Purpose: Due to chronic toxicity, tacrolimus-sparing is an important issue in kidney transplant recipients (KTRs). Several studies have shown that bisphosphonate use is associated with favorable graft outcomes in KTRs. We investigated whether the association between tacrolimus trough levels (TTLs) and graft outcomes differed according to bisphosphonate use in KTRs. Materials and Methods: We conducted a retrospective study encompassing 1441 KTRs who were administered tacrolimus-based immunosuppressants. The primary exposure was a time-dependent cross-product of TTLs (low TTLs vs. normal-high TTLs with a reference of 6 ng/mL) and bisphosphonate use. Two primary outcomes were evaluated: overall graft loss (death or conversion to kidney replacement) and an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m 2 . Results: During the median follow-up of 6.1 (3.4–9.7) years, overall graft loss occurred in 157 (10.9%) patients. Cox regression revealed that normal-high TTLs without bisphosphonate use were associated with a reduced risk of overall graft loss [adjusted hazard ratio (aHR), 0.65; 95% confidence interval (CI), 0.45–0.95] compared to low TTLs without bisphosphonate use. The use of bisphosphonate in conjunction with normal-high TTLs correlated with an even lower risk of overall graft loss (aHR, 0.25; 95% CI, 0.08–0.80) compared with low TTLs without bisphosphonate use. In patients with low TTLs, bisphosphonate use was associated with a reduced risk of overall graft loss compared with non-use (aHR, 0.20; 95% CI, 0.09–0.43). Similar trends were observed in the eGFR outcome. Conclusion The use of bisphosphonate was associated with favorable graft outcomes, even with low TTLs. Incorporating bisphosphonate into a conventional immunosuppressant regimen may potentially reduce tacrolimus requirement.

Purpose: Stem cell transplantation (SCT) has historically played a major role in the long-term remission of mantle cell lymphoma (MCL), an incurable hematological malignancy. Using data from the Korean Society of Bone and Marrow Transplantation registry, we retrospectively analyzed the role of autologous (auto) and allogeneic (allo) SCT in longterm MCL survival. Methods: This study analyzed data from 188 patients (age ≥ 19 years at the time of transplantation) who underwent a transplant for MCL from 2011 to 2020. Progression-free survival (PFS) was defined as the time from transplantation to disease progression, relapse, or death from any cause. Overall survival (OS) was defined as the time from transplan‑ tation to death from any cause or the last follow-up. Results: In total, 109 patients underwent consolidative SCT after first-line chemotherapy. The 3-year PFS and OS rates were 65.4% and 78.5%, respectively, in the auto-SCT group, and 66.7% and 71.4%, respectively, in the allo-SCT group. The PFS and OS did not differ significantly between the auto- and allo-SCT groups. As part of salvage treatment, 52 patients with relapsed or refractory disease underwent auto- or allo-SCT. Patients who underwent auto-SCT with complete remis‑ sion/partial remission status reported better outcomes. In patients with refractory status, allogeneic transplantation using human leukocyte antigen (HLA) fully matched donors was a significantly favorable factor for PFS and OS. Conclusion The long-term survival of patients who underwent consolidative transplantation was similar to that reported in previous studies. Auto-SCT may be beneficial in patients who respond to salvage therapy, whereas allo-SCT with HLA-matched donors may be an alternative for patients with refractory disease. 

Objective: The Scales for Outcomes in Parkinson’s Disease–Cognition (SCOPA-Cog) was developed to assess cognition in patients with Parkinson’s disease (PD). In this study, we aimed to evaluate the validity and reliability of the Korean version of the SCOPACog (K-SCOPA-Cog). Methods: We enrolled 129 PD patients with movement disorders from 31 clinics in South Korea. The original version of the SCOPA-Cog was translated into Korean using the translation-retranslation method. The test–retest method with an intraclass correlation coefficient (ICC) and Cronbach’s alpha coefficient were used to assess reliability. Spearman’s rank correlation analysis with the Montreal Cognitive Assessment-Korean version (MOCA-K) and the Korean Mini-Mental State Examination (K-MMSE) were used to assess concurrent validity. Results: The Cronbach’s alpha coefficient was 0.797, and the ICC was 0.887. Spearman’s rank correlation analysis revealed a significant correlation with the K-MMSE and MOCA-K scores (r = 0.546 and r = 0.683, respectively). Conclusion Our results demonstrate that the K-SCOPA-Cog has good reliability and validity.

