Prevalence and Clinical Characteristics of Asymptomatic Pyuria in Chronic Kidney Disease

BACKGROUND: Pyuria seems to be common in chronic kidney disease (CKD), irrespective of urinary tract infection (UTI). It has been hypothesized that sterile pyuria occurs in CKD because of chronic renal parenchymal inflammation. However, there are limited data on whether CKD increases the rate of pyuria or how pyuria in CKD should be interpreted. We investigated the prevalence and characteristics of asymptomatic pyuria (ASP) in CKD via urinary white blood cell (WBC) analysis.METHODS: Urine examination was performed for all stable hemodialysis (HD) and non-dialysis CKD patients of the outpatient clinic (total N=298). Patients with infection symptoms or recent history of antibiotic use were excluded. Urine culture and WBC analysis were performed when urinalysis revealed pyuria.RESULTS: The prevalence of ASP was 30.5% (24.1% in non-dialysis CKD and 51.4% in HD patients). Over 70% of the pyuria cases were sterile. The majority of urinary WBCs were neutrophils, even in sterile pyuria. However, the percentage of neutrophils was significantly lower in sterile pyuria. In multivariate logistic regression analysis, the degree of pyuria, percentage of neutrophils, and presence of urinary nitrites remained independently associated with sterile pyuria.CONCLUSIONS: The prevalence of ASP was higher in CKD patients and increased according to CKD stage. Most ASP in CKD was sterile. Ascertaining the number and distribution of urinary WBCs may be helpful for interpreting ASP in CKD.

Which dialysis unit blood pressure is the most accurate for predicting home blood pressure in patients undergoing hemodialysis?

BACKGROUND/AIMS: We investigated which dialysis unit blood pressure (BP) is the most useful for predicting home BP in patients undergoing hemodialysis (HD). METHODS: Patients undergoing HD who had been treated > 3 months were included in this study. Exclusion criteria were hospitalized patients with acute illness and changes in dry weight and anti-hypertensive drugs 2 weeks before the study. We used the dialysis unit BP recording data, such as pre-HD, intra-HD, post-HD, mean pre-HD, and post-HD (pre-post-HD), mean pre-HD, intra-HD, and post-HD (pre-intra-post-HD) BP. Home BP (the same period of dialysis unit BP) was monitored as a reference method during 2 weeks using the same automatic oscillometric device. Patients were asked to record their BP three times daily (wake up, between noon and 6:00 PM, and at bedtime). RESULTS: Significant differences were detected between home systolic blood pressure (SBP) and pre-HD, post-HD, and intra-HD SBP (p = 0.003, p = 0.001, p = 0.016, respectively). In contrast, no differences were observed between home SBP and pre-intra-post-HD and pre-post-HD SBP (p = 0.235, p = 0.307, respectively). Areas under the receiver operating characteristic curve for pre-intra-post-HD and prepost-HD SBP with 2-week home BP as the reference standard were 0.812 and 0.801, respectively. CONCLUSIONS: These results suggest that pre-intra-post-HD and pre-post-HD SBP had similar accuracy for predicting mean 2-week home SBP in HD patients. Therefore, pre-intra-post-HD and pre-post-HD SBP should be useful for predicting home SBP in HD patients if ambulatory or home BP measurements are unavailable.

Consumption of an Excessive Amount of Ionic Beverage Can Trigger Adrenal Adenoma - Induced Severe Hypokalemic Rhabdomyolysis / 대한내과학회지

Rhabdomyolysis results from acute damage to skeletal muscles caused by various conditions, of which hypokalemia is a recognized but rare example. Although primary aldosteronism may cause severe hypokalemia leading to rhabdomyolysis, the potassium level of such patients can be within the normal range. Hypokalemia is most frequently triggered when these patients are exposed to an additional insult, such as diuretic stress. Similarly, overzealous consumption of ionic beverages with osmotic diuretic effects can cause hypokalemia. Here, we describe a patient with an aldosterone-secreting adrenal adenoma, who presented with acute rhabdomyolysis secondary to severe hypokalemia triggered by consumption of a large volume of ionic beverage for 3 weeks.

