A Novel Powered Nasal Irrigation After Endoscopic Sinus Surgery in Patients With Chronic Rhinosinusitis: A Preliminary Study / 대한이비인후과학회지

Background and Objectives@#We aimed to compare the efficacy of a novel powered irrigation system with that of the manual bottle-squeeze method for postoperative healing after endoscopic sinonasal surgery (ESS).Subjects and Method In this prospective randomized clinical trial, 29 patients were enrolled for nasal irrigation (NI) with either NOSSHA® (Womens Care Co., Ltd.) powered irrigation system (NOSSHA® group, n=14) or manual irrigation (control group, n=15). Objective findings were evaluated using the modified Lund-Kennedy scores. Subjective outcomes were assessed using the total nasal endoscopic score (TNES), total nasal symptom score (TNSS), visual analog scale (VAS), and quality of life (QOL) questionnaires in each group at baseline, and 1, 2, 4, 6, and 8 weeks after ESS. We compared the postoperative changes between both groups. @*Results@#The mean TNES of patients were significantly higher in the NOSSHA® group than in the control group (p=0.015); however, the improvement in TNES was achieved 2 weeks earlier in the NOSSHA® group. The improvement in TNES (p<0.001) and TNSS (p<0.001) was statistically significant in both groups. The improvement in QOL was statistically significant in the NOSSHA® (p<0.001) and control group (p=0.007). The improvement in the TNSS and QOL was earlier in the NOSSHA® group by 4 and 7 weeks, respectively; no early improvement occurred in the NOSSHA® group for the VAS score. @*Conclusion@#We validated the usefulness of postoperative NI using a powered device, which may be useful for patients who cannot tolerate manual NI.

A Case report of MALT lymphoma in parotid gland / 대한두경부종양학회지

Mucosa-associated lymphoid tissue (MALT) lymphoma has specific clinical and pathologic features. The most common site MALT lymphomas is the stomach; however, it can also occur in other organs, such as the salivary glands. MALT lymphoma is rare, but its prognosis is good. A 32-year-old man visited Konyang university hospital with parotid mass. Superficial partial parotidectomy was performed to exclude lymphoid neoplasms. IgH gene rearrangement analysis of the surgical specimen led to the diagnosis of MALT lymphoma. The patient underwent esophagogastroduodenoscopy, positron emission tomography-computed tomography, and whole-body bone scan. Regional or distant metastasis was not observed on staging workup. The patient underwent postoperative radiation therapy, there has been no recurrence of MALT lymphoma to date. Here, we report this rare case of parotid MALT lymphoma that was treated with surgery and postoperative radiation therapy.

Clinical Characteristics and Management of Saccular Cysts: A Single Institute Experience

OBJECTIVES: A saccular cyst is defined as a dilated saccule of the larynx, filled with mucus, and is located between the false vocal cords and the thyroid cartilage. Although this uncommon laryngeal condition is benign in nature, it could lead to dyspnea, stridor, and airway obstruction, depending on its size and location. Furthermore, some saccular cysts have been associated with laryngeal carcinoma. This study aimed to characterize this rather uncommon laryngeal condition to aid in determining the proper management of this pathology. METHODS: Medical records were retrospectively reviewed of all patients with saccular cysts diagnosed and treated between 2006 and 2017 at a tertiary otolaryngologic care center. RESULTS: Seven patients with saccular cysts were identified (male:female=2:5; mean age, 34.1 years); two were pediatric patients. Surgical intervention was performed in all patients by laryngo-microsurgery using CO2 laser. There was no recurrence after the initial surgical treatment. CONCLUSION: Saccular cysts can be managed endoscopically using CO2 laser, without requiring an external approach. Therefore, an endoscopic approach should be actively considered for an optimal treatment outcome.

