A Case of Fungemia with Co-isolation of Candida parapsilosis and Trichosporon asahii Confirmed by MALDI-TOF MS and D2 rRNA Sequencing

Fungi are a major cause of human infections with diverse clinical manifestations. The incidence of fungal infections has increased over time, particularly in patients who have risk factors such as neutropenia, immune suppression, an intravascular catheter, parenteral nutrition, a prosthetic device, and prior broad spectrum antibiotic therapy. Here, we present an unusual case of co-infection by 2 distinct fungi, Candida parapsilosis and Trichosporon asahii, isolated from a patient who did not have any known risk factors initially, except active pulmonary tuberculosis. Despite the negative conversion of sputum acid-fast bacilli (AFB) culture test after treatment, clinical symptoms were refractory to therapy. The patient developed symptoms suggesting septic shock, and 2 distinct colonies were isolated from a blood specimen, which were identified as C. parapsilosis and T. asahii by MALDI-TOF and rRNA sequencing. Fever and hypotension were relieved after anti-fungal agent injection, and pulmonary lesions identified by imaging also improved.

Two Cases of Hypersensitivity Reactions Caused by Human Serum Albumin During Therapeutic Plasma Exchange

Iso-oncotic human serum albumin (HSA) is the primary replacement fluid of choice during therapeutic plasma exchange (TPE). Hypersensitivity reactions to HSA are rare, but require proper evaluation and management. In this article, we report two cases of hypersensitivity reactions to 5% HSA during TPE and discuss strategies to address this problem. The first case was a 60-year-old female patient, who was scheduled for TPE for treatment of recurrent focal segmental glomerulosclerosis after ABO-incompatible kidney transplantation. She developed a pruritic rash on her entire body during the first two sessions of TPE using 5% HSA. The third session was conducted using 500 mL normal saline, 1,000 mL 10% pentastarch, and 750 mL 5% HSA, where she eventually developed a pruritic rash when HSA was infused. There were no adverse events during the fourth and fifth session when fresh frozen plasma was used in place of HSA. The second case was a 50-year-old male patient diagnosed with optic neuritis, who was admitted for five sessions of TPE. The patient developed a pruritic rash on his entire body during the first session of TPE using 5% HSA. The patient experienced no adverse events during the following four sessions using fresh frozen plasma. Certain elements contained in HSA, such as albumin aggregates, prekallikrein activator, and caprylate-modified albumin, might be the reason for these hypersensitivity reactions. Careful selection of alternative replacement fluids is important to avoid premature termination of TPE procedures and secure optimal treatment options for patients.

Frequency of Red Blood Cell Antigens According to Parent Ethnicity in Korea Using Molecular Typing

Frequencies of red blood cell (RBC) blood group antigens differ by ethnicity. Since the number of immigrants is increasing in Korea, RBC antigens should be assessed in children/youths with parents of different ethnicities to ensure safe transfusions. We investigated the frequency of RBC antigens, except for ABO and RhD, in 382 children and youths with parents having Korean and non-Korean ethnicities. Subjects were divided into those with ethnically Korean parents (Korean group; N=252) and those with at least one parent of non-Korean ethnicity (non-Korean group; N=130). The 37 RBC antigens were genotyped using the ID CORE XT system (Progenika Biopharma-Grifols, Bizkaia, Spain). The frequencies of the Rh (E, C, e, hr(S), and hr(B)), Duffy (Fy(a)), MNS (Mi(a)), and Cartwright (Yt(b)) antigens differed significantly between the two groups. Eight and 11 subjects in the Korean and non-Korean groups, respectively, exhibited negative expression of high-frequency antigens, whereas 14 subjects in the non-Korean group showed positive expression of low-frequency antigens. The frequency of RBC antigens has altered alongside demographic changes in Korea and might lead to changes in distribution of RBC antibodies that cause acute or delayed hemolytic transfusion reaction.

