persistent hyponatraemia had a worse prognosis than those with hyponatraemia that resolved.

CONCLUSION

A substantial proportion of patients developed hyponatraemia during hospitalization, and the long-term mortality risk increased even in mild cases of hyponatraemia. Hyponatraemia should be considered as an important prognostic factor in colorectal cancer.

Decreased Renal Expression of H(+)-ATPase and Pendrin in a Patient with Distal Renal Tubular Acidosis Associated with Sjögren's Syndrome

A 31-year-old woman with no significant past medical or family history was admitted with complaints of general weakness. Laboratory tests revealed: serum potassium 3.0 mEq/L, arterial blood pH 7.28, serum bicarbonate 17.8 mEq/L and urinary pH 7.0. Double-labeling confocal fluorescence microscopy using H(+)-ATPase and pendrin antibodies demonstrated a decreased expression of these proteins in the patient's renal collecting duct compared to normal controls. Anti-Sjögren's-syndrome-related antigen A (Anti-Ro/SS-A) and anti-Sjögren's syndrome type B (anti-La/SS-B) antibodies were strongly positive with very high titers, consistent with Sjögren's syndrome. We present a case of distal renal tubular acidosis-associated Sjögren's syndrome with a defect in H(+)-ATPase and pendrin in the renal collecting duct.

Impact of partial nephrectomy on kidney function in patients with renal cell carcinoma

BACKGROUND

This study aimed to compare the changes in kidney function and the association of tumor size and renal outcomes between patients with renal cell carcinoma (RCC) who underwent radical nephrectomy (RN) and those who underwent partial nephrectomy (PN).

METHODS

A retrospective cohort study was conducted for 557 patients with an RCC of ≤7 cm in diameter and normal contralateral kidney function who underwent PN or RN. PN was performed for 218 (39%) patients. Renal outcomes included the incidence of acute kidney injury (AKI), new-onset chronic kidney disease (CKD), and a ≥25% decline in eGFR 1 year after surgery.

RESULTS

Serial changes in eGFR were compared during the 3 years of follow-up. Postoperative eGFR was significantly lower in patients undergoing RN than in those undergoing PN. The incidence of AKI and new-onset CKD was significantly higher in patients after RN (70.1% vs. 24.3%, respectively; P<0.001) than after PN (55.7% vs. 6.2%, respectively; P<0.001). According to the multivariable logistic regression analysis, RN was an independent risk factor for a ≥25% decline in kidney function after 1 year regardless of the tumor size, even after adjusting for various covariates.

CONCLUSIONS

Compared to PN, RN for even a moderate sized RCC leads to an increased incidence of AKI and new-onset CKD, and is a significant risk factor for kidney function decline. Therefore, PN should be considered as the choice of surgical treatment for RCCs that are ≤7 cm in diameter in order to preserve renal function postoperatively.

Acute interstitial nephritis induced by Dioscorea quinqueloba

BACKGROUND

The use of herbal medicine may be a risk factor for the development of kidney injury, as it has been reported to cause various renal syndromes. Dioscorea quinqueloba is a medicinal herb that is used as an alternative therapy for cardiovascular disease and various medical conditions.

CASE PRESENTATION

A 52-year-old man was admitted with complaints of skin rash and burning sensation. He had ingested a raw extract of D. quinqueloba as a traditional remedy. Laboratory tests revealed the following values: absolute eosinophil count, 900/mm(3); serum creatinine level, 2.7 mg/dL; and blood urea nitrogen, 33.0 mg/dL. The immunoglobulin E level was markedly increased at 1320.0 IU/mL. Urinalysis revealed a fractional excretion of sodium of 3.77%, protein 1+, and blood 3+. Histological examination of the renal biopsy specimen showed a diffusely edematous interstitium with infiltrates composed of eosinophils, lymphocytes, and neutrophils.

CONCLUSION

Here, we present the first reported case of biopsy-proven acute interstitial nephritis following ingestion of D. quinqueloba associated with skin rash, eosinophilia, and increased plasma immunoglobulin E level.

Does gender influence the impact of impaired renal function on prognosis after ST-segment elevated myocardial infarction?

BACKGROUND

A limited number of studies have investigated the impact of gender on renal function and clinical outcomes after ST-segment elevated myocardial infarction (STEMI), and these studies have provided discrepant results.