Infuence of Metabolic Syndrome on Hearing Outcome in Sudden Sensorineural Hearing Loss / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Sudden sensorineural hearing loss (S-SNHL) has been reported to be associated with hypertension, diabetes mellitus, hyperlipidemia, and stroke in previous studies. The purpose of this study was to confrm whether metabolic syndrome (MS) infuences the hearing outcome of S-SNHL in the Korean population. SUBJECTS AND METHOD: We prospectively investigated the clinical variables of 231 cases of S-SNHL from 2010 March to 2014 February. MS was defned according to the National Cholesterol Education Program Adult Treatment Panel III with Asian modifcations. We analyzed and compared the basic and clinical characteristics, the thresholds of pure tone audiometry (PTA), and the hearing outcomes of patients with MS (MS group) and without MS (NMS group). RESULTS: There were no signifcant differences in the basic characteristics and initial hearing thresholds between the MS and NMS groups; on the other hand, there were signifcant differences in all of the clinical values of MS between the two groups. The average thresholds of final PTA for the MS and NMS groups were 52.9±30.9 dB and 40.5±27.2 dB, respectively, with meaningful diversity (p < 0.01). According to Siegel's criteria, the recovery rate of the NMS group (95/159, 59.7%) was signifcantly higher than those of the MS group (29/72, 40.3%). The proportion of recovery within 5 days after starting the treatment was signifcantly higher of the NMS group (37/95, 39.0%) than those of the MS group (4/29, 13.8%) (p < 0.01). CONCLUSION: The hearing outcome of the NMS group was signifcantly better than those of the MS group.

Establishment of Maximum Surgical Blood Order Schedule (MSBOS) and Evaluation of Effective Blood Usage in Major Surgery / 대한수혈학회지

BACKGROUND: For effective blood usage and reduction of unnecessary workload at blood banks, we established the maximum surgical blood order schedule (MSBOS) for major elective surgeries and evaluated indicators, including the rate of returned red blood cells (RBCs). METHODS: During August 2016 and May 2017, MSBOS for neurosurgery, thoracic surgery, orthopedic surgery, and general surgery was established using two formulas: the mean units of transfusion per procedure (MSBOS 1) and the mean units of transfusion in transfused patients per procedure (MSBOS 2). The crossmatch to transfusion (C/T) ratio, transfusion probability, and rate of returned RBCs were calculated and analyzed. RESULTS: Based on MSBOS 1, type and screen can be applied to all elective surgeries of the general surgery department. MSBOS 2 was higher than MSBOS 1 in most surgeries ranging from 1 to 3 units. The C/T ratio and transfusion probability of surgery exhibited similar tendencies, and the general surgery department was over-prescribed compared to the actual transfusion requirement. The rate of returned RBCs was the highest in thoracic surgery (32/101, 32%), and the total number of returned RBC unit was the highest in orthopedic surgery (276 of 1131 units). CONCLUSION: MSBOS 1 was the formula corresponding to the purpose of the maximum blood application protocol. Application of an appropriate MSBOS protocol and concurrent utilization of C/T ratio, probability of transfusion, and rate and number of returned units of RBCs will further aid the efficiency of blood bank resources.

Factors Affecting Hemagglutinations Strength in ABO Blood Group Typing Test Using the Tube Method

BACKGROUND: The ABO blood group typing test (ABO test) is an initial pre-transfusion test based on hemagglutination. Although various factors affect hemagglutination strength, few studies have examined how these factors can be applied in clinical laboratories and their effects on hemagglutination. This study was conducted to analyze the factors affecting hemagglutination strength in the ABO test using a tube method applied in many laboratories. METHODS: We conducted a detailed questionnaire survey of 51 laboratories which use the ABO test with a tube method. We also analyzed the results of the ABO test (cell and serum typing) with 40 specimens using factors affecting hemagglutination at a tube method and applied differently in each laboratory. RESULTS: Each laboratory used various methods to prepare red cell suspensions as specimens or reagents and used different reagent to sample ratios, centrifugation protocols, and shaking test tubes before evaluating hemagglutination strength. By testing various combinations of these factors, direct sampling from the red cell layer of the original specimen was found to have the largest effect on lowering hemagglutination strength in cell typing tests. In serum typing tests, various factors influenced hemagglutination strength, including shaking the tube before analysis and the concentration of a home-made red cell suspension used as a reagent. CONCLUSIONS: To achieve accurate results in the ABO test by the tube method, detailed guidelines that include the factors affecting hemagglutination strength determined in this study should be established.

The Author Reply: Breakpoints of the Mycoplasma Hominis and Ureaplasma Urealyticum

No abstract available.

An Incidental Discovery of Morgagni Hernia in an Elderly Patient Presented with Chronic Dyspepsia / 대한소화기학회지

A Morgagni hernia was first described in 1761 by Giovanni Morgagni. In adults, it is accompanied by gastrointestinal- or respiratory-type symptoms. Herein, we report an 84-year-old woman presented to our hospital with nausea and vomiting. After hospitalization, an X-ray revealed a right diaphragmatic hernia. Based on the results of abdominal computed tomography, duodenoscopy, and upper gastrointestinography (gastrografin), we concluded that her symptoms were caused by Morgagni hernia. Our patient underwent laparoscopic surgery, and shortly thereafter, her symptoms resolved.

