Incidence of Adverse Reaction to Transfusion in Pediatric Patients / 대한수혈학회지

Background@#Transfusions in pediatrics need to be performed carefully because of various variables, such as the blood volume and immature immune system. As a result, adverse transfusion reactions may appear differently from adults. This study examined the frequency and types of adverse transfusion reactions in pediatric patients. @*Methods@#From January 2018 to December 2021, this study was conducted on 58 children who requested red blood cells, platelets, and plasma blood components from Chungbuk National University Hospital. The frequency and types of adverse transfusion reactions were analyzed retrospectively by reviewing blood transfusion-related medical records and compared with previous studies. @*Results@#Approximately 0.9% of total blood components were transfused into pediatric patients; 1,179 units of blood components were transfused. The number of transfusions for red blood cells, platelets, and plasma was 383, 712, and 84 units, respectively. Among 58 patients, 23 adverse transfusion reactions were observed in 15 (25.9%) patients. Of these, 18 were febrile nonhemolytic transfusion reactions, and five were allergic transfusion reactions. Febrile nonhemolytic transfusion reactions occurred in 66.7% of cases with red blood cells, and allergic transfusion reactions occurred with platelets in 60% of cases. @*Conclusion@#This paper reported the incidence and types of adverse transfusion reactions in pediatric patients. This is expected to be more frequent in pediatric patients than adults, but most of them were relieved by supportive treatment because the symptoms were mild. As the awareness of hemovigilance is still low, it is essential to recognize and deal with adverse transfusion reactions through continuous education.

Clinical utility of chromosomal microarray analysis to detect copy number variants: Experience in a single tertiary hospital

Purpose@#To summarize the results of chromosomal microarray analysis (CMA) for copy number variants (CNVs) detection and clinical utility in a single tertiary hospital. @*Materials and Methods@#We performed CMA in 46 patients over the course of two years. Detected CNVs were classified into five categories according to the American College of Medical Genetics and Genomics guidelines and correlated with clinical manifestations. @*Results@#A total of 31 CNVs were detected in 19 patients, with a median CNV number per patient of two CNVs. Among these, 16 CNVs were classified as pathogenic (n=3) or likely pathogenic (LP) (n=11) or variant of uncertain significance (n=4). The 16p11.2 deletion and 16p13.11 deletion classified as LP were most often detected in 6.5% (3/46), retrospectively. CMA diagnostic yield was 24.3% (9/37 patients) for symptomatic patients. The CNVs results of the commercial newborn screening test using next generation sequencing platforms showed high concordance with CMA results. @*Conclusion@#CMA seems useful as a first-tier test for developmental delay with or without congenital anomalies. However, the classification and interpretation of CMA still remained a challenge. Further research is needed for evidence-based interpretation.

Transfusion Dependency in Patients with Acute Myeloid Leukemia during Induction Chemotherapy / 대한수혈학회지

Background@#Blood transfusion is frequently performed as a supportive therapy during the diagnosis and chemotherapy of acute myeloid leukemia (AML). This study examined the frequency of blood transfusion and analyzed the correlation with the treatment response during induction therapy in patients with AML. @*Methods@#From January 2018 to December 2020, blood transfusion information was collected from 23 patients diagnosed with AML during induction therapy. The frequency and volumes of blood transfusions according to the treatment response were collected and analyzed with the overall survival retrospectively. @*Results@#The blood transfusion was performed in all patients with AML during induction therapy. The transfusion frequency and volumes were a median of five (1∼13) times and nine (2∼27) units for red blood cells, respectively.In the platelets, the median frequency was seven (2∼21) times, and the transfusion volumes were 42 (12∼128) units. At the time of the treatment response evaluation, the transfusion dependence was 0% in morphological complete remission and 20% in the morphological leukemic-free state for both RBC and platelets, and 78% for RBC and 67% for platelets in treatment failure. Although not statistically significant, transfusion independence for more than eight weeks after induction therapy showed a better overall survival (P=0.312). @*Conclusion@#When the treatment response was good, the dependence on blood transfusion decreased. The transfusion frequency is expected to help predict the patient's treatment response and prognosis along with the peripheral blood counts.