METHODS AND RESULTS

This study was based on a retrospective cohort, the Korean Acute Myocardial Infarction Registry (KAMIR). Patients (n = 7,679) with a discharge diagnosis of STEMI were analyzed to investigate association of gender with renal function and clinical outcomes. Compared to men, women were older and exhibited more comorbidity, including impaired renal function. Women showed higher mortality compared to men (1-month mortality,5.6% in men vs. 12.6% in women, p < 0.001; 1-year mortality, 6.8% in men vs. 14.4% in women, p < 0.001). The risk of death proportionally increased as estimated glomerular filtration rate (eGFR) decreased in both genders. After adjusting for potential confounders, hazard ratios for women did not significantly differ from those for men at each eGFR level.The interaction test showed no significant interaction between gender and eGFR in 1-month mortality and 1-year mortality.

CONCLUSIONS

Impaired renal function was an independent prognostic factor after STEMI in both genders, and the impact of impaired renal function on prognosis after STEMI did not significantly differ between genders.

Activation of G-protein-coupled receptor 40 attenuates the cisplatin-induced apoptosis of human renal proximal tubule epithelial cells

G-protein-coupled receptor 40 (GPR40) is known to play a role in the regulation of fatty acids, insulin secretion and inflammation. However, the pathophysiological roles of GPR40 in kidney disease have not yet been identified. In the present study, we investigated the expression of GPR40 during cisplatin-induced kidney injury using male Sprague-Dawley rats that were treated with 8 mg/kg cisplatin. Control rats were treated with saline. Following treatment with cisplatin, the protein expression of GPR40 in the kidneys was decreased in association with an increase in serum creatinine levels and the Bax/Bcl-2 expression ratio. To further investigate the function of GPR40, the human renal proximal tubule epithelial cell line (HK-2) was cultured with cisplatin in the absence or presence of GW9508, a selective GPR40 agonist. Pre-treatment of the HK-2 cells with GW9508 attenuated the decrease in cell viability induced by treatment with cisplatin. Treatment with cisplatin increased the number of cells with condensed nuclei, which was ameliorated by GW9508 pre-treatment. TUNEL assay also revealed that pre-treatment with GW9508 ameliorated cisplatin-induced apoptosis. Treatment with cisplatin increased the Bax/Bcl-2 expression ratio and cleaved caspase-3 expression, and promoted the activation of nuclear factor-κB (NF-κB). These changes were attenuated by pre-treatment with GW9508. The cisplatin-induced generation of reactive oxygen species (ROS) and the activation of the Src/epidermal growth factor receptor (EGFR)/extracellular signal-regulated kinase (ERK) pathway were also counteracted by pre-treatment with GW9508. Thus, the activation of GPR40 attenuates cisplatin-induced apoptosis by inhibiting the generation of ROS, the activation of the Src/EGFR/ERK signaling pathway and the nuclear activation of NF-κB and pro-apoptotic factors.

Metabolic syndrome and chronic kidney disease in an adult Korean population: results from the Korean National Health Screening

Background

This study was aimed to examine the prevalence of metabolic syndrome (MS) and chronic kidney disease (CKD), and the association between MS and its components with CKD in Korea.

Methods

We excluded diabetes to appreciate the real impact of MS and performed a cross-sectional study using the general health screening data of 10,253,085 (48.86±13.83 years, men 56.18%) participants (age, ≥20 years) from the Korean National Health Screening 2011. CKD was defined as dipstick proteinuria ≥1 or an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m².

Results

The prevalence of CKD was 6.15% (men, 5.37%; women, 7.15%). Further, 22.25% study population had MS (abdominal obesity, 27.98%; hypertriglyceridemia, 30.09%; low high-density cholesterol levels, 19.74%; high blood pressure, 43.45%; and high fasting glucose levels, 30.44%). Multivariate-adjusted analysis indicated that proteinuria risk increased in participants with MS (odds ratio [OR] 1.884, 95% confidence interval [CI] 1.867–1.902, P<0.001). The presence of MS was associated with eGFR<60 mL/min/1.73 m² (OR 1.364, 95% CI 1.355–1.373, P<0.001). MS individual components were also associated with an increased CKD risk. The strength of association between MS and the development of CKD increase as the number of components increased from 1 to 5. In sub-analysis by men and women, MS and its each components were a significant determinant for CKD.

Conclusions

MS and its individual components can predict the risk of prevalent CKD for men and women.

