BACKGROUND: A rapid and sensitive surveillance culture has a pivotal role in infection control of methicillinresistant Staphylococcus aureus (MRSA). This study was aimed to compare the performance of MRSASelect (Bio-Rad, France) to that of mannitol salt agar containing 6 microgram/mL of oxacillin (MSA-OX) for detecting MRSA in surveillance cultures. METHOD: From May to June 2006, 86 nasal swabs and 21 sputum specimens were enrolled. All specimens were inoculated onto MRSASelect and MSA-OX, which were incubated for 2 days and 3 days, respectively, and colonies were read daily by a technologist. Pink colonies on MRSASelect and yellow colonies on MSA-OX were examined with Gram stain, Pastorex(R) Staph-plus (Bio-Rad) and mecA-PCR. After the final reading, both media were re-examined by a superviser. RESULTS: Of the 107 specimens cultured, 32 (29.9%) were positive for MRSA. Of these, 27 were detected by both media, one by MSA-OX only, and 4 by re-examination. The day-1 and day-2 sensitivities/specificities of MRSASelect were 78.1%/97.3% and 84.4%/97.3%, respectively, while those of MSA-OX were 53.1%/100% and 78.1%/92.1%, respectively. With MRSASelect, two more positives were detected at day 2, but their incubation was less than 18 hour at day 1. There were six false positive organisms detected: three Enterobacter spp., one Acinectobacter spp., and two coagulase-negative staphylococci (CNS). But, the two CNS grew on MSA-OX only. CONCLUSION: MRSASelect with 1-day incubation showed a sensitivity equivalent to and a specificity better than MSA-OX with 2-day incubation. MRSASelect should be a useful medium for MRSA surveillance when it is read after an incubation of 18-28 hours with the confirmatory Gram stain of screen-positives.
Agar ; Enterobacter ; Infection Control ; Mannitol ; Methicillin Resistance* ; Methicillin-Resistant Staphylococcus aureus* ; Oxacillin ; Sensitivity and Specificity ; Sputum ; Staphylococcus aureus

A 42-yr-old man with hepatitis B virus associated liver cirrhosis was admitted to the emergency room because of multiple seizures, a history of chills and myalgia over the previous 2 weeks, and 3 days of melena. He was febrile with a temperature of 38.0degrees C. There were no symptoms and signs related to the genitourinary system, skin, or joints. Three sets of blood cultures were obtained and oxidase-positive, gram-negative diplococci were detected after 25.9-26.9 hr of incubation in all aerobic vials. The organism was positive for catalase and oxidase, and was identified as Neisseria gonorrhoeae, using a Vitek Neisseria-Haemophilus Identification card (bioMerieux Vitek, Inc., USA). Further, 16S rRNA sequencing of this isolate revealed a 99.9% homology with the published sequence of N. gonorrhoeae strain NCTC 83785 (GenBank Accession No. NR_026079.1). Acute bleeding by variceal rupture seems to be a likely route of introduction of N. gonorrhoeae from the mucosa into the blood. To the best of our knowledge, this is the first case of gonococcal bacteremia in Korea.
Adult ; Bacteremia/complications/*diagnosis/microbiology ; Catalase/metabolism ; Esophageal and Gastric Varices/complications/*diagnosis ; Gastrointestinal Hemorrhage/*etiology ; Gonorrhea/complications/*diagnosis/microbiology ; Humans ; Ligation ; Liver Cirrhosis/diagnosis ; Male ; Neisseria gonorrhoeae/genetics/*isolation & purification ; Oxidoreductases/metabolism ; RNA, Ribosomal, 16S/chemistry/genetics ; Sequence Analysis, DNA

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.
Computer Systems ; DNA, Viral/*blood ; Hepatitis B virus/genetics/*isolation & purification ; Hepatitis B, Chronic/*virology ; Humans ; Polymerase Chain Reaction/*methods ; Reagent Kits, Diagnostic ; Viral Load/*methods