A Case of Bilateral Renal Infarction of Unknown Cause in a Previously Healthy Young Male

We report a rare case of bilateral renal infarction resulting in acute renal failure in a previously healthy 26-year-old soldier. The patient presented with an abdominal pain and bilateral costovertebral angle tenderness. Laboratory studies showed elevated serum creatinine, mild leukocytosis, and increased lactate dehydrogenase. Contrast-enhanced computed tomography showed multiple perfusion defects in both kidneys with wedge-shaped infarction in right kidney. Kidney biopsy performed in the left kidney revealed microinfarction. Comprehensive work-up did not reveal any specific causes or risk factors except smoking, and the infarction was considered to be idiopathic. He emphasized that he received extremely strenuous military training several days before he came to the hospital. He was treated with low molecular weight heparin with significant improvement in renal function. Further studies are needed for the characterization of idiopathic renal infarction in previously healthy individuals and evaluating the mechanisms including strenuous physical activity on the renal blood flow.

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.

An age-dependent alteration of the respiratory exchange ratio in the db/db mouse / 한국실험동물학회지

The leptin receptor-deficient db/db mouse is a rodent model of type 2 diabetes and obesity. Diabetes in db/db mice shows an age-dependent progression, with early insulin resistance followed by an insulin secretory defect resulting in profound hyperglycemia. However, there is insufficient data on agedependent changes of energy metabolism in db/db mice. We demonstrated an age-dependent decrease in the respiratory exchange ratio (RER), calculated by a ratio of VO2/VCO2, in db/db mice. The RER determined by indirect calorimetry, was 1.03 in db/db mice under 6 weeks of age, which were similar to those in heterozygote (db/+) and wild-type (+/+) mice. However, RER decreased from approximately 0.9 to 0.8 by 10 weeks of age and subsequently returned to approximately 0.9 at 22 weeks of age. The changes in RER were concurrent with the alterations in body weight and blood glucose level. However, other metabolic indicators such as glucose tolerance, changes in body fat mass, and urinary glucose levels, did not change with age. The results suggested that the energy source utilized in db/db mice changed with the age-related progression of diabetes.

Clinical Characteristics and Outcomes of Septic Acute Kidney Injury in Critically Ill Patients / 대한신장학회지

PURPOSE: This study was to determine the clinical characteristics and outcomes of critically ill patients with septic acute kidney injury (AKI). METHODS: We retrospectively collected data of patients with AKI who were > or =18 years of age and admitted to the intensive care unit (ICU) for > or =24 hours from April 2007 to December 2009, and compared the clinical characteristics and outcomes of patients with and without sepsis. RESULTS: Of the 1,075 patients, 333 had AKI, as defined by the RIFLE criteria, and 134 of them had AKI with sepsis. Septic AKI had significantly higher SAPS II and SOFA scores, and required more mechanical ventilation and vasoactive drugs than non-septic AKI. Patients with septic AKI progressed more to the failure category of the RIFLE criteria. Patients with septic AKI had higher in-hospital mortality and required more RRT, compared to patients with non-septic AKI. Amongst survivors, patients with septic AKI were more likely to recover renal function. A higher SAPS II score and a greater requirement for vasoactive drugs and renal replacement therapy were independently associated with increased in-hospital mortality in septic AKI. CONCLUSION: Patients with septic AKI have a higher burden of illness with an increased risk of death, but renal function recovers better in survivors of septic AKI.

Clinical Features of Hyponatremia: Changes Related to Increasing Use of Thiazide-Combination Diuretics / 대한신장학회지

PURPOSE: In this study, the etiology and the change of clinical characteristics of hyponatremia, in relation to the increased used of thiazide diuretics, have been assessed. METHODS: To perform a retrospective cohort study, a total sum of 322 patients who have been admitted in a single tertiary referral hospital between 2004 and 2009, were included. RESULTS: The most common cause of hyponatremia was due to thiazide diuretics (37.6%). Among the 121 patients who suffered from thiazide induced hyponatremia, 60 (48.0%) patients took combination thiazide. The incidence of hyponatremia has shown a tendency to increase from 2004 to 2009 (trend test, p<0.001). The incidence of hyponatremia due to the use of combination types has also increased (trend test, p<0.001). Thiazide induced hyponatremia showed no difference when compared to hyponatremia due the other causes, except the fact that the portion of female patients was higher (73.6% vs 64.6%, p<0.001), mean age was older (74.7 vs 69.9 years-old, p<0.001), and incidence of cerebrovascular accident was also higher (19.8% vs 6.5%, p<0.001). CONCLUSION: The use of thiazide is increasing and hence thiazide-induced hyponatremia is also increasing. This is thought to be particularly related to the increase of thiazide-combined drugs. Thiazideinduced hyponatremia shows a higher incidence in old age, female sex and those who have a history of a cerebrovascular event. Hence more caution is needed when using thiazide diuretics as antihypertensives, and plasma sodium levels should be monitored carefully.

