Mycophenolate mofetil (MMF) is usually prescribed with a reduced fixed dose in Asian kidney transplant recipients (KTRs). However, the clinical efficacy and safety of the fixed dose have not yet been investigated via therapeutic drug monitoring. We evaluated whether reduced fixed-dose MMF is an optimal dosing strategy to achieve the therapeutic target of mycophenolic acid (MPA) exposure in Korean KTRs. Methods: This open-label, prospective study enrolled 50 de novo KTRs prescribed with tacrolimus, corticosteroid, and fixed-dose MMF (1.0–1.5 g/day). The trough level (C0) and area under the curve (AUC0–12 hr) of MPA were measured at 1 and 24 weeks after kidney transplantation (KT). The relationship of body weight (BW)-adjusted MMF dose with MPA C0 and MPA AUC0–12 hr was assessed using linear regression analysis. Results: The initial fixed dose of MMF of 1.44 ± 0.16 g/day was adjusted in 24 patients (48.0%) and then reduced to a mean dose of 1.19 ± 0.31 g/day at 24 weeks after KT. Most patients (≥84.0%) attained the minimum required MPA C0 of 1.0 μg/mL and MPA AUC0–12 hr of 30 μg × hr/mL at 1 and 24 weeks. The BW-adjusted MMF dose demonstrated significant positive correlations with MPA C0 and MPA AUC0– 12 hr at 1 and 24 weeks after KT. Moreover, 14 patients (28.0%) reported MPA-related adverse events that were predictable based on MPA AUC0–12 hr (cutoff level, 46.4 μg × hr/mL). Conclusion: The current reduced fixed-dose MMF strategy can help achieve the therapeutic target of MPA exposure in tacrolimus- treated Korean KTRs during the early posttransplant period.

Background: Calcineurin inhibitor (CNI) toxicity is a significant cause of graft dysfunction in kidney transplant recipients, yet distinguishing it from acute rejection (AR) and acute tubular necrosis (ATN) remains challenging. This study investigated the use of urinary mRNA biomarkers as a noninvasive tool for identifying CNI toxicity. Methods: We retrospectively enrolled 110 kidney transplant recipients and classified them into four groups based on pathological findings: stable graft function (n=35), CNI toxicity (n=25), AR (n=30), and ATN (n=20). Candidate biomarkers were selected using the GEO database. Urinary mRNA was extracted from cell pellets, reverse-transcribed, and quantified by real-time polymerase chain reaction. Results: Estimated glomerular filtration rates were comparable among the CNI toxicity, AR, and ATN groups. Four transcripts (LTF, NNMT, WFDC2, and HIF1A) were identified as candidate biomarkers. Urinary mRNA levels of LTF, NNMT, and HIF1A were significantly lower in the CNI toxicity group than the AR group. NNMT and HIF1A levels were also significantly lower than those observed in the ATN group. In contrast, WFDC2 levels did not differ significantly across groups. A three-gene signature (LTF, NNMT, and HIF1A) effectively differentiated CNI toxicity from AR and ATN (area under the curve [AUC], 0.867;95% confidence interval [CI], 0.787–0.947) and significantly enhanced the diagnostic performance of the clinical variable-based model (AUC increased from 0.776; 95% CI, 0.660–0.892, to 0.934; 95% CI, 0.881–0.986). Conclusions Urinary mRNA levels of LTF, NNMT, and HIF1A may serve as useful biomarkers for identifying CNI toxicity in kidney transplant recipients with graft dysfunction.

Purpose: To investigate the surgical outcomes of endonasal dacryocystorhinostomy with canalicular trephination in patients with canalicular obstruction. Methods: We retrospectively analyzed the medical records of 37 eyes from 32 patients who were diagnosed with canalicular obstruction between May 2010 and July 2022 and underwent endonasal dacryocystorhinostomy with canalicular trephination to evaluate the success rate and complications. Results: In the total patient group, 81.1% achieved complete success in which epiphora completely disappeared, 13.5% had partial success in which epiphora remained but improved, and 5.4% experienced failure in which tearing persisted or worsened. Complications included one case of dacryocystorhinostomy bony opening granuloma and one case of dacryocystorhinostomy bony opening inflammation. Conclusions Endonasal dacryocystorhinosomy with canalicular trephination is an effective method for treating canalicular obstruction, offering a high success rate and few complications. It can be considered before resorting to conjunctivodacryocystorhinostomy, which is a more conventional treatment.