BACKGROUND: We have evaluated the analytical performance of SureStep Flexx (Johnson and Johnson, USA) which can report the plasma equivalent glucose test results and be connected to the hospital information networks, following ISO15197 analytic procedure for glucometer for the first time. METHODS: Adopting the guidelines of ISO15197, we measured the precision of ten glucometers from their repeatability and intermediate precision, and determined the accuracies of the glucometer, comparing to those of GEM Premier 4000 (Instrumentation Laboratory, USA). In addition, the guidelines of CLSI EP9-A2 and EP6-A were applied to correlate between data of glucometer and those of laboratory reference method by TBA-200FR (Toshiba Medical Systems, Japan) and to examine its linearity of glucose concentrations measured by SureStep Flexx. We used the clinical specimens and commercial control materials. RESULTS: Repeatabilities and intermediate precisions of those glucometers were 4.0-7.3%, and 4.3-6.2%, respectively. When glucose levels are under 75 mg/dL, the difference between results of those meters and the reference values were within +/-6 mg/dL. However when glucose levels are over 75 mg/dL, those differences were within +/-12.7%. These results were acceptable for the ISO15197 criteria in all glucose concentrations. The glucose concentrations showed the clinically relevant linearity in the range from 36 mg/dL to 491 mg/dL. Moreover, Error Grid Analysis showed that all glucose results were in "zone A", which means that these values were clinically accurate. CONCLUSIONS: This study showed that SureStep Flexx can provide reliable results for patients and clinicians to manage the diabetes mellitus, satisfying the ISO15197 criteria.
Blood Glucose/*analysis ; Blood Glucose Self-Monitoring/*instrumentation/methods/*standards ; Diabetes Mellitus/blood/diagnosis ; Humans ; Quality Control ; Reference Values ; Reproducibility of Results

BACKGROUND: GenoType(R) MTBDRplus assay (Hain Lifescience, Germany) enables detection of the mutations prevalent in rpoB, katG, and inhA genes and identification of Mycobacterium tuberculosis complex (MTB). We evaluated the performance of the MTBDRplus assay in detecting multidrug resistant M. tuberculosis in sputum specimens by directly comparing it to the performance of conventional drug susceptibility testing (DST) with M. tuberculosis culture isolates. METHODS: From December 2007 to July 2008, 40 patients with acid-fast bacilli (AFB) smear-positive and AFB culture-positive sputa, including 19 patients with rifampin (RIF)- or isoniazid (INH)-resistant MTB isolates, were enrolled. The MTBDRplus assay was performed using DNA extracted from respiratory specimens. DST of the culture isolates was performed using an absolute concentration method. RESULTS: The result of the AFB smear test was +/-1 for 7 specimens, +1 for 8 specimens, +2 for 9 specimens, +3 for 9 specimens, and +4 for 7 specimens. The MTBDRplus assay revealed that 37 of the 40 specimens were positive for an MTB-specific band, 12 specimens were RIF-resistant, and 16 specimens were INH-resistant. The rpoB S531L mutation was detected in 58.3% of the RIF-resistant specimens, and the katG S315T1 and inhA C15T mutations were detected in 56.3% and 31.3% of the INH-resistant specimens, respectively. Compared to the sensitivity and specificity of DST, both sensitivity and specificity of MTBDRplus assay for RIF resistance were 100%, and the corresponding values for INH resistance were 82.4% and 90.0%. Discrepant MTBDRplus assay and DST results were obtained in 3 INH-resistant isolates without mutation and 2 INH-susceptible isolates with katG S315T1 and inhA C15T mutations. CONCLUSIONS: The MTBDRplus assay can be applied for AFB smear-positive specimens with positivity +/- to 4+. The assay was reliable for predicting the RIF resistance of culture isolates, but DST was required for confirming INH resistance.
DNA ; Humans ; Isoniazid ; Mycobacterium ; Mycobacterium tuberculosis ; Rifampin ; Sensitivity and Specificity ; Sputum ; Tuberculosis

