Background: Citric acid (CA) and sodium hypochlorite (NaOCl) have been used to disinfect animals to protect them against avian influenza and foot-and-mouth disease. Objectives: We performed a good laboratory practice (GLP)-compliant animal toxicity study to assess the acute toxic effects of CA and NaOCl aerosol exposure in Sprague-Dawley rats. Methods: Groups of five rats per sex were exposed for 4 h to four concentrations of the two chemicals, i.e., 0.00, 0.22, 0.67, and 2.00 mg/L, using a nose-only exposure. After a single exposure to the chemicals, clinical signs, body weight, and mortality was observed during the observation period. On day 15, an autopsy, and then gross findings, and histopathological analysis were performed. Results: After exposure to CA and NaOCl, body weight loss was observed but recovered.Two males died in the CA 2.00 mg/L group and, two males and one female died in the 2.00 mg/L NaOCl group. In the gross findings and histopathological analysis, discoloration of the lungs was observed in the CA exposed group and inflammatory lesions with discoloration of the lungs were observed in the NaOCl exposed group. These results suggest that the lethal concentration 50 (LC50) of CA is 1.73390 mg/L for males and > 1.70 mg/L for females. For NaOCl, the LC50 was 2.22222 mg/L for males and 2.39456 mg/L for females. Conclusions The Globally Harmonized System is category 4 for both CA and NaOCl. In this study, the LC50 results were obtained through a GLP-based acute inhalation toxicity assessment. These results provide useful data to reset safety standards for CA and NaOCl use.

Objectives: . Numerous minimally invasive thyroidectomy techniques have been developed and are actively utilized in hospitals around the globe. Herein, we describe a recently developed minimally invasive thyroidectomy technique that employs the da Vinci SP, and we present the preliminary clinical outcomes of single-port robotic areolar thyroidectomy (SPRA). Methods: . A 3-cm semi-circular incision on the right areola and a small 8-mm incision on the left areola were created. Using hydro-dissection and an advanced bipolar device, a subcutaneous skin flap was created, extending from the areola to the thyroid cartilage. The da Vinci SP was then inserted through the incision in the right areola. Between December 2022 and March 2023, 21 SPRA procedures were conducted. Patients’ medical records and surgical videos were subsequently reviewed. Results: . Lobectomy was performed in 17 patients, isthmectomy in 2 patients, and total thyroidectomy in 2 patients. The mean flap time was 14.9±4.2 minutes and the console time was 62.4±17.1 minutes. The mean tumor size was 0.89± 0.65 cm and the number of retrieved lymph nodes was 3.94±3.98 (range, 0–12). There were no observed instances of vocal cord palsy or hypoparathyroidism. Conclusion . We successfully developed and performed the novel SPRA for the first time worldwide. Unlike other robotic surgery methods, SPRA is less invasive and leaves no visible scars. This technique employs a sophisticated single-port robotic device. However, to assess the efficacy of this method, we need to analyze more cases and conduct comparative studies in the near future.

. Ankylosing spondylitis (AS) is a chronic inflammatory disease with obvious male preponderance. Males show more severe radiographic manifestations compared with females. This study aimed to evaluate the effects of sex and estrogen on the radiographic progression of AS. Methods. A total of 101 patients with AS were included in this study. All of the radiographs were scored using the modified Stoke AS Spine Score (mSASSS). Serum levels of 17β-estradiol (E2), dickkopf-1 (Dkk1), and leptin were detected by enzyme-linked immunosorbent assay. The generalized estimating equations model was used to evaluate factors associated with spinal radiographic progression. Results. The mean age at disease onset was 27.3±10.7 years, and 16 patients (15.8%) were female. In the multivariable analysis, body mass index (β-coefficient=0.12; β=0.047) and levels of Dkk1 (β-coefficient=−0.11; β＜0.001), and female (β-coefficient=−1.40; β=0.001) were associated with radiographic progression. Among male patients with AS, baseline C-reactive protein (β=0.11; β=0.005) and mSASSS (β=0.21; p=0.030) were also associated with radiographic progression. E2 and leptin levels were not significantly related to the radiographic progression. Conclusion. Although female patients were associated with less radiographic progression in AS, there was no significant relationship between serum estrogen level and radiographic progression. Results of current study suggests that genetic factors or other environmental factors associated with female may influence radiographic progression in patients with AS.

Background: Tuberculous meningitis (TBM) is the most severe form of tuberculosis, but differentiating between the diagnosis of TBM and viral meningitis (VM) is difficult. Thus, we have developed machine-learning modules for differentiating TBM from VM.Material and Methods: For the training data, confirmed or probable TBM and confirmed VM cases were retrospectively collected from five teaching hospitals in Korea between January 2000 - July 2018. Various machine-learning algorithms were used for training. The machinelearning algorithms were tested by the leave-one-out cross-validation. Four residents and two infectious disease specialists were tested using the summarized medical information. Results: The training study comprised data from 60 patients with confirmed or probable TBM and 143 patients with confirmed VM. Older age, longer symptom duration before the visit, lower serum sodium, lower cerebrospinal fluid (CSF) glucose, higher CSF protein, and CSF adenosine deaminase were found in the TBM patients. Among the various machinelearning algorithms, the area under the curve (AUC) of the receiver operating characteristics of artificial neural network (ANN) with ImperativeImputer for matrix completion (0.85; 95% confidence interval 0.79 - 0.89) was found to be the highest. The AUC of the ANN model was statistically higher than those of all the residents (range 0.67 - 0.72, P <0.001) and an infectious disease specialist (AUC 0.76; P = 0.03). Conclusion The machine-learning techniques may play a role in differentiating between TBM and VM. Specifically, the ANN model seems to have better diagnostic performance than the non-expert clinician.

