Cumulative sum analysis of the learning curve for retrograde intrarenal stone surgery in newbie surgeons.

INTRODUCTION: This study investigated the learning curve of retrograde intrarenal surgery (RIRS) in patients with medium-sized stones using cumulative sum analysis (CUSUM) to evaluate the competence and proficiency of three new surgeons during their first RIRS procedures. MATERIALS AND METHODS: We conducted a retrospective review of 227 patients from 2019 to 2022 at a single institution. The patients were divided into four groups based on the operating surgeon: tutor surgeon (85 patients), newbie surgeon A (21 patients), newbie surgeon B (85 patients), and newbie surgeon C (36 patients). Patients had one or multiple stones with the largest stone diameter fell within the range of 10-30 mm. Fragmentation efficacy was calculated as "removed stone volume (mm3) divided by operative time (minutes)." CUSUM analysis monitored changes in fragmentation efficacy and validated surgical outcomes. RESULTS: No statistically significant differences were observed in the total stone volume, maximum stone size, or total operation time between the three newbie surgeons and the tutor surgeon. The mean fragmentation efficacy value was comparable among the newbie surgeons, but significantly different from that of the tutor surgeon. The minimum acceptable fragmentation efficacy level was set at 25.12 mL/min, based on the tutor's average value. The CUSUM curves for the three surgeons initially remained relatively flat until Cases 12-15, after which they increased and eventually plateaued. Stone-free rates and postoperative complications did not differ significantly among the surgeons. CONCLUSION: Learning curve analysis for the three newbie surgeons indicated that approximately 12-15 cases were required to reach a plateau.

Prominent transcriptomic changes in Mycobacterium intracellulare under acidic and oxidative stress.

BACKGROUND: Mycobacterium avium complex (MAC), including Mycobacterium intracellulare is a member of slow-growing mycobacteria and contributes to a substantial proportion of nontuberculous mycobacterial lung disease in humans affecting immunocompromised and elderly populations. Adaptation of pathogens in hostile environments is crucial in establishing infection and persistence within the host. However, the sophisticated cellular and molecular mechanisms of stress response in M. intracellulare still need to be fully explored. We aimed to elucidate the transcriptional response of M. intracellulare under acidic and oxidative stress conditions. RESULTS: At the transcriptome level, 80 genes were shown [FC] ≥ 2.0 and p < 0.05 under oxidative stress with 10 mM hydrogen peroxide. Specifically, 77 genes were upregulated, while 3 genes were downregulated. In functional analysis, oxidative stress conditions activate DNA replication, nucleotide excision repair, mismatch repair, homologous recombination, and tuberculosis pathways. Additionally, our results demonstrate that DNA replication and repair system genes, such as dnaB, dinG, urvB, uvrD2, and recA, are indispensable for resistance to oxidative stress. On the contrary, 878 genes were shown [FC] ≥ 2.0 and p < 0.05 under acidic stress with pH 4.5. Among these genes, 339 were upregulated, while 539 were downregulated. Functional analysis highlighted nitrogen and sulfur metabolism pathways as the primary responses to acidic stress. Our findings provide evidence of the critical role played by nitrogen and sulfur metabolism genes in the response to acidic stress, including narGHIJ, nirBD, narU, narK3, cysND, cysC, cysH, ferredoxin 1 and 2, and formate dehydrogenase. CONCLUSION: Our results suggest the activation of several pathways potentially critical for the survival of M. intracellulare under a hostile microenvironment within the host. This study indicates the importance of stress responses in M. intracellulare infection and identifies promising therapeutic targets.

Bigger problems from smaller colonies: emergence of antibiotic-tolerant small colony variants of Mycobacterium avium complex in MAC-pulmonary disease patients.

