A Case of Acute Myeloid Leukemia with Myelodysplasia-Related Changes, SET-NUP214 Fusion, and Complex Karyotype.

BACKGROUND: The SET-NUP214 fusion formed by cryptic t(9;9)(q34;q34) or del(9)(q34.11q34.13) is a rare gene rearrangement. This rearrangement has been reported mostly in T-cell acute lymphoblastic leukemia, but only rarely in acute myeloid leukemia (AML). The acute leukemia cases with the SET-NUP214 fusion gene show typical immunophenotype, karyotype, and poor treatment response. However, the cytogenetic or genetic changes in AML with SET-NUP214 fusion are not well understood. METHODS: The diagnosis was made based on a combination of the morphology, immunophenotyping, multiplex reverse transcriptase-polymerase chain reaction, FISH, karyotype, Sanger sequencing, next-generation sequencing, and microarray analysis. RESULTS: The author reports a rare case of AML with myelodysplasia-related changes, SET-NUP214 fusion gene, and complex karyotype that was resistant to induction chemotherapy, making diagnosis and treatment difficult. CONCLUSIONS: Further studies, including cytogenetic and molecular analyses, are needed to determine the pathophysiology and clinical significance for this rare gene rearrangement.

Bone marrow and peripheral blood involvement of relapsed diffuse large B-cell lymphoma after prior cold agglutinin disease.

The author report an interesting case of relapsed diffuse large B-cell lymphoma (DLBCL) with bone marrow (BM) and peripheral blood (PB) involvement after prior cold agglutinin disease (CAD). A minority of patients with DLBCL present with CAD, and BM or PB involvement with CAD are quite rare. Differential diagnosis of patients with CAD should include DLBCL, considering the possibility of BM or even PB involvement.

Comparing SARS-CoV-2 Antibody Responses after Various COVID-19 Vaccinations in Healthcare Workers.

Coronavirus disease 2019 (COVID-19) vaccination began for healthcare workers in South Korea at the end of February 2021. This study investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses after various COVID-19 vaccinations in healthcare workers. Blood specimens of 497 vaccinated healthcare workers were collected. Inoculated vaccines were ChAdOx1 (AstraZeneca/Oxford), BNT162b2 (Pfizer/BioNTech), JNJ-78436735 (Janssen), and mRNA-1273 (Moderna). Each specimen was tested for antibodies against SARS-CoV-2 using Elecsys Anti-SARS-CoV-2 S assay (Roche Diagnostics), SARS-CoV-2 IgG II Quant assay (Abbott), and R-FIND SARS-CoV-2 Neutralizing Antibody kit (SG medical Inc.). A questionnaire was used to investigate adverse events related to vaccination. We found that 99.5% of the subjects showed a 96-100% positive rate in all three antibody assays, regardless of the vaccine type. The antibody-positive rate of completed vaccination groups reached 96-100%, and antibody quantities significantly increased 2 weeks after vaccination. The antibody values measured approximately 3 months after BNT162b2 inoculation significantly correlated with adverse events.

Serological evaluation of patients with coronavirus disease-2019 in Daegu, South Korea.

BACKGROUND: Early and accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical to prevent spread of the infection. Understanding of the antibody response to SARS-CoV-2 in patients with coronavirus disease 2019 (COVID-19) is insufficient, particularly in relation to those whose responses persist for more than 1 month after the onset of symptoms. We conducted a SARS-CoV-2 antibody test to identify factors affecting the serological response and to evaluate its diagnostic utility in patients with COVID-19. METHODS AND FINDING: We collected 1,048 residual serum samples from 396 patients with COVID-19 confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2. The samples had been used for routine admission tests in six healthcare institutions in Daegu. Antibody to SARS-CoV-2 was analyzed and the cutoff index (COI) was calculated for quantitative analysis. The patients' information was reviewed to evaluate the relationship between antibody positivity and clinical characteristics. The anti-SARS-CoV-2 antibody positivity rate was 85% and the average COI was 24·3. The positivity rate and COI increased with time elapsed since symptom onset. Anti-SARS-CoV-2 antibody persisted for at least 13 weeks after symptom onset at a high COI. There was a significant difference in anti-SARS-CoV-2 antibody positivity rate between patients with and without symptoms, but not according to sex or disease course. The descending COI pattern at weeks 1 to 5 after symptom onset was significantly more frequent in patients who died than in those who recovered. CONCLUSIONS: Anti-SARS-CoV-2 antibody persisted for at least 13 weeks at a high COI in patients with COVID-19. A decreasing COI pattern up to fifth week may be associated with a poor prognosis of COVID-19. As new treatments and vaccines are introduced, it is important to monitor continuously the usefulness of anti-SARS-CoV-2 antibody assays.