Acute Renal Failure Complicated by Valaciclovir in a Patient with IgA Nephropathy / 대한신장학회지

Valaciclovir is L-valyl ester of acyclovir which has the antiviral effect against herpes zoster virus and Cytomegalovirus. Its adverse effects were reported as nephrotoxicity and neurotoxicity. Although the mechanism of nephrotoxicity of valaciclovir is indeterminate, several hypotheses such as obstructive uropathy and interstitial nephritis have been suggested. We experienced a 54-year-old female patient with IgA nephropathy who developed acute renal failure after taking valaciclovir. She did not develop either central neuropathy or respiratory muscle weakness. The serum creatinine was normalized after 6 days by withdrawal of valaciclovir and hydration. When we use valaciclovir in the elderly or patients with preexisting renal disease, we should monitor the renal function carefully.

Association of Depression with Inflammation and Cardiovascular Risk Factors in End Stage Renal Disease Patients on Hemodialysis / 대한신장학회지

PURPOSE: Depression is associated with increased inflammation and cardiovascular disease. And in patients with end stage renal disease (ESRD), depression is a common problem and cardiovascular disease is the main cause of death. The aim of this study is to investigate the association of depression with various inflammatory markers and with some cardiovascular risk factors in ESRD patients on hemodialysis METHODS: 53 patients with ESRD on maintenance hemodialysis were divided into depressive symptom (BDI> or =11) group and control (BDI < 11) group by the 21-items Becks depression inventory (BDI). We collected patients characteristics and laboratory measurements by medical records. And then, we measured the levels of IL-10 and TNF-alpha a and analyzed the genotype of IL-10 and TNF-alpha a promoter area. RESULTS: The levels of TNF-alpha, CRP and ferritin were significantly higher in depressive symptom group (p=0.001, 0.04, 0.02) and IL-10 concentration tended to be lower in depressive symptom group (p= 0.05). The prevalence of left ventricular hypertrophy was higher in depressive symptom group than in the control group (44% vs 9%, p=0.01). GG genotype known as high IL-10 producer was less common in depressive symptom group than in control group (8% vs 36%, p=0.039). CONCLUSION: Increased inflammation, high left ventricular hypertrophy prevalence and low ejection fraction were observed in depressive hemodialysis patients. Further prospective study is needed to clarify the role of depression in the development of inflammation and cardiovascular disease in ESRD patients.

Is Serum Cystatin-C a Useful Marker Predicting the Initiation of Maintenance Dialysis? / 대한신장학회잡지

PURPOSE: Cystatin-C is produced at a constant rate, and has been known to be unaffected by non-renal factors. However, there are limited data on its superiority to serum creatinine as a marker of renal function in ESRD population. The aims of our study were to compare serum cystatin-C and serum creatinine with estimated GFR in ESRD patients at the initiation of dialysis, whether the non-renal factors may influence on serum cystatin-C levels, and whether serum cystatin-C may be a useful marker of the start of dialysis. METHODS: This study was cross-sectional about 163 ESRD patients. We measured serum cystatin-C and serum creatinine levels at the initiation of dialysis, and determined GFR from 24 hour urine collection [G (Ccr)], Cockcroft-Gault [G (C&G)], and the modification of diet in renal disease [G (MDRD)] formula. We considered age, gender, body weight and diabetic nephropathy as non-renal factors. RESULTS: The mean serum cystatin-C was 5.0+/-0.9 mg/dL, serum creatinine 11.4+/-5.9 mg/dL, G (Ccr) 5.0+/-2.9 mL/min/1.73m2, G (C&G) 7.5+/-3.1 mL/min/1.73m2, G (MDRD1) 5.7+/-2.9 mL/min/1.73m2, and G (MDRD2) 5.5+/-2.5 mL/min/1.73m2. We found significant correlation between estimated GFR and serum cystatin-C. However, comparing to serum creatinine, serum cystatin-C had no merits in estimating renal function and in predicting urgent hemodialysis. In the multivariate linear regression models, serum cystatin-C had no significant correlation with gender, body weight, and diabetic nephropathy, but decreased with the age. CONCLUSION: Serum cystatin-C is not superior to serum creatinine for estimating renal function and predicting urgent hemodialysis in ESRD patients. Besides, serum cystatin-C seems to be influenced by non-renal factors, age.