Background: Flow cytometric immunophenotyping of hematolymphoid neoplasms (FCIHLN) is essential for diagnosis, classification, and minimal residual disease (MRD) monitoring. FCI-HLN is typically performed using in-house protocols, raising the need for standardization. Therefore, we surveyed the current status of FCI-HLN in Korea to obtain fundamental data for quality improvement and standardization. Methods: Eight university hospitals actively conducting FCI-HLN participated in our survey.We analyzed responses to a questionnaire that included inquiries regarding test items, reagent antibodies (RAs), fluorophores, sample amounts (SAs), reagent antibody amounts (RAAs), acquisition cell number (ACN), isotype control (IC) usage, positiveegative criteria, and reporting. Results: Most hospitals used acute HLN, chronic HLN, plasma cell neoplasm (PCN), and MRD panels. The numbers of RAs were heterogeneous, with a maximum of 32, 26, 12, 14, and 10 antibodies used for acute HLN, chronic HLN, PCN, ALL-MRD, and multiple myeloma-MRD, respectively. The number of fluorophores ranged from 4 to 10. RAs, SAs, RAAs, and ACN were diverse. Most hospitals used a positive criterion of 20%, whereas one used 10% for acute and chronic HLN panels. Five hospitals used ICs for the negative criterion. Positiveegative assignments, percentages, and general opinions were commonly reported. In MRD reporting, the limit of detection and lower limit of quantification were included. Conclusions This is the first comprehensive study on the current status of FCI-HLN in Korea, confirming the high heterogeneity and complexity of FCI-HLN practices. Standardization of FCI-HLN is urgently needed. The findings provide a reference for establishing standard FCI-HLN guidelines.

Purpose: Managing recurrent inguinal hernias is complex, and choosing the right surgical approach (laparoscopic vs. open) is vital for patient outcomes. This study compared the outcomes of using the same vs. different surgical approaches for initial and subsequent hernia repairs. Methods: We retrospectively analyzed patients who underwent recurrent inguinal hernia repair at Seoul National University Bundang Hospital between January 2014 and May 2023. Patients were divided into the “concordant” and “discordant” groups, comprising patients who underwent same and different approaches in both surgeries, respectively. Preoperative baseline characteristics, index surgery data, postoperative outcomes, and recurrence rates were analyzed and compared. Results: In total, 131 patients were enrolled; the concordant and discordant groups comprised 31 (open, n = 19; laparoscopic, n = 12) and 100 patients (open to laparoscopic, n = 68; laparoscopic to open, n = 32), respectively. No significant differences were observed in the mean operation time (50.5 ± 21.7 minutes vs. 50.2 ± 20.0 minutes, P = 0.979), complication rates (6.5% vs. 14.0%, P = 0.356), or 36-month cumulative recurrence rates (9.8% vs. 9.8%; P = 0.865). The mean postoperative hospital stay was significantly shorter in the discordant than in the concordant group (1.8 ± 0.7 vs. 1.4 ± 0.6, P = 0.003). Conclusion Most recurrent inguinal hernia repairs were performed using the discordant surgical approach. Overall, concordance in the surgical approach did not significantly affect postoperative outcomes. Therefore, the selection of the surgical approach based on the patient’s condition and surgeon’s preference may be advisable.

Background: Considering the interactions between heavy metals, a comprehensive evaluation of the effects of exposure to various types of co-interacting heavy metals on health is required.This study assessed the association between dyslipidemia markers and blood mercury, lead, cadmium, iron, zinc, and nickel levels in residents of an abandoned refinery plant. Methods: A total of 972 individuals (exposed group: 567, control group: 405) living near the Janghang refinery plant in the Republic of Korea were included. Blood mercury, lead, cadmium, iron, zinc, nickel, cholesterol, and triglyceride levels were measured. The combined effect of the six heavy metals on dyslipidemia markers was evaluated using a Bayesian kernel machine regression (BKMR) model and compared with the results of a linear regression analysis. The BKMR model results were compared using a stratified analysis of the exposed and control groups. Results: In the BKMR model, the combined effect of the six heavy metals was significantly associated with total cholesterol (TC) levels both below the 45th percentile and above the 55th percentile in the total population. The combined effect range between the 25th and 75th percentiles of the six metals on TC levels was larger in the exposed group than that in the total population. In the control group, the combined effects of the changes in concentration of the six heavy metals on the TC concentration were not statistically significant. Conclusion These results suggest that the cholesterol levels of residents around the Janghang refinery plant may be elevated owing to exposure to multiple heavy metals.

Purpose: To report a rare case of primary eyelid tuberculosis treated using systemic anti-tuberculosis medications.Case summary: A 30-year-old male presented to our hospital with an upper eyelid mass in the left eye for 1 month. An atypical cystic mass, pale yellow in color with a smooth surface, was observed on the medial side of the left upper eyelid. There were no associated ophthalmic or systemic symptoms. Excisional biopsy of the mass was performed under local anesthesia and histopathological examination revealed chronic granulomatous inflammation with central Langhans-type giant cells. Acid-fast bacilli smear was negative, but polymerase chain reaction for Mycobacterium tuberculosis was positive. There were no significant findings in blood tests and chest radiographs. The patient was diagnosed with primary eyelid tuberculosis and treated with systemic anti-tuberculosis medications for 6 months. There were no complications or recurrences during 1 year of follow-up. Conclusions Although eyelid tuberculosis is rare, early diagnosis through biopsy is important when a granulomatous tuberculosis lesion is suspected. Delayed diagnosis can lead to serious cosmetic and functional complications. Appropriate systemic anti-tuberculosis medications are required to treat these cases.