BACKGROUND: Mycobacterium avium complex (MAC) is a group of slow-growing mycobacteria that includes Mycobacterium avium and Mycobacterium intracellulare. MAC pulmonary disease (MAC-PD) poses a threat to immunocompromised individuals and those with structural pulmonary diseases worldwide. The standard treatment regimen for MAC-PD includes a macrolide in combination with rifampicin and ethambutol. However, the treatment failure and disease recurrence rates after successful treatment remain high. RESULTS: In the present study, we investigated the unique characteristics of small colony variants (SCVs) isolated from patients with MAC-PD. Furthermore, revertant (RVT) phenotype, emerged from the SCVs after prolonged incubation on 7H10 agar. We observed that SCVs exhibited slower growth rates than wild-type (WT) strains but had higher minimum inhibitory concentrations (MICs) against multiple antibiotics. However, some antibiotics showed low MICs for the WT, SCVs, and RVT phenotypes. Additionally, the genotypes were identical among SCVs, WT, and RVT. Based on the MIC data, we conducted time-kill kinetic experiments using various antibiotic combinations. The response to antibiotics varied among the phenotypes, with RVT being the most susceptible, WT showing intermediate susceptibility, and SCVs displaying the lowest susceptibility. CONCLUSIONS: In conclusion, the emergence of the SCVs phenotype represents a survival strategy adopted by MAC to adapt to hostile environments and persist during infection within the host. Additionally, combining the current drugs in the treatment regimen with additional drugs that promote the conversion of SCVs to RVT may offer a promising strategy to improve the clinical outcomes of patients with refractory MAC-PD.

Lack of association between Inhaled Corticosteroid use based on the Exhaled Nitric Oxide and Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

Background: Fractional exhaled nitric oxide (FeNO) is known to useful biomarker for detecting eosinophilic airway inflammation. However, there is a lack of evidence regarding the role of FeNO in chronic obstructive pulmonary disease (COPD). We aimed to assess whether elevated FeNO and its impact on treatment change into an inhaled corticosteroid (ICS)-containing regimen and association with acute exacerbation (AE) in patients with COPD. Methods: We retrospectively analyzed 107 COPD patients without history of asthma from March 2016 to December 2019. The patients whose FeNO value was more than 50 parts per billion [ppb] were defined into the high FeNO group. Multivariable analysis with logistic regression was used to identify factors associated with AE in COPD. Results: The median FeNO value was 32 (Interquartile range [IQR], 19-45) ppb, and 34 (20.0%) patients were classified as high FeNO group (median 74ppb). In the high FeNO group, changes in inhaler treatment into an ICS-containing regimen occurred in 23 of 34 patients after the measurement of FeNO. In multivariate analysis, high FeNO was not a contributing factor for AE, but only the high blood eosinophil count (≥ 300 cells/µL) was associated with AE (adjusted odds ratio, 2.63; 95% confidence interval, 1.01-6.91; p = 0.049). Conclusions: High FeNO value had a significant impact on the prescription of ICSs in COPD patients, but it did not show a significant association with AE either on its own or with changes in treatment.

Risk Factors for the Mortality of Patients With Coronavirus Disease 2019 Requiring Extracorporeal Membrane Oxygenation in a Non-Centralized Setting: A Nationwide Study.

BACKGROUND: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. METHODS: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan-Meier (KM) method. RESULTS: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010-1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312-7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). CONCLUSION: Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.

Is There a Difference in the Incidence of Depression between Radiation and Surgical Treatments in Patients with Prostate Cancer?

PURPOSE: Patients with cancer have a high risk of depression. However, a few studies have assessed differences in the incidence of depression among patients with prostate cancer (PC) based on whether they received radiotherapy (RTx) or surgical treatment. MATERIALS AND METHODS: We analyzed data from the National Health Insurance Sharing Service database regarding the entire Korean adult population with PC (n=210,924) between 2007 and 2017. The adjusted hazard ratios (HRs) of depression associated with treatment were estimated using propensity score-matched Cox proportional hazards models and Kaplan-Meier survival analyses. RESULTS: Our final cohort comprised 9,456 patients with PC; of which, 8,050 men underwent surgery. During a mean follow-up duration of 7.1 years, 503 (5.3%) patients were newly diagnosed with depression. A significant difference in the incidence of depression was noted between the RTx and surgery groups (RTx vs. surgery: 5.55% vs. 5.28%; p=0.011) in the unmatched cohort. In the matched cohort, older age (≥70 years, HR: 1.596, p<0.001) and poor Charlson comorbidity index scores (HR: 1.232, p=0.039) were correlated with the risk of depression. In addition, the adjusted HR for depression in the surgery group was 0.843 (p=0.221) compared with that in the RTx group. Kaplan-Meier analyses revealed that no significant difference in the cumulative probability of persistent depression was detected between the RTx and surgery groups in matched cohort (p=0.3386). CONCLUSIONS: In this nationwide population-based study, no significant differences in the risk of depression were observed between the surgical and RTx groups.

