Usefulness of Assessing Hemodialysis Adequacy Using the Stop Dialysate Flow (SDF) Method / 대한신장학회잡지

BACKGROUND: K/DOQI guidelines recommend the slow flow method as a standardized method of postdialysis blood sampling for measuring hemodialysis adequacy. However, it is not easy to adopt this method when working in busy renal units where it is often difficult to obtain repeated samples exactly at the specified time. The stop dialysis flow (SDF) method recommended by the Scottish Renal Association since 1998 has the advantage of involving 2 steps only: (1) switch off dialysate flow at the end of hemodialysis without altering the blood pump speed and (2) take a blood sample after 5 minutes from the arterial or venous port. However, there are some limitations to SDF mthod in that it does not allow for tissue rebound after the first 5 minutes postdialysis and cannot be used directly to calculate equilibrated Kt/V (Kt/Veq) using either a 30-minute postdialysis sample. We derived a formula that uses a 5-minute postdialysis BUN sample using the SDF method to estimate the BUN concentration at 30 minutes and investigated if it is useful to assess hemodialysis adequacy using this method. METHODS: A total of 51 patients who had been undergoing hemodialysis in Chonnam National University Hospital and had agreed in joining this study were involved. Patients were randomly selected to 2 groups. Blood samples were obtained immediately before dialysis and at 0, 5, and 30 minutes postdialysis. We calculated the linear relationship between the 5-minute and 30-minute postdialysis samples in group A patients (n=25) and validated this equation using the data from the other group B patients (n= 26). We predicted what the 30-minute BUN concentration would be using the measured value of BUN at 5 minutes and compared directly the value of our estimated 30-minute BUN with the measured 30- minute BUN. RESULTS: There was a tight linear correlation (R2=0.993, p<0.05), between measured 5-minute postdialysis BUN concentrations and measured 30-minute postdialysis BUN concentrations in group A patients. This relationship is described by the linear regression equation: 30-minute BUN concentration=1.05x(5-minute BUN concentraion)+1.04. We used this equation to estimate the 30-minute BUN concentration in group B patients based on the 5-minute postdialysis BUN sample from these patients. And there was a close correlation between estimated and measured 30-minute postdialysis BUN concentration (R2= 0.989, p<0.05). The sensitivity, specificity, positive, and negative predictive values of this equation were high when used to estimate 30-minute urea reduction ratio (URR) greater than 65% (88.9%, 100%, 100 %, and 94.4%, respectively) and 30-minute Kt/Vsp greater than 1.2 (100%, 100%, 100%, 100%, respectively). CONCLUSION: We could estimate 30-minute postdialysis BUN concentration, 30-minute Kt/V, and 30-minute URR exactly using SDF method and linear regression equation derived in this study. The advantage of involving 2 steps only makes SDF method a useful tool in assessing hemodialysis adequacy.

Unilateral Autosomal Dominant Polycystic Kidney Disease with Contralateral Renal Agenesis: A Case Report

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disease. There are some reports in the literature concerning unilateral ADPKD. However, in adults, only a few cases of unilateral ADPKD with agenesis of contralateral kidney have been reported. We present a case of unilateral ADPKD with agenesis of contralateral kidney in a 66-yr-old man. Radiographic images showed the enlarged right kidney with multiple variable-sized cysts and the absence of the left kidney. The diagnosis of ADPKD was confirmed by the family screening. The patient received maintenance hemodialysis for endstage renal disease. We report a case of unilateral ADPKD associated with contralateral renal agenesis in a 66-yr-old male patient with a literature review.

Dalteparin sodium-associated retroperitoneal hematoma in a patient with diabetic nephropathy / 대한내과학회지

