Treatment outcomes for idiopathic sudden sensorineural hearing loss in dialysis patients.

Idiopathic sudden sensorineural hearing loss (ISSNHL) is challenging for both nephrologists and otolaryngologists treating patients undergoing dialysis. This single-center, retrospective, observational study investigated the treatment outcomes of patients with ISSNHL undergoing dialysis, enrolling 700 patients (47 undergoing and 653 not undergoing dialysis) diagnosed with ISSNHL between January 2005 and December 2021 at Asan Medical Center, Republic of Korea. To balance pre-existing clinical characteristics, 1:5 propensity score matching (PSM) was performed with the patients who were not undergoing dialysis. Treatment included high-dose systemic steroid therapy or intra-tympanic steroid injections. The pure tone average of the groups was compared before and 2 weeks and 2 months after treatment. The hearing-improvement degree was evaluated using Siegel's criteria. Before PSM, age, prevalence of diabetes or hypertension, initial hearing threshold at each frequency level (0.5, 1, 2, and 4 kHz), and treatment strategies exhibited significant between-group differences. However, in the PS-matched cohort, none of the confounders showed significant between-group differences. Two months after steroid treatment, the non-dialysis patient group demonstrated significantly higher average improvement in pure tone audiometry (P = 0.029) and greater percentage of complete response according to Siegel's criteria. This study suggests that treatment outcomes for ISSNHL are significantly poorer for patients undergoing than for those not undergoing dialysis.

No difference in follow-up estimated glomerular filtration rate between hypertensive and matched nonhypertensive kidney donors.

BACKGROUND: According to current guidelines, kidney donor candidates with controlled hypertension using 1 or 2 antihypertensive drugs may be considered as donor. However, this recommendation is based on the study that antihypertensive drug was initiated in mainly "after donor registration" and this may be white-coat hypertension because of donation-related anxiety. We compared the follow-up eGFR between kidney donors with preexisting hypertension and matched nonhypertensive donors. METHODS: This single-center retrospective study classified 97 living hypertensive donors previously receiving antihypertensive drugs into two groups: 1 drug group (61 donors) and 2 drugs group (36 donors). We compared the follow-up eGFR between each donor previously receiving antihypertensive drugs and three matched nonhypertensive donors in terms of age, sex, and follow-up duration. RESULTS: At a mean (range) of 51 months (12-214) in the 1 drug group, and 54 months (12-175) in the 2 drugs group after donation, there was no significant difference in follow-up eGFR between hypertensive donors previously receiving antihypertensive drugs and matched controls in each group and in total donors. There was no difference in the incidence of the patients with follow-up eGFR<45mL/min/m2 in each group and their matched controls. Multiple linear regression analysis showed that baseline eGFR was the only independent predictor for the final follow-up eGFR in the total donors. CONCLUSION: Our results support the current guidelines that donor candidates with controlled hypertension using 1 or 2 antihypertensive drugs may be considered as donors, and may increase the strength of this recommendation.

Percutaneous pericardial catheter drainage for symptomatic uremic pericardial effusions with narrow safety margins.

BACKGROUND: Percutaneous pericardial catheter drainage (PCD) for pericardial effusion is generally known to be limited by the high risk associated with effusions that are less than 10 mm thick. The objective was to report cases who underwent percutaneous PCD for symptomatic uremic pericardial effusions, which were less than 10 mm thick after cardiologist declined to perform the PCDs because of the narrow safety margins. MATERIALS AND METHODS: Thirteen consecutive cases (11 patients) (median age, 56 years, range, 31-83) with symptomatic uremic pericardial effusion (thickness <10 mm) affecting the pericardial space anterior to the right ventricle underwent ultrasound- and fluoroscopy-guided percutaneous PCD between September 2015 and April 2022. Information regarding the clinical criteria, echocardiographic features, PCD details, nature of effusion, and outcomes, including success and complications were retrospectively evaluated. RESULTS: Pigtail catheter (8.5-Fr) insertion was successful for all patients, with a median procedure time of 7 minutes (range 4~12) without procedure-related complications. The median amount of drainage on the day of PCD was 700 mL (range, 250-1100). The median duration of catheter indwelling was 5 days (range, 1~32). In one case, the catheter was removed after 1 day due to chest pain. For all patients, pericardial effusion evacuation was achieved with relief of associated symptoms, representing 100% clinical success. CONCLUSION: Percutaneous PCD may be safely performed for patients with symptomatic uremic pericardial effusions and narrow safety margins of less than 10 mm.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding.