Epidemiology of mumps, mumps complications, and mumps orchitis in Korea using the National Health Insurance Service database.

PURPOSE: To analyze the presentation of mumps and mumps orchitis using the National Health Insurance Service Database (NHISD). MATERIALS AND METHODS: Using information from the NHISD representing all cases of mumps in Korea, data regarding mumps orchitis were analyzed. The International Classification of Diseases, Tenth Revision, and Clinical Modification codes were used for diagnosis. The incidence estimates of the number of mumps cases were analyzed using the Statistical Analysis System (SAS) software. RESULTS: Based on the NHISD, 199,186 people were diagnosed with mumps, and males accounted for 62.3% cases. Teen males accounted for 69,870 cases, the largest number of patients diagnosed with mumps. The annual incidence of mumps increased every year (poisson regression, hazard ratio [HR] 1.026, 95% confidence interval [CI] 1.024-1.027; p<0.025). The risk of mumps was lower in females than that in males (poisson regression, HR 0.594, 95% CI 0.589-0.599; p<0.001). Of the 199,186 patients diagnosed with mumps, 3,872 patients (1.9%) had related complications. Among the mumps complications, the most diagnosed complication was mumps orchitis, which was seen in 41.8% of the males. Mumps orchitis cases accounted for less than 1.5% of the patients with mumps in minors under the age of 20 years and was somewhat higher in 2009 and 2013-2015. CONCLUSIONS: Among the complications related to mumps, meningitis was most common in females, while orchitis was dominant in males. Mumps orchitis also shows periodic outbreaks but is particularly prevalent in adults, which suggests the potential need for additional vaccination against mumps.

Impact of Alcohol Consumption on Quality of Life, Depressive Mood and Metabolic Syndrome in Obstructive Lung Disease Patients: Analysis of Data from Korean National Health and Nutrition Examination Survey from 2014 and 2016.

BACKGROUND: The objective of this study was to investigate whether alcohol consumption might affect the quality of life (QOL), depressive mood, and metabolic syndrome in patients with obstructive lung disease (OLD). METHODS: Data were obtained from the Korean National Health and Nutrition Examination Survey from 2014 and 2016. OLD was defined as spirometry of forced expiratory volume in 1 second/forced vital capacity <0.7 in those aged more than 40 years. QOL was evaluated using the European Quality of Life Questionnaire-5D (EQ-5D) index. Patient Health Questionnaire-9 (PHQ-9) was used to assess the severity of depressive mood. Alcohol consumption was based on a history of alcohol ingestion during the previous month. RESULTS: A total of 984 participants with OLD (695 males, 289 females, age 65.8±9.7 years) were enrolled. The EQ-5D index was significantly higher in alcohol drinkers (n=525) than in non-alcohol drinkers (n=459) (0.94±0.11 vs. 0.91±0.13, p=0.002). PHQ- 9 scores were considerably lower in alcohol drinkers than in non-alcohol drinkers (2.15±3.57 vs. 2.78±4.13, p=0.013). However, multiple logistic regression analysis showed that alcohol consumption was not associated with EQ-5D index or PHQ-9 score. Body mass index ≥25 kg/m2, triglyceride ≥150 mg/dL, high-density lipoprotein <40 mg/dL in men and <50 mg/dL in women, and blood pressure ≥130/85 mm Hg were significantly more common in alcohol drinkers than in non-alcohol drinkers (all p<0.05). CONCLUSION: Alcohol consumption did not change the QOL or depressive mood of OLD patients. However, metabolic syndrome-related factors were more common in alcohol drinkers than in non-alcohol drinkers.