Retroperitoneal Hematoma is a rare intraabdominal bleeding occurring in patients with low- molecular weight heparin anti-coagulant therapy. We report a case of dalteparin sodium-associated retroperitoneal hematoma in a 70-year-old man with diabetic nephropathy with review of this condition in the literature. He had been suffered from type 2 diabetes mellitus and hypertension for 15 years. In July 2002, he was admitted to our hospital because of unstble angina and left pleural effusion. He was treated with dalteparin sodium and aspirin for unstable angina. On the second hospital day, he was refered to division of nephrology for diabetic nephropathy. Laboratory data on admission included white blood cell count of 4,500/mm3, hemoglobin 9.6 g/dL, platelet count 294,000/mm3, BUN 58.1 mg/dL, serum creatinine 4.1 mg/dL, blood glucose 178 mg/dL, hemoglobin A1c 5.9%, PT 13.9 sec (INR: 1.09), and aPTT 50 sec. On days 6 through 8, he had lower back pain, lower extremity pain and neuropathy, anemia and hypotension. Abdominal ultrasound showed 6 x 6 cm-sized well marginated mixed echogenic lesion in psoas muscle and fluid collection in retroperitoneal cavity. Magnetic resonance imaging (MRI) showed increased signal intensity and thickening of the right psoas muscle including 4.7 x 2.3 x 2.1 cm-sized cytic lesion and 6.2X5.3X3.7 cm-sized cystic lesion on the lateral portion of right psoas muscle in T2-weighted images. Percutaneous drainage of cystic lesion was performed by right lateral approach. Hemodialysis was begun without heparinization. Abdominal CT showed 5.5X5 cm-sized high attenuated lesion in right psoas muscle and 5X3 cm, 3X2 cm, 4.5 x 2.5 cm, 4 x 2.5 cm-sized heterogenous, slightly high attenuated lesions in the right lower abdomen and cul-de-sac in the scans with no enhancement. He was treated by conservative therapy. He recovered gradually. Patients with kidney diseases receiving low molecular weight heparin (dalteparin, enoxaparin, etc.) should be closely monitored to prevent serious bleeding complications. The possibility of retroperitoneal hematoma should be considered, whenever symptoms including lower back pain, inguinal pain, leg pain, anemia, or hypotension occured during the lower molecular weight heparin anticoagulant therapy. To our knowledge, this is the first reported case of retroperitoneal hematoma in a patient during dalteparin sodium (Fragmin(R)) anticoagulant therapy.

Erectile dysfunction in diabetic nephropathy / 대한내과학회지

BACKGROUND: Erectile dysfunction (ED) is prevalent among patients with diabetes mellitus and impaired renal function. To estimate the prevalence of ED in diabetic nephropathy and to identify its risk factors, we carried out a survey of patients with diabetic nephropathy attending Chonnam University Hospital. METHODS: The presence of ED was assessed among 106 type 2 diabetic patients with microalbuminuria or overt diabetic nephropathy or renal replacement therapy using its self- administered International Index of Erectile Function (IIEF). ED was also classified into five validated severity levels, ranging from none (22-25), mild (17-21), mild/moderate (12-16), moderate (8-11), through severe (5-7). Logistic regression was used to examine associations between ED and other medical conditions. RESULTS: The mean age was 45.30+/-8.57 years in patients without ED and 58.53+/-8.46 years in patients with ED. The prevalence of any level of ED was 72% using IIEF. An independent t-test and chi-square demonstrated age, smoking, smoking duration, degree of nephropathy, coronary heart disease, neuropathy, diabetic foot, and retinopathy to be associated with the presence of any level of ED. Patients with ED had lower serum levels of hemoglobin, albumin, triglyceride, HDL-cholesterol and higher serum levels of BUN in unadjusted analyses compared with patients without ED. A multivariable logistic regression demonstrated age, serum creatinine concentration, and renal replacement therapy to be independently associated with the presence of any level of ED. CONCLUSION: ED is extremely prevalent among type 2 diabetic patients with microalbuminuria or overt diabetic nephropathy or renal replacement therapy. Increased age and serum creatinine concentration, and renal replacement therapy were associated with higher prevalence of ED.

Diabetic Muscle Infarction in a Patient with Continuous Ambulatory Peritoneal Dialysis / 대한신장학회잡지

Diabetic muscle infarction (DMI) is a rare condition occurring in subjects with long-standing complicated diabetes mellitus. We report DMI in a 65-year-old man with type 2 diabetes mellitus undergoing continous ambulatory peritoneal dialysis (CAPD) with review of this condition in the literature. He had been suffered from type 2 diabetes mellitus for 21 years. In 1997, he reached end-stage renal disease and had received on renal replacement therapy with CAPD since then. In June 2002, he presented with sudden and spontaneous onset of severe pain in the right thigh region. He was afebrile, and the right thigh was swollen and tender but not erythematous. Laboratory data on admission included white blood cell count of 15, 800/mm3, hemoglobin 9.0 g/dL, platelet count 264, 000/mm3, BUN 102.3 mg/dL, serum creatinine 9.9 mg/dL, fasting blood glucose 85 mg/dL, postprandial 2 hours blood glucose 162 mg/ dL, hemoglobin A1C 5.84%, ESR 125 mm/h (it was 52 mm/h one month earlier), CRP 18.9 mg/dL, and normal levels of creatinine kinase. Magnetic resonance imaging (MRI) showed asymmetry of the muscle in T1-weighted images and increased signal intensity involving the medial portion of right thigh (adductor longus, adductor magnus, vastus intermedius muscle, etc) in T2-weighted images with no contrast enhancement. Radioisotope venography of the ileo-femoral veins was normal, excluding deep venous thrombosis as a cause. The right thigh was explored surgically and a biopsy taken from the vastus intermedius muscle was consistent with chronically inflammed scar tissue with no evidence of malignancy. A biopsy taken from the vastus intermedius muscle showed hemorrhagic necrosis of skeletal muscle, with lymphcytic infiltration. Most of the blood vessels appeared normal. The swelling resolved spontaneously following a few weeks of bedrest and analgesia. To our knowledge, this is the first reported case of DMI in patients undergoing renal replacement therapy in Korea.