Occult HBV among Anti-HBc Alone: Mutation Analysis of an HBV Surface Gene and Pre-S Gene

PURPOSE: The aim of this study is to investigate the molecular characteristics of occult hepatitis B virus (HBV) infection in ‘anti-HBc alone’ subjects. MATERIALS AND METHODS: Twenty-four patients with ‘anti-HBc alone’ and 20 control patients diagnosed with HBV were analyzed regarding S and pre-S gene mutations. All specimens were analyzed for HBs Ag, anti-HBc, and anti-HBs. For specimens with an anti-HBc alone, quantitative analysis of HBV DNA, as well as sequencing and mutation analysis of S and pre-S genes, were performed. RESULTS: A total 24 were analyzed for the S gene, and 14 were analyzed for the pre-S gene through sequencing. A total of 20 control patients were analyzed for S and pre-S gene simultaneously. Nineteen point mutations of the major hydrophilic region were found in six of 24 patients. Among them, three mutations, S114T, P127S/T, M133T, were detected in common. Only one mutation was found in five subjects of the control group; this mutation was not found in the occult HBV infection group, however. Pre-S mutations were detected in 10 patients, and mutations of site aa58–aa100 were detected in 9 patients. A mutation on D114E was simultaneously detected. Although five mutations from the control group were found at the same location (aa58–aa100), no mutations of occult HBV infection were detected. CONCLUSION: The prevalence of occult HBV infection is not low among ‘anti-HBc alone’ subjects. Variable mutations in the S gene and pre-S gene were associated with the occurrence of occult HBV infection. Further larger scale studies are required to determine the significance of newly detected mutations.

Prevalence and Antibiotic Susceptibility of Mycoplasma hominis and Ureaplasma urealyticum in Pregnant Women

Mycoplasma hominis (M. hominis) and Ureaplasma urealyticum (U. urealyticum) are important opportunistic pathogens that cause urogenital infections and complicate pregnancy. The aim of this study was to investigate the prevalence, effects on pregnancy outcomes, and antimicrobial susceptibilities of M. hominis and U. urealyticum. We tested vaginal swabs obtained from 1035 pregnant women for the presence of genital mycoplasmas between June 2009 and May 2014. The laboratory and clinical aspects of genital mycoplasmas infection were reviewed retrospectively, and the identification and antimicrobial susceptibility of genital mycoplasmas were determined using the Mycoplasma IST-2 kit. A total of 571 instances of M. hominis and/or U. urealyticum were detected. Of them, M. hominis was detected in two specimens, whereas U. urealyticum was detected in 472 specimens. The remaining 97 specimens were positive for both M. hominis and U. urealyticum. Preterm deliveries were frequently observed in cases of mixed infection of M. hominis and U. urealyticum, and instances of preterm premature rupture of membrane were often found in cases of U. urealyticum. The rates of non-susceptible isolates to erythromycin, empirical agents for pregnant women, showed increasing trends. In conclusion, the prevalence of M. hominis and/or U. urealyticum infections in pregnant women is high, and the resistance rate of antimicrobial agents tends to increase. Therefore, to maintain a safe pregnancy, it is important to identify the isolates and use appropriate empirical antibiotics immediately.

Septicemia Caused by Neisseria meningitidis With Decreased Ciprofloxacin Susceptibility: The First Case Report in Korea

No abstract available.

Detection of Methicillin-Resistant Staphylococcus aureus in Healthcare Workers Using Real-Time Polymerase Chain Reaction

Healthcare-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have recently become an important issue for healthcare facilities due to high rates of infection, mortality, and high treatment costs. We investigated the frequency of MRSA in healthcare workers (HCWs) via nasal carriage and assessed the performance of the LightCycler(R) MRSA Advanced test. We tested nasal swabs from the anterior nares of participating HCWs at an intensive care unit. Nasal swabs were identified as S. aureus, methicillin-sensitive or methicillin-resistant coagulase-negative staphylococci (MSCoNS or MRCoNS), or MRSA by using conventional culture and the LightCycler(R) MRSA Advanced test. Of the 142 HCWs who participated in this study, only 11 participants (7.8%) were MRSA-positive by conventional culture and MRSA ID, and 24 (16.9%) were positive for mecA by real time polymerase chain reaction (PCR). In terms of diagnostic performance, the LightCycler(R) MRSA Advanced test had a sensitivity of 100%, a specificity of 90.1%, a positive predictive value of 45.8%, and a negative predictive value of 100% compared with conventional culture method. The detection limit of the LightCycler(R) MRSA Advanced test was 103 colony/mL. We concluded that real-time PCR was able to rapidly and sensitively detect MRSA in HCWs. However, MRSA must be confirmed by culture due to false positivity.

