Prognostic utility of ADAMTS13 activity for the atypical hemolytic uremic syndrome (aHUS) and comparison of complement serology between aHUS and thrombotic thrombocytopenic purpura

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) involves dysregulation of the complement system, but whether this also occurs in thrombotic thrombocytopenic purpura (TTP) remains unclear. Although these conditions are difficult to differentiate clinically, TTP can be distinguished by low (<10%) ADAMTS13 activity. The aim was to identify the differences in complement activation products between TTP and aHUS and investigate ADAMTS13 activity as a prognostic factor in aHUS. METHODS: We analyzed patients with thrombotic microangiopathy diagnosed as TTP (N=48) or aHUS (N=50), selected from a Korean registry (N=551). Complement activation products in the plasma samples collected from the patients prior to treatment and in 40 healthy controls were measured by ELISA. RESULTS: The levels of generalized (C3a), alternate (factor Bb), and terminal (C5a and C5b-9) markers were significantly higher (all P<0.01) in the patients than in the healthy controls. Only the factor Bb levels significantly differed (P=0.008) between the two disease groups. In aHUS patients, high normal ADAMTS13 activity (≥77%) was associated with improved treatment response (OR, 6.769; 95% CI, 1.605–28.542; P=0.005), remission (OR, 6.000; 95% CI, 1.693–21.262; P=0.004), exacerbation (OR, 0.242; 95% CI, 0.064–0.916; P=0.031), and disease-associated mortality rates (OR, 0.155; 95% CI, 0.029–0.813; P=0.017). CONCLUSION: These data suggest that complement biomarkers, except factor Bb, are similarly activated in TTP and aHUS patients, and ADAMTS13 activity can predict the treatment response and outcome in aHUS patients.

The 2016 WHO versus 2008 WHO Criteria for the Diagnosis of Chronic Myelomonocytic Leukemia

The 2016 WHO diagnostic criteria for chronic myelomonocytic leukemia (CMML) require both absolute and relative monocytosis (≥1×10⁹/L and ≥10% of white blood cell counts) in peripheral blood. Moreover, myeloproliferative neoplasm (MPN) features in bone marrow and/or MPN-associated mutations tend to support MPN with monocytosis rather than CMML. We assessed the impact of the 2016 WHO criteria on CMML diagnosis, compared with the 2008 WHO criteria, through a retrospective review of the medical records of 38 CMML patients diagnosed according to the 2008 WHO classification. Application of the 2016 WHO criteria resulted in the exclusion of three (8%) patients who did not fulfill the relative monocytosis criterion and eight (21%) patients with an MPN-associated mutation. These 11 patients formed the 2016 WHO others group; the remaining 27 formed the 2016 WHO CMML group. The significant difference in the platelet count and monocyte percentage between the two groups indicated that the 2016 WHO criteria lead to a more homogenous and improved definition of CMML compared with the 2008 WHO criteria, which may have led to over-diagnosis of CMML. More widespread use of molecular tests and more sophisticated clinical and morphological evaluations are necessary to diagnose CMML accurately.

A case of atypical hemolytic uremic syndrome associated with the c.1273C>T mutation in the complement C3 gene

No abstract available.

Assessment of Cell Viability in Umbilical Cord Blood by Using 7-AAD/annexin V Dual Staining

BACKGROUND: The quality of cord blood largely depends on cell viability. Viability assessments using trypan blue or 7-aminoactinomycin (7-AAD) staining, which are commonly used methods, may not reflect early apoptosis of cord blood cells. We aimed to investigate early apoptosis in cord blood cells following elapsed time after collection using double staining with annexin V and 7-AAD and to compare the result with that of viability evaluation using trypan blue or 7-AAD staining. METHODS: Umbilical cord blood samples were obtained from 30 pregnant women at the time of delivery between July 2012 and March 2013. Viability of cord blood cells was determined at 0 (T0), 24, and 48 hr after collection by using trypan blue exclusion assay, 7-AAD staining, and 7-AAD/annexin V staining. RESULTS: Viabilities defined by 7-AAD/annexin V staining at T0, 24, and 48 hr after collection were respectively as follows: total nucleated cells, 92.8+/-4.5%, 78.4+/-7.8%, and 65.5+/-8.1%; mononuclear cells, 94.4+/-1.7%, 90.8+/-4.2%, and 84.2+/-6.7%; and CD34-positive cells, 92.4+/-3.0%, 90.7+/-4.7%, and 89.3+/-7.0%. The viability using trypan blue was more than 90% until 48 hr after collection. CONCLUSIONS: The mean viability of total nucleated cells using 7-AAD/annexin V staining decreased to less than 80% at 24 hr after collection; however, the viability of CD34-positive cells was more than 85% until 48 hr. Our study's data will provide useful information for the assessing the quality of cord blood products.