The Role of the Signal-to-Cutoff Ratio in Automated Anti-HCV Chemiluminescent Immunoassays by Referring to the Nucleic Acid Amplification Test and the Recombinant Immunoblot Assay

BACKGROUND: Following discontinuation of the recombinant immunoblot assay (RIBA), the only available supplementary test for the detection of hepatitis C virus (HCV) is the nucleic acid amplification test (NAAT). However, the NAAT does not adequately detect past HCV. Consequently, it is hard to distinguish between past HCV infection and biological false positivity with an anti-HCV result alone. We assessed the diagnostic performance of two immunoassays: the ARCHITECT anti-HCV chemiluminescent microparticle immunoassay (CMIA; Abbott Diagnostics, Wiesbaden, Germany) and the Access HCV Ab PLUS chemiluminescent immunoassay (CIA; Bio-Rad, Marnes-la-Coquette, France). We also explored an optimized algorithm to determine the anti-HCV results. METHODS: We tested 126,919 patients and 44,556 individuals who underwent a medical checkup. RIBA and NAAT were conducted for samples that tested anti-HCV-positive using CMIA and CIA. We assessed the optimal signal-to-cutoff (S/CO) ratio in HCV-positive samples. RESULTS: In total, 1,035 blood samples tested anti-HCV-positive. Of these, RIBA was positive in 512, indeterminate in 160, and negative in 363 samples. One hundred sixty-five samples were NAAT-positive. Diagnostic sensitivity and positive predictive value (PPV) were 96.7% and 52.1%, respectively, for CMIA, and 94.7% and 72.3%, respectively, for CIA. The optimal S/CO ratio was 5.2 for CMIA and 2.6 for CIA at 95% PPV. In total, 286 samples tested positive in CMIA and 444 in CIA, while 443 samples tested positive in both assays. CONCLUSIONS: It is hard to determine anti-HCV positivity based on the S/CO ratio alone. However, this study elucidated the role of the S/CO ratio by using the NAAT and RIBA.

The Experience of Applying an Australian Red Blood Cell Safety Stock Calculation to Korean Hospitals / 대한수혈학회지

BACKGROUND: The management of red blood cell inventory in hospital's blood bank is crucial. The Australian Red Cross Blood Service developed a RBC safety stock calculation method (abbreviated as the ‘Australian formula’). In this study, we applied this method to four Korean hospitals to calculate the safe RBC stock level. METHODS: The hospitals included in this study were three tertiary teaching hospitals and one teaching hospital. The number of hospital beds in these hospitals were 1093, 1330, 1400, and 854, respectively. The data were collected from the Korea Blood Inventory Monitoring System of Centers for Disease Control & Prevention. The target/minimal/maximal RBC inventory levels and inventory days (inventory level/average daily usage) by ABO blood types were calculated using the daily red cell transfusion, wastage, and supply data between May and October 2016. RESULTS: The enrolled hospitals showed different levels for the target/minimal/maximal RBC inventory according to each blood group. The average of RBC inventory days in the four hospitals was 4.2 days. For each blood group, RBC inventory days were 3.2~4.4 days for O blood group type, 3.5~4.7 days for A blood group, 3.9~4.5 days for B blood group, and 3.9~5.5 days for AB blood group. CONCLUSION: Because the optimal RBC inventory levels are different depending on the hospital characteristics and the ABO blood group, it is necessary to set the RBC inventory levels for each hospital distinctly. The data obtained in this study will help manage blood product inventory in various hospital blood banks.