The First Korean Case Report of Anti-Gerbich

In this study, we report the first Korean case of an anti-Gerbich (Ge) alloantibody to a high-incidence antigen that belongs to the Ge blood group system. The alloantibody was detected in a middle-aged Korean woman who did not have a history of transfusion. Her blood type was B+, and findings from the antibody screening test revealed 1+ reactivity in all panels except the autocontrol. The cross-matching test showed incompatible results with all 5 packed red blood cells. Additional blood type antigen and antibody tests confirmed the anti-Ge alloantibody. While rare, cases of hemolytic transfusion reaction or hemolytic disease in newborns due to anti-Ge have been recently reported in the literature. Therefore, additional further studies on alloantibodies to high-incidence antigens, including anti-Ge, are necessary in the future.

Utility of Procalcitonin as an Early Diagnostic Marker of Bacteremia in Patients with Acute Fever

PURPOSE: Procalcitonin (PCT) is a current, frequently used marker for severe bacterial infection. The aim of this study was to assess the ability of PCT levels to differentiate bacteremic from nonbacteremic patients with fever. We assessed whether PCT level could be used to accurately rule out a diagnosis of bacteremia. MATERIALS AND METHODS: Serum samples and blood culture were obtained from patients with fever between August 2008 and April 2009. PCT was analyzed using a VIDAS(R) B.R.A.H.M.S PCT assay. We reviewed the final diagnosis and patient histories, including clinical presentation and antibiotic treatment. RESULTS: A total of 300 patients with fevers were enrolled in this study: 58 with bacteremia (positive blood culture) (group I); 137 with local infection (group II); 90 with other diseases (group III); and 15 with fevers of unknown origin (group IV). PCT levels were significantly higher in patients with bacteremia than in those with non-bacteremia (11.9 +/- 25.1 and 2.5 +/- 14.7 ng/mL, respectively, p < 0.001). The sensitivity and specificity were 74.2% and 70.1%, respectively, at a cut-off value of 0.5 ng/mL. A serum PCT level of < 0.4 ng/mL accurately rules out diagnosis of bacteremia. CONCLUSION: In febrile patients, elevated PCT may help predict bacteremia; furthermore, low PCT levels were helpful for ruling out bacteremia as a diagnosis. Therefore, PCT assessment could help physicians limit the number of prescriptions for antibiotics.

Molecular Characteristics of Extended Spectrum beta-Lactamases in Escherichia coli and Klebsiella pneumoniae and the Prevalence of qnr in Extended Spectrum beta-Lactamase Isolates in a Tertiary Care Hospital in Korea

PURPOSE: Extended spectrum beta-lactamases (ESBLs) are cephalosporinases that confer resistance to a wide variety of oxyimino cephalosporins and create serious therapeutic problems. In addition, the quinolone resistance qnr genes are becoming increasingly prevalent in clinical isolates, some of which also produce ESBL. This study was designed to evaluate the occurrence and genotypic distribution of ESBL producing Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) as well as the prevalence and distribution of qnr genes in ESBL-producing isolates in a tertiary care hospital in Korea. MATERIALS AND METHODS: We tested a total of 111 ESBL-producing isolates of E. coli and K. pneumoniae, which were collected at Kyung Hee Medical Center from November 2006 to June 2008. ESBL production was determined by the Clinical and Laboratory Standards Institute (CLSI) ESBL confirmatory test. The cefotaxime and ceftazidime resistance of the ESBL-producers were transferred to azide-resistant E. coli J53 by conjugation. The presence and identity of ESBL and qnr genes were determined by polymerase chain reaction (PCR) and nucleotide sequencing. RESULTS: The prevalence of ESBLs was 17.7% (297/1,680) of E. coli and 26.5% (240/904) of K. pneumoniae in our hospital during the study periods. Of the 111 collected isolates, 69 isolates were E. coli and 42 isolates were K. pneumoniae. The most prevalent ESBL genotype was CTX-M15. Among the ESBL-producing isolates, 4 E. coli (5.8%) and 17 K. pneumoniae (40.5%) contained qnr genes. qnrB4 was the most frequent type in both E. coli and K. pneumoniae. CONCLUSION: CTX-M15 was the most frequently encountered ESBL. In addition, a high prevalence of qnr genes among ESBL-producing K. pneumoniae was identified in this study.