Transfusion Dependency in Patients with Acute Myeloid Leukemia during Induction Chemotherapy / 대한수혈학회지

Background@#Blood transfusion is frequently performed as a supportive therapy during the diagnosis and chemotherapy of acute myeloid leukemia (AML). This study examined the frequency of blood transfusion and analyzed the correlation with the treatment response during induction therapy in patients with AML. @*Methods@#From January 2018 to December 2020, blood transfusion information was collected from 23 patients diagnosed with AML during induction therapy. The frequency and volumes of blood transfusions according to the treatment response were collected and analyzed with the overall survival retrospectively. @*Results@#The blood transfusion was performed in all patients with AML during induction therapy. The transfusion frequency and volumes were a median of five (1∼13) times and nine (2∼27) units for red blood cells, respectively.In the platelets, the median frequency was seven (2∼21) times, and the transfusion volumes were 42 (12∼128) units. At the time of the treatment response evaluation, the transfusion dependence was 0% in morphological complete remission and 20% in the morphological leukemic-free state for both RBC and platelets, and 78% for RBC and 67% for platelets in treatment failure. Although not statistically significant, transfusion independence for more than eight weeks after induction therapy showed a better overall survival (P=0.312). @*Conclusion@#When the treatment response was good, the dependence on blood transfusion decreased. The transfusion frequency is expected to help predict the patient's treatment response and prognosis along with the peripheral blood counts.

Clinical utility of chromosomal microarray analysis to detect copy number variants: Experience in a single tertiary hospital

Purpose@#To summarize the results of chromosomal microarray analysis (CMA) for copy number variants (CNVs) detection and clinical utility in a single tertiary hospital. @*Materials and Methods@#We performed CMA in 46 patients over the course of two years. Detected CNVs were classified into five categories according to the American College of Medical Genetics and Genomics guidelines and correlated with clinical manifestations. @*Results@#A total of 31 CNVs were detected in 19 patients, with a median CNV number per patient of two CNVs. Among these, 16 CNVs were classified as pathogenic (n=3) or likely pathogenic (LP) (n=11) or variant of uncertain significance (n=4). The 16p11.2 deletion and 16p13.11 deletion classified as LP were most often detected in 6.5% (3/46), retrospectively. CMA diagnostic yield was 24.3% (9/37 patients) for symptomatic patients. The CNVs results of the commercial newborn screening test using next generation sequencing platforms showed high concordance with CMA results. @*Conclusion@#CMA seems useful as a first-tier test for developmental delay with or without congenital anomalies. However, the classification and interpretation of CMA still remained a challenge. Further research is needed for evidence-based interpretation.

Incidence of Red Blood Cell Alloantibody Formation after Platelet Concentrate Transfusions / 대한수혈학회지

BACKGROUND: In platelets transfusion, alloimmunization against the HLA and HPA antigen present in the white blood cells/platelets of the donor blood occurred. In addition, unexpected red blood cell alloantibodies might be produced by the alloimmunization of red blood cells antigens in the transfused platelet component. Therefore, this study examined the incidence of red blood cell alloantibodies after platelet transfusion. METHODS: From January to December 2018, adult patients who requested platelet concentrates or single donor platelets were enrolled. The results of pre/post-transfusion test, including antibody screening test and antibody identification test, were collected the incidence of red blood cell alloantibody formation was then analyzed, retrospectively. RESULTS: A total of 685 patients received 11,894 units of platelet concentrates and 1,402 units of single donor platelets. The median patient age was 64 years and the number of blood transfusions was 4.1. The amount of transfusion per session was 7.3 units, and the total transfused platelet concentrates was 30.9 units. New red blood cell alloantibodies were detected in 0.9% of all patients, and the identification results were observed as unidentified non-specific antibody in 66.7% and anti-E antibodies in 33.3%. The incidence of alloantibody was proportional to the frequency and amount of platelet transfusion. CONCLUSION: This paper reported the incidence of red blood cell alloantibody after platelet transfusion for the first time in Korea. Although matched platelet concentrates supply may be not practical in terms of cost-effectiveness, it may be useful to recognize the possibility of red blood cell alloimmunization and expand the understanding of extended matching transfusion.

