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Background: In the public cord blood (CB) banks, only safe CB units with adequate cell doses are processed and stored. Complete blood count (CBC) of CB is crucial for estimating total nucleated cells (TNC) and screening suitable CB units without hematologic abnormalities. We analyzed CBC parameters of the donated CB from healthy Korean neonates to establish CBC reference values., Methods: A total of 2,129 Korean CB units, donated and processed during the period from August 2007 to December 2007, were enrolled. We measured hemoglobin (Hb), white blood cell (WBC) count, differential count of WBC, platelets and nucleated red blood cell (nRBC) count by XE-2100 automated hematology analyzer (Sysmex, Japan), and estimated reference value of each parameter by using parametric (Mean+/-2SD) and/or non-parametric methods (2.5-97.5 percentile). And also, we compared the result of each parameter in relation to sex of neonates and delivery method., Results: Because the differences of CBC values among different subgroups were not remarkable, we established the reference intervals as follows without subgroup division: Hb, 9.0-14.4 g/dL; WBC count, 5.6-18.5 x 10(3)/microL; differential count of WBC (neutrophils, 40.8-72.4%; lymphocytes, 17.2-46.7%; monocytes, 4.9-12.8%; eosinophils, 0.7-7.0%; basophils, 0.0-1.6%); platelet, 130-287 x 10(3)/microL; nRBCs, 0.0-13.1/100 WBC., Conclusions: We established cord blood CBC reference values of healthy Korean neonates using a large-scale CB units. The established CBC reference values from our study will be useful as basic data for CBC interpretation and assessment of transplant suitability of donated CB.

Background: We evaluated the performance and false positive rate of Mediace RPR test (Sekisui, Japan), a newly introduced nontreponemal test using a chemistry autoanalyzer., Methods: The sensitivity of Mediace RPR test was analyzed using sera from 50 patients with syphilis in different stages (8 primary, 7 secondary, and 35 latent), 14 sera positive with fluorescent treponemal antibody absorption (FTA-ABS) IgM, and 74 sera positive with conventional rapid plasma regain (RPR) card test (Asan, Korea) and also positive with Treponema pallidum hemagglutination (TPHA) test or FTA-ABS IgG test. The specificity was analyzed on 108 healthy blood donors. We also performed RPR card test on 302 sera that had been tested positive with Mediace RPR test and also performed TPHA or FTA-ABS IgG test to analyze the false positive rate of Mediace RPR test. A cutoff value of 0.5 R.U. (RPR unit) was used for Mediace RPR test., Results: Mediace RPR test on syphilitic sera of different stages (primary, secondary, and latent stages) and FTA-ABS IgM positive sera showed a sensitivity of 100%, 100%, 82.9% and 100%, respectively. Among the 74 sera positive with conventional RPR card test and TPHA or FTA-ABS IgG test, 55 were positive with Mediace test. The specificity of Mediace RPR test on blood donors was 97.2%. Among the 302 sera positive with Mediace RPR test, 137 sera (45.4%) were negative by RPR card and TPHA/FTA-ABS IgG tests., Conclusions: Although the sensitivities of Mediace RPR were good for primary and secondary syphilis, due to its high negative rate of Mediace RPR over the conventional RPR positive samples, further studies are necessary whether it can replace conventional nontreponemal test for screening purpose. Moreover, in view of the high false positive rate, positive results by Mediace RPR test should be confirmed with treponemal tests.

Background: The diagnosis of diseases caused by nontuberculous mycobacteria (NTM) is difficult, because NTM are prevalent in the environment such as soil and water, and because they have fastidious properties. In this study we investigated clinical isolates of NTM for their distribution pattern and accurate species identification., Methods: We selected presumptive NTM isolates negative for probe hybridization for M. tuberculosis complex, cultured in a third referral hospital from 21 January 2003 to 20 January 2004. Ninety seven-isolates were identified to the species level by direct sequencing of fragments of 16S rRNA, hsp65 and rpoB genes. A total of 120 isolates were studied for the distribution analysis., Results: Frequently identified NTM species were M. avium (30.8%), M. intracellulare (23.3%) and M. abscessus (18.3%). Others were M. gordonae, M. senegalense, M. fortuitum, M. peregrinum, M. kansasii, M. terrae complex, M. lentiflavum, M. chelonae, and M. szulgai. Three M. tuberculosis complex (2.5%) were also identified among the presumptive NTM isolates. The identification rate by sequencing of 16S rRNA, rpoB, and hsp65 were 65%, 82% and 87%, respectively. The hsp65 or rpoB gene was more efficient than 16S rRNA for the identification of NTM by sequencing., Conclusions: Some NTM are increasingly considered to be the causative organisms in clinical diseases. Thus, direct sequencing could be adapted to routine work of clinical laboratories for accurate identification of NTM to the species level.