Macrolide Resistance of Mycoplasma pneumoniae and Its Detection Rate by Real-Time PCR in Primary and Tertiary Care Hospitals

BACKGROUND: This study aimed to evaluate the prevalence of Mycoplasma pneumoniae in primary and tertiary care hospitals and its macrolide resistance rate. METHODS: Nasopharyngeal swabs were collected from 195 pediatric patients in primary and tertiary care hospitals from October to November 2010. The AccuPower MP real-time PCR kit (Bioneer, Korea) was used for the detection of M. pneumoniae. Direct amplicon sequencing was performed to detect point mutations conferring resistance to macrolides in the 23S rRNA gene. RESULTS: Among the 195 specimens, 17 (8.7%) were M. pneumoniae positive, and 3 of the strains (17.6%) obtained from these 17 specimens displayed the A2063G mutation in 23S rRNA. Three macrolide-resistant M. pneumoniae isolates were isolated from patients hospitalized at the primary care hospital. The positive rates of M. pneumoniae for the primary and tertiary care hospitals were 12.1% (15/124) and 2.8% (2/71), respectively (P=0.033). CONCLUSIONS: The positive rate of M. pneumoniae in the primary care hospital was higher than that in the tertiary care hospital. Simultaneous detection of M. pneumoniae and macrolide-resistant mutation genes in the 23S rRNA by real-time PCR is needed for rapid diagnosis and therapy of M. pneumoniae infections.

Two Cases of Mycoplasma pneumoniae Pneumonia with A2063G Mutation in the 23S rRNA Gene in Siblings

We describe 2 cases of pneumonia caused by the same macrolide-resistant Mycoplasma pneumoniae in siblings. M. pneumoniae was identified using real-time PCR. Direct sequence analysis of the 23S rRNA gene revealed a point mutation in V domain (A2063G) of the 23S rRNA gene.

Evaluation of the Diagnostic Performance of the AdvanSure TB/NTM Real-Time PCR Kit for Detection of Mycobacteria / 대한임상미생물학회지

BACKGROUND: The AdvanSure TB/NTM real-time PCR kit (AdvanSure) was newly developed in Korea to detect Mycobacterium tuberculosis and nontuberculous mycobacteria (NTM) utilizing a specific primer and TaqMan probe targeting the IS6110 and rpoB genes which are unique to these species. The purpose of the present study was to evaluate the clinical utility of AdvanSure by comparing the results of acid-fast staining, mycobacteria culture, COBAS Amplicor MTB PCR (Amplicor), and AdvanSure. METHODS: A total of 182 specimens (105 respiratory and 77 nonrespiratory specimens) were obtained from 165 patients, and acid fast bacilli (AFB) staining, mycobacteria culture, and Amplicor were performed on all specimens. AdvanSure was also performed on the above specimens using the SLAN real-time PCR detection system. The sensitivity and specificity of AdvanSure were analyzed using AFB staining and culture. RESULTS: Of the 182 specimens, M. tuberculosis was detected in 43 specimens and NTM was detected in 12 specimens according to PCR and/or culture. The sensitivity and specificity of the AdvanSure based on AFB culture were 97.3% (36/37) and 95.5% (127/133) in M. tuberculosis and 75.0% (9/12) and 100% (0/133) in NTM, respectively. CONCLUSION: AdvanSure could be useful for detecting M. tuberculosis and NTM in the clinical laboratory with high sensitivity and specificity.

Comparisons of Bayer ADVIA Centaur BNP Assay with Biosite Triage BNP Assay / 임상검사와정도관리

BACKGROUND: B-type natriuretic peptide (BNP) has been useful as a diagnostic tool to define heart failure. Recently, the BNP assay was used on an automated immunochemistry platform. Studies included precision, analytical correlation between the Biosite Triage BNP assay and Bayer ADVIA Centaur BNP assay. METHODS: Between February 22, 2005 and March 4, 2005, 66 cases were anal-yzed. For the BNP measurement, 3 mL blood samples were collected in plastic tubes containing EDTA. Precision was analyzed with 20 repeat tests in 3 different control levels. RESULTS: The ADVIA Centaur assay had between-run precision (CV) of 3.9%, 3.7%, and 3.7% at BNP concentrations of 41.39, 420.08, and 1671.73 ng/L, respectively. The correlation between the ADVIA Centaur and Triage was as follows: ADVIA Centaur=0.753(Triage)-21.888 ng/L (r=0.94). At a cutoff of 100 ng/L, however, the diagnostic agreement was 89.4%. CONCLUSIONS: The ADVIA Centaur BNP assay is the first commercially available BNP assay using an automated immunochemistry platform. This assay has good analytical and clinical performances and agreement with the Biosite Triage BNP Assay.

A Case of Non-secretory Plasma Cell Leukemia with Complex Chromosomal Abnormalities / 대한혈액학회지

We report a case of non-secretory plasma cell leukemia with complex chromosomal abnormalities including t (11;14)(q13;q32). A 57-year-old man was admitted to hospital due to anemia, thrombocytopenia and renal insufficiency. Bone marrow examination and peripheral blood smear revealed a large number of immature plasma cells with positivity for CD38. Monoclonal gammopathy or abnormal paraproteins were not observed in serum protein electrophoresis and immunofixation. The cytogenetic analysis showed complex chromosomal abnormalities [45, XY, -1, t (11;14)(q13;q32), t (12;17)(p13;q21)]. He was died of adult respiratory distress syndrome on the 6th hospital day.

A Cytogenetic Study of 130 Couples with Recurrent Spontaneous Abortion / 대한임상병리학회지

BACKGROUND: Chromosomal aberration of a couple can lead to recurrent miscarriage and it has been accounted for 2-10% of recurrent spontaneous abortions in the Caucasian population. The purpose of this study is to evaluate the frequency of chromosomal abnormalities in couples having fetal losses. We also attempted to define the relationship of those chromosome rearrangements with the presence or absence of stillborn fetus or malformed live child. METHODS: A total of 130 couples with two or more spontaneous abortions were studied. Chromosome studies were performed on metaphases using standard peripheral lymphocyte culture technique. RESULTS: Ten (7.7%) chromosomal abnormalities were detected, 7 (5.4%) in women and 3 (2.3%) in men. The chance of finding chromosomal abnormality in couples with stillborn fetus or malformed live child was higher than in couples with spontaneous abortions but no other adverse event, but the difference was not statistically significant. CONCLUSIONS: Cytogenetic analysis was indicated in couples with recurrent spontaneous abortions. The chance of chromosomal abnormality in couples with stillborn fetus or malformed live child was higher.