BACKGROUND/AIMS: The most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy. METHODS: In this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed. RESULTS: Before propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120). CONCLUSIONS: We do not recommend desmopressin administration before kidney biopsy.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding.

BACKGROUND/AIMS: The most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy. METHODS: In this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed. RESULTS: Before propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120). CONCLUSIONS: We do not recommend desmopressin administration before kidney biopsy.

Transrenal Hemodialysis Catheter Insertion and Replacement in Patients with Upper Extremity Central Venous Access Exhaustion.

PURPOSE: Patients undergoing long-term hemodialysis may suffer upper extremity central venous access failure and require an alternative route. This study aimed to evaluate the safety and efficacy of transrenal hemodialysis catheter insertion/replacement in patients with upper extremity central venous access failure. MATERIALS AND METHODS: A multicenter retrospective cohort study was made of transrenal hemodialysis catheter insertion/replacement performed between 2014 and 2020. The history of renal replacement therapy and central venous catheters and the technical details of transrenal hemodialysis catheter insertion/replacement, patency, removal and complications were obtained for all patients. RESULTS: Six insertion and four replacement procedures involving transrenal hemodialysis catheters were evaluated in six patients (M:F = 3:3; median age, 49.5 years). Percutaneous transrenal (right:left = 1:5) hemodialysis catheter insertion was technically successful without complication in all six patients. In two patients, the tract was not lost because the safety guidewire was still in place, so no second puncture was required. The mean procedure time was 33.0 ± 9.2 min. The mean primary patency duration was 107.3 ± 70.9 days. During the mean follow-up duration of 141.2 ± 137.1 days, four hemodialysis catheter replacement procedures were successfully performed for catheter malfunction (n = 2) and dislodgement (n = 2). Catheter removal was successfully performed in four patients after confirming normal coagulation, followed by subsequent renal replacement therapy. CONCLUSION: Percutaneous insertion/replacement of transrenal hemodialysis catheters is feasible, safe, and effective when upper extremity central venous access is exhausted, and the catheters can be maintained for a reasonable period of time. LEVEL OF EVIDENCE: Level 4, Case Series.

Renal Recovery After Liver Transplantation Alone in Patients With Liver Cirrhosis and Severe Chronic Kidney Disease With Normal Kidney Size.

BACKGROUND: Most guidelines recommend simultaneous liver-kidney transplantation (SLKT) in patients with liver cirrhosis (LC) and severe chronic kidney disease (CKD) over liver transplantation alone (LTA). CKD, however, is not irreversible. This study evaluates the reversibility of kidney disease after LTA based on kidney size. MATERIALS AND METHODS: In this single-center retrospective study, we classified 90 patients with LC and severe CKD into 3 groups: the normal kidney (NK)-LTA group (n=39), small kidney (SK)-LTA group (both kidneys <9 cm at the time of LTA, n=40), and SK-SLKT group (n=11). RESULTS: The NK-LTA group had a lower percentage of hepatocellular carcinoma and a higher pre-liver transplantation (LT) estimated glomerular filtration rate. This group, however, was older, received livers from a higher percentage of deceased donors, and had a higher Child-Pugh score. Renal recovery, defined as the return of creatinine to their baseline, or a persistent change from baseline but not persistent (≥3 months) need for renal replacement therapy after LT, was found in 79% in the NK-LTA group, which was higher than 7.5% in the SK-LTA group. Renal and patient survival was found in 56% of the NK-LTA group, which was higher than 2.5% of the SK-LTA group. CONCLUSIONS: There is a high percentage of renal recovery in the NK-LTA group, and accordingly, this does not justify SLKT, since this would result in a "waste" of kidneys. Therefore, KT after LT is recommended over SLKT for the LC patients with NK size.