Background: Tuberculous meningitis (TBM) is the most severe form of tuberculosis, but differentiating between the diagnosis of TBM and viral meningitis (VM) is difficult. Thus, we have developed machine-learning modules for differentiating TBM from VM.Material and Methods: For the training data, confirmed or probable TBM and confirmed VM cases were retrospectively collected from five teaching hospitals in Korea between January 2000 - July 2018. Various machine-learning algorithms were used for training. The machinelearning algorithms were tested by the leave-one-out cross-validation. Four residents and two infectious disease specialists were tested using the summarized medical information. Results: The training study comprised data from 60 patients with confirmed or probable TBM and 143 patients with confirmed VM. Older age, longer symptom duration before the visit, lower serum sodium, lower cerebrospinal fluid (CSF) glucose, higher CSF protein, and CSF adenosine deaminase were found in the TBM patients. Among the various machinelearning algorithms, the area under the curve (AUC) of the receiver operating characteristics of artificial neural network (ANN) with ImperativeImputer for matrix completion (0.85; 95% confidence interval 0.79 - 0.89) was found to be the highest. The AUC of the ANN model was statistically higher than those of all the residents (range 0.67 - 0.72, P <0.001) and an infectious disease specialist (AUC 0.76; P = 0.03). Conclusion The machine-learning techniques may play a role in differentiating between TBM and VM. Specifically, the ANN model seems to have better diagnostic performance than the non-expert clinician.

Background: There is limited information describing the presenting characteristics and dynamic clinical changes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection diagnosed in the early phase of illness. This study is a case series of patients with coronavirus disease 2019 (COVID-19) admitted to 11 hospitals in Korea. Methods: Patients with confirmed SARS-CoV-2 infection by positive polymerase chain reaction (PCR) testing of respiratory specimens by active surveillance that were finally discharged between February 20 and April 30, 2020 were included. Patients were classified into mild and non-mild groups on initial admission according to oxygen demand and Sequential Organ Failure Assessment score, and the mild group was followed up and subgrouped into non-aggravation and aggravation groups. Results: A total of 161 patients with SARS-CoV2 infection were enrolled. Among the mild group of 136 patients, 11.7% of patients experienced clinical aggravation during hospitalization, but there was no initial clinical parameter on admission predicting their aggravation. Fever (odds ratio [OR], 4.56), thrombocytopenia (OR, 12.87), fever (OR, 27.22) and lactate dehydrogenase (LDH) > 300 U/L (OR, 18.35), and CRP > 1 mg/dL (OR, 11.31) significantly indicated aggravation in the 1st, 2nd, 3rd, and 4th 5-day periods, respectively.PCR positivity lasted for a median of 22 days and 32 days after the onset of illness in the nonaggravation and aggravation groups, respectively. Conclusion Old age was associated with early severe presentation. Clinical aggravation among asymptomatic or mild patients could not be predicted initially but was heralded by fever and several laboratory markers during the clinical course.

Purpose: Data on the distribution and impact of panel reactive antibodies (PRA) and donor specific antibodies (DSA) before lung transplantation in Asia, especially multi-center-based data, are limited. This study evaluated the prevalence of and effects of PRA and DSA levels before lung transplantations on outcomes in Korean patients using nationwide multicenter registry data. Materials and Methods: This study included 103 patients who received a lung transplant at five tertiary hospitals in South Korea between March 2015 and December 2017. Mortality, primary graft dysfunction (PGD), and bronchiolitis obliterans syndrome (BOS) were evaluated. Results: Sixteen patients had class I and/or class II PRAs exceeding 50%. Ten patients (9.7%) had DSAs with a mean fluorescence intensity (MFI) higher than 1000, six of whom had antibodies with a high MFI (≥2000). DSAs with high MFIs were more frequently observed in patients with high-grade PGD (≥2) than in those with no or low-grade (≤1) PGD. In the 47 patients who survived for longer than 9 months and were evaluated for BOS after the transplant, BOS was not related to DSA or PRA levels. One-year mortality was more strongly related to PRA class I exceeding 50% than that under 50% (0% vs. 16.7%, p=0.007). Conclusion Preoperative DSAs and PRAs are related to worse outcomes after lung transplantation. DSAs and PRAs should be considered when selecting lung transplant recipients, and recipients who have preoperative DSAs with high MFI values and high PRA levels should be monitored closely after lung transplantation.