Current routine practice and clinico-pathological characteristics associated with acute promyelocytic leukemia in Korea

BACKGROUND: Acute promyelocytic leukemia (APL) can be life threatening, necessitating emergency therapy with prompt diagnosis by morphologic findings, immunophenotyping, cytogenetic analysis, or molecular studies. This study aimed to assess the current routine practices in APL and the clinico-pathologic features of APL. METHODS: We reviewed the medical records of 48 Korean patients (25 men, 23 women; median age, 51 (20-80) years) diagnosed with APL in 5 university hospitals between March 2007 and February 2012. RESULTS: The WBC count at diagnosis and platelet count varied from 0.4 to 81.0 (median 2.0)x10(9)/L and 2.7 to 124.0 (median 54.5)x10(9)/L, respectively. The median values for prothrombin time and activated partial thromboplastin time were 14.7 (11.3-44.1) s and 29 (24-62) s, respectively. All but 2 patients (96%) showed a fibrin/fibrinogen degradation product value of >20 microg/mL. The D-dimer median value was 5,000 (686-55,630) ng/mL. The t(15;17)(q22;q12 and PML-RARA fusion was found in all patients by chromosome analysis and/or multiplex reverse transcriptase-polymerase chain reaction (RT-PCR), with turnaround times of 8 (2-19) d and 7 (2-13) d, respectively. All patients received induction chemotherapy: all-trans retinoic acid (ATRA) alone (N=11, 26%), ATRA+idarubicin (N=25, 58%), ATRA+cytarabine (N=3, 7%), ATRA+idarubicin+cytarabine (N=4, 9%). CONCLUSION: Since APL is a medical emergency and an accurate diagnosis is a prerequisite for prompt treatment, laboratory support to implement faster diagnostic tools to confirm the presence of PML-RARA is required.

Current routine practice and clinico-pathological characteristics associated with acute promyelocytic leukemia in Korea

BACKGROUND: Acute promyelocytic leukemia (APL) can be life threatening, necessitating emergency therapy with prompt diagnosis by morphologic findings, immunophenotyping, cytogenetic analysis, or molecular studies. This study aimed to assess the current routine practices in APL and the clinico-pathologic features of APL. METHODS: We reviewed the medical records of 48 Korean patients (25 men, 23 women; median age, 51 (20-80) years) diagnosed with APL in 5 university hospitals between March 2007 and February 2012. RESULTS: The WBC count at diagnosis and platelet count varied from 0.4 to 81.0 (median 2.0)x10(9)/L and 2.7 to 124.0 (median 54.5)x10(9)/L, respectively. The median values for prothrombin time and activated partial thromboplastin time were 14.7 (11.3-44.1) s and 29 (24-62) s, respectively. All but 2 patients (96%) showed a fibrin/fibrinogen degradation product value of >20 microg/mL. The D-dimer median value was 5,000 (686-55,630) ng/mL. The t(15;17)(q22;q12 and PML-RARA fusion was found in all patients by chromosome analysis and/or multiplex reverse transcriptase-polymerase chain reaction (RT-PCR), with turnaround times of 8 (2-19) d and 7 (2-13) d, respectively. All patients received induction chemotherapy: all-trans retinoic acid (ATRA) alone (N=11, 26%), ATRA+idarubicin (N=25, 58%), ATRA+cytarabine (N=3, 7%), ATRA+idarubicin+cytarabine (N=4, 9%). CONCLUSION: Since APL is a medical emergency and an accurate diagnosis is a prerequisite for prompt treatment, laboratory support to implement faster diagnostic tools to confirm the presence of PML-RARA is required.