A novel repeat sequence-based PCR (rep-PCR) using specific repeat sequences of Mycobacterium intracellulare as a DNA fingerprinting.

Repetitive sequence-based PCR (rep-PCR) is a potential epidemiological technique that can provide high-throughput genotype fingerprints of heterogeneous Mycobacterium strains rapidly. Previously published rep-PCR primers, which are based on nucleotide sequences of Gram-negative bacteria may have low specificity for mycobacteria. Moreover, it was difficult to ensure the continuity of the study after the commercial rep-PCR kit was discontinued. Here, we designed a novel rep-PCR for Mycobacterium intracellulare, a major cause of nontuberculous mycobacterial pulmonary disease with frequent recurrence. We screened the 7,645 repeat sequences for 200 fragments from the genome of M. intracellulare ATCC 13950 in silico, finally generating five primers with more than 90% identity for a total of 226 loci in the genome. The five primers could make different band patterns depending on the genome of three different M. intracellulare strains using an in silico test. The novel rep-PCR with the five primers was conducted using 34 bacterial samples of 7 species containing 25 M. intracellulare clinical isolates, compared with previous published rep-PCRs. This shows distinguished patterns depending on species and blotting assay for 6 species implied the sequence specificity of the five primers. The Designed rep-PCR had a 95-98% of similarity value in the reproducibility test and showed 7 groups of fingerprints in M. intracellulare strains. Designed rep-PCR had a correlation value of 0.814 with VNTR, reference epidemiological method. This study provides a promising genotype fingerprinting method for tracing the recurrence of heterogeneous M. intracellulare.

COVID-19 Vaccine-Associated Pneumonitis in the Republic of Korea: A Nationwide Multicenter Survey.

BACKGROUND: Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. METHODS: In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. RESULTS: From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26.COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. CONCLUSION: These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.

Lipocalin-2 promotes acute lung inflammation and oxidative stress by enhancing macrophage iron accumulation.

Lipocalin-2 (LCN2) is an acute-phase protein that regulates inflammatory responses to bacteria or lipopolysaccharide (LPS). Although the bacteriostatic role of LCN2 is well studied, the function of LCN2 in acute lung damage remains unclear. Here, LCN2 knockout (KO) mice were used to investigate the role of LCN2 in LPS-treated mice with or without recombinant LCN2 (rLCN2). In addition, we employed patients with pneumonia. RAW264.7 cells were given LCN2 inhibition or rLCN2 with or without iron chelator deferiprone. LCN2 KO mice had a higher survival rate than wild-type (WT) mice after LPS treatment. In addition to elevated LCN2 levels in serum and bronchoalveolar lavage fluid (BALF), LPS treatment also increased LCN2 protein in alveolar macrophage lysates of BALF. LCN2 deletion attenuated neutrophil and macrophage infiltration in the lungs of LPS-treated mice as well as serum and BALF interleukin-6 (IL-6). Circulating proinflammatory cytokines and LCN2-positive macrophages were prominently increased in the BALF of pneumonia patients. In addition to increase of iron-stained macrophages in pneumonia patients, increased iron-stained macrophages and oxidative stress in LPS-treated mice were inhibited by LCN2 deletion. In contrast, rLCN2 pretreatment aggravated lung inflammation and oxidative stress in LPS-treated WT mice and then resulted in higher mortality. In RAW264.7 cells, exogenous LCN2 treatment also increased inflammation and oxidative stress, whereas LCN2 knockdown markedly diminished these effects. Furthermore, deferiprone inhibited inflammation, oxidative stress, and phagocytosis in RAW264.7 cells with high LCN2 levels, as well as LPS-induced acute lung injury in WT and LCN2 KO mice. Thus, these findings suggest that LCN2 plays a key role in inflammation and oxidative stress following acute lung injury and that LCN2 is a potential therapeutic target for pneumonia or acute lung injury.

