Systemic sclerosis is a connective tissue disease characterized by alterations in microvascular structure and function. In these patients, numerous studies have demonstrated a relationship between capillary morphology and peripheral blood perfusion. Nailfold videocapillaroscopy reveals the peripheral microvascular morphology and thus allows classification and scoring of capillary abnormalities with respect to different microangiopathy patterns (early, active, and late). Laser Doppler f lowmetry and laser speckle contrast analysis can be used to estimate cutaneous blood flow through microvessels and to assess and quantify blood perfusion at peripheral sites. These two methods are also used to identify changes in digital blood perfusion after the infusion of vasodilators.

Hypoglycemia is a major barrier to achieving the glycemic goal in patients with type 2 diabetes. In particular, severe hypoglycemia, which is defined as an event that requires the assistance of another person to actively administer carbohydrates, glucagon, or take other corrective actions, is a serious clinical concern in patients with diabetes. If severe hypoglycemia is not managed promptly, it can be life threatening. Hypoglycemia-associated autonomic failure (HAAF) is the main pathogenic mechanism behind severe hypoglycemia. Defective glucose counter-regulation (altered insulin secretion, glucagon secretion, and an attenuated increase in epinephrine during hypoglycemia) and a lack of awareness regarding hypoglycemia (attenuated sympathoadrenal activity) are common components of HAAF in patients with diabetes. There is considerable evidence that hypoglycemia is an independent risk factor for cardiovascular disease. In addition, hypoglycemia has a significant inf luence on the quality of life of patients with diabetes. To prevent hypoglycemic events, the setting of glycemic goals should be individualized, particularly in elderly individuals or patients with complicated or advanced type 2 diabetes. Patients at high-risk for the future development of severe hypoglycemia should be selected carefully, and intensive education with reinforcement should be implemented.

The Korean Society of Nephrology (KSN) launched a nationwide end-stage renal disease (ESRD) patient registry in 1985 called the Insan Prof. Byung-Suk Min Memorial ESRD Patient Registry. KSN members voluntarily participate in this registry, which has been collecting data through the Internet since 2000. The KSN ESRD patient registry data were reviewed to elucidate the major changes and improvements in dialysis therapy in Korea. The data review revealed: a rapid increase in the number of patients with ESRD; an increase in the number of patients with diabetic nephropathy; a decrease in the proportion of patients undergoing peritoneal dialysis; an increase in the role of private dialysis clinics; an increase in the number of elderly patients undergoing dialysis and the number of patients undergoing long-term dialysis; a decrease in mean blood pressure and an increase in pulse pressure; improvement in anemia treatment; improvement in dialysis adequacy; and improvement in the survival of patients undergoing dialysis. In conclusion, improvements have been made in blood pressure control, anemia treatment, and dialysis adequacy despite increases in the number of elderly patients, diabetic patients, and patients on long-term dialysis during the last two decades in Korea.

Background/Aims: The efficacy of tenofovir disoproxil fumarate (TDF) for the treatment of chronic hepatitis B (CHB) patients following prior treatment failure with multiple nucleos(t)ide analogues (NAs) is not well defined, especially in Asian populations. In this study we investigated the efficacy and safety of TDF rescue therapy in CHB patients after multiple NA treatment failure. Methods: The study retrospectively analyzed 52 CHB patients who experienced failure with two or more NAs and who were switched to regimens containing TDF. The efficacy and safety assessments included hepatitis B virus (HBV) DNA undetectability, hepatitis B envelop antigen (HBeAg) seroclearance, alanine transaminase (ALT) normalization and changes in serum creatinine and phosphorus levels. Results: The mean HBV DNA level at baseline was $5.4{\pm}1.76log_{10}\;IU/mL$. At a median duration of 34.5 months of TDF treatment, the cumulative probabilities of achieving complete virological response (CVR) were 25.0%, 51.8%, 74.2%, and 96.7% at 6, 12, 24, and 48 months, respectively. HBeAg seroclearance occurred in seven of 48 patients (14.6%). ALT levels were normalized in 27 of 31 patients (87.1%) with elevated ALT at baseline. Lower levels of HBV DNA at baseline were significantly associated with increased CVR rates (p < 0.001). However, CVR rates did not differ between TDF monotherapy or combination therapy with other NAs, and were not affected by mutations associated with resistance to NAs. No significant adverse events were observed. Conclusions: TDF is an efficient and safe rescue therapy for CHB patients after treatment failure with multiple NAs.