Characterization of anti-factor VIII antibody in a patient with acquired hemophilia A

Acquired hemophilia A (AHA) is a bleeding disorder caused by the development of an auto-antibody against endogenous factor VIII (FVIII). In this study, the epitope of the autoantibody was identified in a 67-year-old female patient with AHA. A prolonged activated partial thromboplastin time (77.4 s) that failed to correct in an incubation mixing test (68.2 s), a decreased FVIII activity, and a high FVIII inhibitor (14.6 Bethesda units/mL) were observed. Enzyme-linked immunosorbent assay demonstrated that the antibody belonged to the immunoglobulin G4 subclass. An immunoblotting assay revealed the light chain (A3/C1/C2 domain) of FVIII as the binding region of the antibody. The bleeding experienced by our patient resulted from the interference of FVIII binding to both FIX by anti-A3 antibodies and phospholipids and von Willebrand factor by anti-C2 antibodies. To the best of our knowledge, this is the first study in Korea characterizing an autoantibody in the context of AHA.

Characterization of anti-factor VIII antibody in a patient with acquired hemophilia A

Acquired hemophilia A (AHA) is a bleeding disorder caused by the development of an auto-antibody against endogenous factor VIII (FVIII). In this study, the epitope of the autoantibody was identified in a 67-year-old female patient with AHA. A prolonged activated partial thromboplastin time (77.4 s) that failed to correct in an incubation mixing test (68.2 s), a decreased FVIII activity, and a high FVIII inhibitor (14.6 Bethesda units/mL) were observed. Enzyme-linked immunosorbent assay demonstrated that the antibody belonged to the immunoglobulin G4 subclass. An immunoblotting assay revealed the light chain (A3/C1/C2 domain) of FVIII as the binding region of the antibody. The bleeding experienced by our patient resulted from the interference of FVIII binding to both FIX by anti-A3 antibodies and phospholipids and von Willebrand factor by anti-C2 antibodies. To the best of our knowledge, this is the first study in Korea characterizing an autoantibody in the context of AHA.

A case of transfusion-related acute lung injury induced by anti-human leukocyte antigen antibodies in acute leukemia / 대한혈액학회지

Transfusion-related acute lung injury (TRALI) is a noncardiogenic pulmonary edema that occurs during or within 6 hours after transfusion. Risk factors for TRALI, which is relatively common in critically ill patients, include recent surgery, hematologic malignancy, and sepsis. Here, we report a case of TRALI induced by anti-human leukocyte antigen (anti-HLA) class II antibodies (HLA-DR) occurring after transfusion of platelet concentrates in a patient with acute leukemia. Although most patients with TRALI show improvement within 48-96 hours, our patient's condition rapidly worsened, and he did not respond to supportive treatment. TRALI is a relatively common and serious adverse transfusion reaction that requires prompt diagnosis and management.

Multiplex PCR for Rapid Detection of Genes Encoding Class A Carbapenemases

In recent years, there have been increasing reports of KPC-producing Klebsiella pneumoniae in Korea. The modified Hodge test can be used as a phenotypic screening test for class A carbapenamase (CAC)-producing clinical isolates; however, it does not distinguish between carbapenemase types. The confirmation of type of CAC is important to ensure optimal therapy and to prevent transmission. This study applied a novel multiplex PCR assay to detect and differentiate CAC genes in a single reaction. Four primer pairs were designed to amplify fragments encoding 4 CAC families (SME, IMI/NMC-A, KPC, and GES). The multiplex PCR detected all genes tested for 4 CAC families that could be differentiated by fragment size according to gene type. This multiplex PCR offers a simple and useful approach for detecting and distinguishing CAC genes in carbapenem-resistant strains that are metallo-beta-lactamase nonproducers.