A Case of Hypernatremia by Folk Remedies in a CRF Patient / 대한신장학회잡지

We report a case of chronic hypernatremia caused by excessive salt intake as folk remedies for three months. The patient had chronic tubulointerstitial nephritis (CTIN), but without documented cognitive or psychiatric disorders. She presented with severe hypernatremia 189 mmol/L and general weakness. Fluid therapy was done initially with isotonic and then with 0.45% hypotonic saline until serum sodium level reached to 157 mmol/L. Finally hemodialysis was supplemented to achieve normal serum sodium level, and she recovered without any sequelae. This report might be the first case of chronic hypernatremia due to voluntary ingestion of excessive salt in an adult patient with CTIN but without cognitive or psychiatric disorders.

Asymptomatic Cryptococcus and Subsequent Symptomatic Tuberculosis Infection in a Renal Transplant Patient / 대한이식학회지

Cryptococcus is an important opportunistic pathogen of fungal infection after organ transplantation. And, tuberculosis is also a major cause of infection in immunocompromised patients. We experienced a case of asymptomatic cryptococcal pulmonary infection detected by routine chest X-ray in a renal transplant patient, and a subsequent development of symptomatic multi-drug resistant pulmonary tuberculosis during oral fluconazole treatment. For the appropriate infection control, we should make the thorough evaluation in immunocompromised organ-transplant patients.

Eosinophilic Peritonitis Followed by Acute Colonic Pseudo-obstruction (Ogilvie's syndrome) in an ESRD Patient on CAPD / 대한신장학회잡지

Acute colonic pseudo-obstruction (Ogilvie's syndrome) is characterized by massive dilatation of the colon with no sign of mechanical obstruction. We report a case of eosinophilic peritonitis with severe abdominal pain followed by acute colonic pseudo- obstruction in an ESRD patient on CAPD. The intravenous administration of neostigmine, an acetylcholinesterase inhibitor, resulted in safe and effective colonic decompression in our patient. In case patients with acute colonic pseudo-obstruction do not respond to conservative therapy, treatment with neostigmine can be considered even for patients on dialysis.

The Characteristics and Related Factors with Severe Uremic Pericarditis / 대한신장학회잡지

BACKGOUND: Although the incidence has decreased markedly, mortality from uremic pericarditis still remained high at 8-10% due to hemodynamic compromise. Moreover, it is difficult to diagnose and discriminate from other causes of pericarditis such as tuberculous pericarditis in its early stage. The aim of this study was to analyze the factors that were related to the development of uremic pericarditis and factors that could distinguish it from other causes of pericarditis. METHODS: Eighteen patients who received pericardiocentesis due to uremic pericarditis from 1996 to 2005 in Korea university hospital were enrolled. All patients were diagnosed as severe uremic pericarditis by echocardiography. And as a comparison group, 37 patients with tuberculous pericarditis and 20 patients with malignant pericarditis were also enrolled. Analysis of the factors that were related to the development of uremic pericarditis or comparison of clinical, biochemical factors in uremic, tuberculous or malignant pericarditis were also done. RESULTS: In uremic pericarditis, the proportion of patients with peritoneal dialysis was higher (55.6%). The amount of pericardial effusion showed a positive correlation with the duration of dialysis, whereas showed negative correlation with hemoglobin and cholesterol levels. Pericardial fluid ADA was significantly higher in tuberculous pericarditis and pericardial fluid glucose was higher in uremic pericarditis. No specific factors that were related to the development of pericardial tamponade were identified. CONCLUSION: The development of severe uremic pericarditis might be related to poor nutritional status. In the early stage, ADA and glucose levels in pericardial fluid could be useful in distinguishing uremic pericarditis from tuberculous pericarditis. Prospective studies that enroll large patient population can be helpful in identifying factors that are related to the development of uremic pericarditis or tamponade.

Requirement of ERK Activation in Hypoxia Induced Caspase Activation and Apoptosis of Cultured Tubular Cells / 대한신장학회잡지

BACKGOUND: Renal tubular epithelial cells are primary target for hypoxic injury. Hypoxia induced tubular cell apoptosis has been reported previously and thought to be important mechanism of renal dysfunction in ischemic ARF, but precise signaling mechanisms need to be defined. The aim of this study is to clarify intracellular signaling mechanism mediating apoptosis by hypoxic stimuli in cultured tubular cells. METHODS: HK-2 cells were placed in hypoxic chamber (O2<1%) for 24 hrs in minimal essential medium. DNA fragmentation was detected by Hoechst 33342 stain and FACS. The activation of caspase was measured by fluorometry and activations of p-38, ERK, and JNK were examined by western blot analysis. RESULTS: Hypoxia induced caspase 3 activation and apoptosis at 24 hrs and this was accompanied by increased phosphorylation of p-38, ERK1/2, and JNK. Pretreatment of p-38 inhibitor (SB 203280) and JNK inhibitor (SP600125) did not afftect the activation of caspase 3 and apoptosis but inhibition of ERK1/2 by PD98059 resulted in partial inhibition of caspase 3 and apoptosis induced by hypoxia. CONCLUSION: ERK 1/2 activation can be an upstream signal in hypoxia induced caspase 3 activation and apoptosis in tubular cells.