Comprehensive Laboratory Data Analysis to Predict the Clinical Severity of Coronavirus Disease 2019 in 1,952 Patients in Daegu, Korea.

BACKGROUND: Laboratory parameter abnormalities are commonly observed in COVID-19 patients; however, their clinical significance remains controversial. We assessed the prevalence, characteristics, and clinical impact of laboratory parameters in COVID-19 patients hospitalized in Daegu, Korea. METHODS: We investigated the clinical and laboratory parameters of 1,952 COVID-19 patients on admission in nine hospitals in Daegu, Korea. The average patient age was 58.1 years, and 700 (35.9%) patients were men. The patients were classified into mild (N=1,612), moderate (N=294), and severe (N=46) disease groups based on clinical severity scores. We used chi-square test, multiple comparison analysis, and multinomial logistic regression to evaluate the correlation between laboratory parameters and disease severity. RESULTS: Laboratory parameters on admission in the three disease groups were significantly different in terms of hematologic (Hb, Hct, white blood cell count, lymphocyte%, and platelet count), coagulation (prothrombin time and activated partial thromboplastin time), biochemical (albumin, aspartate aminotransferase, alanine aminotransferase, lactate, blood urea nitrogen, creatinine, and electrolytes), inflammatory (C-reactive protein and procalcitonin), cardiac (creatinine kinase MB isoenzyme and troponin I), and molecular virologic (Ct value of SARS-CoV-2 RdRP gene) parameters. Relative lymphopenia, prothrombin time prolongation, and hypoalbuminemia were significant indicators of COVID-19 severity. Patients with both hypoalbuminemia and lymphopenia had a higher risk of severe COVID-19. CONCLUSIONS: Laboratory parameter abnormalities on admission are common, are significantly associated with clinical severity, and can serve as independent predictors of COVID-19 severity. Monitoring the laboratory parameters, including albumin and lymphocyte count, is crucial for timely treatment of COVID-19.

Prevalence of SARS-CoV-2 Antibody in 2,935 Healthcare Workers at 6 Major Hospitals, Daegu, Korea.

BACKGROUND: In Korea, the first community outbreak of coronavirus disease 2019 (COVID-19) occurred in Daegu on February 18, 2020. This study was performed to investigate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in healthcare workers (HCWs) at 6 major hospitals in Daegu. METHODS: Blood specimens of 2,935 HCWs at 6 major hospitals in Daegu from January 2021 to February 2021 were collected. Every specimen was tested for antibody against SARS-CoV-2 using both Elecsys Anti-SARS-CoV-2 electrochemiluminescence immunoassay (Roche Diagnostics, Rotkreuz, Switzerland) and R-FIND COVID-19 IgG/M/A enzyme-linked immunosorbent assay kit (SG medical Inc., Seoul, Korea) as screening tests. If 1 or more of these screening test results was positive, 2 additional antibody tests were performed using Abbott Anti-SARS-CoV-2 IgG assay (Abbott, Abbott Park, IL, USA) and cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript USA Inc., Piscataway, NJ, USA). If 2 or more of the total 4 test results were positive, it was determined as positive for the antibody against SARS-CoV-2. RESULTS: According to the criteria of SARS-CoV-2 antibody positivity determination, 12 subjects were determined as positive. The overall positive rate of the SARS-CoV-2 antibody was 0.41% (12/2,935). Of the 12 subjects determined as positive, 7 were diagnosed with COVID-19, and the remaining 5 were nondiagnosed cases of COVID-19. CONCLUSION: In early 2021, the overall seroprevalence of SARS-CoV-2 antibody among HCW located in Daegu was 0.41%, and 0.17% excluding COVID-19 confirmed subjects. These results were not particularly high compared with the general public and were much lower than HCWs in other countries.

Severe Acute Respiratory Syndrome Coronavirus-2 Antibody Responses in Hospitalized Patients with Coronavirus Disease 2019 in Daegu, Korea.