A Trp33Arg Mutation at Exon 1 of the MYH9 Gene in a Korean Patient with May-Hegglin Anomaly

In this report, we describe a Korean patient with May-Hegglin anomaly from a mutation of the MYH9 gene. The proband was a 21-year-old man with thrombocytopenia. He did not have a bleeding tendency. His neutrophil count was normal at 7490/mm3; however, the neutrophils contained abnormal basophilic inclusions in their cytoplasm. The platelet count was decreased at 15000/mm3 with giant platelets. Coagulation test results were not remarkable. Direct sequencing of MYH9 revealed that he was heterozygous for a mutation in exon 1, which was a 97T>A substitution mutation affecting codon 33, substituting tryptophan with arginine (Trp33Arg). Family study showed that both of his parents had normal phenotype and genotypes, indicating a de novo occurrence of the mutation in the proband.

Characterization of antiphospholipid antibodies in chronic hepatitis B infection / 대한혈액학회지

BACKGROUND: Many infections are associated with antiphospholipid antibodies (aPLs). The purpose of this study was to investigate the prevalence, persistence, clinical significance, and characteristics of aPLs in hepatitis B virus (HBV)-infected patients. METHODS: This study included 143 patients with HBV infection and 32 healthy individuals as controls. The presence of anticardiolipin antibodies (aCL Ab), anti-beta2-glycoprotein I antibodies (beta2GPI Ab), and lupus anticoagulant (LA) was assessed. RESULTS: The total prevalence of aPLs in HBV-infected patients was 12.6% (18 of 143). Of these 18 patients, 15 had low to medium titers of aCL Ab (10 with IgM, 4 with IgG, and 1 with both isotypes). beta2GPI Ab and LA were detected in 3 (2.1%) and 2 (1.4%) patients with HBV infection, respectively. In follow-up specimens from 14 patients with elevated levels of aCL Ab or beta2GPI Ab, 10 (71.4%) showed the persistent presence of aPLs. No clinical manifestations related to aPLs were identified. CONCLUSION: In HBV-infected patients, the most frequently detected antiphospholipid antibodies were IgM aCL Ab, which have a weak association with the clinical manifestations of APS. Unlike the transient presence reported for other infection-associated aPLs, most aPLs were persistently detected over a 12-week period in patients with HBV infection.

The Evaluation of Integrated Test as an Antenatal Screening Test for Down's Syndrome in Korea

BACKGROUND: Antenatal screening for Down's syndrome has been developed and improved over the past 20 yr. Recently, integrated test, which combines the first and second trimester markers has shown the highest detection rate (DR) and lowest false positive rate (FPR) among Down's syndrome screening tests currently in use. The purposes of this study were to evaluate the screening performance of integrated test and to compare the results with triple test studies in Korea. METHODS: The study population consisted of Korean pregnant women who underwent triple or integrated test between April 2005 and December 2008. Triple test was performed using measurements of alpha-fetoprotein (AFP), unconjugated estriol (uE3), and human chorionic gonadotropin (hCG) in the second trimester. Integrated test was performed using nuchal translucency (NT) by ultrasonography and pregnancy-associated plasma protein A (PAPP-A) from maternal serum in the first trimester, and AFP, uE3, hCG, and inhibin-A in the second trimester. The screening performance of each test was evaluated by DR and FPR. RESULTS: Twenty-seven Down's syndrome pregnancies were confirmed in women screened by triple (N=6,736) or integrated test (N=7,688). At 1:100, 1:270, and 1:300 of risk cutoff, triple test showed 45%, 73%, and 73% of DR and 4.7%, 11.2%, and 12.4% of FPR, respectively. At 1:100, 1:150, and 1:300 of risk cutoff, integrated test showed 63%, 69%, and 75% of DR and 1.5%, 1.9%, and 3.0% of FPR, respectively. CONCLUSIONS: Integrated test showed higher DR and lower FPR, demonstrating better screening performance than triple test.

