Evaluation of the Manual Method of Liquid-Based Uterine Cervicovaginal Cytology - By The Manual Method Based on SurePathTM Methodology / 대한세포병리학회지

Liquid-Based Uterine Cervicovaginal Cytology is known to be a sensitive and effective screening method for cervical neoplasm. MonoPrepTM, ThinPrepTM, and SurePathTM methods have been recently used as Liquid- Based Uterine Cervicovaginal Cytology techniques, and the SurePathTM method has been used in Sung-Yoon Reference Laboratory since 2003. The goal of Liquid-Based Uterine Cervicovaginal Cytology is to separate cervical epithelial cells from non-target cells, red blood cells and neutrophils. This report describes a study which evaluated cellularity, stainability, and cellular changes of epithelial cells in samples processed using a manual technique as compared to samples processed using SurePathTM automated method. The samples processed by means of a manual technique contained a cellularity of epithelial cells similar to that of the samples processed using the SurePathTM automated method. In addition, we compared variable density gradient reagents, including dextran, dextrose, and sucrose, to SurePathTM gradient media in order to evaluate cell fractionation and cellularity of epithelial cells. 10% dextran of gradient media shows good fractionation. The samples processed with 10% dextran demonstrated sufficient cellularity of epithelial cells and shows the fewest cellular changes. In conclusion, using a manual technique on these samples is easier to read than those results obtained using the SurePathTM automated method.

Transfusion-Induced Malaria in a Child after Open Heart Surgery in Korea

We had an opportunity to evaluate a child who developed fever approximately two to three weeks after the open heart surgery for tetralogy of Fallot. His peripheral blood smear showed rings and various stages of Plasmodium vivax. The patient had received packed red blood cells during the surgery and postoperative care, one unit of which was later proved sero-positive for malaria. The possibility of malaria should be included in the differential diagnosis of the patients with unexplained fever after multiple blood product transfusions for the open heart surgery.

Detection of Penicillin-resistant Streptococcus pneumoniae by Polymerase Chain Reaction / 대한임상병리학회지

BACKGROUND: Resistance to penicillin of Streptococcus pneumoniae in clinical isolates has occurred by the development of altered penicillin-binding proteins (PBPs) that have greatly decreased affinity for antibiotics and has been encountered with increasing frequency in Korea. In this study, the identification of altered PBPs of S. pneumoniae in clinical isolates by using polymerase chain reaction (PCR) and relationship of PCR with the conventional antibiotic susceptibility test of penicillin were evaluated. METHODS: Thirty isolates of S. pneumoniae from clinical specimens were used. Four sets of PCR primers of penicillin-sensitive and -resistant S. pneumoniae were designed to amplify (i) PBP 2BS: a 360 base pair fragment of the PBP 2B gene, (ii) PBP 2BCA: a 350 base pair fragment of the class A mutations present in PBP 2B gene, (iii) PBP 2BCB: a 295 base pair fragment of the class B mutations present in PBP 2B gene, and (iv) PBP 1AR: a 434 base pair fragment of the PBP 1A gene. In addition, a set of primers that amplify 273 base pair of the autolysin gene (ALY) was applied in combination with the above to identify S. pneumoniae. PCR results were compared with antibiotic susceptibility test (disk diffusion test and penicillin MIC). RESULT: Among 30 clinical isolates tested, 80% of isolates were penicillin resistant. The results of antibiotic susceptibility test were same as those of PCR methods. Among 24 penicillin resistant isolates detected by PCR methods, 5 isolates revealed PBP 2BCB gene, but 19 isolates revealed both of PBP 2BCB and 1AR genes. Five isolates with PBP 2BCB gene showed lower range of penicillin MIC (0.19 ~ 1.0 g/mL) than 19 isolates with PBP 2BCB and 1AR genes (0.75 ~ 4.0 g/mL). CONCLUSION: Detection of altered PBP genes of S. pneumoniae by PCR may be performed for the study of penicillin resistance. This study indicates that more altered PBPs in 1AR genes are related with higher MICs.

Quantitative Measurement of Hepatitis B Virus DNA by Competitive Nested Polymerase Chain Reaction / 대한임상병리학회지

BACKGROUND: We performed competitive nested polymerase chain reaction (PCR) to evaluate the clinical utility of quantitative measurement of HBV DNA by PCR and it's correlation with other serologic hepatits B markers. Because hepatitis markers such as HBsAg, HBeAg, anti-HBe can not accurately reflect the replication of hepatitis B virus (HBV). METHODS: The internal standard was generated from the HBV core gene by point mutation, which would result in restriction site for the restriction enzyme Eco RI and performed competitive nested PCR followed by densitometric scanning of the amplified products of agarose gel. RESULTS: The sensitivity of nested PCR was 5 molecules in direct observation of agarose gel, but because of the background effect as taking polaroid photo graph it was 50 molecules by using densitometer. When DNA pellets for original 250 microL serum were diluted with 40 microL distilled water the low detection limit was 5.0 x10(3) molecules/microL, however it could be lowered when less diluted. Lower detection limit of densitometer was 6.25 pg by twofold serial dilution of 100 pg of purified HBV DNA PCR products, and regression showed y=0.93x-0.33 (y : density, x : concentration, 6.25 pg considered as 6.25 density). The reproducibility of the densitometer from high concentration was 4.3 +/-0.6 x10(6) molecules/microL(mean +/-SD, CV 14%), and low concentration was 3.7 +/-0.7 x10(4) molecules/microL(mean +/-SD, CV : 20%) Higher concentration of HBV DNA in HBeAg positive cases comparing with HBeAg negative cases was statistically significant (p<0.01). There was no correlation between HBV DNA concentration and serum value of alanine aminotransferase. CONCLUSION: Quantification of HBV DNA should be very useful in clinical follow-up of Post-therapy Patients and in anticipating Prognosis and infectivity of the disease, especially in cases of atypical hepatitis B and hepatitis B without seroconversion of routine hepatitis B markers. The shortcoming of the method seemed to be a rough estimate of HBV concentration as measuring the ratio of specimen/internal standard of two consecutive concentration among 10 folds serially diluted internal standard.