Serum Fibrinogen as a Biomarker for Disease Severity and Exacerbation in Patients with Non-Cystic Fibrosis Bronchiectasis.

Background: Serum biomarkers associated with severe non-cystic fibrosis (CF) bronchiectasis are currently lacking. We assessed the association of serum fibrinogen, adiponectin, and angiopoietin-2 levels with the severity and exacerbation of bronchiectasis. Methods: Serum levels of fibrinogen, adiponectin, and angiopoietin-2 were measured and compared in patients with stable non-CF bronchiectasis (n = 61) and healthy controls (n = 16). The correlations between the three biomarkers and the bronchiectasis severity index (BSI) or FACED scores were assessed. Univariate and multivariate linear regression analyses were performed to identify variables independently associated with BSI and FACED scores in patients with bronchiectasis. Additionally, the exacerbation-free survival was compared between groups of patients with high and low fibrinogen levels, while the predictors of exacerbation were analyzed using Cox proportional hazards regression. Results: Patients with non-CF bronchiectasis carried higher fibrinogen (3.00 ± 2.31 vs. 1.52 ± 0.74 µg/mL; p = 0.016) and adiponectin (12.3 ± 5.07 vs. 9.17 ± 5.30 µg/mL; p = 0.031) levels compared with healthy controls. The serum level of angiopoietin-2 was comparable between the two groups (1.49 ± 0.96 vs. 1.21 ± 0.79 ng/mL, p = 0.277). Correlations of adiponectin and angiopoietin-2 with BSI and FACED scores were not significant. However, there were significant correlations between fibrinogen and both BSI (r = 0.428) and FACED scores (r = 0.484). Multivariate linear regression analysis revealed that fibrinogen level was an independent variable associated with both BSI and FACED scores. A total of 31 (50.8%) out of 61 patients experienced exacerbation during the follow-up period of 25.4 months. Exacerbation-free survival was significantly longer in patients with low fibrinogen levels than in those with high fibrinogen (log-rank test, p = 0.034). High fibrinogen levels and Pseudomonas colonization were independent risk factors for future exacerbation (HR 2.308; p = 0.03 and HR 2.555; p = 0.02, respectively). Conclusions: Serum fibrinogen, but not adiponectin or angiopoietin-2, is a potential biomarker closely associated with the severity and exacerbation of non-CF bronchiectasis.

Impact of the revised definition on incidence and outcomes of acute exacerbation of idiopathic pulmonary fibrosis.

The revised definition of acute exacerbation (AE) in idiopathic pulmonary fibrosis (IPF) was proposed in 2016, but changes in the incidence and impact on prognosis of the re-defined AE compared to those of the previous definition remain unclear. Clinical data of 445 patients with IPF (biopsy proven cases: 165) were retrospectively reviewed. The median follow-up period was 36.8 months and 17.5% (n = 78) experienced AE more than once. The 1- and 3-year incidence rates of AE were 6.7% and 16.6%, respectively, and idiopathic AE accounted for 82.1% of AE. Older age, lower diffusing capacity of the lung for carbon monoxide and 10% relative decline in forced vital capacity for 6 months were independently associated with AE. The in-hospital mortality rate following AE was 29.5%. In the multivariable analysis, AE was independently associated with poor prognosis in patients with IPF. Compared to the old definition, the revised definition relatively increased the incidence of AE by 20.4% and decreased the in-hospital mortality by 10.1%. Our results suggest that the revised definition affects approximately 20% increase in the incidences and 10% reduction in the in-hospital mortality of AE defined by the past definition.

Comparison of Clinical Features and Outcomes between SARS-CoV-2 and Non-SARS-CoV-2 Respiratory Viruses Associated Acute Respiratory Distress Syndrome: Retrospective Analysis.