Antimicrobial Resistance of Enterococcal Isolates from Blood and Risk Factors for Vancomycin Resistant Enterococcal Bacteremia in a Tertiary Care University Hospital from 2003 to 2007 / 대한임상미생물학회지

BACKGROUND: In Korea, a sudden increase in vancomycin-resistant enterococci (VRE) infection has been noted since the late 1990s. This study was conducted to describe the antimicrobial resistances of enterococcal blood isolates and to identify risk factors associated with VRE bacteremia in a tertiary care university hospital over a recent five-year period. METHODS: This study was conducted to analyze the antimicrobial susceptibilities of enterococcal blood isolates by year from January 2003 to December 2007. Multivariate logistic regression analysis was used to investigate factors associated with VRE bacteremia. RESULTS: A total of 225 enterococcal strains (44.7% Enterococcus faecalis, 42.4% Enterococcus facium, 5.9% Enterococcus casseliflavus, and 4.7% Enterococcus gallinarum) were detected in blood, 55 of which (21.6%) were resistant to vancomycin. In 2004 and 2005, the resistance rates for vancomycin and teicoplanin (33.3% and 27.3%; 34.4% and 23.0%, respectively) increased. In 2003, 2006, and 2007, the resistance rates for vancomycin and teicoplanin (8.7% and 8.7%; 19.0% and 14.3%; 13.5% and 11.5%, respectively) decreased relative to those of the previous years. When 55 patients with VRE bacteremia were compared with 55 patients with vancomycin-susceptible enterococcal bacteremia using multivariate analysis, E. faecium bacteremia (OR 12.624, P<0.001) and enterococcal bacteremia caused by species other than E. faecium and E. faecalis (OR 21.473, P=0.011) were found to be statistical risk factors. Among several infection control activities, the restricted uses of vancomycin and quinupristin-dalfopristin decreased the vancomycin resistance rate from 27.78% to 15.50% (P=0.0257). CONCLUSION: VRE bacteremia would be effectively controlled via infection control activities based on studies regarding risk factors associated with VRE bacteremia.

Measurement of Inflammatory Cytokines in Patients with Rheumatoid Arthritis / 대한진단검사의학회지

BACKGROUND: Inflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) and interleukin (IL)-6 play an important role in pathophysiology of rheumatoid arthritis (RA). We investigated the possibility whether TNFalpha and IL-6 could be used as an objective marker reflecting treatment response in RA. METHODS: Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and rheumatoid factor (RF) together with TNFalpha and IL-6 were measured in 159 specimens obtained from 95 RA patients. RA patients were divided into pre-treatment, methotrexate (MTX) and non-MTX groups by treatment regimen and into inactive and active groups by disease activity. The agreement between changes in marker levels and treatment response, and the correlation between each marker were analyzed. RESULTS: IL-6 was higher in active than in inactive group of patients in all three different treatment subgroups, but TNFalpha was not different between the two groups. IL-6 showed a better agreement with treatment response (MTX group, K=0.58; non-MTX group, K=0.21) than ESR or CRP, whereas TNFalpha did not show an agreement with treatment response. IL-6 was correlated with both ESR (r=0.22) and CRP (r=0.54), but TNFalpha was correlated only with ESR (r=0.21). CONCLUSIONS: Unlike TNFalpha, IL-6 reflects disease activity of RA and shows a better agreement with treatment response than ESR or CRP, indicating that it has an association with clinical features of RA. Therefore IL-6 could be used as an additional marker in the evaluation of treatment response when markers like ESR or CRP show results discordant from clinical features.

Experience on Identification of Cross-Reactive Group Specificity Performed by Anti-human Globulin Panel Reactive Antibody Tests / 대한진단검사의학회지