BACKGROUND: Differentiation of atypical pathogens is important for community-acquired pneumonia (CAP). In this study, we compared sputum and nasopharyngeal swabs (NPS) for use in detection of Mycoplasma pneumoniae (MP), Chlamydophila pneumoniae (CP), and Legionella pneumophila (LP), using Seeplex PneumoBacter ACE Detection Assay (PneumoBacter; Seegene). METHODS: Sputum and NPS specimens were collected from patients in 15 hospitals. DNA was extracted from sputum using QIAamp DNA Stool Mini Kit (Qiagen) and from NPS using easyMAG (bioMerieux). Both types of specimens were evaluated by multiplex PCR using PneumoBacter. To determine the diagnostic performance of this assay, sputum samples were also tested using BD ProbeTec ET Atypical Pneumonia Assay (APA; Becton Dickinson). RESULTS: Among 217 sputum and NPS, 20 (9.2%), 2 (0.9%), and 0 sputum were positive for MP, LP, and CP, respectively, whereas 8 (3.7%) NPS were positive for MP. The sputum APA test yielded 186, 206, and 204 interpretable results for MP, LP, and CP, respectively. Of these, 21 (11.3%) were positive for MP, 2 (1.0%) were positive for LP, and 0 samples were positive for CP. Compared to APA, the sensitivity and specificity of the sputum assay for MP were 95.2% and 100.0%, respectively, whereas for the NPS assay, these were 38.1% and 93.9%. Sputum testing was more sensitive than NPS testing (P=0.002). For LP and CP diagnosis, PneumoBacter and APA tests agreed 100%. CONCLUSIONS: Specimen type is crucial and sputum is preferred over NPS for simultaneous detection of MP, LP, and CP using multiplex PCR in CAP.
Chlamydophila Infections/diagnosis ; Chlamydophila pneumoniae/*genetics/isolation & purification ; Community-Acquired Infections/*diagnosis ; DNA, Bacterial/analysis/isolation & purification ; Humans ; Legionella pneumophila/*genetics/isolation & purification ; Legionnaires' Disease/diagnosis ; Multiplex Polymerase Chain Reaction ; Mycoplasma pneumoniae/*genetics/isolation & purification ; Nasopharynx/*microbiology ; Pneumonia, Mycoplasma/diagnosis ; Reagent Kits, Diagnostic ; Sputum/*microbiology

Haemophilus influenzae has rarely been implicated as the causative agent of urinary tract infections (UTIs). However, cases of UTIs caused by H. influenza in patients with anatomical or functional urinary tract abnormalities have been steadily reported. We report a case of asymptomatic bacteriuria caused by H. influenzae in a kidney transplant recipient. The patient was a 61-yr-old woman who visited the hospital for a routine follow-up after receiving a kidney transplant from a living-related donor; the patient showed no symptoms. Urine microscopy revealed white blood cell (WBC) count of >30/high power field (HPF). Urine culture on blood agar showed non-hemolytic, tiny, translucent, grayish colonies with satellitism around beta-hemolytic colonies of Staphylococcus epidermidis. The organism in the satellite colonies was identified as H. influenzae by using VITEK Neisseria/Haemophilus Identification Card (bioMerieux, Marcy L'Etoile, France) and found to require both X and V factors for growth. The organism did not produce beta-lactamase. Urine culture performed 1 week later revealed H. influenza again. The patient was not treated with antimicrobials. Urine culture performed using chocolate agar 7 weeks later did not reveal H. influenzae. Since H. influenzae does not grow in the media commonly used for urine culture such as blood agar, the use of these media could lead to underestimation of the true frequency of H. influenzae. If UTI is suspected in a patient with anatomical or functional urinary tract abnormality, chocolate agar should be considered for urine culture.
Agar ; Bacteriuria ; beta-Lactamases ; Cacao ; Female ; Follow-Up Studies ; Haemophilus ; Haemophilus influenzae ; Humans ; Influenza, Human ; Kidney ; Kidney Transplantation ; Leukocytes ; Microscopy ; Staphylococcus epidermidis ; Transplants ; Urinary Tract ; Urinary Tract Infections