Although a few studies comparing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and non-SARS-CoV-2 respiratory viruses have been reported, clinical features and outcomes comparing SARS-CoV-2 and non-SARS-CoV-2 respiratory viruses associated acute respiratory distress syndrome (ARDS) are still lacking. We retrospectively identified patients with SARS-CoV-2 (November 2020 to January 2022) and non-SARS-CoV-2 respiratory viruses associated ARDS (February 2015 to November 2020) at a single tertiary hospital. Their clinical data were obtained by medical record review. All viral infections were confirmed by RT-PCR. Thirty-one SARS-CoV-2 and seventy-one patients with non-SARS-CoV-2 respiratory viruses associated ARDS patients were identified. Influenza (62%) was the most common in non-SARS-CoV-2 respiratory viruses associated ARDS patients. Patients with SARS-CoV-2 were more likely to be female and had higher body mass index, lower clinical frailty, APACHE II, and SOFA score than those with non-SARS-CoV-2 respiratory viruses. All patients with SARS-CoV-2 were treated with corticosteroids and used more high-flow nasal oxygen than those with non-SARS-CoV-2 respiratory viruses. The concomitant respiratory bacterial infection was significantly higher in non-SARS-CoV-2 respiratory viruses than SARS-CoV-2. Although there were no significant differences in the 28-, 60-day, and in-hospital mortality rates between SARS-CoV-2 and non-SARS-CoV-2 respiratory viruses associated ARDS, the duration of mechanical ventilation and length of hospital stay were significantly longer in patients with SARS-CoV-2 than those with non-SARS-CoV-2 respiratory viruses. Although the severity of illness and the concomitant bacterial infection rate were lower in patients with SARS-CoV-2 associated ARDS, mortality rates did not differ from non-SARS-CoV-2 respiratory viruses associated ARDS.

Clinical Usefulness of Red Cell Distribution Width/Albumin Ratio to Discriminate 28-Day Mortality in Critically Ill Patients with Pneumonia Receiving Invasive Mechanical Ventilation, Compared with Lacate/Albumin Ratio: A Retrospective Cohort Study.

The value of the red cell distribution width (RDW) is associated with prognosis in critically ill patients. A simplex combined index-the RDW/albumin ratio-has been proposed for the prediction of mortality, as has the lactate/albumin ratio. The aim of this study was to evaluate the clinical utility of the RDW/albumin ratio regarding 28-day mortality in critically ill patients with pneumonia. Clinical data of critically ill patients with pneumonia who were hospitalized in the medical intensive care unit from May 2018 to December 2020, and received invasive mechanical ventilation (IMV), were reviewed retrospectively. The values of RDW, lactate, and albumin measured at the time of IMV, were used for the index calculations. Of the 234 patients, the median age was 76 years, and 74.2% were male. The 28-day mortality rate was 47.3%. The median RDW/albumin ratio was significantly higher in non-survivors than survivors at 28 days (5.8 vs. 4.9, p < 0.001). A higher RDW/albumin ratio was significantly associated with increased 28-day mortality (odds ratio [OR] 1.338, 95% confidence interval [CI] 1.094-1.637, p = 0.005). The area under the receiver operating curve (AUROC) was 0.694 (95% CI: 0.630-758, p < 0.005) to discern 28-day mortality without significant difference, compared with that of the lactate/albumin ratio. Our data suggest that high RDW/albumin ratio has a similar predictability to the lactate/albumin ratio in critically ill patients with pneumonia receiving IMV.

Impact of coexistent preserved ratio impaired spirometry on the survival of patients with lung cancer: Analysis of data from the Korean Association for Lung Cancer Registry.