Minimum Specimen Volume Analysis of ABO/RhD Typing and Unexpected Antibody Screening Using an Automated Immunohematology System DAYmate S / 대한수혈학회지

BACKGROUND: Phlebotomy performed for laboratory testing has the potential to cause anemia in newborns and infants. This study investigated the minimum specimen volume required for an automated immunohematology analyzer DAYmate S. METHODS: Three combinations of tubes were evaluated: I. 6 mL EDTA tube, II. 0.5 mL microtainer (on top of 3 mL EDTA tube), and III. 1 mL sample cup (on top of 6 mL EDTA tube). ABO/RhD cell typing was done using centrifuged red cells; unexpected antibody screening was carried out using plasma, and Type & Screening was conducted using whole blood samples. The lowest specimen volume capable of performing 10 repetitive tests without errors was investigated. RESULTS: ABO/RhD cell typing could be performed from I. 30 μL, II. 25 μL, and III. 25 μL. Unexpected antibody screening could be performed from I. 170 μL, II. 150 μL, and III. 140 μL. According to the hematocrit levels, Type & Screening could be performed from 30%, I&III 650 μL, II. 800 μL; 40%, I&III 650 μL, II. 900 μL; and 50%, I&III 1,000 μL, II. Testing using specimen volumes below 1,000 μL was difficult. CONCLUSION: By separating red cells and plasma, pre-transfusion testing of ABO/RhD cell typing and unexpected antibody screening could be conducted with very small specimen volumes using DAYmate S compared to Type & Screening using whole blood. The application of small-sized sample tubes was more competitive and this is expected to be very useful for preventing iatrogenic anemia in neonates and infants less than 4 months old.

Clinical Significance of Anti-G Alloantibody and Serologic Interpretation Strategies for Patients with an Anti-C+D Pattern: First Report of Anti-G Alloantibody Identification in Korea

No abstract available.

A Case of Anti-JMH Antibody with High-Titer, Low-Avidity Characteristics: The First Case in Korea / 대한수혈학회지

Anti-John Milton Hagen (JMH) is a high-titer, low-avidity (HTLA) antibody against the high frequency red blood cell (RBC) antigen JMH. It occurs very rarely and has not yet been reported in Korea. Here, we report a case of anti-JMH antibody identified in a 92-year-old man without previous blood transfusion history, who had been hospitalized with pneumonia. The patient's hemoglobin level was reduced to 7.6 g/dL on the 35th day of hospitalization, requiring RBC transfusion. Antibody identification test revealed antibodies that showed pan-reactivity to all panel cells at the antiglobulin phase. A titration test confirmed that it was a HTLA antibody. He was given one least-incompatible unit of RBC without any adverse events, and his hemoglobin level increased to 9.3 g/dL. The patient's sample was referred to a reference laboratory and the antibody was identified as anti-JMH. He was successfully transfused with 6 additional units of least-incompatible RBCs without complication. HTLA antibodies against high frequency antigens, such as anti-JMH, are less likely to cause significant destruction of transfused antigen positive RBCs. However, identifying the specificity of these antibodies is necessary to appropriately understanding the clinical significance of the antibody, detecting other clinically important alloantibodies that may coexist, and determining the appropriate blood for transfusion.

Strategies to Prevent Transfusion-Transmitted Infection in Blood Centers / 대한수혈학회지

There has been continuous effort to prevent transfusion-transmitted infection (TTI). Strategies to prevent TTI can be divided into two components: first, determining donor eligibility, and second, managing bacterial contamination of blood products. To determine donor eligibility, medical history taking and screening tests for infectious diseases should be performed. To prevent bacterial contamination, blood collection process should be aseptic, tests for bacterial detection should be performed, and an application of pathogen reduction technology should also be considered. In this review, screening test items and methods, including nucleic acid amplification tests for determining donor eligibility, and precautions for blood collection, bacterial detection methods, and pathogen reduction technology for the prevention of bacterial contamination of blood products were discussed in detail.