A Case of Idiopathic Erythrocytosis in a CAPD Patient / 대한신장학회잡지

We have experienced a case of idiopathic erythrocytosis developed in a patient with end stage renal disease who had switched to CAPD from hemodialysis. Hemoglobin levels gradually increased from 8 to 19.0 mg/dl, resulting in various symptoms from hyperviscosity during the first 2 months after the initiation of CAPD. There were no other possible causes of secondary erythrocytosis, such as hypoxia, erythropoietin -producing tumor or acquired cyst. Serum level of IGF-1 was above the normal range in contrast with low serum levels in CAPD patients with anemia. Increased IGF-1 levels may possibly influence on the development of erythrocytosis in this case.

Association of IL-10 genotypes with cardiovascular risk factors in patients with hemodialysis / 대한내과학회지

BACKGROUND: Chronic systemic inflammation in ESRD patients due to uremia and hemodialysis procedure itself comes into notice as a main factor for premature mortality secondary to rapid progressing atherosclerosis. Various pro-inflammatory cytokine, known to mediate these reaction of malnutrition, inflammation and atherosclerosis, are regulated by anti-inflammatory cytokine, such as IL-10. Quantitative production of IL-10 shows interindividual variability determined genetically by polymorphisms of promotor gene. The aim of this study was to measure the degree of IL-10 synthesis in ESRD patients treated with hemodialysis and evaluate the association with genotypes and cardiovascular risk factors. METHODS: The IL-10 genotypes for polymorphic bases at position at -1082 was determined in 66 chronic hemodialysis patients and 98 healthy subjects using highly specific PCR and the lipopolysaccharide (LPS)-stimulated IL-10 (sIL-10) release from whole blood were measured by ELISA. RESULTS: The distribution of the IL-10 genotypes in hemodialysis patients were similar to the general population, but the proportion of A allele in hemodialysis group was significantly higher (72.3% vs 59.8%, p=0.05). sIL-10 concentration were lower in hemodialysis patients compared with normal control (21.1 pg/mg vs 36.1 pg/mg, p=0.001) and both groups showed same relationship of sIL-10 with genotypes, that AA type was low producer. In multiple regression analysis, sIL-10 of normal group correlated negatively with age, creatinine, uric acid and existence LVH, and positively with albumin, hemoglobin. On the other hand, lower albumin, lower ejection fraction on echocardiography and existence of left ventricular hypertrophy were associated with higher sIL-10 in hemodialysis group. CONCLUSION: Polymorphisms by IL-10 genotypes were associated with production of IL-10 by endotoxin stimulation, and sIL-10 was lower in hemodialysis patients than in normal control. According to relation of sIL-10 with cardiovascular risk factors such as existence LVH, ejection fraction and malnutrition, it could be suggested that sIL-10 is useful marker in evaluating the risk of cardiovascular events.

A Case of lambda-type Light Chain Deposition Disease Manifested as Acute Renal Failure and Multiple Organ Dysfunction by Embolic Events / 대한신장학회잡지

Light chain deposition disease is caused by systemic paraprotein deposition resulting from monoclonal plasma cell dyscrasia. It is usually characterized rapidly progressive renal failure and multiple organ dysfunctions. Besides deposition of light chain, it can lead to multiple organ dysfunctions due to hyperviscosity syndrome. We experienced a case of 54-year-old man who presented as an acute renal failure, and elevation of liver enzyme. Radiologically, there was no abnormal finding except enlargement of both kidney in abdominal sonogram. Globulinuria was noticed on 24 hrs-urine study. The histologic findings of kidney showed lambda chain deposits in basement membrane of tubules and glomeruli, interstitium, and vessel walls. On 10th day of hospitalization, he developed sudden hypoxia that was not corrected by oxygen supplementation, and focal neurologic signs accompanied with a change of consciousness. We report a case of light chain deposition disease manifested as an acute renal failure and liver enzyme elevation with suspicious multiple organ embolic events later.