Long-Term Outcome of Live Kidney Donation in South Korea.

BACKGROUND Kidney donors may be at increased risk for end-stage renal disease (ESRD) as well as cardiovascular and all-cause mortality. In particular, data on long-term safety after kidney donation in Asian populations are lacking. We aimed to assess the safety of live kidney donation in Korean donors by using a matched control group. MATERIAL AND METHODS We conducted a retrospective cohort study using a hospital-based database (Asan Medical Center, Seoul, Korea) and a control group from the national health insurance claims database in South Korea. We analyzed the health status of 1608 kidney donors who underwent donation between September 1990 and December 2015, and we compared their characteristics with those of matched 6426 non-donors (1: 4 ratio). We also measured the glomerular filtration rate (GFR) with 5¹Cr EDTA and urinary albumin excretion and assessed the prevalence of hypertension, diabetes, and general health status in 200 volunteer donors. RESULTS Mortality was significantly lower in kidney donors compared with the matched controls (130.2 vs. 185.4 per 100,000 person-years, P=0.02). There was no significant difference in mortality if a donor had hypertension or was a current smoker at the time of donation. There was also no significant difference in ESRD (43.1 vs. 35.2 per 100,000 person-years, P=0.07) between the 2 groups regardless of hypertension and smoking status. Among the 200 donors with measured GFR, 11.5% had GFR values <60 ml/min/1.73 m² at 9.4±5.3 years after donation. Older age (P=0.001) and female sex (P=0.021) were significantly associated with GFR values <60 mL/min/1.73 m². CONCLUSIONS Mortality and ESRD were uncommon in carefully selected kidney donors. However, donors with pre-existing risk factors should be followed up more closely to ensure long-term safety.

Prevalence and risk factors of baclofen neurotoxicity in patients with severely impaired renal function.

BACKGROUND/AIMS: The most common adverse effect of baclofen, used for managing hiccups and spasticity, is neurotoxicity. As baclofen is primarily excreted by the kidneys, neurotoxicity is more likely to occur in patients with chronic kidney disease (CKD). We evaluated the risk factor for baclofen neurotoxicity and the recommended dosage for patients with severe CKD. METHODS: In this single-center retrospective study, we classified 401 patients with CKD as stage 4 (n=174), non-dialysis stage 5 (n=97), and on-dialysis (n=130). RESULTS: The prevalence of baclofen-induced neurotoxicity in patients with severe CKD was 7.0% (28 of 401 patients). There was no significant difference in the presence of neurotoxicity when the patients were classified as CKD stage 4, stage 5, and dialysis patients. There were significant differences in serum albumin levels and the presence of diabetic nephropathy between the patients with neurotoxicity and those without. The results from a multiple logistic regression analysis showed that serum albumin was independently associated with baclofen neurotoxicity (p=0.007). The minimum daily dose for baclofen neurotoxicity was 10mg, 10mg, and 5mg in patients with CKD stages 4 and 5, and dialysis, respectively. CONCLUSIONS: In this study, the prevalence of baclofen-induced neurotoxicity in patients with severe CKD was 7.0%. Serum albumin was identified as an independent risk factor for neurotoxicity. We recommend initially administering a daily dose of 7.5mg for patients with severe CKD stages 4 and 5, and a daily dose of 2.5mg for patients receiving dialysis.

Usefulness of mid-week hemoglobin measurement for anemia management in patients undergoing hemodialysis: a retrospective cohort study.