BACKGROUND: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started to spread in Daegu beginning at the end of February 2020. IgG and IgM antibodies against SARS-CoV-2 were measured in hospitalized patients with COVID-19 with moderate to severe symptoms to improve the understanding of antibody responses. METHODS: We enrolled 312 patients with COVID-19 admitted to seven hospitals located in Daegu. Using serum (or plasma) samples from patients with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infections, both IgG and IgM antibodies were measured using commercial enzyme-linked immunosorbent assay (R-FIND CO¬VID-19 ELISA, SG medical, Seoul, Korea). RESULTS: The median value from the initial diagnosis, confirmed by SARS-CoV-2 PCR, to the sampling date was 24 days (day 1 to 88). The total positive rate of IgG was 93.9% and the positive IgM rate was 39.4%, without considering the elapsed period after diagnosis. Positive IgG and IgM rates were highest at 100.0% and 59.0%, respectively, at 3 weeks (15 - 21 days). IgG showed a high positive rate of 79.3% even within 7 days after the initial diag-nosis of the disease and maintained a positive rate of 97.8% until after 8 weeks. CONCLUSIONS: Among hospitalized patients with COVID-19, IgG was detected from the beginning of the diagnosis and persisted for an extended time period.

Inflammatory Markers and Cytokines in Moderate and Critical Cases of COVID-19.

BACKGROUND: Inflammatory responses have been suggested to be associated with coronavirus disease 2019 (COVID-19). This study investigated the inflammatory markers and cytokines in COVID-19 according to its severity. METHODS: We enrolled 49 patients with COVID-19, who were classified as either moderate or critical cases. Serum or plasma interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) levels were measured. RESULTS: Lactate dehydrogenase, ferritin, C-reactive protein, and procalcitonin levels were significantly higher in the critical group than in the moderate group (p < 0.001). IL-6 and TNF-α levels were significantly higher in the critical group, with elevated IL-6 levels from the first to third weeks after confirmed PCR (p < 0.05). CONCLUSIONS: Inflammatory markers and cytokines were increased in COVID-19 and closely related to the severity of the disease. We recommend early active monitoring of IL-6 levels along with inflammatory markers for severe COVID-19.

Comparison of Low Volume and Conventional Sodium Citrate Tubes for Routine Coagulation Testing.

BACKGROUND: Low-volume sample tubes reduce unnecessary blood loss due to repeated blood collection and are more convenient to collect blood from patients with difficult veins. However, different sample tubes may be sources of preanalytical bias, and the corresponding test results may reflect clinically important differences. We compared the new low-volume sodium citrate tube to the conventional sodium citrate tube to determine any significant differences between the two types of tubes for routine coagulation testing. METHODS: We collected blood samples from 48 random patients, who were referred for routine coagulation testing, into low-volume (1 mL) and conventional (2.7 mL) sodium citrate tubes. We assayed the samples for prothrombin time (PT), activated partial thromboplastin time (aPTT), and D-dimer using the automated coagulation analyzer. RESULTS: There was excellent correlation (r > 0.97) between the results of the two tubes for PT, aPTT, and D-dimer. The PT and aPTT for the low-volume sodium citrate tube were significantly shorter than those of the conventional sodium citrate tube. There was no statistically significant difference in the results for D-dimer. The percent biases calculated with Bland-Altman analysis were 0.8% for PT and 2.0% for aPTT. Both of them were within the desirable specifications for bias with 2.0% for PT and 2.3% for aPTT. CONCLUSIONS: It is imperative to perform local validation before introducing new sodium citrate tubes into the routine blood collection practice. Every laboratory needs to standardize the procedures for evaluation of these tubes.

Clinical usefulness of extraction-free PCR assay to detect SARS-CoV-2.

Due to the coronavirus disease 2019 pandemic, the demand for an easily accessible high-throughput screening test is increasing. We aimed to evaluate the usefulness of the extrac-tion-free polymerase chain reaction (PCR) as a screening test to detect severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Real-time reverse transcription PCR was performed in 300 samples (260 SARS-CoV-2 positives and 40 negatives), using both the conventional nucleic acid extraction method (standard method) and the direct method without nucleic acid extraction (direct method). The overall agreement between the standard and direct methods was 86.8 % (kappa 0.60), and the sensitivity of the direct method compared to the standard method was 85.4 %. When the cycle threshold (Ct) value was less than 35, the sensitivity was approximately 90 %-98 %, and when Ct exceeded 35, it decreased to approximately 60 %-65 %. The extraction-free PCR could be useful as a screening test that processes many samples in a short time.

Clinical impact of cell-free serum Epstein-Barr virus status in patients with newly diagnosed malignant lymphoma.