Neutrophil-erythrocyte rosettes in direct antiglobulin test-negative autoimmune hemolytic anemia

No abstract available.

Nocardia abscessus Cutaneous Abscess: A Case Report and Review of the Literature / 대한임상미생물학회지

We describe a cutaneous abscess caused by Nocardia abscessus in a previously healthy woman. A 74-year-old woman presented with recurrent bullae on her left forearm that developed 1 week prior and was initially suspected to be a cutaneous infection with Mycobacteria or Tinea corporis. Histopathologically, the skin lesion formed an abscess. A smear revealed a few branched Gram-positive filamentous microorganisms that formed a creamy white colony on a blood agar plate after incubation for 3 days. The colony tested negative on acid-fast bacilli (AFB) staining, but was positive on modified AFB staining. The isolate was confirmed to be N. abscessus by 16S rRNA sequencing analysis. The isolate was susceptible to trimethoprim-sulfamethoxazole, amikacin, cefotaxime and erythromycin but resistant to penicillin. The patient was treated with clarithromycin but subsequently lost to follow-up. To the best of our knowledge, this is the first report of a human cutaneous infection with N. abscessus in Korea.

Association of CD4+CD25+FoxP3+ regulatory T cells with natural course of childhood chronic immune thrombocytopenic purpura / 소아과

PURPOSE: The purpose of this study was to determine the frequency of CD4+CD25+FoxP3+ regulatory T cells (Treg) in the peripheral blood of patients with childhood chronic immune thrombocytopenic purpura (ITP) exhibiting thrombocytopenia and spontaneous remission. The findings of this study indicate the possibility of predicting spontaneous recovery and pathogenesis of childhood chronic ITP. METHODS: Eleven children with chronic ITP (seven thrombocytopenic and four spontaneous remission cases; mean age, 8.8 years; range, 1.7-14.9 years) were enrolled in this study. Five healthy children and eight healthy adults were included as controls. The frequency of Treg was evaluated by flow cytometry in the peripheral blood. RESULTS: In this study, four patients (36%) achieved spontaneous remission within 2.8 years (mean year; range, 1.0-4.4 years). The frequency of Treg was significantly lower in patients with persisting thrombocytopenia (0.13%+/-0.09%, P<0.05), than that in the patients with spontaneous remission (0.30%+/-0.02%), healthy adults controls (0.55%+/-0.44%), and healthy children controls (0.46%+/-0.26%). A significantly positive correlation was found between the frequency of Treg and the platelet count in children. CONCLUSION: These data suggest that a lower frequency of Treg contributes to the breakdown of self-tolerance, and may form the basis for future development of specific immunomodulatory therapies. Furthermore, Treg frequency has prognostic implication toward the natural course and long-term outcomes of childhood chronic ITP.

Group B Streptococcal Toxic Shock-like Syndrome: A Case Report and Review of the Literature / 대한임상미생물학회지

Toxic shock syndrome is an acute and febrile illness that rapidly progress to shock and multi-organ failure, and it is caused by toxin-producing strains of Staphylococcus aureus or Streptococcus species. Streptococcal toxic shock syndrome (STSS) is usually caused by group A streptococci, but non-group A STSS is rare. In this study, we describe a case of STSS caused by Streptococcus agalactiae(group B streptococci) in a patient with alcoholic liver cirrhosis. At arrival in our hospital, the patient had a decreased mental status with hemorrhagic bullae on four extremities, and he progressed to a fatal outcome within 4 days in spite of antibiotic treatment.

