Bacterial Endocarditis Caused by Abiotrophia defectiva in a Healthy Adult: A Case Report with Literature Review / 대한임상미생물학회지

Infective endocarditis caused by Abiotrophia defectiva is rarely encountered. A 67-year-old male transferred from a local hospital presented with severe dyspnea and pulmonary edema. Preoperative transthoracic echocardiography revealed severe mitral regurgitation with large vegetation. Blood cultures grew A. defectiva, a gram positive, nutritionally deficient streptococcus variant. Emergent mitral valve replacement through right thoracotomy was performed, and after completing six weeks of antibiotic combination therapy (vancomycin, ampicillin, and gentamicin), the patient recovered fully. Because of the need for prompt surgical treatment and long-term antibiotic therapy and lack of laboratory experience with the organism, physicians and laboratory workers should pay close attention to the possibility of A. defectiva infective endocarditis when gram positive cocci are detected in blood cultures.

Prevalence of Unexpected Antibodies in Pregnant Korean Women and Neonatal Outcomes / 대한수혈학회지

BACKGROUND: In pregnant women, the frequency of irregular antibodies that cause hemolytic disease of the fetus and newborn (HDFN) vary between study populations. The clinical manifestations of HDFN differ according to the specificities and degree of irregular antibodies. This study examined the frequency and nature of maternal alloimmunization and neonatal outcomes. METHODS: Pregnant women, who underwent irregular antibody screening for prenatal testing at an obstetrics clinic in a single center, were enrolled. Those who screened positive for irregular antibodies were selected as the test group, and age- and obstetrics history-matched pregnant women were selected as the control group to evaluate the pregnancy outcomes according to irregular antibodies. RESULTS: The prevalence of irregular antibodies was 2.78% (42/1,508). With the exception of an unidentified antibody, anti-D was the most frequently identified antibody, followed in order by anti-E and anti-Le(a). The rate of fetal death was higher in the test group (6/37, 16.2%) than in the control group (1/37, 2.7%) (P=0.047). Eight pregnant women had anti-C or anti-D, one woman had a stillbirth, and four living neonates developed hyperbilirubinemia. Of six pregnant women with anti-E alone or with other alloantibodies, three experienced a spontaneous abortion or stillbirth. Among the six newborns with maternal anti-Le(a) and anti-Jk(a), four developed hyperbilirubinemia, but their mothers did not experience a spontaneous abortion or stillbirth. CONCLUSION: The prevalence of unexpected antibodies among pregnant Korean women was 2.78%. A significant difference in neonatal outcomes was observed, including the death rate, prematurity, and hyperbilirubinemia, depending on the specificity of the unexpected antibody.

Selection of Unnecessary Urine Culture Specimens Using Sysmex UF-5000 Urine Flow Cytometer / 대한임상미생물학회지

BACKGROUND: Urine culture is one of the most frequently requested tests in microbiology. Automated urine analyzers yield much infection-related information. The Sysmex UF-5000 analyzer (Sysmex, Japan) is a new flow cytometry urine analyzer capable of quantifying urinary particles, including bacteria, WBCs, and yeast-like cells (YLCs) and can provide a Gram stainability flag. In this work, we evaluated how many unnecessary urine cultures could be screened out using the UF-5000. METHODS: We compared the culture results of 126 urine samples among 453 requested urine cultures (from sources other than the Urology and Nephrology departments) with urinalysis results. Urine cultures were considered positive if bacterial or YLC growth was ≥104 CFUs/mL. RESULTS: We used urinalysis cut-off values of 50/µL and 100/µL for bacteria and YLC, respectively. Forty eight of the 126 (38.1%, or 10.6% of 453 requested) cultures were below these cut-off values and did not contain any culture-positive samples. CONCLUSION: Bacteria and YLC counts generated using the UF-5000 analyzer could be used to screen out negative cultures and reduce urine culture volume by ~10% without sacrificing detection of positive cultures.

Analysis of Blood Donors in a Tertiary Care Hospital as a Fixed Collection Site / 대한수혈학회지

BACKGROUND: Blood transfusion is important when treating patients with anemia or bleeding; thus, supply of blood components should be stable prior to transfusion. To recruit donors, blood donation sites should be conveniently located. This study evaluated factors responsible for increased donation rates in hospitals and the characteristics of the donors in hospital blood banks without a fixed blood collection site nearby. METHODS: We retrospectively reviewed 687 blood donations at a blood donation center in Pusan National University Yangsan Hospital (PNUYH) from March 2011 to June 2016. A total of 3,053,695 blood donors listed in the 2014 Korean Red Cross Annual Report were compared to donors in PNUYH. We analyzed the age distribution of donor at blood donation centers from Korean Red Cross according to presence and number of high school and college. RESULTS: Comparison with total blood donors in Korea revealed that there were more blood donors in their thirties, office workers and business owners at PNUYH (P<0.001). The percentage of younger donors in their twenties differed significantly according to the presence of a college within a 4 km radius of the blood donation center (P=0.03). The presence of a high school did not affect the proportion of teenage donors (P=0.833). CONCLUSION: The blood donation rate at our medical institution without fixed blood collection sites nearby increased. A regional hospital may be used as a blood collection site to recruit donors in areas in which there are no fixed blood donation centers.