Whether advanced age is associated with poor outcomes of elderly patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) is controversial. This study aimed to evaluate age effect and predictors for mortality in elderly AKI patients undergoing CRRT. Methods: Data of 480 elderly AKI patients who underwent CRRT were retrospectively analyzed. Subjects were stratified into two groups according to age: younger-old (age, 65–74 years; n = 205) and older-old (age, ≥75 years; n = 275). Predictors for 28-day and 90-day mortality and age effects were analyzed using multivariable Cox regression analysis and propensity score matching. Results: Urine output at the start of CRRT (adjusted hazard ratio [aHR], 0.99; 95% confidence interval [CI], 0.99–1.00; p = 0.04), operation (aHR, 0.53; 95% CI, 0.30–0.93; p = 0.03), and use of an intra-aortic balloon pump (aHR, 3.60; 95% CI, 1.18–10.96; p = 0.02) were predictors for 28-day mortality. Ischemic heart disease (aHR, 1.74; 95% CI, 1.02–2.98; p = 0.04) and use of a ventilator (aHR, 0.56; 95% CI, 0.36–0.89; p = 0.01) were predictors for 90-day mortality. The older-old group did not exhibit a higher risk for 28- day or 90-day mortality than the younger-old group in multivariable or propensity score-matched models. Conclusion: Advanced age was not a risk factor for mortality among elderly AKI patients undergoing CRRT, suggesting that advanced age should not be considered for therapeutic decisions in critically ill elderly patients with AKI requiring CRRT.

Purpose: Diffuse large B-cell lymphoma (DLBCL) is the most common hematologic malignancy worldwide. Although substantial improvement has been achieved by the frontline rituximab-based chemoimmunotherapy, up to 40%-50% of patients will eventually have relapsed or refractory disease, whose prognosis is extremely dismal. Materials and Methods: We have carried out two prospective cohort studies that include over 1,500 DLBCL patients treated with rituximab plus CHOP (#NCT01202448 and #NCT02474550). In the current report, we describe the outcomes of refractory DLBCL patients. Patients were defined to have refractory DLBCL if they met one of the followings, not achieving at least partial response after 4 or more cycles of R-CHOP; not achieving at least partial response after 2 or more cycles of salvage therapy; progressive disease within 12 months after autologous stem cell transplantation. Results: Among 1,581 patients, a total of 260 patients met the criteria for the refractory disease after a median time to progression of 9.1 months. The objective response rate of salvage treatment was 26.4%, and the complete response rate was 9.6%. The median overall survival (OS) was 7.5 months (95% confidence interval, 6.4 to 8.6), and the 2-year survival rate was 22.1%±2.8%. The median OS for each refractory category was not significantly different (p=0.529). Conclusion In line with the previous studies, the outcomes of refractory DLBCL patients were extremely poor, which necessitates novel approaches for this population.

Pancreatic metastasis from papillary thyroid cancer (PTC) is extremely rare; only 18 cases have been reported in the literature. However, several reviews have highlighted similar characteristics between metastatic and primary pancreatic tumors. The patient was a 51-year-old male with a history of total thyroidectomy, modified radical neck dissection, and radioactive iodine ablation for PTC in 2014. Nodules suspected of metastasis were found in both lungs on chest computed tomography (CT). However, after 6 months, a follow-up chest CT showed no increase in size; thus, a follow-up observation was planned. Six years after his initial diagnosis, abdominal CT and pancreas magnetic resonance imaging revealed a 4.7 cm cystic mass with a 2.5 cm enhancing mural nodule in the pancreas tail. We diagnosed the pancreatic lesion as either metastatic cancer or primary pancreas cancer. The patient underwent distal pancreato-splenectomy. After surgery, the pathological report revealed that the mass was metastatic PTC. Pancreatic metastasis from PTC indicates an advanced tumor stage and poor prognosis. However, pancreatectomy can increase the survival rate when the lesion is completely resectable. Therefore, surgical resection should be considered as a treatment for pancreatic metastasis from PTC.

Objective: To develop and evaluate a deep learning-based artificial intelligence (AI) model for detecting skull fractures on plain radiographs in children. Materials and Methods: This retrospective multi-center study consisted of a development dataset acquired from two hospitals (n = 149 and 264) and an external test set (n = 95) from a third hospital. Datasets included children with head trauma who underwent both skull radiography and cranial computed tomography (CT). The development dataset was split into training, tuning, and internal test sets in a ratio of 7:1:2. The reference standard for skull fracture was cranial CT. Two radiology residents, a pediatric radiologist, and two emergency physicians participated in a two-session observer study on an external test set with and without AI assistance. We obtained the area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity along with their 95% confidence intervals (CIs). Results: The AI model showed an AUROC of 0.922 (95% CI, 0.842–0.969) in the internal test set and 0.870 (95% CI, 0.785–0.930) in the external test set. The model had a sensitivity of 81.1% (95% CI, 64.8%–92.0%) and specificity of 91.3% (95% CI, 79.2%–97.6%) for the internal test set and 78.9% (95% CI, 54.4%–93.9%) and 88.2% (95% CI, 78.7%– 94.4%), respectively, for the external test set. With the model’s assistance, significant AUROC improvement was observed in radiology residents (pooled results) and emergency physicians (pooled results) with the difference from reading without AI assistance of 0.094 (95% CI, 0.020–0.168; p = 0.012) and 0.069 (95% CI, 0.002–0.136; p = 0.043), respectively, but not in the pediatric radiologist with the difference of 0.008 (95% CI, -0.074–0.090; p = 0.850). Conclusion A deep learning-based AI model improved the performance of inexperienced radiologists and emergency physicians in diagnosing pediatric skull fractures on plain radiographs.