Purpose: Plasma circulating tumor DNA (ctDNA) could reflect the genetic alterations present in tumor tissues. However, there is little information about the clinical relevance of cell-free DNA genotyping in peripheral T-cell lymphoma (PTCL). Materials and Methods: After targeted sequencing plasma cell-free DNA of patients with various subtypes of PTCL (n=94), we analyzed the mutation profiles of plasma ctDNA samples and their predictive value of dynamic ctDNA monitoring for treatment outcomes. Results: Plasma ctDNA mutations were detected in 53 patients (56%, 53/94), and the detection rate of somatic mutations was highest in angioimmunoblastic T-cell lymphoma (24/31, 77%) and PTCL, not otherwise specified (18/29, 62.1%). Somatic mutations were detected in 51 of 66 genes that were sequenced, including the following top 10 ranked genes: RHOA, CREBBP, KMT2D, TP53, IDH2, ALK, MEF2B, SOCS1, CARD11, and KRAS. In the longitudinal assessment of ctDNA mutation, the difference in ctDNA mutation volume after treatment showed a significant correlation with disease relapse or progression. Thus, a ≥ 1.5-log decrease in genome equivalent (GE) between baseline and the end of treatment showed a significant association with better survival outcomes than a < 1.5-log decrease in GE. Conclusion Our results suggest the clinical relevance of plasma ctDNA analysis in patients with PTCL. However, our findings should be validated by a subsequent study with a larger study population and using a broader gene panel.

Purpose: This retrospective study aimed to determine the number of times the ultrasound-guided attenuation parameter (UGAP) should be measured during the evaluation of hepatic steatosis. Methods: Patients with suspected nonalcoholic fatty liver disease who underwent two UGAP repetition protocols (six-repetition [UGAP_6] and 12-repetition [UGAP_12]) and measurement of the controlled attenuation parameter (CAP) using transient elastography between October 2020 and June 2021 were enrolled. The mean attenuation coefficient (AC), interquartile range (IQR)/median, and coefficient of variance (CV) of the two repetition protocols were compared using the paired t test. Moreover, the diagnostic performances of UGAP_6 and UGAP_12 were compared using the area under the receiver operating characteristic (AUROC) curve, considering the CAP value as a reference standard. Results: The study included 160 patients (100 men; mean age, 50.9 years). There were no significant differences between UGAP_6 and UGAP_12 (0.731±0.116 dB/cm/MHz vs. 0.734±0.113 dB/cm/MHz, P=0.156) and mean CV (7.6±0.3% vs. 8.0±0.3%, P=0.062). However, the mean IQR/median of UGAP_6 was significantly lower than that of UGAP_12 (8.9%±6.0% vs. 9.8%±5.2%, P=0.012). In diagnosing the hepatic steatosis stage, UGAP_6 and UGAP_12 yielded comparable AUROCs (≥S1, 0.908 vs. 0.897, P=0.466; ≥S2, 0.883 vs. 0.897, P=0.126; S3, 0.832 vs. 0.834, P=0.799). Conclusion UGAP had high diagnostic performance in diagnosing hepatic steatosis, regardless of the number of repetitions (six repetitions vs. 12 repetitions), with maintained reliability. Therefore, six UGAP measurements seem sufficient for evaluating hepatic steatosis using UGAP.

Purpose: To investigate the characteristics and treatment results of patients aged ≥ 85 years who were diagnosed with treatment-naïve neovascular age-related macular degeneration (nAMD). Methods: The medical records of patients diagnosed with treatment-naïve nAMD who were ≥ 85 years old at the time of diagnosis with at least 12 months follow-up were retrospectively reviewed. The number of intravitreal injections of anti-vascular endothelial growth factor (VEGF) and agents used during the entire period were investigated. Best-corrected visual acuity and optical coherence tomography results before and after treatment were analyzed. Visual acuity of the fellow eye was also collected. Results: A total of 40 eyes of 40 patients with mean age of 87.5 ± 2.4 were included in the study. The mean logarithm of the minimal angle of resolution visual acuity was 0.85 ± 0.57, and the mean of the fellow eye was 0.93 ± 0.99. Compared to before the treatment, there was no significant difference after intravitreal injection in terms of visual acuity. Central retinal thickness showed significant reduction at all time points after treatment. Conclusions In patients aged ≥ 85 years at the time of diagnosis, intravitreal injections of anti-VEGF prevented deterioration of visual acuity and showed successful anatomical outcomes. Especially, many had poor visual acuity in the fellow eye, suggesting the importance of maintaining visual acuity. Therefore, active treatment is necessary in the elderly.