BACKGROUND: Short-term hemoglobin (Hb) variability related to volume status is observed in chronic kidney disease (CKD) patients receiving hemodialysis (HD). Given the lack of studies regarding outcomes according to the day of Hb sampling, the existing guidelines do not strongly recommend regarding measurement timing. Pre-dialysis mid-week sampling (Wednesday and Thursday) is preferable to minimize short-term Hb variability, although numerous HD centers perform early-week sampling (Monday and Tuesday). The different measurement days may influence the prescribed dose of erythropoiesis-stimulating agent (ESA) and related patient outcomes. We investigated changes in Hb levels and ESA doses according to the Hb measurement day among HD patients. METHODS: Starting September 2013, the day for pre-dialysis Hb measurement at the Asan Medical Center was changed from early-week days to mid-week days. This single-center retrospective study evaluated medical records of 92 patients who received maintenance HD between September 2012 and August 2014. RESULTS: There was no significant difference in the mean Hb levels between early-week days and mid-week days (10.71 ± 0.06 g/dL vs. 10.78 ± 0.47 g/dL, p = 0.105). However, the mean doses of darbepoetin-α on early-week days were higher than those on mid-week days (175.4 ± 72.5 µg/month vs. 163.7 ± 83.6 µg/month, p = 0.022). The mean doses of intravenous iron hydroxide sucrose for early-week measurements were also higher than those for mid-week measurements (623.0 ± 489.0 mg/year vs. 447.0 ± 505.2 mg/year, p = 0.001). The mean interdialytic weight gains were 2.81 ± 0.82 kg on early-week days and 1.99 ± 0.61 kg on mid-week days (p < 0.001). CONCLUSIONS: Compared with early-week measurements, mid-week pre-dialysis Hb measurements were significantly associated with lower ESA doses without a change in Hb levels.

Comparison of Clinical Outcomes Between Preemptive Transplant and Transplant After a Short Period of Dialysis in Living-Donor Kidney Transplantation: A Propensity-Score-Based Analysis.

BACKGROUND The permissible extent of pretransplant dialysis for patient and allograft survival is unclear. We assumed that a short period of dialysis before living donor kidney transplantation (LDKT) will show the similar results as preemptive kidney transplantation (PKT). MATERIAL AND METHODS We retrospectively evaluated the outcomes of LDKT according to pretransplant dialysis duration in both unmatched cohorts (n=1984) and propensity-score-matched cohorts (n=986) cohorts. The primary study endpoint was post-transplantation patient survival and death-censored graft survival (DCGS) according to the duration of pretransplant dialysis by 19 months which was the best cutoff value to differentiate clinical outcomes with the use of the time-dependent area under the curve. RESULTS Of 1984 patients with LDKT at our center between January 2005 and September 2016, PKT was performed in 429 patients. The durations of pretransplant dialysis were <19 months in 962 recipients and ≥19 months in 593 recipients. There was no significant difference in mortality and DCGS between PKT and non-PKT recipients with pretransplant dialysis of <19 months. Patient survival (P=0.024) and DCGS (P=0.001) were worse in non-PKT recipients with pretransplant dialysis of ≥19 months. In the matched cohort, DCGS was significantly lower in non-PKT recipients with pretransplant dialysis of ≥19 months (P=0.037). It is likely that the incidence of biopsy-proven acute rejection was higher in this group (P=0.083). CONCLUSIONS Patient survival and DCGS were worse when the pretransplant dialysis duration was ³19 months in a propensity-score-matched LDKT cohort.

Plasma Neutrophil Gelatinase-Associated Lipocalin as a Marker of Tubular Damage in Diabetic Nephropathy.

BACKGROUND: An increase in neutrophil gelatinase-associated lipocalin (NGAL) indicates tubular injury. Diabetic nephropathy causes typical changes in the kidney, characterized by glomerulosclerosis and eventual tubular damage. We validated the usefulness of plasma NGAL (pNGAL) as a biomarker of tubular damage in patients with diabetic nephropathy. METHODS: We included 376 patients with diabetes mellitus (260 patients with chronic renal insufficiency who had not received hemodialysis and 116 hemodialyzed due to diabetic nephropathy) and 24 healthy controls. Patients with chronic renal insufficiency were divided into three groups according to urinary albumin excretion (UAE) levels. pNGAL levels were measured using the Triage NGAL test (Alere, San Diego, CA, USA) and were compared between groups. We also examined whether pNGAL level was related to the degree of albuminuria and cystatin C-based glomerular filtration rate (GFR). RESULTS: Mean pNGAL levels of the healthy controls, chronic renal insufficiency patients with diabetes mellitus, and hemodialyzed patients were 61.9±5.3 ng/mL, 93.4±71.8 ng/mL, and 1,536.9±554.9 ng/mL, respectively. pNGAL level increased significantly in patients with severe albuminuria (P<0.001) and had a moderate correlation with the degree of albuminuria (r=0.467; P<0.001) and GFR (r=0.519; P<0.001). Multivariate regression analysis showed that the pNGAL level was associated with tubular damage independent of patient age, sex, and GFR. CONCLUSIONS: pNGAL level independently reflects the degree of tubular damage in patients with diabetic nephropathy. Measurement of pNGAL, combined with UAE, would enable simultaneous, highly reliable assessments of tubular damage for such patients.