The Change in Distribution of Red Blood Cell Antigens in Korean Youth: In an Era of Multicultural Society / 대한수혈학회지

BACKGROUND: It is important to check the blood group antigens to ensure the safety of blood transfusions. Recently, the number of multicultural families and foreigners has increased in Korea; therefore, a survey for red blood cell antigens for multicultural families is need. We performed a phenotyping of their red blood cell antigens and found the characteristics in providing basic data. METHODS: We recruited young people under the age of 26 years from multicultural family between September 2015 and March 2016. The participants were divided into two groups: the multicultural youth group (MCY) and the non-multicultural youth group (non-MCY). Subjects underwent phenotyping of ABO, Rh, Kell, Kidd, Duffy, MNS, and Diego blood group, and the results were compared and characterized between the two groups. RESULTS: A total of 226 subjects (89 MCY, 137 non-MCY) were recruited. The blood groups with differences between MCY and non-MCY were E, e in Rh and S in MNS. In MCY, the frequency of CDe expression in the Rh blood group was higher and the cDE expression was lower. There were 3.4% and 2.2% of MCY with no expression of Fy(a) and s, respectively, which were rare blood types in Koreans. CONCLUSION: The difference in frequency of red blood cell antigens between MCY and non-MCY have been identified. These results suggest that the national blood policy reflects an increasing number of multicultural families and Korea needs to be prepared for a population change.

Utilization Analysis of Neonatal Red Blood Cell Aliquots and Development of Electronic Issuing System / 대한수혈학회지

BACKGROUND: Although transfusion in neonates needs to be strictly regulated due to the vulnerability of neonates, there is lack of systematic studies and the working process is not well-established. This study was aimed to point out the problems of current status and to improve the efficiency of systems used in blood aliquots for neonatal transfusions. METHODS: Total red blood cell (RBC) aliquots were analyzed between May 2009 and January 2016 in the neonate intensive care unit. We investigated the aliquot number, issued day interval from the first issued aliquot among the post-aliquots, patients' blood type, and discarded RBC units among the requested RBC units. RESULTS: Of the 472 RBC aliquots, 95.4% (450/472) were divided into two units. The distribution of patients' blood type was similar to that of the Korean population, in decreasing order: A blood group (34.3%), B group (28.2%), and O group (27.5%). The second, third, and forth units of post-aliquots were taken after an average of 49.9 (0∼617.9) hours. Among the post-aliquots, the number of units discarded without use was 22.5%. CONCLUSION: According to the evaluation of current status for neonatal transfusions, we should use aliquot RBC properly and reduce unnecessary requests for aliquot RBC. In addition, in order to reduce the number of near misses, we propose a new label to be attached on the aliquotted blood bags and suggest a development of electronic blood issuing system.

MALDI-TOF MS: Its Application in the Clinical Laboratory and a Paradigm Shift in Clinical Microbiology

In the past decade, clinical microbiology underwent revolutionary changes in methods used to identify microorganisms, a transition from slow and traditional microbial identification algorithms to rapid molecular methods and mass spectrometry (MS). Earlier, MS was clinically used as a highly complex method that was adapted for protein-centered analysis of samples in chemistry laboratories. Recently, a paradigm-shift happened when matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) MS was implemented to be used in microbiology laboratories for rapid and robust methods for accurate microbial identification. Two instrument platforms, marketed by well-established manufacturers, are beginning to displace automated phenotypic identification instruments and in some cases even genetic sequence-based identification practices. This review summarizes the current role of MALDI-TOF MS in clinical research, in diagnostic clinical microbiology laboratories, and serves as an introduction to MALDI-TOF MS, highlighting research associated with sample preparation, algorithms, interpretations, and limitations. Currently available MALDI-TOF MS instruments as well as software platforms that support the use of MALDI-TOF with direct specimens have been discussed in this review. Finally, clinical laboratories are consistently striving to extend the potential of these new methods, often in partnership with developmental scientists, resulting in novel technologies, such as MALDI-TOF MS, which could shape and define the diagnostic landscape for years to come.

