BACKGROUND: Burn wounds lack normal barriers that protect against pathogenic bacteria, and burn patients are easily colonized and infected by Staphylococcus aureus. Toxic shock syndrome (TSS) is a rare but fatal disease caused by S. aureus. A lack of detectable antibodies to TSS toxin-1 (TSST-1) in serum indicates susceptibility to TSS. METHODS: A total of 207 patients (169 men and 38 women; median age, 42.5 yr) admitted to a burn center in Korea were enrolled in this study. The serum antibody titer to TSST-1 was measured by sandwich ELISA. S. aureus isolates from the patients' nasal swab culture were tested for TSST-1 toxin production by PCR-based detection of the TSST-1 toxin gene. RESULTS: One hundred seventy-four (84.1%) patients showed positive results for antibody against TSST-1. All patients aged > or =61 yr (n=28) and <26 months (n=7) were positive for the anti-TSST-1 antibody. S. aureus was isolated from 70 patients (33.8%), and 58.6% of the isolates were methicillin resistant. Seventeen patients were colonized with TSST-1-producing S. aureus. The antibody positivity in these 17 carriers was 88.2%, and the positivity in the non-carriers was 83.7%. CONCLUSIONS: Most burn patients had antibody to TSST-1, and nasal colonization with TSST-1-producing S. aureus was associated with positive titers of anti-TSST-1 antibody. Additionally, patients with negative titers of anti-TSST-1 antibody might be susceptible to TSS.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antibodies, Bacterial/*blood ; Bacterial Toxins/genetics/immunology/*metabolism ; Burns/blood/*immunology/*microbiology/pathology ; Child ; Child, Preschool ; Enterotoxins/genetics/immunology/*metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Infant ; Male ; Middle Aged ; Nasal Cavity/microbiology ; Polymerase Chain Reaction ; Prevalence ; Staphylococcal Infections/epidemiology ; Staphylococcus aureus/isolation & purification/*metabolism ; Superantigens/genetics/immunology/*metabolism ; Young Adult

PURPOSE: The management of metal-induced field inhomogeneities is one of the major concerns of distortion-free magnetic resonance images near metallic implants. The recently proposed method called “Slice Encoding for Metal Artifact Correction (SEMAC)” is an effective spin echo pulse sequence of magnetic resonance imaging (MRI) near metallic implants. However, as SEMAC uses the noisy resolved data elements, SEMAC images can have a major problem for improving the signal-to-noise ratio (SNR) without compromising the correction of metal artifacts. To address that issue, this paper presents a novel reconstruction technique for providing an improvement of the SNR in SEMAC images without sacrificing the correction of metal artifacts. MATERIALS AND METHODS: Low-rank approximation in each coil image is first performed to suppress the noise in the slice direction, because the signal is highly correlated between SEMAC-encoded slices. Secondly, SEMAC images are reconstructed by the best linear unbiased estimator (BLUE), also known as Gauss-Markov or weighted least squares. Noise levels and correlation in the receiver channels are considered for the sake of SNR optimization. To this end, since distorted excitation profiles are sparse, l1 minimization performs well in recovering the sparse distorted excitation profiles and the sparse modeling of our approach offers excellent correction of metal-induced distortions. RESULTS: Three images reconstructed using SEMAC, SEMAC with the conventional two-step noise reduction, and the proposed image denoising for metal MRI exploiting sparsity and low rank approximation algorithm were compared. The proposed algorithm outperformed two methods and produced 119% SNR better than SEMAC and 89% SNR better than SEMAC with the conventional two-step noise reduction. CONCLUSION: We successfully demonstrated that the proposed, novel algorithm for SEMAC, if compared with conventional de-noising methods, substantially improves SNR and reduces artifacts.
Artifacts ; Least-Squares Analysis ; Magnetic Resonance Imaging* ; Methods ; Noise ; Signal-To-Noise Ratio

Regulatory T cells (Treg) naturally rein in immune attacks, and they can inhibit rejection of transplanted organs and even reverse the progression of autoimmune diseases in mice. The initial safety trials of Treg against graft-versus-host disease (GVHD) provided evidence that the adoptive transfer of Treg is safe and capable of limiting disease progression. Supported by such evidence, numerous clinical trials have been actively investigating the efficacy of Treg targeting autoimmune diseases, type I diabetes, and organ transplant rejection, including kidney and liver. The limited quantity of Treg cells harvested from peripheral blood and subsequent in vitro culture have posed a great challenge to large-scale clinical application of Treg; nevertheless, the concept of CAR (chimeric antigen receptor)-Treg has emerged as a potential resolution to the problem. Recently, two CAR-T therapies, tisagenlecleucel and axicabtagene ciloleucel, were approved by the US FDA for the treatment of refractory or recurrent acute lymhoblastic leukemia. This approval could serve as a guideline for the production protocols for other genetically engineered T cells for clinical use as well. The phase I and II clinical trials of these agents has demonstrated that genetically engineered and antigen-targeting T cells are safe and efficacious in humans. In conclusion, both the promising results of Treg cell therapy from the clinical studies and the recent FDA approval of CAR-T therapies are paving the way for CAR-Treg therapy in clinical use.
Adoptive Transfer ; Animals ; Autoimmune Diseases ; Cell- and Tissue-Based Therapy* ; Disease Progression ; Graft vs Host Disease ; Humans ; In Vitro Techniques ; Kidney ; Leukemia ; Liver ; Mice ; T-Lymphocytes ; T-Lymphocytes, Regulatory* ; Transplantation ; Transplants