Haemophilus influenzae has rarely been implicated as the causative agent of urinary tract infections (UTIs). However, cases of UTIs caused by H. influenza in patients with anatomical or functional urinary tract abnormalities have been steadily reported. We report a case of asymptomatic bacteriuria caused by H. influenzae in a kidney transplant recipient. The patient was a 61-yr-old woman who visited the hospital for a routine follow-up after receiving a kidney transplant from a living-related donor; the patient showed no symptoms. Urine microscopy revealed white blood cell (WBC) count of >30/high power field (HPF). Urine culture on blood agar showed non-hemolytic, tiny, translucent, grayish colonies with satellitism around beta-hemolytic colonies of Staphylococcus epidermidis. The organism in the satellite colonies was identified as H. influenzae by using VITEK Neisseria/Haemophilus Identification Card (bioMerieux, Marcy L'Etoile, France) and found to require both X and V factors for growth. The organism did not produce beta-lactamase. Urine culture performed 1 week later revealed H. influenza again. The patient was not treated with antimicrobials. Urine culture performed using chocolate agar 7 weeks later did not reveal H. influenzae. Since H. influenzae does not grow in the media commonly used for urine culture such as blood agar, the use of these media could lead to underestimation of the true frequency of H. influenzae. If UTI is suspected in a patient with anatomical or functional urinary tract abnormality, chocolate agar should be considered for urine culture.
Agar ; Bacteriuria ; beta-Lactamases ; Cacao ; Female ; Follow-Up Studies ; Haemophilus ; Haemophilus influenzae ; Humans ; Influenza, Human ; Kidney ; Kidney Transplantation ; Leukocytes ; Microscopy ; Staphylococcus epidermidis ; Transplants ; Urinary Tract ; Urinary Tract Infections

Helicobacter cinaedi is an enterohepatic species. It can cause bacteremia, gastroenteritis, and cellulitis, particularly in immunocompromised individuals, such as those with acquired immunodeficiency syndrome, malignancy, or alcoholism. There are no previous reports of H. cinaedi infection in Korea. A 71-yr-old man was admitted to the emergency room because of dyspnea on November 9, 2011. He had undergone splenectomy 3 yr ago because of immune hemolytic anemia. Chest plain radiography revealed bilateral pleural effusion. He developed fever on hospital day (HD) 21. Three sets of blood cultures were taken, and gram-negative spiral bacilli were detected in all aerobic vials. The isolate grew in tiny colonies on chocolate agar after 3-day incubation under microaerophilic conditions. This organism tested positive for catalase and oxidase, and negative for urease. The 16S rRNA gene sequence of this isolate exhibited 99.8% homology with the published sequence of H. cinaedi CCUG 18818T (GenBank accession no. ABQT01000054) and 98.5% homology with the sequence of Helicobacter bilis Hb1T (GenBank accession no. U18766). The patient was empirically treated with piperacillin/tazobactam and levofloxacin, and discharged with improvement on HD 31. To our knowledge, this is the first report of H. cinaedi bacteremia in an asplenic patient. Asplenia appears to be a risk factor for H. cinaedi bacteremia.

The HACEK group of microorganisms is responsible for approximately 3-6% of endocarditis cases and is a major cause of culture-negative endocarditis. Here, we report a case of Haemophilus parainfluenzae infective endocarditis that was diagnosed by direct PCR sequencing of 16S rRNA from resected vegetation. A healthy 26-yr-old man was admitted to the emergency room (ER) on March 27, 2011 because of intermittent high fever. The patient was prescribed cefpodoxime for 5 days at the ER. Six and 11 sets of blood cultures were performed at the ER and in a general ward, respectively, using BACTEC Plus Aerobic/F (Becton-Dickinson, USA) and Lytic Anaerobic/F Plus (BD) together. Echocardiography revealed a large vegetation at the posterior mitral valve leaflet. After performing mitral valvoplasty on hospital day (HD) 11, the vegetation tissue was cultured in thioglycolate broth, blood agar, Brucella agar, and MacConkey agar for 7 days, but no organism was grown. Direct PCR sequencing of 16S rRNA of the tissue revealed the presence of H. parainfluenzae. In the 17 sets of blood cultures, bacterial growth was detected in only 2 aerobic bottles of 5 sets taken at HD 9 after 10-day and 14-day incubation. The organism was identified as H. parainfluenzae by using the VITEK NHI card (bioMerieux, France). Direct PCR sequencing of vegetation could be useful in diagnosing bacterial pathogens in infective endocarditis patients, especially in culture-negative cases.
Agar ; Brucella ; Ceftizoxime ; Echocardiography ; Emergencies ; Endocarditis ; Fever ; Haemophilus ; Haemophilus parainfluenzae ; Humans ; Mitral Valve ; Paramyxoviridae Infections ; Patients' Rooms ; Polymerase Chain Reaction ; Sequence Analysis, RNA