Assessment of Cell Viability in Umbilical Cord Blood before Cryopreservation / 대한수혈학회지

BACKGROUND: The viability of cord blood is an important measure of product quality. Trypan blue (TB) stain is the most commonly and conveniently used method to measure the viability of the cord blood. Recently, cytometric analysis using 7-Aminoactinomycin D (7-AAD) was introduced. Staining with 7-AAD is more sensitive in detecting cellular damage than staining with TB. In addition to this, 7-AAD allows specific measurement of the viability of total nucleated cells (TNC), mononuclear cells (MNC) and CD34+ cells. In this study, we compared the viability of TNC between the TB and 7-AAD method, as well as analyzing the viability of each cell population. METHODS: From February to July 2010, 102 cord blood units were collected and assessed for the viability of TNC by the TB and 7-AAD methods. The viability of mononuclear cells (MNC) and CD34+ cells was assessed by 7-AAD method. RESULTS: The TB and 7-AAD methods were used to assess the viability of TNC, which was 90.1+/-5.7% and 68.4+/-8.0%, respectively. The viability of MNC and CD34+ cells measured by the 7-AAD method was 91.8+/-4.3% and 93.4+/-5.1%, respectively. CONCLUSION: The TNC viability of 7-AAD method was significantly lower than that of TB method. In 7-AAD method, the viabilities of MNC and CD34+ cells were significantly higher than that of TNC. As those are important prognostic factors and measures for successful engraftment after the transplantation, the measurement of the viabilities of MNC and CD34+ cells by 7-AAD method would be helpful to the quality control of the cord blood product.

Clathrin Assembly Lymphoid Myeloid Leukemia-AF10-positive Acute Leukemias: A Report of 2 Cases with a Review of the Literature / 대한진단검사의학회지

The translocation t(10;11)(p13;q14q21) has been found to be recurrent in acute lymphoblastic and myeloid leukemias, and results in the fusion of the clathrin assembly lymphoid myeloid leukemia (CALM) gene with the AF10 gene; these genes are present on chromosomes 11 and 10, respectively. Because the CALM-AF10 rearrangement is a rare chromosomal abnormality, it is not included in routine molecular tests for acute leukemia. Here, we describe the cases of 2 patients with the CALM-AF10 fusion gene. The first patient (case 1) was diagnosed with T-cell ALL, and the second patient (case 2) was diagnosed with AML. Both patient samples showed expression of the homeobox A gene cluster and the histone methyltransferase hDOT1L, which suggests that they mediate leukemic transformation in CALM-AF10-positive and mixed-lineage leukemia-AF10-positive leukemias. Both patients achieved complete remission after induction chemotherapy. The first patient (case 1) relapsed after double-unit cord blood transplantation; there was no evidence of relapse in the second patient (case 2) after allogenic peripheral blood stem cell transplantation. Since CALM-AF10- positive leukemias have been shown to have poor prognosis with conventional therapy, molecular tests for CALM-AF10 rearrangement would be necessary to detect minimal residual disease during follow-up.

Two Cases of Independent Infection by Leclercia adecarboxylata

Leclercia adecarboxylata is a facultative gram negative bacillus of the Enterobacteriaceae family. It has been previously reported as a rarely isolated opportunistic pathogen, mainly in the form of mixed infection with other organisms. We report two cases of independent infection by L. adecarboxylata. One strain of L. adecarboxylata was isolated from Baker's cyst in an immunocompetent patient and the other strain from dialysate in a patient on continuous ambulatory peritoneal dialysis.

Two Cases of Independent Infection by Leclercia adecarboxylata

Leclercia adecarboxylata is a facultative gram negative bacillus of the Enterobacteriaceae family. It has been previously reported as a rarely isolated opportunistic pathogen, mainly in the form of mixed infection with other organisms. We report two cases of independent infection by L. adecarboxylata. One strain of L. adecarboxylata was isolated from Baker's cyst in an immunocompetent patient and the other strain from dialysate in a patient on continuous ambulatory peritoneal dialysis.