The Efficacy and Safety of Intravenous Iron Sucrose in Hemodialysis Patients / 대한신장학회잡지

BACKGROUND: The objective of the present study was to assess the efficacy and safety of iron sucrose by determining the subsequent change in hemoglobin (Hgb), hematocrit (Hct), transferrin saturation (TAST), serum ferritin values and blood pressures in hemodialysis patients receiving Epoetin. METHODS: A total of 19 adult patients who had been receiving hemodialysis three times a week at Chonnam Natinal University Hospital were assigned. Their Hgb level was less than 10 g/dL and their serum ferritin level was less than 100 ng/mL, and/or TSAT was less than 20%. Iron sucrose was administered as 1,000 mg in 10 divided doses diluted in 100 mL normal saline over the last 60 minutes during hemodialysis with a one-time prior test dose of 20 mg on 10 consecutive dialysis sessions. Iron sucrose dosage was adjusted to 25-100 mg/week depending on serum ferritin level, and TSAT in the following 3 months. Epoetin administration was stopped due to insurance regulation when Hgb level was more than 10 g/dL and Hct level was more than 30 %. To evaluate efficacy of iron sucrose, assessment of serum iron parameters and anemia indices was determined just before the first dose (baseline), at 1 month after the first dose (loading) and then, monthly for 3 months (maintenance). To evaluate safety of iron sucrose, we recorded blood pressure 1 hour before and at the time of completion of iron sucrose injection, and also recorded blood pressure during observation sessions before dialysis and at intervals of 2 hours and 4 hours after starting dialysis. We determined routine serum chemistry and hematologic results at 1 month after the first dose and compared results with those obtained at baseline. RESULTS: 1,000 mg iron surcose injection in 10 divided dose (loading) produced a significant rise in Hgb, Hct, serum iron, serum ferritin, TSAT, MCV and MCH at 1 month after first dose (respectively p<0.001, p<0.001, p<0.01, p<0.001, p<0.01, p<0.01, p< 0.01). During the following maintenance period of 3 months, Hgb, Hct, serrum ferritin, and TSAT level remained more elevated than at baseline respectively. In 19 enrolled patients, we experienced no serious adverse drug reactions and no significant changes in intradialytic blood pressure associated with iron sucrose administration. Serum albumin concentrations was higher at 1 month than at base line and however, changes in other serum chemistry and hematologic results were not statistically significant. CONCLUSION: Intravenous iron sucrose administration is an efficient and safe method to supply iron in end-stage renal disease patients receiving Epoetin with iron deficiency, who are undergoing hemodialysis.