BACKGROUND: We analyzed cell-free serum Epstein‒Barr virus (EBV) DNA to identify its prognostic role in patients with newly diagnosed lymphoma. METHODS: We retrospectively reviewed patients diagnosed with lymphoma between January 2014 and July 2020. Patients were enrolled according to the following criteria: i) pathologically confirmed lymphomas according to the World Health Organization criteria, ii) age over 18 years, iii) serum EBV DNA measurement using polymerase chain reaction prior to first-line therapy, and iv) receipt of curative standard chemotherapy. In total, 263 patients met these criteria and were included in this study. RESULTS: Serum EBV DNA was detected in 79 patients (30.0%). Patients with positive serum EBV tended to be older (P =0.090), and the proportion of T-cell lineage lymphomas was higher than that of B-cell lymphomas (P =0.003). EBV positivity was significantly associated with more advanced disease based on the Ann Arbor staging system (P =0.008) and the International Prognostic Index (P =0.009). EBV positivity was also associated with higher disease relapse (P =0.038) and death rates (P =0.005). EBV-positive lymphomas further showed inferior long-term survival outcomes in terms of progression-free survival (PFS) (P=0.053) and overall survival (OS) (P=0.014). In the subgroup analyses, serum EBV positivity was a significant prognostic factor for patients with B-cell lineage lymphomas in terms of PFS (P =0.003) and OS (P=0.033). CONCLUSION: We demonstrated that cell-free serum EBV DNA status at the time of diagnosis has potential as a prognostic biomarker for patients with newly diagnosed malignant lymphomas.

Characterization of the novel DQA1*01:01:09 allele by next-generation sequencing.

HLA-DQA1*01:01:09 differs from HLA-DQA1*01:01:01:01 by one nucleotide substitution in codon-12 in exon 1.

[FLT3 Gene Mutations as a Prognostic Factor for Acute Myeloid Leukemia.].

BACKGROUND: Two distinct types of fms-like tyrosine kinase 3 (FLT3) gene mutations have been identified in acute myeloid leukemia (AML): D835 and internal tandem duplication (ITD) mutations. These mutations are known to cause the proliferation of leukemic cells and inhibit the apoptosis of leukemic cells due to ligand-independent activation of their receptors. Therefore, the current study attempted to investigate the frequency of FLT3 gene mutations and their prognostic implications for AML in terms of treatment response, survival, and relapse. METHODS: Polymerase chain reaction (PCR) was performed to detect D835 and ITD mutations in 84 newly diagnosed AML patients from February 2001 to October 2004. Restriction fragment length polymorphism (RFLP) and direct sequencing were performed to analyze the D835 mutations. The results were examined based on a comparison with previously known prognostic factors, and the treatment outcomes analyzed according to the existence of the mutations in relation to the event free survival (EFS), overall survival (OS), and complete remission (CR) rates. RESULTS: D835 and IDT mutations were detected in 4.7% (4/84) and 19.0% (16/84), respectively, of the AML patients. The FLT3 gene mutations were not found to be associated with previously known prognostic factors, such as the WBC count, age, and cytogenetic risk group, but were associated with the lactate dehydrogenase levels. The EFS and OS rates were also significantly lower in the FLT3 gene mutation group, especially in AML with normal karyotypes. CONCLUSIONS: FLT3 gene mutations were observed in 23.8% of AML patients and appeared to have a prognostic implication on patient survival. Accordingly, the presence of FLT3 gene mutations, which could be tested easily by using PCR/RFLP methods, should be investigated routinely at the time of diagnosis.

[Two cases of heparin-induced thrombocytopenia diagnosed by particle gel immunoassay.].

Heparin-induced thrombocytopenia (HIT) is a serious complication of heparin therapy. It represents initially as thrombocytopenia and is associated with venous or arterial thrombosis. It has been reported that platelet factor 4/heparin complex antibody plays an important role in the pathogenesis of HIT. Patients on hemodialysis have a high risk of developing HIT because heparin is administrated in hemodialysis as anticoagulant. Thrombocytopenia usually occurs 5 to 10 days after the onset of administration, but occasionally, it may occur rapidly in patients who have preformed antibodies from recent heparin use. We report here 2 cases of HIT with platelet factor 4-heparin reactive antibody in hemodialysis patients.

Identification of a novel mutation in the EYA1 gene in a Korean family with branchio-oto-renal (BOR) syndrome.

The branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by the association of branchial cysts or fistulae, external ear malformation and/or preauricular pits, hearing loss, and renal anomalies. Mutations in the EYA1 gene on the chromosome band 8q13.3, the human homologue of the Drosophila eyes absent (eya) gene, have been identified to be the underlying genetic defects of the syndrome. We found a Korean family with BOR syndrome and identified a novel insertion mutation (c.1474_1475insC; R492PfsX40) in the EYA1 gene. To the best of our knowledge, this is the first report of genetically confirmed case of BOR syndrome in Korea.