Relation of serum potassium level to long-term outcomes in patients with acute myocardial infarction

Potassium plays a key role in normal myocardial function, and current guidelines recommend that serum potassium levels be maintained from 4.0 to 5.0 mEq/L in patients with acute myocardial infarction (AMI). However, the impact of serum potassium levels on long-term mortality has not been evaluated. We retrospectively studied 1,924 patients diagnosed with AMI. The average serum potassium levels measured throughout the hospitalization were obtained and statistically analyzed. Patients were categorized into 5 groups to determine the relation between mean serum potassium and long-term mortality: <3.5, 3.5 to <4.0, 4.0 to <4.5, 4.5 to <5.0, and ≥5 mEq/L. The long-term mortality was lowest in the group of patients with potassium levels of 3.5 to <4.0 mEq/L, whereas mortality was higher in the patients with potassium levels≥4.5 or <3.5 mEq/L. In a multivariate Cox-proportional regression analysis, the mortality risk was greater for serum potassium levels of >4.5 mEq/L (hazard ratio [HR] 1.71, 95% confidence interval [CI] 1.04 to 2.81 and HR 4.78, 95% CI 2.14 to 10.69, for patients with potassium levels of 4.5 to <5.0 mEq/L and ≥5.0, respectively) compared with patients with potassium levels of 3.5 to <4.0 mEq/L. The mortality risk was also higher for patients with potassium levels<3.5 mEq/L (HR 1.55, 95% CI 0.94 to 2.56). In contrast to the association with long-term mortality, there was no relation between serum potassium levels and the occurrence of ventricular arrhythmias. The results of the current analysis suggest that there is a need for change in our current concepts of the ideal serum potassium levels in patients with AMI.

Association of age and BP variability with long-term mortality in hemodialysis patients

BACKGROUND/AIMS

Blood pressure (BP) variability is known as a poor prognostic factor for cardiovascular outcomes. This study assessed the prognostic significance of BP variability in association with increasing age in hemodialysis patients.

METHODS

We retrospectively analyzed 2,174 patients on hemodialysis from March 2005 to December 2012. The impact of intradialytic and interdialytic BP variability on all-cause mortality according to age groups was analyzed.

RESULTS

Kaplan-Meier survival curves for 5-year cumulative mortality showed higher mortality in patients with higher intradialytic systolic and diastolic BP variability as well as interdialytic systolic and diastolic BP variability (log-rank p=0.006, <0.001, 0.018 and < 0.001) in patients aged <55 years, but not in older age groups. Cox proportional analysis revealed that 5-year mortality was associated with intradialytic diastolic BP variability in patients aged <55 years (HR, 2.03 CI, 1.24-3.32).

CONCLUSION

The overall mortality was associated with BP variability in patients aged <55 years, but not in older ages. This result suggests that younger hemodialysis patients with BP variability require further medical attention and intervention to reduce BP variability.

Alpha-lipoic acid attenuates lipopolysaccharide-induced kidney injury

BACKGROUND

Kidney is one of the major target organs in sepsis, while effective prevention of septic acute kidney injury has not yet been established. α-Lipoic acid (LA) has been known to exert beneficial effects against lipopolysaccharide (LPS)-induced damages in various organs such as heart, lung, and liver. We investigated the protective effect of LA on LPS-induced kidney injury.

METHODS

Two groups of rats were treated with LPS (20 mg/kg, i.p.), one of which being co-treated with LA (50 mg/kg), while the control group was treated with vehicle alone. Human renal proximal tubular epithelial cells (HK-2 cells) were cultured with or without LPS (10 μg/ml) in the presence or absence of LA (100 μg/ml) for 3 h prior to LPS treatment.

RESULTS

Serum creatinine level was increased in LPS-treated rats, which was attenuated by LA co-treatment. LPS treatment induced cleaved caspase-3 expression in the kidney, which was counteracted by LA. Terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive cells increased in the kidneys of LPS-treated rats compared with controls, which was counteracted by LA treatment. Protein expression of inducible nitric oxide synthase and cyclooxygenase-2 detected by immunoblotting and/or immunohistochemical staining, along with mRNA levels of pro-inflammatory cytokines detected by real-time polymerase chain reaction, was increased in the kidney with LPS administration, which was ameliorated with LA treatment. LA also protected LPS-induced tubular dysfunction, preserving type 3 Na(+)/H(+) exchanger and aquaporin 2 expressions in the kidney. Suppression of LPS-induced expression of cleaved caspase-3 by LA was also observed in HK-2 cells. Increased protein expression of phospho-extracellular signal-regulated kinases 1/2 and c-Jun N-terminal kinases by LPS treatment was attenuated by LA pretreatment, while p38 was not affected by either LPS or LA treatment. MitoTracker Red demonstrated LA prevented LPS-induced increment of mitochondrial oxidative stress, where concurrent 4',6-diamidino-2-phenylindole staining also revealed marked fragmentation and condensation of nuclei in HK-2 cells treated with LPS, which was prevented by LA.

CONCLUSION

LA treatment attenuates LPS-induced kidney injury, such as renal tubular dysfunction, by suppression of apoptosis, and inflammation.