Objectives: The Korea Centers for Disease Control and Prevention has published “A Guideline for Unknown Disease Outbreaks (UDO).” The aim of this report was to introduce tabletop exercises (TTX) to prepare for UDO in the future. Methods: The UDO Laboratory Analyses Task Force in Korea Centers for Disease Control and Prevention in April 2018, assigned unknown diseases into 5 syndromes, designed an algorithm for diagnosis, and made a panel list for diagnosis by exclusion. Using the guidelines and laboratory analyses for UDO, TTX were introduced. Results: Since September 9th , 2018, the UDO Laboratory Analyses Task Force has been preparing TTX based on a scenario of an outbreak caused by a novel coronavirus. In December 2019, through TTX, individual missions, epidemiological investigations, sample treatments, diagnosis by exclusions, and next generation sequencing analysis were discussed, and a novel coronavirus was identified as the causal pathogen. Conclusion Guideline and laboratory analyses for UDO successfully applied in TTX. Conclusions drawn from TTX could be applied effectively in the analyses for the initial response to COVID-19, an ongoing epidemic of 2019 - 2020. Therefore, TTX should continuously be conducted for the response and preparation against UDO.

PURPOSE: Nutritional therapy (NT), such as enteral nutrition (EN) or parenteral nutrition (PN), is essential for the malnourished patients. Although the complications related to NT has been well described, multicenter data on symptoms in the patients with receiving NT during hospitalization are still lacking. METHODS: Nutrition support team (NST) consultations, on which NT-related complications were described, were collected retrospectively for one year. The inclusion criteria were patients who were (1) older than 18 years, (2) hospitalized, and (3) receiving EN or PN at the time of NST consultation. The patients' demographics (age, sex, body mass index [BMI]), type of NT and type of complication were collected. To compare the severity of each complication, the intensive care unit (ICU) admission, hospital stay, and type of discharge were also collected. RESULTS: A total of 14,600 NT-related complications were collected from 13,418 cases from 27 hospitals in Korea. The mean age and BMI were 65.4 years and 21.8 kg/m2. The complications according to the type of NT, calorie deficiency (32.4%, n=1,229) and diarrhea (21.6%, n=820) were most common in EN. Similarly, calorie deficiency (56.8%, n=4,030) and GI problem except for diarrhea (8.6%, n=611) were most common in PN. Regarding the clinical outcomes, 18.7% (n=2,158) finally expired, 58.1% (n=7,027) were admitted to ICU, and the mean hospital days after NT-related complication were 31.3 days. Volume overload (odds ratio [OR]=3.48) and renal abnormality (OR=2.50) were closely associated with hospital death; hyperammonemia (OR=3.09) and renal abnormality (OR=2.77) were associated with ICU admission; “micronutrient and vitamin deficiency” (geometric mean [GM]=2.23) and volume overload (GM=1.61) were associated with a longer hospital stay. CONCLUSION: NT may induce or be associated with several complications, and some of them may seriously affect the patient's outcome. NST personnel in each hospital should be aware of each problem during nutritional support.
Adult ; Body Mass Index ; Demography ; Diarrhea ; Enteral Nutrition ; Hospitalization ; Humans ; Hyperammonemia ; Intensive Care Units ; Korea ; Length of Stay ; Multicenter Studies as Topic ; Nutrition Therapy ; Nutritional Support ; Parenteral Nutrition ; Referral and Consultation ; Retrospective Studies ; Vitamins

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) infection is associated with high mortality. One of the strategies to reduce the mortality in patients with CRAB infections is to use intravenous colistin early but the effect of this strategy has not been proven. Therefore, we investigated the association of early colistin therapy with 28-day mortality in patients with CRAB bacteremia. METHODS: This retrospective multicenter propensity score-matching analysis was conducted in the Korea by reviewing the medical records of adult patients with CRAB bacteremia between January 2012 and March 2015. Early colistin therapy was defined as intravenous colistin administration for > 48 hours within five days after the blood culture collection. To identify the risk factors associated with the 28-day mortality in CRAB bacteremia, the clinical variables of the surviving patients were compared to those of the deceased patients. RESULTS: Of 303 enrolled patients, seventy-six (25.1%) patients received early colistin therapy. The 28-day mortality was 61.4% (186/303). Fatal or rapidly-fatal McCabe classifications, intensive care unit admission, Sequential Organ Failure Assessment scores ≥ 8, vasopressor use, and acute kidney injury were statistically independent poor prognostic factors. Catheter-related infection and early colistin therapy (adjusted odds ratio [aOR], 0.45; 95% confidence interval [CI], 0.21–0.94) were independent favorable prognostic factors associated with 28-day mortality in patients with CRAB bacteremia. Early colistin therapy was still significantly associated with lower 28-day mortality in the propensity score-matching analysis (aOR, 0.31; 95% CI, 0.11–0.88). CONCLUSION: This study suggests that early colistin therapy might help reduce the mortality of patients with CRAB bacteremia.
Acinetobacter ; Acinetobacter baumannii ; Acute Kidney Injury ; Adult ; Bacteremia ; Catheter-Related Infections ; Classification ; Colistin ; Humans ; Intensive Care Units ; Korea ; Medical Records ; Mortality ; Odds Ratio ; Organ Dysfunction Scores ; Retrospective Studies ; Risk Factors