Presence of Hepatitis B Surface Antibody in Addition to Hepatitis B Core Antibody Confers Protection Against Hepatitis B Virus Infection in Hepatitis B Surface Antigen-negative Patients Undergoing Kidney Transplantation.

BACKGROUND: The American Gastroenterological Association and European Association for the Study of the Liver recommend that hepatitis B surface antigen (HBsAg)-negative and hepatitis B core antibody (anti-HBc)-positive patients who receive immunosuppression should be monitored for hepatitis B virus (HBV) infection regardless of hepatitis B surface antibody (anti-HBs) status. However, anti-HBs may provide protection against infection. To investigate whether the presence of anti-HBs in addition to anti-HBc confers protection, we classified HBsAg(-) kidney transplantation (KT) patients into 4 groups according to anti-HBc and anti-HBs status, and compared the HBV infection rate between the anti-HBc(+)anti-HBs(+) group and the other 3 groups. METHODS: In this single-center retrospective study, we classified 1959 patients into 4 groups: anti-HBc(-)anti-HBs(-) (n = 356), anti-HBc(-)anti-HBs(+) (n = 652), anti-HBc(+)anti-HBs(-) (n = 142), and anti-HBc(+)anti-HBs(+) (n = 809). RESULTS: Hepatitis B virus infection was noted in 31 (1.6%) patients after KT. There was a significant difference in HBV infection rate between anti-HBc(+)anti-HBs(+) (1.2%) and anti-HBc(+)anti-HBs(-) (5.6%) (P < 0.001), but not between anti-HBc(+)anti-HBs(+) and anti-HBc(-)anti-HBs(-) (1.1%) or anti-HBc(-)anti-HBs(+) (1.4%). There was a significant difference in HBV infection rate according to anti-HBs titer, but no difference according to the donor viral profile. Hepatic failure occurred in 1 anti-HBc(+)anti-HBs(-) patient and 1 anti-HBc(+)anti-HBs(+) patient, both of whom died. Hepatocellular carcinoma was noted in 4 anti-HBc(-) patients, but not in anti-HBc(+) patients. CONCLUSIONS: The presence of anti-HBs confers protection against HBV infection. We recommend monitoring for HBV infection after KT in HBsAg(-) anti-HBc(+) anti-HBs(-) patients, but not in HBsAg(-) anti-HBc(+) anti-HBs(+) patients.

Use of fludrocortisone for intradialytic hypotension.

Intradialytic hypotension during dialysis adversely affects a patient's prognosis and increases mortality. We report a case in which intradialytic hypotension that persisted after the administration of midodrine was relieved after the use of fludrocortisone. Administration of 0.2 mg of fludrocortisone occurred 30 minutes before dialysis. We compared 45 sessions of dialysis without fludrocortisone administration and 45 sessions of dialysis with fludrocortisone administration in one patient. The number of times in which systolic blood pressure became lower than 80 mmHg and the number of early terminations of dialysis due to a decrease in systolic blood pressure were higher in the sessions without fludrocortisone administration than in the sessions with fludrocortisone administration (P < 0.05). Fludrocortisone may be helpful for the treatment of intradialytic hypotension that does not respond to midodrine administration.

Effects of Renal Impairment on the Pharmacokinetics and Safety of Udenafil.