GATA1-positive Acute Megakaryoblastic Leukemia in a 6.9-year-old Patient with Down Syndrome: What is the Prognosis? / 임상소아혈액종양

We describe a very rare case of 6.9-year-old boy with Down syndrome (DS) and a prior history of transient myeloproliferative disorder. He was diagnosed with acute megakaryoblastic leukemia and found to have a novel GATA1 gene mutation, as well as a complex karyotype without recurrent acute myeloid leukemia (AML) aberrations. The patient achieved an early bone marrow response to chemotherapy. However, relapse occurred during treatment, 9 months after the initial diagnosis. Although GATA1 mutations are closely associated with DS-AML, we speculate that factors other than the presence of the GATA1 mutation can affect the overall outcome in older pediatric patients.

GATA1-positive Acute Megakaryoblastic Leukemia in a 6.9-year-old Patient with Down Syndrome: What is the Prognosis? / 임상소아혈액종양

We describe a very rare case of 6.9-year-old boy with Down syndrome (DS) and a prior history of transient myeloproliferative disorder. He was diagnosed with acute megakaryoblastic leukemia and found to have a novel GATA1 gene mutation, as well as a complex karyotype without recurrent acute myeloid leukemia (AML) aberrations. The patient achieved an early bone marrow response to chemotherapy. However, relapse occurred during treatment, 9 months after the initial diagnosis. Although GATA1 mutations are closely associated with DS-AML, we speculate that factors other than the presence of the GATA1 mutation can affect the overall outcome in older pediatric patients.

Direct Detection of Methicillin-Resistant Staphylococcus aureus from Blood Cultures Using Three Non-Molecular Methods: PBP2a Latex Agglutination, PBP2a Rapid Immunochromatographic Assay and MRSA-Chromogenic Medium / 대한임상미생물학회지

BACKGROUND: This study compared three non-molecular methods for the detection of methicillin-resistance directly from blood cultures containing Staphylococcus aureus: penicillin-binding protein (PBP) 2a latex agglutination (LA), PBP2a immunochromatographic assay (ICA) and MRSA chromogenic medium (CM). METHODS: Fifty methicillin-resistant S. aureus (MRSA) and 50 methicillin-susceptible S. aureus (MSSA) were seeded into blood-culture bottles. When isolates returned a positive signal, 5 mL of culture was added to serum separator tubes and centrifuged at 1,300 g for 10 min. The pellets were then used as the inoculum for the PBP2a LA, MRSA-CM and PBP2a ICA. The pure colony was used for PBP2a LA test, additionally. RESULTS: The respective sensitivities and specificities were 98 and 100% for PBP2a ICA, and 100 and 100% for MRSA-CM in direct detection of MRSA from positive blood culture. The results of PBP2a LA test using pure colony were entirely compatible with those by mecA gene PCR but the PBP2a LA test using the pellets directly isolated from positive blood culture showed sometimes ambiguous agglutination; its sensitivity and specificity were 78 and 100%, if ambiguous results were scored as negative, and were 90 and 92%, if ambiguous results were scored as positive, respectively. CONCLUSION: For direct detection of MRSA in positive blood culture, MRSA-CM and PBP2a ICA provided excellent results. The PBP2a LA test using pure colony also gave excellent results but the PBP2a LA test by the direct method using pellet of positive blood culture was slightly less sensitive than the other two methods.

Characterization of Acinetobacter baumannii Co-producing Carbapenemases OXA-23 and OXA-66, and armA 16S Ribosomal RNA Methylase at a University Hospital in South Korea / 대한임상미생물학회지

BACKGROUND: In the present study, the resistance mechanisms against carbapenems and aminoglycosides for 23 strains of multi-drug-resistant Acinetobacter baumannii isolated at a university hospital were investigated. METHODS: The minimal inhibitory concentrations (MICs) were determined via broth microdilution or Etest. The genes encoding OXA-type carbapenemases and 16S rRNA methylase were identified using multiplex PCR, and the amplified products were sequenced. Conjugation experiments were conducted, and an epidemiologic study was performed using enterobacterial repetitive intergenic consensus (ERIC)-PCR. RESULTS: In the isolates, the MICs of the tested aminoglycosides, including arbekacin, were >1024 microg/mL; the MICs of aztreonam, cefepime, ceftazidime, and ciprofloxacin ranged from 64 to 128 microg/mL; and the MICs of carbapenem ranged from 32 to 64 microg/mL, as determined through the broth microdilution test. According to the E-test, the MICs of ampicillin/sulbactam and colistin were 8 and 0.25 to 0.38 microg/mL, respectively. Sequence analysis confirmed that all of the isolates expressed carbapenemases OXA-23 and OXA-66, as well as armA 16S rRNA methylase. In addition, ISAba1 was identified upstream of the gene encoding OXA-23. OXA-23 and armA were not transferred to Escherichia coli J53 cells in the transconjugation experiments. ERIC-PCR molecular fingerprinting produced a single pattern in all cases. CONCLUSION: The co-production of OXA-23 and armA 16S rRNA methylase may be attributed to the multidrug resistance of the A. baumannii isolates in the present study. Stricter surveillance and more rapid detection are necessary to prevent the spread of this type of resistance in the future.

