ABSTRACT
Objective To evaluate the clinical value of neonatal peripheral blood smear spherical erythrocyte count in the diagnosis of ABO-HDN.Methods 165 cases clinically diagnosed with ABO-HDN in Zhongshan Boai Hospital from 2009 to 2015 were listed as the experimental group by retrospective analysis,68 cases of non-ABO-HDN were listed as control group.Besides,relevant clinical data and experimental examination were investigated,and the results of their hemolysis test were analysed.Results Peripheral blood smear spherical erythrocyte count were positive in 110 cases of 165 patients with ABO-HDN,the positive rate of spherical erythrocytes was 66.7 ％ (x2 =58.069,P＜ 0.05).The spherical erythrocyte positive rates were 68.8 ％,60.5 ％ and 66.7 ％ in patients aged ≤2d,3 ～4d,≥5d respectively.The diagnostic sensitivity of spherical erythrocytes to ABO-HDN was 66.7 ％,the specificity was 88.2 ％,the positive predictive value was 93.2 ％,and negative predictive value was 52.2 ％.When spherical erythrocyte count positive point was set as ≥5 ％ spherical erythrocytes,the diagnostic sensitivity of spherical erythrocytes to ABO-HDN was 66.7％ and the specificity was 88.2％.If the positive point was set as ≥10％ spherical erythrocytes,the sensitivity of ABO-HDN decreases to 9.3％,and the specificity reaches 98.5 ％.In ABO-HDN group,the levels of nucleated red blood cell,RDW and Ret were higher,along with the lower level of hemoglobin compared with non-ABO-HDN group (all P＜0.05).Conclusion The peripheral blood smear spherical erythrocyte count had a high sensitivity and specificity for the diagnosis of ABOHDN.Combined with jaundice,anemia and RDW,peripheral blood smear spherical erythrocyte count can provide guidance for the early diagnosis,prevention and treatment of ABO-HDN.
ABSTRACT
<p><b>OBJECTIVE</b>To establish a quick and reliable method to identify Streptococcus oligofermentans, a new species of oral streptococci.</p><p><b>METHODS</b>With two-step PCR, a pair of the 16S rDNA-specific primers of Streptococcus oligofermentans and a pair of primers of lactate oxidase gene (lox) were used to amplify the gene fragments from the genomic DNAs of 11 strains consisting of 9 species of the pure culture of oral streptococci. Pooled plaque samples from 9 caries-free volunteers were cultured on a selective medium of MSA with erythromycin and tentative strains of Streptococcus oligofermentans were isolated. The isolates were further identified by the two-step PCR and finally confirmed by 16S rDNA sequence analysis.</p><p><b>RESULTS</b>With the two-step PCR, the two gene fragments were only amplified from the three identified strains of Streptococcus oligofermentans, but not the rest of 8 strains of oral streptococci. Isolates from the dental plaque of caries-free volunteers were identified as Streptococcus oligofermentans by PCR and then further confirmed by 16S rDNA sequence homology analysis.</p><p><b>CONCLUSIONS</b>Streptococcus oligofermentans could be identified by the two-step PCR approach with the specific 16S rDNA primers and lactate oxidase gene primers.</p>