Background/Aims: Although drug-eluting stents (DESs) effectively reduce restenosis following percutaneous coronary intervention (PCI), they also delay re-endothelialization and impair microvascular function, resulting in adverse clinical outcomes. Endothelial progenitor cell (EPC) capturing stents, by providing a functional endothelial layer on the stent, have beneficial effects on microvascular function. However, data on coronary microvascular function in patients with EPC stents versus DESs are lacking. Methods: Seventy-four patients who previously underwent PCI were enrolled in this study. Microvascular function was evaluated 6 months after PCI based on the index of microvascular resistance (IMR) and the coronary flow reserve (CFR). IMR was calculated as the ratio of the mean distal coronary pressure at maximal hyperemia to the inverse of the hyperemic mean transit time (hTmn). The CFR was calculated by dividing the hTmn by the baseline mean transit time. Results: Twenty-one patients (age, $67.2{\pm}9.6years$; male:female, 15:6) with an EPC stent and 53 patients (age, $61.5{\pm}14.7years$; male:female, 40:13) with second-generation DESs were included in the study. There were no significant differences in the baseline clinical and angiographic characteristics of the two groups. Angiography performed 6 months postoperatively did not show significant differences in their CFR values. However, patients with the EPC stent had a significantly lower IMR than patients with second-generation DESs (median, 25.5 [interquartile range, 12.85 to 28.18] vs. 29.0 [interquartile range, 15.42 to 39.23]; p = 0.043). Conclusions: Microvascular dysfunction was signif icantly improved after 6 months in patients with EPC stents compared to those with DESs. The complete re-endothelialization achieved with the EPC stent may provide clinical benefits over DESs, especially in patients with microvascular dysfunction.

Background/Aims: In the bare-metal stent era, routine follow-up coronary angiography (RFU CAG) was used to ensure stent patency. With the advent of drug-eluting stents (DESs) with better safety and efficacy profiles, RFU CAG has been performed less often. There are few data on the clinical impact of RFU CAG after second- or third-generation DES implantation in clinically stable patients with coronary artery disease; the aim of this study was to examine this issue. Methods: We analyzed clinical outcomes retrospectively of 259 patients who were event-free at 12-month after stent implantation and did not undergo RFU CAG (clinical follow-up group) and 364 patients who were event-free prior to RFU CAG (angiographic follow-up group). Baseline characteristics were compared between the groups. Results: The Kaplan-Meier estimated total survival and major adverse cardiac event (MACE)-free survival did not differ between the groups (p = 0.100 and p = 0.461, respectively). The cumulative MACE rate was also not different between the groups (hazard ratio, 0.85; 95% confidence interval, 0.35 to 2.02). In the angiographic follow-up group, 8.8% revascularization was seen at RFU CAG. Conclusions: RFU CAG did not affect long-term clinical outcome after second- or third-generation DES implantation in clinically stable patients.

Background/Aims: Pleuropulmonary paragonimiasis produces no specific symptoms or radiologic findings, allowing for the possibility of misdiagnosis. We evaluated the specific clinical and pleural fluid features of pleuropulmonary paragonimiasis masquerading as pleural tuberculosis. Methods: We retrospectively analyzed the clinical and radiologic characteristics of 20 patients diagnosed with pleuropulmonary paragonimiasis between 2001 and 2011. Results: In total, 17 patients presented with respiratory symptoms, including dyspnea (30%), hemoptysis (20%), cough (20%), and pleuritic chest pain (15%). Chest radiographs revealed intrapulmonary parenchymal lesions, including air-space consolidation (30%), nodular opacities (20%), cystic lesions (15%), ground-glass opacities (10%), and pneumothorax (5%). A pleural f luid examination revealed eosinophilia, low glucose levels, and high lactate dehydrogenase (LDH) levels in 87%, 76%, and 88% of the patients, respectively. These traits helped to distinguish pleuropulmonary paragonimiasis from other pleural diseases such as parapneumonic effusion, malignancy, and pleural tuberculosis. Conclusions: Pleuropulmonary paragonimiasis is often initially misdiagnosed as other pleural diseases. Therefore, it is important to establish the correct diagnosis. In patients with unexplained pleural effusion living in paragonimiasis-endemic areas, pleural fluid obtained by thoracentesis should be examined to distinguish pleuropulmonary paragonimiasis. When marked eosinophilia, high LDH levels, and low glucose levels are identified in pleural fluid, physicians could consider a diagnosis of pleuropulmonary paragonimiasis.