Probability of Obtaining Specific Antigen-Negative Blood Units through Antigen Testing in Korean Medical Institutes / 대한수혈학회지

BACKGROUND: When unexpected antibodies are identified, selection for specific antigen-negative blood units is needed in order to ensure transfusion safety. We estimated the number of blood units required for antigen testing to obtain specific antigen-negative units in Korean medical institutes. METHODS: We analyzed cases of selection for specific antigen-negative units for recipients who had antibodies identified in Seoul National University Bundang hospital from January 2008 to December 2010 and cases entered into the KRBP (Korean Rare Blood Program) online database from July 2013 to February 2014 from eight medical institutes. RESULTS: A total of 559 cases of 266 patients were analyzed. The antigen types requiring two units on average for one specific antigen-negative unit were E, P1, and Lea. Three units on average were required for one Fyb-negative blood unit, four units for one Jka-negative unit, four units for one Jkb-negative unit, 4.5 units for one Leb-negative unit, five units for one C-negative unit, six units for one M-negative unit, and seven units for one S-negative unit. In cases of obtaining specific antigen-negative units for more than one antigen type, three units on average were required for one E, c-negative unit and seven units for one C, e-negative unit. Other multiple antigen-negative units required up to 20 units. CONCLUSION: The accurate antigen-negative frequency in the Korean population should be investigated. Following this effort, the number of blood units required for selection of specific antigen-negative units could be predicted and practical measures for obtaining specific antigen-negative blood units could be suggested for Korean medical institutes.

Frequency of CD36 Deficiency on Platelets and Monocytes in Koreans / 대한수혈학회지

BACKGROUND: CD36 deficiency was first identified in a patient who showed refractoriness to HLA-matched platelet transfusion. CD36 deficiency can be divided into two subgroups. The type I phenotype is characterized by platelets and monocytes exhibiting CD36 deficiency. The type II phenotype lacks surface expression of CD36 in platelets only. In this study, the frequency of type I and type II CD36 deficiency in Koreans was evaluated. METHODS: A total of 220 samples were randomly selected from subjects who requested CBC testing from August 2013 to February 2014. The expression levels of CD36 on platelets and monocytes were analyzed by flow cytometry using FITC-conjugated CD36 antibodies. Correlation between the median fluorescence intensity of CD36 and the number of platelets or monocytes was evaluated using Pearson's correlation coefficient. RESULTS: Type I phenotype, lacking CD36 on platelets and monocytes, was present in 0.9% and type II, lacking CD36 on platelets, was present in 3.2%. The median fluorescence intensity of CD36 did not show correlation with the count of platelets or monocytes. CONCLUSION: Type I subjects may produce alloantibodies against CD36 following transfusion or pregnancy, leading to refractoriness to HLA-matched platelet transfusion, post-transfusion purpura, or neonatal immune thrombocytopenia. Studies to determine exact frequency of CD36 deficiency in Koreans, including a larger population, should be conducted, and more case reports on patients immunized against CD36 are also needed in order to elucidate the clinical importance and relevance of CD36 deficiency testing and the transfusion of CD36-deficient platelets.

Genotyping for RhD and RhCEce Antigens Using Free Circulating Nucleic Acids in Plasma and Serum / 대한수혈학회지

BACKGROUND: The Rh blood group includes several antigens, of which D, C, E, c, and e are clinically important. Although nucleic acids from whole blood can be used for Rh blood group genotyping, it is also possible to genotype free circulating fetal nucleic acids from plasma and serum. We performed Rh blood group phenotyping and genotyping using nucleic acids from whole blood and free circulating nucleic acids from plasma and serum, respectively. The results were compared. METHODS: Forty-four blood samples were phenotyped and genotyped for RhD and RhCE blood groups. Phenotyping was performed by hemagglutination assay. Further tests were performed on RhD-negative samples. Nucleic acids were extracted from whole blood, plasma, and serum. Plasma and serum were prepared after filtration and genotyped by real-time polymerase chain reaction. RESULTS: RhD blood group results showed one (2.3%) discrepant case in which the DEL phenotype appeared wild RHD genotype. Among nucleic acids, there were seven discrepant results: two from plasma and five from serum based on whole blood nucleic acids. RhCE blood group results showed three (6.8%) phenotype-genotype discordances. Among nucleic acids, seven (15.9%mpared to phenotypes. Kappa coefficients of serum were lower than those of plasma. CONCLUSION: RHD and RHCE genotype could be identified by assaying free circulating nucleic acids in plasma or serum. This study suggests that plasma is more reliable than serum as a specimen for RHD and RHCE genotyping of free circulating nucleic acids.