Characterization of a Novel Monoclonal Antibody (27H2) Recognizing Human CD34 Class III Epitope

BACKGROUND: Monoclonal antibodies (mAbs) recognizing Class III epitope of CD34 are essential for flow cytometric diagnosis of leukemia. METHODS: 27H2 mAb was developed from a mouse alternatively immunized with human acute leukemia cell lines, KG1 and Molm-1. Using flow cytometric analysis of various leukemic cell lines and peripheral blood, immunohistochemical study of frozen tonsil, we characterized 27H2 mAb. Antigen immunoprecipitated with 27H2 mAb immunobloted with anti-CD34 mAb. A case of bone marrow sample of acute lymphoblastic leukemia (ALL) patient was obtained at CBNU Hospital. For epitope identification enzyme treatment with neuraminidase and O-sialoglycoprotein endopeptidase (OSGE) and blocking assay with known classIII mAb (HPCA-2) were done. RESULTS: Only KG1 and Molm-1 revealed positive immunoreactivity. Immunohistochemical staining disclosed strong membranous immunoreactivity on high endothelial venules. Antigen immunoprecipitated by 27H2 mAb showed approximately 100 kDa sized band immunoblotted with anti-CD34 under non-reducing conditions. Epitope recognized by 27H2 mAb disclosed resistancy to both neuraminidase and OSGE treatment and completely blocked with known class III mAb preincubation. CD34 positive leukemic cells in BM of pre B cell ALL patient detected by FITC-conjugated 27H2 and HPCA-2 were identified with similar sensitivity. CONCLUSION: A novel murine mAb recognizing class III epitope of human CD34 with high affinity, which is useful for flow cytometric diagnosis of leukemia, was developed.

Evaluation of Cheongmeak DCS(TM) Reagents for Chemistry Analyzers / 임상검사와정도관리

BACKGROUND: The evaluation of newly developed reagents for chemical analyzer is essential for an accurate testing of various samples. We evaluated the analytical performance of the DCS(TM) reagents (Cheongmeak, Korea). METHODS: Fifteen chemistry reagents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), total bilirubin, total protein, albumin, blood urea nitrogen (BUN), creatinine, glucose, calcium, inorganic phosphorus, total cholesterol, triglyceride and HDL-cholesterol were tested for precision, linearity and correlation according to CLSI guidelines in the Hitachi 7180 chemistry analyzer (Hitachi High-Technologies Co., Japan). RESULTS: The coefficients of variation (CV) of both within-run and total precision were below 3.98% for all analytes, which fully meets of CLIA 88 decision ranges. Good linearity was shown for all analytes in measurement ranges. Coefficients of correlation were also good for all analytes. CONCLUSIONS: DCS(TM) reagents showed good precision, linearity and correlation. Therefore, the DCS(TM) reagents could be acceptable for use in routine chemistry analyzers.