Udenafil is a phosphodiesterase-5 inhibitor used to treat erectile dysfunction. Although udenafil is not predominantly eliminated by the kidney, renal impairment can alter its secretion/transport pathways. Drug pharmacokinetics and safety must therefore be assessed in subjects with a renal impairment. We investigated the effects of impaired renal function on the pharmacokinetics and safety of a single 100-mg oral dose of udenafil in a single-dose, open-label, parallel-group study of 31 subjects. Cockcroft-Gault creatinine clearance was used to stratify these subjects into healthy controls (>80 mL·min-1 ) and individuals with mild (50 to ≤80 mL·min-1 ), moderate (30 to ≤50 mL·min-1 ), and severe (<30 mL·min-1 ) renal impairment. Pharmacokinetic measurements and safety assessments indicated that the geometric mean of the area under the concentration-time curve to the last measurement in mildly, moderately, and severely renally impaired subjects was 1.30- (90% CI 1.05-1.60), 1.62- (90% CI 1.28-2.06), and 1.60- (90% CI 1.28-2.01) fold higher, respectively, than the healthy controls. The geometric mean of the maximum observed concentration was 1.41- (90% CI 1.05-1.88), 2.02- (90% CI 1.47-2.79), and 1.65- (90% CI: 1.21-2.24) fold higher, respectively. Significant correlations were observed among the creatinine clearance, oral clearance, and maximum concentration of udenafil (P < .01). All adverse events were mild, and no subject discontinued the study. Udenafil administration was well tolerated in all groups. In view of the clinical relevance of drug exposure, our findings indicate that a dose adjustment of udenafil is warranted in subjects with moderate or severe renal impairment.

Association between afebrile status and in-hospital mortality among adult chronic hemodialysis patients with bacteremia.

AIM: We aimed to compare the in-hospital mortality between febrile and afebrile chronic hemodialysis (HD) patients with bacteremia and analyze the blood culture positive rate according to the C-reactive protein (CRP) level. METHODS: We collected data from 2006 to 2014. One hundred ninety bacteremic events were assigned to the "febrile group" (n = 162) and "afebrile group" (n = 28) based on the presence of fever. Fever was defined as a tympanic temperature >37.5°C or axillary temperature >37.0°C. RESULTS: In-hospital mortality (41.4% vs. 6.1%) was higher; and the interval between admission and blood culture was longer (3 vs. 1 h) in the afebrile group than in the febrile group. The mean reason for blood culture in the afebrile group was a high CRP level. CONCLUSIONS: An afebrile status in HD patients with bacteremia is associated with higher in-hospital mortality. Blood culture and empirical antibiotic administration, irrespective of the fever status, should be considered in HD patients with a CRP ≥ 5 mg/dL.

Salty taste thresholds and preference in patients with chronic kidney disease according to disease stage: A cross-sectional study.

AIM: The present study was performed to evaluate the differences in salty taste thresholds among normal controls and non-dialysis chronic kidney disease (CKD) patients according to disease stage and to evaluate the relationship between salty taste thresholds or preferences and mean spot urine sodium concentrations. METHODS: This cross-sectional study enrolled 436 patients with non-dialysis CKD and 74 normal controls. We evaluated detection and recognition thresholds, salty taste preferences and salt usage behaviours (through a questionnaire) in CKD patients and normal controls. We averaged the three most recent spot urine sodium concentrations and used this 'mean spot urine sodium' value to estimate sodium intake in CKD patients. RESULTS: Detection thresholds of stages 3 and 5 and recognition thresholds of stage 3 CKD patients were higher than those of normal controls. Salty taste preferences of stage 5 and salt usage behaviour scores of stages 4 and 5 CKD patients were lower than those of normal controls. Univariate analysis showed that estimated glomerular filtration rate (eGFR), salt usage behaviour score, salty taste preference, smoking, gender and zinc level were significantly associated with mean spot urine sodium in CKD patients. Multiple regression analysis showed that the eGFR and salty taste preference were independently correlated with mean spot urine sodium. CONCLUSIONS: Education to change salty taste preferences and regular follow up are necessary to decrease salt intake in CKD patients.

Simple method to estimate daily sodium intake during measurement of dialysis adequacy in chronic peritoneal dialysis patients.