The Current Status of Management for Specific Antigen-negative Blood Units in Korea / 대한수혈학회지

BACKGROUND: For pretransfusion testing, ABO and D antigen tests along with unexpected antibody screening tests are performed. When unexpected antibodies are identified, selection for specific antigen-negative blood units is needed in order to ensure safety of transfusion. METHODS: A questionnaire survey was conducted from August 23 to September 10, 2012 in 36 medical institutes in order to evaluate the current status of management for specific antigen-negative blood units in Korea. The questionnaire consisted of a method for detection of unexpected antibodies, the number of antibodies identified in the last year, and the antigen tests performed for specific antigen-negative blood units. For the institutes where blood donations are obtained, we asked about the enrollment of donors for specific antigen-negative or rare blood types. RESULTS: Among the 36 institutes, antigen testing for specific antigen-negative blood units was performed in 20 institutes. Of the remaining 15 institutes, except for one institute which answered as not applicable, eight institutes requested blood units at blood centers and another seven institutes replaced antigen tests with crossmatching tests. Among the 21 institutes where blood donations are obtained, two institutes had enrolled donors for specific antigen-negative or rare blood types. CONCLUSION: For selection of specific antigen-negative blood units for recipients who have identified antibodies, standardization of antibody detection tests and antigen tests is needed. In addition, the accurate antigen frequency in the Korean population should be investigated and donors for specific antigen-negative or rare blood types should be enrolled and managed systematically. Following these efforts, practical measures for obtaining specific antigennegative blood units could be suggested for medical institutes in Korea.

Adoption of Donor Screening Policy in a Tissue Bank at a Tertiary Hospital / 대한수혈학회지

BACKGROUND: Tissues for transplantation can save lives or restore essential functions. According to national policies and regulations, access to suitable transplantation, as well as the level of safety, quality, efficacy of donation, and transplantation of tissues, differ significantly between countries. We reviewed a few guidelines on tissue banking from the aspect of screening tests. In addition, four-year experience with screening panels for donated bones and donors at a tertiary hospital is introduced. METHODS: Seven national and international guidelines for screening tests for donors and donated tissues were reviewed. At our institution, screening tests for donation involve two steps. At retrieval, the first screening panel, including ABO/Rh typing, unexpected antibody screening, VDRL, HBsAg, anti-HBs, anti-HBc IgM, anti-HCV, anti-HIV, and microbiological cultures was performed. The second screening panel, including the same tests, except culture studies, was performed after 90 days. From 2008 to 2011, a total of 245 retrievals of bone tissue were performed and the screening panel results were analyzed. RESULTS: Mandatory screening serologic tests for living donors can differ according to local law or regulation and/or screening for endemic diseases. At our institution, among 245 donated bones for a period of four years, 61 bone tissues were discarded due to noncompliance for the second screening (n=32), contamination or no culture study results (n=9), abnormal serologic test results (n=8), and so on. CONCLUSION: Donor screening policies for tissue banking are various according to national laws or endemic disease status. Second screening tests with consideration of the window period should be adopted.