Background/Aims: Acute exacerbations in chronic obstructive pulmonary disease may be related to air pollution, of which ozone is an important constituent. In this study, we investigated the protein profiles associated with ozone-induced exacerbations in a smoking-induced emphysema model. Methods: Mice were divided into the following groups: group I, no smoking and no ozone (NS + NO); group II, no smoking and ozone (NS + O); group III, smoking and no ozone (S + NO); and group IV, smoking and ozone (S + O). Bronchoalveolar lavage, the mean linear intercept (MLI) on hematoxylin and eosin staining, nano-liquid chromatography-tandem mass spectrometry (LC-MS/MS), and Western blotting analyses were performed. Results: The MLIs of groups III (S + NO) and IV (S + O) ($45{\pm}2$ and $44{\pm}3{\mu}m$, respectively) were significantly higher than those of groups I (NS + NO) and II (NS + O) ($26{\pm}2$ and$23{\pm}2{\mu}m$, respectively; p < 0.05). Fourteen spots that showed significantly different intensities on image analyses of two-dimensional (2D) protein electrophoresis in group I (NS + NO) were identified by LC-MS/MS. The levels of six proteins were higher in group IV (S + O). The levels of vimentin, lactate dehydrogenase A, and triose phosphate isomerase were decreased by both smoking and ozone treatment in Western blotting and proteomic analyses. In contrast, TBC1 domain family 5 (TBC1D5) and lamin A were increased by both smoking and ozone treatment. Conclusions: TBC1D5 could be a biomarker of ozone-induced lung injury in emphysema.

Background/Aims: The aim was to determine which of three sets of metabolic syndrome (MetS) criteria (International Diabetes Federation [IDF], National Cholesterol Education Program Adult Treatment Panel III [ATP III], and European Group for the Study of Insulin Resistance [EGIR]) best predicts the coronary artery calcification (CAC) score in a cross-sectional study. This has not been evaluated in previous studies. Methods: A total of 24,060 subjects were screened for CAC by multi-detector computed tomography. The presence of CAC was defined as a CAC score > 0. The odds ratio for the presence of CAC was analyzed for three different sets of MetS criteria and according to number of MetS components. Results: CAC was observed in 12.6% (3,037) of the subjects. Patients with MetS, as defined by the IDF, ATP III, and EGIR criteria, had a CAC rate of 23.0%, 25.1%, and 29.5%, respectively (p < 0.001). Comparisons of C statistics for multivariate regression models revealed no significant difference among the three sets of criteria. After adjustment for risk factors, the ATP III criteria produced a slightly higher odds ratio for CAC compared with the other criteria, but this difference was not significant. The risk factor-adjusted odds ratio for the presence of CAC increased from 1 to 1.679 as the number of MetS components defined by ATP III increased from 0 to ${\geq}3$ (p for trend < 0.001). Conclusions: The presence of MetS was associated with the presence of CAC. There was no significant difference among the three sets of MetS criteria in terms of the ability to predict CAC. An increase in the number of MetS components was associated with an increased odds of CAC.

Background/Aims: Diabetic cystopathy is a frequent complication of diabetes mellitus. This study assessed the association between the post-voiding residual (PVR) urine volume and diabetic nephropathy in type 2 diabetics with no voiding symptoms. Methods: This study investigated 42 patients with type 2 diabetes who were followed regularly at our outpatient clinic between July 1, 2008 and June 30, 2009. No patient had voiding problems or International Prostate Symptom Scores (IPSSs) ${\geq}12$. An urologist performed the urological evaluations and the PVR was measured using a bladder scan. A PVR > 50 mL on two consecutive voids was considered abnormal, which was the primary study outcome. Results: The mean patient age was $60{\pm}10years$; the IPSS score was $3.7{\pm}3.3$; and the diabetes duration was $11.9{\pm}7.8years$. Seven of the 42 patients (16.7%) had a PVR > 50 mL. The presence of overt proteinuria or microalbuminuria was associated with an increased risk of a PVR > 50 mL (p < 0.01). Patients with a PVR > 50 mL had a significantly lower estimated glomerular filtration rate (eGFR) compared with those with a PVR ${\leq}50mL$ ($59.2{\pm}27.1mL/min/1.73m^2$ vs. $28.7{\pm}23.3mL/min/1.73m^2$; p < 0.001). Multivariate logistic analysis revealed that a lower eGFR (odds ratio, 0.94; 95% confidence interval, 0.88 to 0.99; p = 0.04) was a significant risk factor for a PVR > 50 mL. Conclusions: Patients with diabetic nephropathy had a significantly higher PVR and a lower eGFR was associated with an abnormal PVR.