BACKGROUND: Preserved ratio impaired spirometry (PRISm) is a common spirometric pattern that is associated with respiratory symptoms and higher mortality rates. However, the relationship between lung cancer and PRISm remains unclear. This study investigated the clinical characteristics of lung cancer patients with PRISm and the potential role of PRISm as a prognostic factor. METHODS: We retrospectively reviewed data collected from 2014 to 2015 in the Korean Association for Lung Cancer Registry. We classified all patients into three subgroups according to lung function as follows: normal lung function; PRISm (forced expiratory volume in 1 s [FEV1 ] < 80% predicted and FEV1 /forced vital capacity [FVC] ≥ 0.7); and chronic obstructive pulmonary disease (COPD; FEV1/FVC < 0.7). In non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), the overall survival period was compared among the three subgroups. The prognostic factors were investigated using Cox regression analysis. RESULTS: Of the 3763 patients, 38.6%, 40.1%, and 21.3% had normal lung function, COPD, and PRISm, respectively. Patients with PRISm had poorer overall survival than those with COPD or normal lung function in NSCLC and SCLC (Mantel-Cox log-rank test, p < 0.05). In the risk-adjusted analysis, overall survival was independently associated with COPD (hazard ratio [HR] 1.209, p = 0.027) and PRISm (HR 1.628, p < 0.001) in NSCLC, but was only associated with PRISm (HR 1.629, p = 0.004) in SCLC. CONCLUSIONS: PRISm is a significant pattern of lung function in patients with lung cancer. At the time of lung cancer diagnosis, pre-existing PRISm should be considered a predictive factor of poor prognosis.

Pulmonary mycobacterial infection is associated with increased mortality in patients with acute respiratory distress syndrome.

ABSTRACT: Although pulmonary mycobacterial infection is associated with acute respiratory distress syndrome (ARDS) in critically ill patients, its clinical implication on patients with ARDS has not been clearly elucidated. The aim of study was to investigate the clinical significance of pulmonary mycobacterial infection in patients with ARDS.Between January 2014 and April 2019, medical records of 229 patients with ARDS who met the Berlin criteria and received invasive mechanical ventilation in medical intensive care unit were reviewed. Clinical characteristics and the rate of mortality between patients with and without pulmonary mycobacterial infection were compared. Factors associated with a 28-day mortality were analyzed statistically.Twenty two (9.6%) patients were infected with pulmonary mycobacteria (18 with tuberculosis and 4 with non-tuberculous mycobacteria). There were no differences in baseline characteristics, the severity of illness scores. Other than a higher rate of renal replacement therapy required in those without pulmonary mycobacterial infection, the use of adjunctive therapy did not differ between the groups. The 28- day mortality rate was significantly higher in patients with pulmonary mycobacterial infection (81.8% vs 58%, P = .019). Pulmonary mycobacterial infection was significantly associated with 28-day mortality (hazard ratio 1.852, 95% confidence interval 1.108-3.095, P = .019).Pulmonary mycobacterial infection was associated with increased 28-day mortality in patients with ARDS.

Serum hepatocyte growth factor as a predictor of disease severity and future exacerbations in patients with non-cystic fibrosis bronchiectasis.

BACKGROUND: Serum biomarkers associated with the severity of non-cystic fibrosis (CF) bronchiectasis are insufficient. This study determined the association of serum hepatocyte growth factor (HGF), osteopontin, and pentraxin-3 levels with disease severity and exacerbation in patients with non-CF bronchiectasis. METHODS: Serum levels of HGF, osteopontin, and pentraxin-3 were measured in patients with clinically stable non-CF bronchiectasis (n = 61). The correlation between the biomarkers and bronchiectasis severity index (BSI) and FACED score was assessed using univariate and multivariate linear regression analyses. Predictive variables associated with exacerbation were analyzed using a Cox proportional hazards model and the time to first exacerbation in high and low HGF groups during the observation period was compared using Kaplan-Meier survival curves. RESULTS: The BSI showed significant correlation with HGF (r = 0.423; p = 0.001) and pentraxin-3 (r = 0.316; p = 0.013). The FACED score was significantly correlated with HGF (r = 0.406; p = 0.001). Univariate and multivariate linear regression analysis revealed that serum level of HGF was independently associated with both scoring systems. The high HGF group showed a significantly shorter time to first exacerbation (Log-rank test, p = 0.014). Multivariate Cox proportional hazards regression analysis revealed that high serum HGF level and colonization with non-pseudomonas organisms were independent predictors of future exacerbations (HR 2.364; p = 0.024 and HR 2.438; p = 0.020, respectively). CONCLUSION: Serum level of HGF is a potential biomarker that is closely associated with disease severity and future risk of exacerbations in patients with non-CF bronchiectasis.