BACKGROUND: Postoperative delirium has been suggested as a significant predictor of postoperative morbidity and mortality in elderly patients. They usually have multiple comorbidities, including cardiovascular, respiratory, renal, and neurologic disease. We aimed to determine the incidence rate and modifiable risk factors of postoperative delirium following total knee arthroplasty in elderly. METHODS: We reviewed the medical records of 318 elderly patients (age >65 years) underwent unilateral total knee arthroplasty between 2009 and 2016. Patient demographics, American Society of Anesthesiologists physical status, preoperative comorbidities, type and duration of anesthesia and surgery, length of hospital stay, ambulation ability, frequency of intraoperative hypotension, frequency of hypothermia, whether the patient was transfused or heparinized, and perioperative laboratory results were evaluated. Univariate and multivariate logistic regression analyses were used to identify significant independent predictors of postoperative delirium. RESULTS: The incidence rate of postoperative delirium was 6% in this study. Univariate analysis showed that postoperative delirium was significantly associated with age, body mass index, general anesthesia, anesthesia time, preoperative dementia, intraoperative hypotension, preoperative hemoglobin, blood transfusion, and intraoperative hypothermia. Preoperative dementia (odds ratio [OR] = 8.80), intraoperative hypotension (OR = 1.06), and preoperative hemoglobin (OR = 0.66) were significant independent risk factors of postoperative delirium. CONCLUSIONS: Preoperative dementia is the most important risk factor of postoperative delirium. High-risk patients undergoing total knee arthroplasty should be thoroughly evaluated and their dementia should be managed preoperatively. Adequate management of preoperative hemoglobin and intraoperative hypotension might also be helpful in reducing the incidence of postoperative delirium in this population.
Aged* ; Anesthesia ; Anesthesia, General ; Arthroplasty, Replacement, Knee* ; Blood Transfusion ; Body Mass Index ; Comorbidity ; Delirium* ; Dementia ; Demography ; Heparin ; Humans ; Hypotension ; Hypothermia ; Incidence ; Length of Stay ; Logistic Models ; Medical Records ; Mortality ; Postoperative Complications ; Risk Factors* ; Walking

BACKGROUND: Coagulase is produced by all strains of Staphylococcus aureus. The 3' coding region of the coagulase (coa) gene contains varying numbers of 81 bp tandem repeats. S. aureus produces a variety of extracellular protein toxins. Here, we typed S. aureus strains isolated from blood by coa gene restriction fragment length polymorphism (RFLP) patterns and toxin gene profiles. METHODS: A total of 120 strains of S. aureus were isolated from blood cultures during 2003-2006 at Kangdong Sacred Heart Hospital. The isolates were typed by PCR RFLP analysis of the coa gene and by multiplex PCR for detection of genes encoding enterotoxins (sea, seb, sec, sed, and see), toxic shock syndrome toxin-1 (tst), exfoliative toxins (eta and etb), mecA and femA. RESULTS: All the S. aureus strains were classified into 16 types on the basis of coa gene RFLP and could be further differentiated into 34 types according to the combined patterns of coa gene RFLP and toxin gene profiles. Of 85 methicillin-resistant S. aureus (MRSA) strains, 43 (50.6%) and 36 (42.4%) belonged to the RFLP pattern L5 and pattern L1, respectively. MRSA strains belonging to pattern L5 frequently carried tst (93.0%) or sec gene (81.4%), and strains belonging to pattern L1 frequently carried sea (88.9%) or see gene (44.4%). The rate of the pattern L5 in MRSA strains increased over the past few years and was higher in intensive care unit than in other wards. CONCLUSIONS: We typed S. aureus strains isolated from blood on the basis of coa gene RFLP and toxin genes. The strains belonging to coa gene RFLP pattern L5 and L1 appeared to be the major types of MRSA isolasted from bacteremia and revealed specific toxin gene profiles according to the coa gene RFLP patterns.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Bacterial Proteins/genetics ; Bacterial Typing Techniques ; Child ; Child, Preschool ; Coagulase/*genetics ; Female ; Humans ; Infant ; Male ; Methicillin Resistance/genetics ; Middle Aged ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Staphylococcal Infections/*diagnosis/genetics/microbiology ; Staphylococcus aureus/*classification/genetics/isolation & purification ; Toxins, Biological/*genetics ; Young Adult

