Background: Streptococcus agalactiae (GBS) is the causative pathogen of puerperal sepsis in pregnant women and pneumonia, sepsis and meningitis in infants. Infection of GBS is responsible for the increased morbidity in pregnant women and the elderly, and bring challenges to clinical diagnosis and treatment. However, culture-based approaches to detect S.agalactiae is time-consuming with limited sensitivity. Besides, real-time quantitative PCR demands expensive instruments with tedious steps. Thus, we aim to establish a new detection method for more accurate and rapid detection of S.agalactiae. Results: The ddPCR primer targeted the CpsE gene showed better amplified efficiency in the reaction. The limit of detection for GBS DNA with ddPCR was able to reach 5 pg/μL. Moreover, no positive amplified signals could be detected in the reactions which served 11 non-GBS strains DNA as templates. Furthermore, the coefficient of variation of this method was 4.5%, indicating excellent repeatability of ddPCR assay. Conclusions: In our study, ddPCR was performed as a rapid detection of S.agalactiae with high sensitivity and specificity. This technique can promote the accuracy of the diagnosis of GBS infection and provide a scientific basis for clinical treatment.

Background Twin pregnancy poses a high risk, and its incidence has increased in recent years. Establishment of reference intervals of complete blood count (CBC) for women with twin pregnancies during pregnancy may aid in the prognosis of adverse outcomes. Methods The incidence of complications and the intensity associated with adverse outcomes were analyzed in 1153 cases of twin pregnancy. A total of 253 cases in the twin pregnancy reference cohort were screened from all candidates after complications and adverse pregnancy outcomes were excluded. Complete blood count data were collected during the mid- and late-term of pregnancy and analyzed using SPSS to establish the reference intervals for peripheral blood in twin pregnancy. Results Premature rupture of the membrane and pelvic inflammatory disease were highly positively correlated with adverse outcomes, with OR values of 3.31 and 3.81, respectively. Within the interval population with normal outcomes, red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), and platelet (PLT) values were lower in twin-pregnant women during gestation than in healthy nulligravida women, but the levels of white blood cells (WBC), neutrophils (NEU), and the NEU% increased, especially in the mid-term. The reference intervals of late-term pregnancy were validated using 20 twin pregnancies samples, and then utilized to determine the distinctive CBC characteristics in preterm birth (PTB) pregnancy. Absolute WBC and NEU values increased in PTB pregnancy based on our established reference intervals, which suggests that these may might be prognostic indicators of this adverse outcome. Conclusion Establishing the reference interval of blood cell-related indicators of normal twin pregnancy is helpful for the monitoring and prognosis of gestation.