Integrated Test for Screening in Down Syndrome as a Predictor of Adverse Pregnancy Outcomes

PURPOSE: To assess the value of first-trimester pregnancy-associated plasma protein-A (PAPP-A), nuchal translucency (NT) and second-trimester alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin-A in predicting pregnancy complications other than fetal aneuploidy. MATERIALS AND METHODS: A retrospective study in 3,121 singleton pregnancies with integrated testing was performed at Kangnam CHA hospital between January 2005 and December 2006. Baseline characteristics, pregnancy outcomes, and serum marker levels were obtained by review of the medical records. We analyzed the data to identify associations between the integrated screening markers and adverse pregnancy outcomes. Statistical analyses were performed with the SPSS program. RESULTS: In preterm labor and preeclampsia, high AFP, hCG, and inhibin-A levels and low PAPP-A and NT levels were found to be significantly correlated (P<0.05). Elevated second-trimester inhibin- A levels were associated with preeclampsia (odds ratio 2.843), low birth weight (odds ratio 1.446), and preterm labor (odds ratio 1.287), and while decreased first-trimester PAPP-A levels were associated with preeclampsia (odds ratio 0.51) and preterm labor (odds ratio 0.75). CONCLUSION: First- and second-trimester maternal serum markers screening can be used for predicting high-risk pregnancies.

Performance Evaluation of Anti-rubella IgM and IgG Antibodies by Roche Modulddar Analytics E170 / 임상검사와정도관리

BACKGROUND: The tests for the anti-rubella antibodies are important in early pregnancies because the risk of congenital anomaly should be considered depending on the results. We would like to evaluate analytical performance of Roche Modular Analytics E170 (Roche Diagnostics, Mannheim, Germany; E170) for anti-rubella antibodies. METHODS: For the comparison studies, a total of 436 sera from pregnant or fertile women was used for the detection of anti-rubella antibodies by E170 and VIDAS analyzer. The precision of E170 for serum anti-rubella IgM and IgG were also evaluated. RESULTS: In the precision study, within-run and total CV of anti-rubella IgM and IgG were below 5%. In the comparison study, the agreement of E170 with VIDAS was above 90%. CONCLUSIONS: The E170 showed a satisfactory precision for anti-rubella antibodies and a high level of concordance with VIDAS. Therefore, E170 would be useful as a routine immunoassay analyzer for measuring anti-rubella IgM and IgG antibodies.

Antimicrobial Resistance and Occurrence of Virulence Factors in Enterococci Isolated from Patients with Bacteremia and Urinary Tract Infection / 대한임상미생물학회지

BACKGROUND: Enterococci have become increasingly predominant as causative agents of nosocomial infections. Infections due to multi-drug resistant enterococci have drawn increasing attention during the past two decades. The purpose of the present study was to evaluate the occurrence of virulence factors and antimicrobial resistance in enterococci isolated from patients with bacteremia or urinary tract infection. METHODS: A total of 209 strains of enterococi (102 Enterococcus faecalis and 107 E. facium) isolated during 8 months of 2005 were collected from 10 university hospitals in Korea. Disk diffusion susceptibility tests were performed using Mueller-Hinton agar. The antimicrobial resistance genes and virulence factors were determined using PCR. RESULTS: In E. faecalis, the rate of resistance to ciprofloxacin, tetracycline, and quinupristindalfopristin was 27.4%, 83.3%, and 85.2%, respectively; no isolates were resistant to ampicillin, vancomycin, teicoplanin, or linezolid. In E. faecium, the rate of resistance to ampicillin, ciprofloxacin, tetracycline, vancomycin, and teicoplanin was 86.9%, 87.9%, 8.4%, 19.6%, and 6.5%, respectively; no strains were resistant to quinupristin-dalfopristin or linezolid. All the E. faecalis strains tested were found to harbor multiple virulence factors, but E. faecium strains were generally without virulence factors except esp. The prevalence of the esp gene was significantly higher in enterococci isolated from urinary tract infection than in those from bacteremia. CONCLUSION: A similar pattern of resistance to antimicrobial agents and prevalence of virulence factors was observed in both the enterococci isolated from bacteremia and urinary tract infection. Our study indicates that host factors are more likely than bacterial properties to influence the development of bacteremia.