Background: To evaluate workload in emergency rooms (ERs) among clinical specialties including neurology and investigate characteristics of neurological consultations in ER. Methods: A nationwide survey was conducted to evaluate the number of specialists, resident physicians/surgeons, and emergency consultations of each clinical specialty in Korean tertiary referral hospitals from 2018 to 2019. Characteristics of neurological emergency consultations during the same period were investigated in one of the hospitals that participated. Results: A total of 23 hospitals were included. Four irrelevant clinical specialties were excluded. The number of neurology specialists and resident physicians were 12.5/hospital (4.1% of all specialists) and 6.4/hospital (3.4% of all resident physicians/surgeons), respectively, while the mean numbers of specialists and resident physicians or surgeons per clinical specialty were 13.7/hospital and 8.6/hospital, respectively. Neurological consultations accounted for 11.0% of all ER consultations for severe patients (Korean Triage and Acuity Scale level 1-3). Annual ER consultations for severe patients per neurology specialist was 274.1, which was only second to pediatrics (290.0). Annual ER consultations for severe patients per resident physician was 406.6 which was 1.6 times higher than the second highest (internal medicine, 247.0). Frequent conditions for neurological ER consultation were dizziness (24.8%), motor weakness (23.9%), headache (10.6%), dysarthria (9.9%), and seizures (7.7%). Frequent primary diagnoses were cerebrovascular diseases (29.0%) and episodic and paroxysmal disorders (24.9%). Conclusions Workloads of neurology specialists for ER consultation were significantly heavy, and the workload of neurology resident physicians was the heaviest among all specialties. This should be considered in health care policies.

Purpose: Febrile neutropenia (FN) can cause suboptimal treatment and treatment-related mortality (TRM) in diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP). Materials and methods: We conducted a prospective cohort study to evaluate the effectiveness of pegfilgrastim prophylaxis in DLBCL patients receiving R-CHOP, and we compared them with the PROCESS cohort (n=485). Results: Since January 2015, 986 patients with DLBCL were enrolled. Pegfilgrastim was administered at least once in 930 patients (94.3%), covering 90.3% of all cycles. FN developed in 137 patients (13.9%) in this cohort (23.7% in the PROCESS cohort, p<0.001), and 4.2% of all cycles (10.2% in the PROCESS cohort, p<0.001). Dose delay was less common (≥3 days: 18.1% vs. 23.7%, p=0.015; ≥5 days: 12.0% vs. 18.3%, p=0.023) in this cohort than in the PROCESS cohort. The incidence of TRM (3.2% vs. 5.6%, p=0.047) and infection-related death (1.8% vs. 4.5%, p=0.004) was lower in this cohort than in the PROCESS cohort. The 4-year overall survival (OS) and progression-free survival (PFS) rates of the two cohorts were not different (OS: 73.0% vs. 71.9%, p=0.545; PFS: 69.5% vs. 68.8%, p=0.616). However, in patients aged ≥75 years, the 4-year OS and PFS rates were higher in this cohort than in the PROCESS cohort (OS: 49.6% vs. 33.7%, p=0.032; PFS: 44.2% vs. 30.3% p=0.047). Conclusion Pegfilgrastim prophylaxis is effective in the prevention of FN and infection-related death in DLBCL patients receiving R-CHOP, and it also improves OS in patients aged ≥75 years.

Background: Because Korea is the fastest aging country, the stroke incidence is increasing rapidly. We investigate the trend of the number of patients with acute stroke in recent years and estimate the burden of the neurologist to treat the acute stroke patient visited the emergency department. Methods: We requested a questionnaire survey to all teaching hospitals on the number of hospital beds, the number of stroke patients who visited the emergency department, the number of stroke patients in charge of the neurologist, and the number of days on duty of residents from 2016 to 2019. Results: Of 69 teaching hospitals, 41 hospitals answered the survey. The average hospital beds per hospital were increased annually from 909 to 916. The average patients who visited the emergency department with stroke and were in charged to neurologists were rapidly increased from 799 to 867 per hospital. In particular, the number of patients with hyperacute cerebral infarction requiring the thrombolytic administration or mechanical thrombectomy were rapidly increased from 105 to 131. On the other hand, the average number of residents per hospital was decreased from 5.1 to 4.8. Therefore, the days on duty per resident were increased from 74 to 77. Conclusions The number of acute stroke patients, especially, hyperacute stroke required the rapid cooperation and high labor were increasing rapidly in recent years. However, because the number of residents were decreased, the burden was increasing. To improve the quality of acute stroke treatment, it is necessary to increase the number of residents.