Evaluation of Dipicolinic Acid-Based Mueller Hinton Agar Biplate for Detection of IMP-1 and VIM-2 type Metallo-beta-Lactamase in Imipenem Non-susceptible Gram Negative Bacilli / 대한진단검사의학회지

BACKGROUND: Since metallo-beta-lactamase (MBL)-producing isolates can hydrolyze carbapenem and also easily transfer the resistance genes to other bacteria, a rapid and accurate detection of MBL has become very important. We evaluated the utility of Mueller Hinton agar (MHA) biplate containing dipicolinic acid (DPA) as a screening method to detect IMP-1 and VIM-2 type MBL-producing isolates. METHODS: Based on our preliminary tests using various concentrations of DPA, 200 and 300 microg/mL concentration of DPA were chosen for further study. Bacterial lawns were grown on MHA biplate, one half of which contained DPA while the other did not. The inhibition zone around the imipenem (IPM) disk on both sides of this plate was compared. The stability of DPA in the stored DPA-MHA biplate was also evaluated during three months using two MBL- and one non-MBL-producing isolates. RESULTS: When the criterion of a > or =7 mm increase of inhibition zone around the IPM disk on the MHA containing DPA compared to MHA without DPA was used, the sensitivities and specificities were 94.7% and 97.6% for 200 microg/mL DPA-MHA biplate, and 98.2% and 97.6% for 300 microg/mL DPA-MHA biplate, respectively. The activity of the DPA in this biplate was stable for three months. CONCLUSIONS: Assays using DPA 300-MHA biplate were highly sensitive and specific for the detection of IMP-1 and VIM-2 type MBL-producing bacteria. In addition, it is easy to perform; so, it may be useful to apply this method for detection of IMP-1 and VIM-2 type MBL in clinical laboratories.

A Case of Streptococcus salivarius Meningitis in a Patient with Cerebrospinal Fluid Rhinorrhea after Skull Base Fracture / 대한임상미생물학회지

Streptococcus salivarius meningitis is very uncommon, and most cases are iatrogenic, occurring after invasive procedures such as spinal anesthesia or lumbar puncture etc.. Post-traumatic occurrence of this infection is especially rare. A 20-year-old man with a previous history of skull base fracture was seen at the emergency department with signs of acute bacterial meningitis. The CSF had a few gram positive cocci with neutrophilic pleocytosis, which were identified as S. salivarius by the Vitek system (bioMerioux, Inc., Hazelwood, MO, USA), rapid ID 32 Strep (bioMerieux, Marcy-l'Etoile, France) and 16S rRNA sequencing. The microorganism showed intermediate resistance to penicillin (MIC=0.25 microg/mL) but was susceptible to cefotaxime (MIC=0.25 microg/mL) and vancomycin (MIC= 0.75 microg/mL). The patient was treated with ceftriaxone and vancomycin. He also had his CSF leakage repaired by an endoscopic approach. To our knowledge, this is the first case of S. salivarius meningitis reported in Korea.

A Case of Granulicatella adiacens Septicemia Identified by 16S rRNA Sequencing Analysis / 대한임상미생물학회지

Granulicatella adiacens is one of the fastidious gram positive cocci previously described as nutritionally variant streptococci due to their requirement of L-cysteine, pyridoxal, or thiol compounds for growth. These bacteria have been identified as significant causative agents of endocarditis, opthalmic infections, and meningitis. We report a case of septicemia caused by G. adiacens in an 80-year-old patient with cholangiocarcinoma. The organism was identified by phenotypic and 16S rRNA sequencing analyses.

A Case of Catheter-Related Bacteremia by Arthrobacter woluwensis / 대한진단검사의학회지

Arthrobacter woluwensis, a catalase-positive coryneform bacterium recognized as an opportunistic pathogen, was repeatedly isolated from the blood of a 56-year-old male patient with metastatic colon cancer. The isolate was identified by various phenotypic tests and by sequencing analysis of 16S rRNA. Antimicrobial susceptibility testing was performed by E-test; the MICs to vancomcyin, cefotamine, and penicillin were 1.5 microgram/mL, >64 microgram/mL, and 4 microgram/mL, respectively. The patient was treated with vancomycin, and the subclavian catheter, which was presumed to be the source of the infection, was removed. Thereafter, repeated blood cultures did not grow the organism. The infections of human caused by A. woluwensis have not been reported previously in Korea, probably because of the difficulty of identifying Arthrobacter strains by conventional biochemical tests.