Background/Aims: Little is known about the efficacy of low-dose transdermal fentanyl (TDF) patches in opioid-naive patients with moderate-to-severe cancer pain. Methods: This study had an open-label, prospective design, and was conducted between April 2007 and February 2009 in seven tertiary cancer hospitals; 98 patients were enrolled. TDF was started using a low-dose formulation ($12.5{\mu}g/hr$), and the dose was adjusted according to the clinical situation of individual patients. Pain intensity, the TDF doses used, and adverse events (AEs) were monitored over 4 weeks. Data were analyzed using the intent-to-treat and per-protocol principles. Results: Of the 98 patients enrolled, 64 (65%) completed the study. The median pain intensity decreased from 6.0 to 3.0 (p < 0.001) at the follow-up visit. The efficacy of low-dose TDF on pain relief was consistent across groups separated according to gender (p < 0.001), age (p < 0.001), metastasis (p < 0.001), previous treatment (p < 0.001), and baseline pain intensity (p < 0.001). The decrease in pain intensity was significantly greater in the severe group compared with the moderate group ($mean{\pm}SD$, $5.10{\pm}2.48$ vs. $2.48{\pm}1.56$; p < 0.001). TDF dose ($27.8{\mu}g/hr$ vs. $24.8{\mu}g/hr$, p = 0.423) and the mean treatment time (7.5 days vs. 7.9 days, p = 0.740) required for pain control were not different between the two pain-intensity groups. Patients had AEs of only mild or moderate intensity; among these, nausea (38%) was the most common, followed by vomiting (22%) and somnolence (22%). Conclusions: Low-dose TDF was an effective treatment for patients with cancer pain of moderate-to-severe intensity. Further randomized trials assessing the efficacy of TDF for severe pain and/or optimal starting doses are warranted.

Background/Aims: Respiratory viruses (RVs) are considered to be important respiratory pathogens in adult patients, and the multiplex reverse transcription-polymerase chain reaction (RT-PCR) test is used frequently in adult patients with respiratory infections. However, clinical data regarding utilization of the multiplex RT-PCR test for RVs are lacking. Methods: We investigated the utilization of the multiplex RT-PCR test for RVs at Chung-Ang University Hospital in Seoul, Korea, between January 2012 and April 2013. Results: During the study period, the multiplex RT-PCR test was performed for 291 adult patients. The test frequency was 4.9% of rapid influenza antigen detection tests and 0.8% of respiratory bacterial culture studies. A turnaround time of < 48 hours was observed in 25.9% of positive tests. Most of the tests were performed for admitted patients (97.9%) with a community-acquired infection (84.2%) during the flu season (82.5%). RVs were detected in 81 of 291 cases (27.8%). The RV positivity rates for community- and hospital-acquired infections did not differ (28.6% vs. 23.9%, p = 0.52). Of 166 patients with pneumonia, 44 (26.5%) had a viral infection. Among the patients with RV-associated pneumonia, an RV other than influenza was detected in 20 patients (45.4%). Conclusions: The multiplex RT-PCR test for RVs was infrequently performed at a tertiary care center, and the test results were often reported late. The test was most often performed for admitted adult patients with community-acquired infections during the flu season. The utilization of multiplex RT-PCR testing for RVs in current clinical practice should be improved.

Background/Aims: To evaluate the impact on mortality of anti-tumor necrosis factor (anti-TNF) treatment of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Methods: We retrospectively reviewed the medical records of 100 RA-ILD patients who visited our tertiary care medical center between 2004 and 2011, identified those treated with an anti-TNF agent, divided patients into non-survivor and survivor groups and evaluated their clinical characteristics and causes of death. Results: A total of 24 RA-ILD patients received anti-TNF therapy, of whom six died (25%). Mean age at initiation of anti-TNF therapy was significantly higher in the nonsurvivor versus survivor group (76 years [range, 66 to 85] vs. 64 years [range, 50 to 81], respectively; p = 0.043). The mean duration of anti-TNF treatment in the non-survivor group was shorter (7 months [range, 2 to 14] vs. 23 months [range, 2 to 58], respectively; p = 0.030). The duration of anti-TNF therapy in all nonsurviving patients was < 12 months. Pulmonary function test results at ILD diagnosis, and cumulative doses of disease-modifying drugs and steroids, did not differ between groups. Five of the six deaths (83%) were related to lung disease, including two diffuse alveolar hemorrhages, two cases of acute exacerbation of ILD, and one of pneumonia. The sixth patient died of septic shock following septic arthritis of the knee. Conclusions: Lung complications can occur within months of initial anti-TNF treatment in older RA-ILD patients; therefore, anti-TNF therapy should be used with caution in these patients.