Experience of Failure Mode and Effect Analysis in Transfusion Medicine / 대한수혈학회지

BACKGROUND: Blood transfusions are complicated procedures, and are highly sensitive to mistakes that could seriously endanger the life of patients. The failure mode and effect analysis (FMEA) can be used to inspect and improve high risk processes. Here, we aimed to identify the risk factors of a blood transfusion process and to improve its safety by optimizing the process. METHODS: We conducted a weekly meeting from March to April 2014. We investigated the frequency of events for 2013 (before FMEA) and 2015 (after FMEA). The FMEA process was performed in eight steps and the improvement priorities were determined in accordance with the magnitude of calculated fatalities (multiplied by severity, occurrence, and detection scores). RESULTS: The whole process of blood transfusion was analyzed by detailed steps: Decision of blood transfusion, blood transfusion request, pre-transfusion test, blood product discharge, delivery, and administration process. Then, we identified the types of failures and likelihood of occurrence, discovery, and severity. Based on the calculated risk priority number, strategies to improve the highest failure modes were developed. Eleven transfusion-related events occurred before FMEA, and three events occurred after FMEA. CONCLUSION: In this study, we analyzed the failure modes that may occur during a transfusion procedure. The FMEA was a useful tool for analyzing and reducing the risks associated with a blood transfusion procedure. Continuous efforts to improve the failure modes would be helpful to further improve the safety of patients undergoing blood transfusion.

Delayed Hemolytic Transfusion Reaction with Alloimmunization of Rh Phenotype: A Two-Case Study / 대한수혈학회지

Delayed hemolytic transfusion reaction is difficult to prevent using an unexpected antibody test performed prior to transfusion, and unlike acute hemolytic transfusion reaction, it occurs a few days after blood transfusion. Hence, determining the reason for delayed hemolytic transfusion reaction may be a tim-consuming task for clinicians Here, we report our experience of two cases of delayed hemolytic transfusion reaction as a result of the unexpected antibody production to Rh blood group antigens after transfusion. The first patient with a history of transfusion during admission was identified as having anti-E and anti-C antibodies according to the antibody identification test at the time of re-admission. The second patient who had chronic blood transfusion due to cancer treatment was found to have anti-C antibody. Both patients received transfusion of Rh antigen-compatible RBC units only after unexpected antibody development. However, like both cases, patients receiving continuous blood transfusion should be considered for a routine Rh phenotype test.

Optimal Phlebotomy Interval to Change Hematocrit Levels in Patients with Polycythemia / 대한수혈학회지

BACKGROUND: Phlebotomy is used to maintain hematocrit levels 4 weeks. RESULTS: No patients with secondary polycythemia and 25.8% of the patients with PV had thrombotic events pre-phlebotomy. Post-phlebotomy, none of the patients experienced a thrombotic event. The average decrease in hematocrit level was significantly different between the three groups, being 1.98±1.90% (4 weeks). CONCLUSION: To prevent thrombotic events, phlebotomy is a safe and effective treatment to reduce hematocrit levels in patients with polycythemia, regardless of medication. For the maximum effect, a <2-week phlebotomy interval to reduce and <4-week phlebotomy interval to maintain hematocrit levels could be effective.

Distribution and Antimicrobial Resistance of Streptococcus pneumoniae at Four University Hospitals in Busan and Gyeongnam / 대한임상미생물학회지

BACKGROUND: Streptococcus pneumoniae is the most common human pathogen causing community-acquired pneumonia. There is little information on the recent antimicrobial susceptibility patterns of S. pneumoniae in Busan and Gyeongnam of Korea. The aim of this study was to investigate the distribution and antimicrobial resistance of S. pneumoniae at 4 university hospitals in Busan and Gyeongnam. METHODS: We collected and analyzed the antimicrobial susceptibility results of 850 S. pneumoniae strains isolated from regional 4 university hospitals during the last 2 years from July 2013 through June 2015. RESULTS: Among 850 S. pneumoniae strains, 635 strains were isolated from respiratory specimens, followed by blood (N=121), CSF (N=13), and others (N=81). Antimicrobial susceptibility rates to penicillin, cefotaxime and ceftriaxone were 79.4%, 76.6% and 83.6%, respectively. The resistant rates to erythromycin and clindamycin were 80.9% and 68.2%, respectively. The resistant rates to levofloxacin were 9.2%. There were some differences in resistant rates by age groups, years, and specimen types. CONCLUSION: We found the changes of antimicrobial resistance of S. pneumoniae during the last 2 years. It is necessary to monitor the antimicrobial susceptibility of S. pneumoniae regularly for empirical therapy and for early detection of the changes of resistance.