BACKGROUND: Panel reactive antibody (PRA) is to screen and identify HLA antibody. Majority of antibody specificities in high-PRA are directed against cross reactive group (CREG). Thus, this study was to know the advantage of identifying CREG specificity and whether antibody specificities are changed according to CREG classification. METHODS: HLA class I antibodies were identified from 159 sera from 108 patients in Asan Medical Center, who had shown more than 5% PRA by anti-human globulin (AHG)-complement-dependent cytotoxicity (CDC). Tail analysis-based computer program was developed to identify specificities, applying both Rodey (R-ABC) and Takemoto (T-ABC) classification. The results were also compared with those obtained when without CREG application (ABC). RESULTS: Among 151 cases in which HLA specificities was identified, the frequency of CREG specificity was 22.5% in R-ABC and 27.2% in T-ABC. Eleven cases showed CREG specificities only in one classification. However, the individual antigen specificities in one hand were all included in the CREG identified in the other hand. CREG specificities in samples with PRA >50% (60%) were more frequently identified than those in samples with PRA < or =50% (9%) (in R-ABC, P<0.0001). Without applying CREG to interpretation, specificity was not identified in 9 cases. CONCLUSIONS: Application of CREG enhanced the rate of antibody identification. Antibody specificities of those cases where CREG specificities were different between Rodey and Takemoto classifications were almost the same when compared at the individual antigen level. Therefore, it was thought that it makes no difference to use any one of these two classifications in interpreting PRA.

Comparison of In-house PCR with Conventional Techniques and Cobas Amplicor M. tuberculosis(TM) Kit for Detection of Mycobacterium tuberculosis

PURPOSE: Polymerase chain reaction (PCR) assay, introduced as a fast and sensitive diagnostic method, is useful in detecting Mycobacterium tuberculosis. The purpose of this study was to evaluate the usefulness of in-house PCR assay in the detection of Mycobacterium tuberculosis by comparing PCR results with conventional diagnostic techniques and Cobas Amplicor M. tuberculosis(TM) kit. MATERIALS and METHODS: We retrospectively assessed the diagnostic yield of in-house PCR method employed for the amplification IS6110 sequences in 2,973 specimens. We also compared in-house PCR with Cobas Amplicor M. tuberculosis(TM) kit in 120 specimens collected from June to July 2006. Routine acid-fast stain (AFS) and culture assay were also performed and analyzed. RESULTS: Of 2,973 cases, 2,832 cases (95.3%) showed consistent results between in house PCR, AFS and culture methods, whereas 141 (4.7%) displayed inconsistent results. The sensitivities, specificities, and positive and negative predictive values of each method were as follows: 77.5%, 99.7%, 95.5%, and 98.0%, respectively for PCR; 49.2%, 100%, 100%, and 95.7%, respectively, for AFS method; and 80.7%, 100%, 100%, and 98.3%, respectively, for culture assay. Consistent results between PCR and Cobas Amplicor M. tuberculosis(TM) kit were shown in 109 cases (90.8%). The sensitivities, specificities, and positive and negative predictive values of each method were as follows: 81.3%, 98.9%, 96.3%, and 93.5% respectively for PCR and 71.9%, 100%, 100%, and 90.7%, respectively, for Cobas Amplicor(TM) kit. CONCLUSION: In-house PCR and Cobas Amplicor(TM) kit show high sensitivity and specificity, and are reliable tests in the diagnosis of tuberculosis.

Performance Evaluation of Abbott RealTime HBV Quantification Kit for HBV Viral Load by Real-Time PCR / 대한진단검사의학회지

BACKGROUND: Hepatitis B virus (HBV) DNA quantification is necessary for starting and monitoring of antiviral therapy in patients with chronic hepatitis B. This study was intended to assess the clinical performance of Abbott RealTime HBV Quantification kit (Abbott Laboratories, USA). METHODS: The performance was evaluated in terms of precision, linearity, detection sensitivity, cross-reactivity, and carry-over. A correlation with the Real-Q HBV Quantification kit (BioSewoom Inc., Korea) was also examined using serum samples from 64 patients diagnosed with chronic hepatitis B and underwent lamivudine therapy in Asan Medical Center. We verified the trueness of the system by comparing the outputs with the assigned values of the BBI panel (BBI Diagnostics, USA). RESULTS: Within-run and between-run coefficients of variation (CV) were 3.56-4.71% and 3.03-4.98%, respectively. Linearity was manifested ranging from 53 to 10(9) copies/mL and the detection sensitivity was verified to be 51 copies/mL. None of hepatitis C virus showed cross-reactivity. No cross-contamination occurred when negative and positive samples were alternatively placed in a row. It showed a good correlation with the Real-Q HBV (r2=0.9609) and the test results for the BBI panel were also well agreed to the assigned values (r2=0.9933). CONCLUSIONS: The performance of Abbott RealTime HBV Quantification kit was excellent; thus, it should be widely used in starting and monitoring of antiviral therapy in Korean patients with chronic hepatitis B.