Kikuchi disease, also called histiocytic necrotizing lymphadenitis, is an uncommon, idiopathic and generally self-limited disease, characterized by cervical lymphadenopathy. It can present systemic symptoms and signs, but ocular involvement is unusual. We report a 35-year-old woman who presented sudden decreased visual acuity and a swollen lymph node on the left side of her neck. On laboratory findings, there were no evidences of infection, autoimmune disease and systemic vasculitis. She was diagnosed with Kikuchi disease and bilateral retinal vasculitis by histologic analysis of lymph node, fundoscopy and fluorescein angiography.
Adult ; Autoimmune Diseases ; Female ; Fluorescein Angiography ; Histiocytic Necrotizing Lymphadenitis ; Humans ; Lymph Nodes ; Lymphatic Diseases ; Neck ; Retinal Vasculitis ; Retinaldehyde ; Systemic Vasculitis ; Visual Acuity

BACKGROUND: The MicroScan MICroSTREP plus panel for susceptibility testing of various streptococci, including Streptococcus pneumoniae, has recently been introduced in Korea. The current study evaluated the usefulness of MicroScan MICroSTREP plus panel for antimicrobial susceptibility test of S. pneumoniae. METHODS: A total of 75 clinical isolates of S. pneumoniae were tested for antimicrobial susceptibility to penicillin, cefotaxime, ceftriaxone, meropenem, vancomycin, clindamycin, erythromycin, and levofloxacin with the MicroScan MICroSTREP plus panel and clinical and laboratory standard institute (CLSI) reference broth microdilution method. For 46 of 75 isolates, additional susceptibility tests to penicillin and cefotaxime were performed with Etest. RESULTS: The overall essential agreement of MICs (within one dilution of MICs) defined by the MicroScan MICroSTREP plus panel and reference method was 93.0%. Overall there were 11.7% minor, 0.7% major, and 0.7% very major interpretative category errors observed. The results of antibiotic susceptibility testing by Etest were similar to those obtained by the MicroScan MICroSTREP plus panel. CONCLUSION: The MicroScan MICroSTREP plus panel, a commercial broth microdilution method, has a comparable accuracy to CLSI broth microdilution method for the resistance testing of S. pneumonia. This panel can be used for determining susceptibilities of S. pneumoniae to a wide variety of antimicrobial agents in clinical microbiology laboratories.
Anti-Infective Agents ; Cefotaxime ; Ceftriaxone ; Clindamycin ; Erythromycin ; Korea ; Ofloxacin ; Penicillins ; Pneumonia ; Streptococcus ; Streptococcus pneumoniae ; Thienamycins ; Vancomycin

Chronic renal allograft dysfunction (CRAD) has been the rnost frequent cause of graft failure for last decade. Even in cycloporine era the incidence of CRAD has not changed. From Jan 1992 to Dec 1994 118 kidney transplants performed in Seoul National University Hospital had been entered into our database. All patients had been followed for at least 1 year. CRAD is defined if there had been progressive deterioration of renal function that was not explained by other causes and finally serum creatinine (Scr) had doubled from basal Scr after transplantation and has been maintained. Analyzed factors as follows; HLA misrnatch, living or cadaver transplant, ABO mismatch, acute rejecton (AR), frequency and timing of AR, donor age, recipient age, cold ischmic time, delayed graft function, proteinuria, infection. A CRAD has developed in 27 (23%) patients. The incidence of CRAD with time was analyzed by Kaplan-Meier survival analysis and compared with log-rank test. We concluded that in univariate anlaysis the risk factors are acute rejection, frequency of AR, AR after 3 months after tranplantation, age of recipient<15 and cold ischmic time> 40rnin for living transplants. Although HLAMM=0 significantly decreased the risk of CRAD (P<0.05), there was no difference in renal survival between groups of HLAMM>1. AR and HLAMM (HLAMM=O vs. HLAMM>1) were related each other (P=0.02).
Allografts* ; Cadaver ; Creatinine ; Delayed Graft Function ; Humans ; Incidence ; Kidney ; Kidney Transplantation ; Proteinuria ; Risk Factors* ; Seoul ; Tissue Donors ; Transplants

On 11 February, 2020, the World Health Organization announced that COVID-19 was a novel coronavirus disease first detected in Wuhan, Hubei Province, China. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The complete clinical picture is not fully known. Illness ranges from mild to fatal. The common symptoms include fever, cough, and dyspnea usually developing 2-14 days after exposure. However, diarrhea was present in a few patients with COVID-19. We report a case of COVID-19 mimicking acute colitis.

On 11 February, 2020, the World Health Organization announced that COVID-19 was a novel coronavirus disease first detected in Wuhan, Hubei Province, China. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The complete clinical picture is not fully known. Illness ranges from mild to fatal. The common symptoms include fever, cough, and dyspnea usually developing 2-14 days after exposure. However, diarrhea was present in a few patients with COVID-19. We report a case of COVID-19 mimicking acute colitis.