BACKGROUND AND OBJECTIVES: Restriction of dietary sodium intake for peritoneal dialysis (PD) patients is recommended, but there is limited information on the measurement and monitoring of sodium intake. We have developed a simple method to estimate daily sodium intake during the measurement of dialysis adequacy in PD patients. METHODS AND STUDY DESIGN: A total of 83 PD patients were enrolled in the study. The patients were divided into two groups based on residual renal function (RRF). We measured total sodium removal and estimated daily sodium intake using dietary recall for one day, during the assessment of dialysis adequacy. RESULTS: There were 39 patients in the RRF(-) group and 44 in the RRF(+) group. In both groups, and all patients, there were significant positive correlations between sodium intake and total sodium removal: RRF(-) group, r=0.598; RRF(+) group, r=0.577; total patients, r=0.595. There were linear relationships between dietary sodium intake and total sodium removal in both groups: RRF(-) group, sodium intake (mg/d) = 19.3 × peritoneal sodium removal (mEq/d) + 211;RRF(+) group, sodium intake (mg/d) = 15.4 × total sodium removal (mEq/d) + 609. All PD patients, sodium intake (mg/d) = 15.6 × total sodium removal (mEq/d) + 646. CONCLUSIONS: The measurement of total sodium removal during the assessment of dialysis adequacy could be an effective and simple method to estimate dietary sodium intake in PD patients. A dietary intake of 2,000 mg of sodium corresponds to a total sodium removal of approximately 87 mEq/d.

Comparison of salt taste thresholds and salt usage behaviours between adults in Myanmar and Korea.

BACKGROUND AND OBJECTIVES: Excessive oral salt intake can induce hypertension. According to previous studies, the prevalence of hypertension is higher in Myanmar than in Korea. We postulated that Myanmar adults had higher salt taste thresholds and eat much saltier food. This study aimed to compare salt taste thresholds and salt usage behaviour scores between adults in Myanmar and Korea. METHODS AND STUDY DESIGN: This cross-sectional study enrolled patients who visited volunteer medical service clinics at Ansung in Korea and Hlegu and Bago in Myanmar in August 2014. We measured the vital signs, heights, and weights of each patient and evaluated detection thresholds, recognition thresholds, and salt preferences. All patients underwent urinalysis and spot urine Na tests. Additionally, they each completed a salt usage behaviour questionnaire. RESULTS: A total of 131 patients were enrolled, including 64 Myanmarese patients and 67 Korean patients. Blood pressure was significantly higher in the Myanmarese than in the Koreans. Detection and recognition thresholds, salt preferences, and spot urine sodium and salt usage behaviour scores were also higher in the Myanmarese than in the Korean subjects. We calculated correlation coefficients between systolic blood pressure and parameters that were related to salt intake. The detection and recognition thresholds were significantly correlated with systolic blood pressure. CONCLUSION: All parameters related to salt intake, including detection and recognition thresholds, salt preference, salt usage behaviour scores and spot urine sodium concentrations, are significantly higher in Myanmarese than in Korean individuals.

Altitude Stress During Participation of Medical Congress.

Medical congresses often held in highlands. We reviewed several medical issues associated with altitude stress especially while physicians have participated medical congress held in high altitude. Altitude stress, also known as an acute mountain sickness (AMS), is caused by acute exposure to low oxygen level at high altitude which is defined as elevations at or above 1,200 m and AMS commonly occurs above 2,500 m. Altitude stress with various symptoms including insomnia can also be experienced in airplane. AMS and drunken state share many common features in symptoms, neurologic manifestations and even show multiple microbleeds in corpus callosum and white matter on MRI. Children are more susceptible to altitude stress than adults. Gradual ascent is the best method for the prevention of altitude stress. Adequate nutrition (mainly carbohydrates) and hydration are recommended. Consumption of alcohol can exacerbate the altitude-induced impairments in judgment and the visual senses and promote psychomotor dysfunction. For prevention or treatment of altitude stress, acetazolamide, phosphodiesterase inhibitors, dexamethasone and erythropoietin are helpful. Altitude stress can be experienced relatively often during participation of medical congress. It is necessary to remind the harmful effect of AMS because it can cause serious permanent organ damage even though the symptoms are negligible in most cases.