Serum albumin is a predictor of respiratory hospitalization in patients with bronchiectasis.

We evaluated serum albumin as an index for predicting respiratory hospitalization in patients with bronchiectasis. We retrospectively reviewed the medical records of 177 patients with bronchiectasis, categorized them into low and normal albumin groups, and compared their clinical characteristics. The prediction of respiratory hospitalization by factors such as serum albumin level, bronchiectasis severity index (BSI), and FACED score (an acronym derived from five variables of forced expiratory volume in 1 s; FEV1, age, chronic colonization of Pseudomonas aeruginosa, extent of bronchiectasis, and dyspnea) was assessed. There were 15 and 162 patients categorized in the low and normal albumin groups, respectively. The low albumin group had lower body mass index and forced expiratory volume in 1 s, and higher age, frequency of previous respiratory hospitalization, percentage of Pseudomonas colonization, number of affected lobes, BSI and FACED scores, and C-reactive protein (CRP) level, than the normal albumin group. The areas under the receiver operating characteristic curve of serum albumin level and BSI and FACED scores for predicting respiratory hospitalization were 0.732 (95% confidence interval (CI), 0.647-0.816), 0.873 (95% CI, 0.817-0.928), and 0.708 (95% CI, 0.618-0.799), respectively. Albumin level, CRP, modified Medical Research Council score, and chronic Pseudomonas aeruginosa (and other organisms) colonization were independent risk factors for respiratory hospitalization. Low serum albumin level was associated with worse clinical condition, higher severity scores, and respiratory hospitalization in patients with bronchiectasis.

Identification of Nontuberculous Mycobacteria in Patients with Pulmonary Diseases in Gyeongnam, Korea, Using Multiplex PCR and Multigene Sequence-Based Analysis.

BACKGROUND: Nontuberculous mycobacteria (NTM) are widely present in environments, such as soil and water, and have recently been recognized as important pathogenic bacteria. The incidence of NTM-related infections is steadily increasing. As the diagnosis and treatment of NTM infection should be distinguished from tuberculosis, and the treatment should be specific to the species of NTM acquired, accurate species identification is required. METHODS: In this study, two-step multiplex PCR (mPCR) and multigene sequence-based analysis were used to accurately identify NTM species in 320 clinical isolates from Gyeongsang National University Hospital (GNUH). In particular, major mycobacterial strains with a high isolation frequency as well as coinfections with multiple species were diagnosed through two-step mPCR. Multigene sequencing was performed to accurately identify other NTM species not detected by mPCR. Variable regions of the genes 16S rRNA, rpoB, hsp65, and 16S-23S rRNA internal transcribed spacer were included in the analysis. RESULTS: Two-step mPCR identified 234 (73.1%) cases of M. intracellulare, 26 (8.1%) cases of M. avium subsp. avium, and 13 (4.1%) cases of M. avium subsp. hominissuis infection. Additionally, 9 (2.8%) M. fortuitum, 9 (2.8%) M. massiliense, 2 (0.6%) M. abscessus, and 4 (1.2%) M. kansasii isolates were identified. Coinfection was identified in 7 (2.2%) samples. The sixteen samples not classified by two-step mPCR included 6 (1.9%) cases of M. chimaera, 4 (1.3%) M. gordonae, 1 (0.3%) M. colombiense, 1 (0.3%) M. mageritense, and 1 (0.3%) M. persicum identified by sequence analysis. CONCLUSIONS: The results of this study suggest a strategy for rapid detection and accurate identification of species using two-step mPCR and multigene sequence-based analysis. To the best of our knowledge, this study is the first to report the identification of NTM species isolated from patients in Gyeongnam/Korea.