Serum homocysteine concentration in kidney transplant recipients / 대한내과학회지

BACKGROUND: Cardiovascular disease (CVD) after kidney transplantation is a major cause of both graft loss and patient death in kidney transplant recipeints. There are several well known risk factors of CVD, such as hyperlipidemia, hypertension, diabetes melitus, old age and smoking. Non-classic risk factors are acute rejection episode, LVH, C-reactive protein and hyperhomocysteinemia. Homocysteine is an amino acid filtered through the glomerulus and hyperhomocysteinemia is considered as a risk factor of CVD in end-stage renal disease (ESRD) and kidney transplant patients. So homocysteine lowering trials, such as folic acid and vitamine supplement therapy, are being made. We evaluated the prevelance and determinants of hyperhomocysteinemia in kidney transplant recipients. METHODS: We measured serum total homocysteine concentration (tHcy) and its determinants in 21 normal persons, 37 chronic renal failure (CRF) patients with conservative treatment (predialysis) and 48 kidney transplant patients. RESULTS: The prevalence of hyperhomocysteinemia was 4.8%, 83.8% and 45.8% among normal persons, predialysis and kidney tranplant patients, respectively. Among the kidney transplant recipients the prevelence of hyperhomocysteinemia was 18.8% in normal renal function (serum creatitine concentration male: below 1.2 mg/dL, female: below 1.1 mg/dL) group and 59.4% in abnormal renal function group. The tHcy values in kidney transplant patients are significantly lower than those in predialysis patients (16.38+/-6.48 nmol/L vs. 24.68+/-9.01 nmol/L, p < 0.01), but higher than those in normal persons (16.38+/-6.48 nmol/L vs. 8.80+/-2.07 nmol/L, p < 0.01). Among the kidney transplant recipients the tHcy values in normal creatinine group are significantly lower than those in abnormal creatinine group (12.02+/-3.68 nmol/L vs. 18.57+/-6.51 nmol/L, p < 0.01). Using muliple regression analysis, this study showed increased serum creatinine concentration is a major determinant of tHcy concentrations in kidney transplant recipients and hyperhomocysteinemia is not correlated with whole blood trough level of cyclosporin (mean 126.26+/-62.19 ng/mL, range: 26~322 ng/mL) or vitamines supplement therapy. CONCLUSION: In this study the serum homocysteine values in kidney transplant recipients were higher than in normal control group but significantly lower than in CRF patients with conservative treatment. The major determinant for serum homocysteine concentration is a serum creatinine concentration.

Serum CRP level is positively correlated with the cardiovascular disease in dialysis patients / 대한내과학회지

BACKGROUND: Atherosclerosis, a major problem in patients undergoing chronic dialysis treatment, has been characterized as an inflammatory disease. Cardiovascular disease is the major cause of mortality, accouting for approximately half of all deaths in this population. The present study was aimed whether CRP, an important inflammatory marker, might be associated with cardiovascular risk in dialysis patients. METHODS: We performed retrospective study in 77 dialysis patients. Patients were divided into the elevated CRP group (>8 mg/L, n=11) and the normal CRP group (8 mg/L) showed significant higher cardiovascular events (by chi-squre test, p=0.032). BMI, smoking, alcohol, dialysis modality, lipid parameters, BUN, serum creatinine, serum protein, serum albumin and seurm TIBC did not show significant difference between two groups. Correlation between CRP and other biochemical parameters was analysed. Only ESR was positively correlated with CRP. In a subsequent analysis, elevated CRP group had significantly higher cardiovascular risk (by stepwise logistic regression method, odd ratio = 6.59;95% CI, 1.13 to 38.28). CONCLUSION: These results suggest that CRP level is correlated with cardiovascular risk in dialysis patients.

Serum Lipids and Lipoproteins in Patients with Chronic Renal Failure / 대한신장학회잡지

We measured serum lipoprotein (a) [Lp (a)] concentrations in 304 uremic patients treated on predialysis, hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD), and compared them with those in 43 normal controls. The mean values were 46.1mg/dl in predialysis, 35.7mg/dl in HD, 54.7mg/dl in CAPD patients and 17.0mg/dl in controls, respectively. Serum Lp (a) levels were elevated both in the predialysis patients (P<0.001) and in the CAPD patients (P<0.001) compared with those in controls, and were also elevated in the CAPD patients (P<0.01) compared with HD patients. Serum Lp (a) levels tended to be higher in HD patients compared with controls, although these differences did not reach statistical significance. We observed statistically significant positive correlations of Lp (a) to serum levels of total cholesterol (TC) (r=0.279, P<0.01), LDL-cholesterol (r=0.335, P<0.01), and Apo (B) (r=0.352, P<0.01), and significant negative correlation of Lp (a) to serum level of albumin (r=-0.278, P<0.01) in 304 CRF patients. CAPD patients had a more atherogenic lipoprotein profile than did HD patients; besides significantly higher Lp (a) levels (P<0.01), total (P<0.001) and LDL (P<0.001) cholesterol, triglycerides (P<0.05), and apo (B) (P<0.001) were significantly elevated in comparison to HD patients. The marked elevation of serum Lp (a) in patients on CAPD may be due to increased hepatic synthesis as a consequence of the substantial amounts of plasma proteins lost in the dialysate. The increased serum concentrations of Lp (a) may contribute to the high risk for atherosclerosis in end stage renal disease, especially in patients treated by CAPD.