Human Platelet Antigen Genotyping Using a Multiplex Single-Base Primer Extension Reaction in Koreans / 대한수혈학회지

BACKGROUND: Alloimmunization of human platelet antigens (HPA) is associated with clinically significant disease, such as platelet refractoriness, neonatal alloimmune thrombocytopenia, or posttransfusion purpura. It is determined by single nucleotide polymorphism of genes for platelet membrane glycoprotein. To date, approximately 27 HPAs have been discovered, and their frequencies differ depending on ethnicity and country. METHODS: We conducted an investigation of prevalence of HPA in the Korean population using a multiplex single-base primer extension reaction (SNaPshot). With 84 specimens from healthy donors, HPA genotyping was performed on 11 different HPAs, including HPA-1, -2, -3, -4, -5, -6, -7, -8, -9, -13, and -15. RESULTS: A total of 90 blood samples were genotyped. The genotype frequencies of HPA were as follows: HPA-1a/1a: 100.0%, -2a/2a: 83.3%, -2a/2b: 14.3%, -2b/2b: 2.4%, -3a/3a: 39.3%, -3a/3b: 52.4%, -3b/3b: 8.3%, -4a/4a: 100.0%, -5a/5a: 95.2%, -5a/5b: 4.8%, -6a/6a: 94.0%, -6a/6b: 6.0%, -7a/7a: 100.0%, -8a/8a: 100.0%, -9a/9a: 97.6%, -9a/9b: 2.4%, -13a/13a: 100.0%, -15a/15a: 23.8%, -15a/15b: 51.2%, and -15b/15b: 25.0%. CONCLUSION: The SNaPshot assay was employed for detection of SNPs in various clinically significant HPA genes. In addition to well-known frequencies of previously reported HPA-1 to -8, this study showed frequencies of HPA-9, -13, and -15 in Koreans for the first time. The SNaPshot technique might be suitable for use in actual clinical testing in patients with platelet alloimmunization.

Analysis of Xenotropic Murine Leukemia Virus-Related Virus (XMRV) in Korean Blood Donors in a Medical Center / 대한수혈학회지

BACKGROUND: Xenotropic murine leukemia virus-related virus (XMRV) has been detected in peripheral blood mononuclear cells (PBMNs), therefore, it has been regarded as being infectious and transmittable by transfusion. Thus, we attempted to detect XMRV in blood samples in order to confirm the absence of XMRV from blood donors. METHODS: We achieved 165 blood donors and four chronic fatigue syndrome (CFS) patients. We performed real-time polymerase chain reaction using the LightCycler 480 (Roche, Penzberg, Germany) for the gag and env genes of the XMRV genome. DNA was extracted from peripheral blood samples. We used Uracil-N-Glycosylase in order to prevent contamination and DNA extracted from mouse embryonic fibroblasts (MEF) for amplification control. RESULTS: No XMRV was detected in any of the blood donors in both the gag and env genes. In four CFS patients, amplification was not detected in the gag gene. In two of four CFS patients, amplifications were detected and the melting temperature was in agreement with that of MEF control in the env gene. CONCLUSION: Although XMRV was not present in blood samples from blood donors, this is the first report on XMRV in Korean blood donors. We confirmed the absence of XMRV in Korean blood donors, the same as studies reported in other countries.

A Case of Imported Plasmodium malariae Malaria

Malaria, the most common vector-borne parasite infection worldwide, results from infection by Plasmodium species. Approximately 80% of malaria cases are caused by P. vivax, which is broadly distributed from tropical to temperate regions; P. falciparum is the second most common infectious species. P. malariae and P. ovale are responsible for a relatively small proportion of malaria cases. Here, we report the case of a 23-yr-old Korean woman who acquired a P. malariae infection while visiting the Republic of Ghana in West Africa for business. She was diagnosed with P. malariae malaria on the basis of peripheral blood smear (PBS) and species-specific conventional and real-time PCR assays for 18S rRNA. She was treated with hydroxychloroquine, and the resulting PBS examination on day 2 suggested that negative conversion occurred. At her 1-month follow-up, however, both the PBS examination and molecular test for malaria demonstrated recurrent parasitemia. We started rescue therapy with mefloquine, and the patient recovered successfully. This is an important finding suggesting possible late recrudescence of a chloroquine-resistant P. malariae strain identified not only by its morphological features, but also by molecular tests.