BACKGROUND: The aberrant, leukemia-associated antigen expression patterns allow us to discriminate leukemic blasts from normal precursor cells. Our major goal was to determine a guideline for the detection of minimal residual disease using CD20+/CD34+ and myeloid Ag+/CD19+ combination in the bone marrow of acute leukemia in complete remission (CR) after chemotherapy. METHODS: Bone marrow samples from 117 patients with acute leukemia in complete remission after chemotherapy and from 22 healthy controls were immunophenotyped by triple staining and measured by flow cytometry. RESULTS: The CD20+/CD34+ cells in the large lymphocyte gate (R1) ranged from 0% to 3.24% (0.8+/-0.82%, P=0.000) in CD20+/CD34+ B-lineage ALL CR (N=31), from 0.03% to 4.2% (0.7+/-0.83%, P=0.000) in CD20-/CD34- B-lineage ALL CR (N=66), from 0.1% to 0.96% (0.45+/-0.32%, P=0.016) in T-ALL CR (N=10), and from 0.02% to 0.48% (0.18+/-0.15%, P=0.776) in AML CR (N=10). The CD13,33+/CD19+ cells in R1 gate ranged from 0% to 2.69% (0.37+/-0.48%, P<0.001) in CD13,33+/CD19+ B-lineage ALL CR (N=31), from 0% to 1.8% (0.31+/-0.28%, P<0.001) in CD13,33-/CD19+B-lineage ALL CR (N=65), from 0.02% to 0.64% (0.29+/-0.22%, P=0.071) in T-ALL CR (N=9), and from 0% to 0.17% (0.07+/-0.09%, P=0.341) in AML CR (N=3). CONCLUSIONS: Using an immunophenotypic method for the detection of early relapse or minimal residual disease of B-lineage ALL bone marrow in CR after chemotherapy, different cutoff values should be applied according to antigen combination and gating. When the proportion of aberrant antigen combination was less than 5% in large lymphocyte gate, the results should be interpreted with caution.
Acute Disease ; Antigens, CD/*metabolism ; Antigens, CD19/metabolism ; Antigens, CD20/metabolism ; Antigens, CD34/metabolism ; Antigens, Differentiation, Myelomonocytic/analysis/metabolism ; Bone Marrow Cells/*classification/metabolism ; Flow Cytometry ; Hematopoietic Stem Cells/classification/metabolism ; Humans ; Immunophenotyping ; Leukemia/*diagnosis/drug therapy ; Leukemia, Myeloid, Acute/diagnosis/drug therapy ; Neoplasm, Residual ; Remission Induction ; Tumor Markers, Biological/immunology

Edwardsiella tarda is a member of the family Enterobacteriaceae, commonly found in tropical and subtropical aquatic environments. Most E. tarda infections are linked to exposure to water or animals that inhabit water. However, it is still an uncommon pathogen in humans and causes mainly watery diarrhea. We describe a case of liver abscess caused by E. tarda. A 60-yr-old Korean man, with underlying diabetes mellitus, had a 10-day stay in Egypt 15 days before presentation. Ultrasound-guided percutaneous transhepatic abscess aspiration was performed. Pus culture revealed E. tarda, which was susceptible to all the antibiotics commonly used against Gram-negative organisms. The patient was treated with cefobactam for 10 days and piperacillin/tazobactam for another 5 days combined with an additional abscess aspiration due to recurrent fever. This therapy led to clinical improvement. The possible source of infection in this case may have been the drinking water supplied during travel in Egypt, but we cannot completely rule out a domestic source, because a liver abscess caused by E. tarda has been reported in a Japanese patient without travel history. Considering the Korean custom of eating raw fish or shrimp, climate changes, and increasing international travel, infections due to E. tarda may increase in Korea. Clinical microbiologists should be aware of this potential pathogen, and prompt investigation of the infection source and site is needed.
Abscess ; Animals ; Anti-Bacterial Agents ; Asian Continental Ancestry Group ; Climate Change ; Diabetes Mellitus ; Diarrhea ; Drinking Water ; Eating ; Edwardsiella ; Edwardsiella tarda ; Egypt ; Enterobacteriaceae ; Fever ; Humans ; Korea ; Liver ; Liver Abscess ; Suppuration ; Water

Purpose: Coronavirus disease-2019 (COVID-19) is a novel respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); there are few specific treatments. Convalescent plasma (CP), donated by people who have recovered from COVID-19, is an investigational therapy for severe or critically ill patients with COVID-19. Materials and Methods: This retrospective cohort study evaluated the effectiveness of CP therapy in patients with severe or lifethreatening cases of COVID-19 at two hospitals in Seoul, Korea, between May and September 2020. Clinical outcomes were evaluated in 20 patients with CP therapy in a descriptive manner. Additionally, the changes in cycle threshold (Ct) values of 10 patients with CP therapy were compared to those of 10 controls who had the same (±0.8) initial Ct values but did not receive CP. Results: Of the 20 patients (mean age 66.6 years), 18 received high-dose oxygen therapy using mechanical ventilators or high-flow nasal cannulas. Systemic steroids were administered to 19 patients who received CP. The neutralizing antibody titers of the administered CP were between 1:80 and 1:10240. There were two ABO-mismatched transfusions. The World Health Organization ordinal scale score and National Institutes of Health severity score improved in half of the patients within 14 days. Those who received CP showed a higher increase in Ct values at 24 h and 72 h after CP therapy compared to controls with similar initial Ct values (p=0.002).No transfusion-related side effects were observed. Conclusion CP therapy may be a potential therapeutic option in severe or critically ill patients with COVID-19.

Purpose: Coronavirus disease-2019 (COVID-19) is a novel respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); there are few specific treatments. Convalescent plasma (CP), donated by people who have recovered from COVID-19, is an investigational therapy for severe or critically ill patients with COVID-19. Materials and Methods: This retrospective cohort study evaluated the effectiveness of CP therapy in patients with severe or lifethreatening cases of COVID-19 at two hospitals in Seoul, Korea, between May and September 2020. Clinical outcomes were evaluated in 20 patients with CP therapy in a descriptive manner. Additionally, the changes in cycle threshold (Ct) values of 10 patients with CP therapy were compared to those of 10 controls who had the same (±0.8) initial Ct values but did not receive CP. Results: Of the 20 patients (mean age 66.6 years), 18 received high-dose oxygen therapy using mechanical ventilators or high-flow nasal cannulas. Systemic steroids were administered to 19 patients who received CP. The neutralizing antibody titers of the administered CP were between 1:80 and 1:10240. There were two ABO-mismatched transfusions. The World Health Organization ordinal scale score and National Institutes of Health severity score improved in half of the patients within 14 days. Those who received CP showed a higher increase in Ct values at 24 h and 72 h after CP therapy compared to controls with similar initial Ct values (p=0.002).No transfusion-related side effects were observed. Conclusion CP therapy may be a potential therapeutic option in severe or critically ill patients with COVID-19.